packed tower internals guide -...

56
Packed Tower Internals Guide

Upload: trandiep

Post on 20-Mar-2019

307 views

Category:

Documents


13 download

TRANSCRIPT

Page 1: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

Packed Tower Internals Guide

Page 2: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

TABLE OF CONTENTS

Introduction Packed Tower Internals Guide

A. Liquid Distributors Liquid Distributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-1Intalox Distributors for Demanding Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-5Model 106/107 Intalox Pan Distributor/Redistributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-6Model 116/117 lntalox Deck Distributor/Redistributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-7Model 126/127 Intalox Trough Distributor/Redistributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-8Model 136/137 Intalox Pan or Trough Distributor/Redistributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-9Model 166 Intalox Trough Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-10Model 186 Intalox Trough Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-11Traditional Distributors for Absorption, Stripping, or Heat Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-12Model 845 Pan Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-13Model 798 Pan Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-14Model 816/817/916/917 Deck Distributor/Redistributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-15Model 806 Trough Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-16Model 1016/1017 Trough Distributor/Redistributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-17Model 844 Pipe-Arm Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-18Model 1044 Spray-Type Liquid Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-19

B. Feed Devices Feed Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-1Model 119/129 Liquid Only Feed Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-3Model 719/729 Liquid Only Feed Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-4Model 755 Flashing Feed Gallery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-5Model 855 Flashing Feed Chamber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-6Model 955 Flashing Feed Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-7Model 196 Vapor Diffuser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-8Model 198 Vapor Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-9Model 896 Vapor Distributor Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-10

C. Bed Limiters Bed Limiters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-1Model 823 Bed Limiter for Random Packing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-2Model 103 Non-Interfering Bed Limiter for Random Packing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-3Model 133 Bed Limiter for Structured Packing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-3

D. Support Plates Support Plates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-1Model 818 Gas Injection Support Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-2Model 804 Gas Injection Support Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-3Model 809 Light Duty Support Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-4Model 819/1019 Gas Injection Support Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-5Model 134 Support Grid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-6

E. Collector Plates Liquid Collectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-1Model 633 Chevron-Type Liquid Collector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-2Model 733 Trough Liquid Collector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-3Model 833 Deck Liquid Collector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-4

F. Liquid/Liquid Extraction Liquid/Liquid Extraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F-1Model 834 Disperser/Support Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F-2Model 835 Disperser/Support Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F-3Model 644 Dispersed-Phase Feed Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F-4Model 744 Continuous-Phase Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F-4

G. Other Topics Typical Tower Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-1General Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-2Materials of Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-3Special Tower Internals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-4Other Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-5

Page 3: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

PACKED TOWER INTERNALS GUIDE

Saint-Gobain NorPro’s (formerly NortonChemical Process Products Corporation)dedication to providing state-of-the-artmass transfer equipment has resulted inmajor developments with packed towerinternals. Liquid distribution has long beenregarded as the key to precise packedtower performance. Saint-Gobain NorPromade the commitment to determine whatfactors are really important toward “perfect” liquid distribution. We installed a10 ft [3 m] diameter by 40 ft [12 m] tallhydraulic simulation column at ourresearch facility. With this column, westudy the effects of various liquid andvapor flow rates. The result: Saint-GobainNorPro confidently designs internals forany size tower from the beginning withoutthe need to test each internal before shipping, although such testing is available on request.

We recognize that not all packed towersrequire state-of-the-art liquid distributionuniformity. For those towers, we still offerour traditional style internals. The traditional style internals have been usedfor many years in services that requirematerials ranging from carbon steel to zirconium, thermoplastics, fiberglass,graphite and ceramics.

This guide is intended to assist in the selection of appropriate towerinternals for use in packed towers. Thewide range of applications does notallow us to cover all the choices andvariation Saint-Gobain NorPro offers.As always, we offer our expertise incustom design of proper equipmentfor your exact requirements. Call onour application experience to helpsolve your mass transfer needs.

Page 4: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

LIQUID DISTRIBUTORS

Introduction

Liquid distributors are used in packed towers above each bed of packing.

The liquid distributor is located above the bed, usually 6 to 8 in. [150 – 200 mm] above the packing. This provides sufficient space for the gas to disengage from the bed before it passes through the distributor.

An ideal distributor possesses the following attributes, each with a specificeffect on the overall performance of apacked tower:

■ Uniform liquid distribution

■ Resistance to plugging or fouling

■ Proper turndown capability

■ Low gas pressure drop

■ Minimal distributor height to allowmore packed bed heights

■ Cross-mixing capability

The introduction of high performancetower packings in the early 1980s accentuated design deficiencies of distributors available at the time. Inresponse, Saint-Gobain NorPro introduceddistributors with attributes designed to correct these deficiencies. These attributesare well-understood by us and have beenincorporated in NorPro™ Intalox®

distributors.

We offer two major categories of liquid distributors to meet the requirementsof specific applications. In determiningwhich category to choose, it is necessaryto know how sensitive the tower perform-ance is to distribution uniformity. Will aslight variation of distribution quality significantly affect the tower performance?

As a rule:

■ NorPro Intalox distributors…

Used primarily for distillation services, typically where a high-efficiency packing (IMTP® randompacking, Intalox® wire gauze orIntalox® structured packing) is used.Deep beds of any type of packingrequire Intalox® distributors to maximize performance.

■ NorPro traditional distributors…

Used for most absorption, stripping,and heat transfer services. Serviceswhere a traditional packing (Pallrings, Hy-Pak® packing, Intalox®

saddles, Raschig rings, etc…) isused will usually use these less costly distributors.

Redistributors share the same mechanicaldesign characteristics as distributors, butthey also include gas riser covers and pos-sibly wall wipers to collect all liquid rainingdown from the packing above. The ques-tion of when to redistribute liquid is noteasy to answer.

There are four reasons to have more thanone bed of packing in a tower: feed introduction, liquid cross-mixing, distribu-tion correction and product side-draws.Introduction of a feed (liquid or vapor) intoa tower with packing above and belownearly always requires a split in the bedsfor a redistributor.

An important factor to keep in mind withthe introduction of an external feed is thatof mixing (homogenization of compositionor temperature). Mixing of liquid should beconsidered when:

■ A tower has deep beds or;

■ A feed is sub-cooled more than 30° F [17° C] or;

■ A feed composition differs from theinternal flow

Cross-mixing is an optional feature onmost of our trough-type redistributors. Byeliminating the need for liquid collection ina separate collector plate, the cross-mixingoption saves equipment and frees towerspace for more packing.

Based on our operating experience, a conservative rule-of-thumb to use whendetermining maximum depth is: A packedbed should be no higher than 15 times the tower diameter and contain less than20 theoretical stages. With proper attention to initial distribution uniformity,bed depths may be greater. However, we do not recommend exceeding this limitwithout consulting a Saint-Gobain NorProtechnical representative.

A-1

Page 5: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

LIQUID DISTRIBUTORS

Distribution Quality

Perfect liquid distribution could be definedas providing equal liquid rate per unit areaof the packed bed surface. Many practicalfactors restrict the achievement of this.

Liquid can be applied by sprays, weirs, ororifices. Sprays can almost totally wet thesurface of a packed bed, but the point-to-point flow variation is high. Weir distribu-tors provide discrete streams but flow variation is difficult to control. Orifice distributors direct liquid to packing in discrete streams. “Perfection” requires aninfinite number of streams each of equalflow. However, orifice size, fouling considerations, and mechanical construc-tion details prevent high unit area pointcount from being achieved.

Intalox distributors aim toward “perfection”:

(a) Orifices are laid out on a triangularpattern, (preferred) or on a squarepattern, uninterrupted by gas chimneys or mechanical supports,properly spaced to the vessel wall.

(b) Liquid flow from each orifice is nearly equal to all others.

NorPro “traditional” distributor patterns arenot as good as Intalox patterns. The number of distribution points per unit areais generally below that of an Intalox distributor. Flow variations among the distribution points are greater than allowedfor Intalox distributors. However, the traditional distributors have been used suc-cessfully for many years in a wide range ofprocesses.

Saint-Gobain NorPro developed a distributor rating system for quantifyingdistribution quality, or performance. Werate distribution uniformity as a percent-age, where 100% indicates ideal uniformdistribution and low percentage ratingsindicate that parts of the tower receive a liquid flow significantly different fromother parts.

For more information regarding our rating system, request a copy of the publication, “Liquid and Gas Distribution in Commercial Packed Towers.”

The significance of our distribution qualityrating system is that the distributor ratingcorrelates with tower performance.

A tower containing deep beds of high-efficiency packing is sensitive to liquid distribution quality, whereas a tower containing shallow beds of a traditionalpacking is less sensitive to distributionquality.

Stages Per Bed WithSystem Base HETP

20

16

12

8

4

10 20 30 40 50 60 70 80 100900

The effect of liquid distribution quality on towerperformance is shown by these actual results:

Distribution Quality (%)

Act

ual S

tag

es P

er B

ed o

f P

acki

ng

2

4

6

8

10

12

14

16

18

20

0

Intalox distributors are always recommended in:

■ High purity product distillation services

■ Distillation services operating closeto minimum reflux

■ Heat transfer services with closetemperature approach

■ Services with high stage count per bed

TOWER PERFORMANCE CORRELATES WITH DISTRIBUTION QUALITY

A-2

Page 6: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

IMTP PackingNo. 25/40/50/60/70

Intalox Structured Packing1.5T/2T/3T/4T/5T

5.6 – 7.5 pts/ft2

60 – 80 pts/m2

IMTP PackingNo. 15

Intalox Structured Packing1T

5.6 – 9.3 pts/ft2

60 – 100 pts/m2

Intalox Structured PackingHS-10 / HS-20

7.9 – 10.2 pts/ ft2

85 – 110 pts/m2

Intalox Wire Gauze Packing

9.3 – 11.1 pts/ ft2

100 – 120 pts/m2

LIQUID DISTRIBUTORS

Point Count

The number of distribution points per unitarea has an influence on the efficiency ofthe uppermost part of a packed bed.When using larger packings, with relativelylow efficiency, the effect of the number ofdistribution points is insignificant. However,the effect can be considerable when usingsmaller, high-efficiency packings.

Saint-Gobain NorPro has establishedguidelines for Intalox distributors with high-performance packings as shown below.

In practice, a lower number of distributionpoints per unit area may be the only way ofachieving acceptable orifice diameters.

The number of distribution points per unitarea can be designed as required; however, mechanical considerations usually limit the number to about 18.6 pts/ft2 [200 pts/m2].

Cross Flow

As the liquid rate on a distributor isincreased, its cross flow capability and itsprimary (pre) distribution system becomemore important.

The cross flow capability of a distributorreflects its ability to balance liquid from onepart of the distributor to another. It isimportant to balance liquid on all gravity-fed distributors. However, at high specificliquid rates the liquid cross flow capacitymust be large to correct for system imperfection.

The primary distribution of liquid into a distributor has been shown to have a significant effect on overall distributor performance. It is important that the feedsystem meters flow to one or more appropriate points without excessive turbulence or horizontal velocity. This isachieved by use of feed pipes and/or parting boxes. The design of the primarydistribution system becomes increasinglycomplex as the specific liquid rate and thecolumn diameter increase.

Fouling

If a distributor is to perform correctly it isimportant that metering devices (orifices orweirs) do not become fouled, since foulingsignificantly reduces packing performance.

There are several mechanisms of distributor fouling: polymerization, sedimentation, coking, scale, debris, etc.All precautions to eliminate fouling outsidethe column should be adopted since external strainers are far easier to cleanthan distributors. Regardless, the distributor should be considered for itsdegree of fouling resistance.

V-shaped weirs are less prone to blockagethan orifices; orifices in a side wall are generally less prone to blockage than orifices in the bottom of a distributor; orifices protected by an orifice strainer areless prone to blockage by a particulatematerial than unprotected orifices. Orificestrainers are not recommended in systemsthat tend to coat surfaces.

NorPro Intalox distributors with bottom orifices are not normally recommended fororifice sizes of 0.25 in. [6 mm] or less dueto their fouling propensity. Intalox distribu-tors designed with weirs may have flowvariation outside the high-performancerange.

The list below ranks the fouling resistanceof the various metering arrangements atany given flow rate (most resistant - top, to least - bottom):

■ “V” weir/spray

■ Slotted weir

■ Side wall orifice with orifice strainer

■ Side wall orifice

■ Bottom orifice with orifice strainer

■ Bottom orifice

Orifice strainers can protect a distributorfrom fouling with particulate matter such aswall/pipe scale. Each orifice’s flow passesthrough a higher-surface-area strainerbefore approaching the metering orifice.However, orifice strainers are not effectivewhen fouling material pastes, coats orsticks to metal. Other effective methods ofprotecting distributors from fouling includeusing sidewall orifices (positioned up from the bottom of the distributor) or using weirs.

INTALOX DISTRIBUTOR POINT COUNT

A-3

Page 7: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

LIQUID DISTRIBUTORS

Operating Range

A distributor will generally give its best performance at liquid rates close to 100%of design flow, with the performance deteriorating as the liquid rate is reduced.At 100% design flow, NorPro Intalox distributors usually give a flow variation atany point of the distributor of better than±5% and at minimum rates better than±8%. This will generally give an operatingrange of 2:1 for a single-level orifice distributor. If the minimum rate specifica-tion is such that a wider flow variation canbe accepted, then a wider operating rangeis possible.

NorPro “traditional” distributors operatewith much higher flow variations over atypically broader range of operations thanIntalox distributors.

Figure 2 shows the flow variation for theflow through a single-level orifice. The useof a multi-level orifice enables the flow variation for the Intalox distributor to bemaintained over a very wide operatingrange.

Special designs of Intalox distributors canbe made for processes requiring lower flowvariations. Designs of better than ±3% at100% design rate and better than ±5% ata 2:1 turndown are feasible. These designswill generally include special primary distribution systems (feed pipes, partingboxes, etc.)

Orifice Size

In gravity-fed orifice distributors, the orificesize is dependent mainly upon the holecount, the specific liquid rate and the liquid head. For Intalox distributors with an operating range of 60 to 120% of thedesign flow, the approximate orifice size isindicated in Figure 3.

% Liquid Load

Traditional Distributors

Intalox Distributors

Design Range

IncreasedFlow

Variation

IntaloxDistributors

Criteria

Turndown 100%Design Turnup

Flo

w V

aria

tion

FloodedDistributors

11.2 PTS/ft2 (120 PTS/M

2 )

No

rmal

Flo

w (g

pm

/ft2

)

Orifice Diameter (inches)

4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 2410080

6050

40

30

20

10

8

654

3

2

10.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

9.3 PTS/ft2 (100 PTS/M

2 )

7.4 PTS/ft2 (80 PTS/M

2 )

5.6 PTS/ft2 (60 PTS/M

2 )

Orifice Diameter (mm)

250200

150

100

50

25

20

15

10

5

(m

3 /h•

m2 )

EFFECT OF OPERATING RANGE

APPROXIMATE ORIFICE SIZING

Figure 2

Figure 3

A-4

Page 8: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

INTALOX DISTRIBUTORS

A specific Intalox distributor is chosen byconsidering tower diameter, flow rate, turndown ratio, available height and foulingresistance. Each distributor style featuresdesign options which adapt it to a particular application.

The table to the right provides a preliminarychoice of a distributor suitable for yourservice conditions. A detailed descriptionthat will enable a final selection to be madeis given on the following pages. Consultyour Saint-Gobain NorPro representativefor assistance or for final confirmation.

ColumnDiameterin. [mm]

10 - 36[250 - 900]

> 36 [900]

*Flow variation will be outside normal Intalox distributor parameters.

Specific Liquid Rategpm/ft2

[m3/h•m2]

SystemFouling

TendencyTurndown

RatioSuggested

Model

< 0.3 gpm/ft2[0.75 m3/h•m2]

0.3 - 2 gpm/ft2[0.75 - 5 m3/h•m2]

2 - 12 gpm/ft2[5 - 30 m3/h•m2]

> 12 gpm/ft2[30 m3/h•m2]

> 0.8 gpm/ft2[2 m3/h•m2]

Low

Low/Medium

LowMedium

High

< 10:1

2:12:1 - 10:1

< 10:1

2:1< 10:1

< 10:1

< 10:1< 10:1

136 Special

136

106136136

106136 Special

136 with weirs*

Low

Medium

0.3 - 2 gpm/ft2[0.75 - 5 m3/h•m2]

2 - 12 gpm/ft2[5 - 30 m3/h•m2]

> 12 gpm/ft2[30 m3/h•m2]

LowMedium

LowMedium/High

Low

MediumHigh

2:12:1 - 10:1

< 10:1< 10:1

2:1< 10:1

186 Special166

136 or 186166

126136 or 186136 or 186

166

116136 Special

<0.3 gpm/ft2[0.75 m3/h•m2]

< 10:1

S y s t e m C h a r a c t e r i s t i c s

< 10:1< 10:1

LowMedium

SELECTING AN INTALOX DISTRIBUTOR

A-5

Page 9: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 106/107 INTALOX PAN DISTRIBUTOR/REDISTRIBUTOR

■ Diameters 10 - 36 in. [250 – 900 mm]

■ Orifices in base

■ Liquid rates above 2 gpm/ft2

[5 m3/h•m2]

The pan-type construction of the Model106 Intalox distributor and Model 107Intalox redistributor is designed for towersless than 36 in. [900 mm] ID with minimumliquid rates in excess of 2 gpm/ft2

[5 m3/h•m2]. Lower rates can be accom-modated but the Models 136/137 shouldbe considered first. This distributor can be leveled. In towers less than 24 in. [600 mm] ID, one-piece construction, for installation through a body flange, isstandard. A special multi-piece construction is available upon request.

Orifices in the pan bottom are arranged toprovide optimum distribution quality, withgas risers set between the orifices. Smalldiameter pans may not have gas risers asgas passage is provided in the gapbetween the pan and the vessel wall.When used for higher flow rates, this distributor will have large orifices that willnot tend to foul. For lower flow rates, orifice strainer caps or the Model 136/137should be considered if the system is fouling. The standard turndown range is 2:1.

For single-phase liquid feeds to the distributor, a feed pipe to control feedvelocity to the deck is required. Two-phaseliquid and vapor feeds require a flashingfeed device to adequately separate phases and assure proper liquid feedvelocity. Refer to “Liquid/Vapor FeedDevices,” Section B, for selection assistance.

The Models 106/107 are available in anyweldable sheet metal. Carbon steel is notrecommended except for very high liquidrates where orifice corrosion will not significantly affect distribution quality. FRP and thermoplastic construction areavailable, although such constructionreduces distribution quality.

Standard connection to the tower wall isby bolting to clips. Optionally, the distribu-tor can be suspended from a ring trappedbetween body flanges. Setting the distributor on an annular ring is not recommended.

All joints in multi-piece pans are gasketed.See Section G for material requirements.

The standard design for a Model 107redistributor includes gas riser covers anda weld-on wall wiper, as shown below.

■ Orifice strainers

■ Expandable and gasketed wall wiper (Model 107)

■ Suspended mounting

■ Non-standard point count(See Page A-3)

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Support cliparrangement

Height varies with turndown.

OF FEEDINLETNOZZLEWHEN USED

CL

40mm

15mm DIA. HOLE

120.0° REF.

A

B

18"[450]

12"[300]

Model 106

Model 107

60.0° REF.

A-6

Page 10: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 116/117 INTALOX DECK DISTRIBUTOR/REDISTRIBUTOR

■ Diameters greater than 36 in. [900 mm]

■ Liquid rates above 12 gpm/ft2

[30 m3/h•m2]

■ Orifices in deck

The Model 116 Intalox distributor andModel 117 Intalox redistributor are for tow-ers with minimum liquid rates in excess of12 gpm/ft2 [30 m3/h•m2]. Lower rates canbe accommodated by Models 126/127 or136/137.

The deck-type construction allows goodliquid cross-flow between gas risers whichare set between orifices specifically spacedfor distribution quality. Because this platenormally handles higher liquid flow rates,the orifices are usually large and do nottend to foul. The standard turndown rangeis 2:1.

For single-phase liquid feeds to the distributor, use a feed pipe to control feedvelocity. Two-phase liquid-vapor feedsrequire a flashing feed device to adequate-ly separate phases and assure proper liquid feed velocity. Refer to “Liquid/VaporFeed Devices,” Section B, for selectionassistance.

The Models 116/117 are available in anyweldable sheet metal. Carbon steel is notrecommended except for very high liquidrates where orifice corrosion will not significantly affect distribution quality. FRP construction is available, although it reduces distribution quality.

The Models 116/117 distributor areclamped onto an annular ring that is seal-welded to the tower wall, with clampsprovided. Hence, distributor levelness isdetermined by the ring levelness; we consider levelness tolerances in the116/117 design. All joints are gasketed.See Section G for ledge and materialrequirements.

The standard design for a Model 117redistributor includes gas riser covers tocollect and redistribute liquid raining fromabove.

■ Orifice strainers

■ Anti-migration bars in gas risers

■ Non-standard point count(See Page A-3)

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 116

Height varies with turndown.

Standard design passes through 18 in.[450 mm] nominal manway.

Model 117

A

B

14"[350]

18"[450]

A-7

Page 11: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 126/127 INTALOX TROUGH DISTRIBUTOR/REDISTRIBUTOR

■ Diameters greater than 36 in. [900 mm]

■ Orifices in base

■ Liquid rates between 2 and 16 gpm/ft2 [5 – 40 m3/h•m2]

The Model 126 Intalox distributor andModel 127 redistributor are designed fortowers greater than 36 in. [900 mm] IDwith minimum liquid rates in excess of 2 gpm/ft2 [5 m3/h•m2]. Lower rates can beaccommodated but the Models 136/137should be considered first. For systemswith liquid rates in excess of 12 gpm/ft2

[30 m3/h•m2] the Model 116/117 should be considered first.

The trough-type construction allows easyliquid sealing and distributor leveling, which is essential in large diameter towers.Because this distributor normally handlesintermediate liquid flow rates, the orificesare usually large enough to allow moderatefouling resistance. If the system is foulingand/or the orifices are small, orifice strainercaps or the Model 136/137 should be considered. The standard turndown range is 2:1.

For single-phase liquid feeds to the distributor, use a feed pipe to control feedvelocity. Two-phase liquid-vapor feedsrequire a flashing feed device to adequate-ly separate phases and assure proper liquid feed velocity. Refer to “Liquid/VaporFeed Devices,” Section B, for selectionassistance.

The Models 126/127 are available in anyweldable sheet metal. Carbon steel is notrecommended except for very high liquidrates where orifice corrosion will not significantly affect distribution quality. TheModel 126/127 rests on an annular ring oris suspended from a ring or beams. Alljoints are gasketed. See Section G forledge and material requirements.

FRP or thermoplastic construction is available, although use of these materialsmay reduce distributor performance.Thermoplastic construction may be limitedto spans of less than 6 ft [2 m], depending on operating temperatures.

The standard design for a Model 127redistributor includes a weld-on wall wiperand gas riser covers to collect and redistribute liquid raining from above. FRPand thermoplastic construction require aproperly designed wall wiper field connected/bonded to the vessel wall.

■ Cross-mixing capability

■ Orifice strainers

■ Leveling screws

■ Non-standard point count (See Page A-3)

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 126

Height varies with turndown.

Standard design passes through 18 in.[450 mm] nominal manway.

Model 127

A

B

20"[500]14"

[350]

A-8

Page 12: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 136/137 INTALOX PAN OR TROUGH DISTRIBUTOR/REDISTRIBUTOR

■ Diameters greater than 10 in. [250 mm]

■ Side-wall orifices

■ High turndown ratio

■ Standard liquid rates between 0.3and 12 gpm/ft2 [0.75 – 30 m3/h•m2]

The Model 136 Intalox distributor andModel 137 Intalox redistributor are for towers greater than 10 in. [250 mm] IDwith liquid rates between 0.3 and 12 gpm/ft2 [0.75 - 30 m3/h•m2] where fouling protection and/or high turndown isrequired. Special designs can handle liquidrates from 0.08 to 0.3 gpm/ft2

[0.2 - 0.75 m3/h•m2]; for these cases, theModel 120 strainer basket should be considered to protect the small flow orifices. Special designs can also handleliquid rates above 12 gpm/ft2 [30 m3/h•m2].

The Models 136/137 are usually constructed as pans for diameters below30 inches [750 mm] and as troughs fordiameters above 30 inches [750 mm]. Thestandard turndown for a single sidewall orifice is 2:1; however, the turndown range can be extended by using two orthree orifices at different levels of the same discharge point. Turndown ratios up to 10:1 are achievable. The liquid fromeach discharge point is conducted into the lower vapor velocity region below thedistributor troughs. This results in lowentrainment levels.

The resistance to fouling of this distributoris higher than that of deck-type distributorsbecause it features a debris collection zonebelow the sidewall orifices. Weirs can beused as an alternative to orifices in highfouling systems. However, flow variationwill be outside normal Intalox parameters.

For single-phase liquid feeds to the distributor, a feed pipe or a feed pipe/parting box combination is required tocontrol feed velocity to the troughs. Two-phase liquid-vapor feeds require useof a flashing feed device to adequatelyseparate phases and assure proper liquidfeed velocity. Refer to “Liquid/Vapor FeedDevices,” Section B, for selection assistance.

The Models 136/137 are available in anyweldable sheet metal. Carbon steel is notrecommended except for very high liquidrates where orifice corrosion will not significantly affect distribution quality.Thermoplastic construction is available,although such construction reduces distribution quality.

The Model 136/137 rests on an annularring or is suspended from beams or clips.All joints are gasketed. See Section G forledge and material requirements.

All distributors and redistributors includeoverflow orifices which help prevent distributor flooding during liquid surges.

The standard design for a Model 137redistributor includes a weld-on wall wiperon the vessel wall and gas riser covers tocollect and redistribute liquid raining downfrom above.

■ Cross-mixing capability (in towersgreater than 55 in. [1400 mm] ID)

■ Orifice strainers

■ Leveling screws

■ Expandable and gasketed wall wiper(small Model 137)

■ Non-standard point count(See Page A-3)

CONSTRUCTION DETAILS

DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 136

Height varies with turndown.

Standard design passes through 18 in.[450 mm] nominal manway.

Model 137

14"[350]

20"[500]

A

B

A-9

Page 13: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 166 INTALOX TROUGH DISTRIBUTOR

■ Diameters greater than 30 in. [750 mm]

■ Sidewall orifices with flow pointmultipliers

■ Liquid rates between 0.2 and 4.0gpm/ft2 [0.5 – 10 m3/h•m2]

The Model 166 Intalox distributor is fortowers greater than 30 in. [750 mm] IDwith liquid rates between 0.2 and 4.0 gpm/ft2 [0.5 - 10 m3/h•m2]. Thetroughs on the Model 166 liquid distributormeter liquid accurately at 0.8 - 2 points per ft2 [9 - 20 points per m2] through sidewall orifices. Because of the low pointdensity, the sidewall orifices are as large as possible for fouling resistance. The conductor tubes from each metering orificedischarge the liquid to spreading plates orchannels that greatly multiply the 0.8 - 2points/ft2 [9 - 20 points/m2] into many moredrip points before the liquid is releasedonto the packing.

The standard turndown ratio of the Model166 liquid distributor with single-level orifices is 2:1; however, the turndownrange can be extended by using two orthree orifices at different levels for eachconductor tube.

For single-phase liquid feeds to the distributor, a feed pipe or a feed pipe/parting box combination is required tocontrol feed velocity to the troughs. Two-phase liquid-vapor feeds require useof a flashing feed device to adequatelyseparate phases and assure proper liquid feed velocity. Refer to “Liquid/VaporFeed Devices,” Section B, for selectionassistance.

The Model 166 liquid distributor is available in any weldable sheet metal.Carbon steel is not recommendedbecause of the potential for metering orifice corrosion. The Model 166 is suspended from beams or clips and isalways leveled during installation. Orificestrainers can be used over the primary distribution orifices.

■ Orifice strainers

DESIGN OPTIONSCONSTRUCTION DETAILS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Standard design passes through 18 in.[450 mm] nominal manway.

Model 166

A

B

Hd

A-10

Page 14: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 186 INTALOX TROUGH DISTRIBUTOR

■ Diameters greater than 36 in. [900 mm]

■ Sidewall orifice

■ Standard liquid rates between 0.3and 8 gpm/ft2 [0.75 – 20 m3/h•m2]

The Model 186 liquid distributor is for towers greater than 36 in. [900 mm] IDwith liquid rates between 0.3 and 8 gpm/ft2

[0.75 – 20 m3/h•m2] where fouling protec-tion is required. Special designs can han-dle liquid rates from 0.08 to 0.3 gpm/ft2

[0.2 – 0.75 m3/h•m2]; for these cases, the Model 120 strainer basket should beconsidered to protect the small orifices.The standard turndown range of the Model186 is 2:1.

The Model 186 liquid distributor is similarto the Model 136 liquid distributor, withtrough construction sidewall orifices, conductor tubes, and overflow orifices.Compared to the Model 136, however, theModel 186 distributor uses a parting boxover the distribution troughs instead of acenter trough at the same level as the lat-eral distribution troughs. The Model 186distributor therefore requires more columnheight, but it is easier to seal and requiresno gasket. Without the crossflow of a cen-ter trough, the parting box design is crucialto the Model 186 distributor performance.

For single–phase liquid feeds to the distributor, a feed pipe is required to control feed velocity to the troughs. Two-phase liquid-vapor feeds require the use of a flashing feed device to adequatelyseparate phases and assure proper liquid feed velocity. Refer to Section B forselection assistance.

The Model 186 is available in any weldable sheet metal. Carbon steel is not recommended because of the effect of minor corrosion on orifice flow characteristics.

The Model 186 rests on an annular ring or is suspended from beams or clips. See Section G for ledge and materialrequirements.

All distributors include overflow orificeswhich help prevent distributor flooding during liquid surges.

■ Orifice strainers

■ Leveling screws

■ Non-standard point count (See Page A-3)

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Standard design passes through 18 in.[450 mm] nominal manway.

A

B

Hd

Model 186

A-11

Page 15: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

TRADITIONAL DISTRIBUTORS FOR ABSORPTION, STRIPPING, OR HEAT TRANSFER

NorPro traditional distributors are used inapplications that are less demanding onpacking performance, such as generalheat transfer applications and absorptionand stripping services with less than fivetransfer units per bed.

The traditional distributors generally havelower orifice count, less balanced liquidheads (lower liquid head with limited cross-flow capability) and less uniform distribution coverage than Intalox high-performance distributors.

Tower size is the first consideration inselecting a traditional distributor. Typically,towers less than 39.37 in. [1 m] ID use apan-type distributor with orifices (Model845) or with weirs for fouling services (Model 798).

Flow rate is the next consideration for distributor selection. Trough-type distribu-tors (Model 806) are recommended forseverely fouling services or low flow rateapplications because sealing is more reliable. Deck-type distributors (Model816/916) are best for high flow rates dueto their high cross-flow capacity. Higherflow rates also minimize the adverseeffects of leakage on overall performance.

We offer two enclosed-type distributors(Model 844 and Model 1044). The Model844 is used in non-fouling services whereheight is limited in the feed zone and feedis liquid only. The Model 1044 with spray-style metering arrangement is used forfouling services where the tower’s externalfeed is liquid only. Neither device has anyredistribution capability. However, smallamounts of uniformly-distributed liquid may fall through the distributor from packing above without hydraulic or efficiency problems.

The table shown gives the range of serviceconditions for each distributor model.Special designs may be possible if yourconditions fall outside the parameters listed.

ModelNumber

845

816/817916/917

806

1016/1017

1044

Note: Liquid flow rates vary depending on diameter and gas flow rates; rates shown are typical.Do not confuse rates above with turndown – see specific model number for turndown capability.Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

ColumnDiameterin. [mm]

Liquid Flow Rategpm/ft2 [m3/hr•m2]

AllowableSystem Fouling

Tendency

< 48 [1200]

< 48 [1200]

> 12 [300]

> 36 [900]

> 55 [1400]

1.0 - 30[2.5 - 75]

1.0 - 8.0[2.5 - 20]

0.8 - 50[2.0 - 120]

best for > 10 [25]

2 - 40[5 - 100]

1 -20[2.5 - 50]

Low/Med

High

844

All

1.5 - 10[4 - 25]

798

>17 [430]

0.2 - 50[0.5 - 120]

Low/Med

Low/Med

Low

Low (Slotted)High (“V”)

High(Special)

SELECTION OF TRADITIONAL DISTRIBUTORS

A-12

Page 16: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 845 PAN DISTRIBUTOR

■ Diameters up to 48 in. [1200 mm]

■ Liquid rates between 1 and 30 gpm/ft2 [2.5 – 75 m3/h•m2]

■ Orifices in base

The pan-type construction of the Model845 traditional distributor is designed fortowers less than 48 in. [1200 mm] ID withliquid rates between 1 and 30 gpm/ft2

[2.5 - 75 m3/h•m2]. In towers less than 15 in. [400 mm] ID, one-piece construc-tion, for installation through a body flange,is standard. A special multi-piece construction is available.

Orifices are located in the pan bottom with gas risers set between the orifices. Atdiameters less than 19.7 in. [500 mm], thegas passage may be provided in the gapbetween the pan and the vessel wall,rather than by gas risers.

The standard turndown range is 2.5:1.

For liquid-only feeds to the distributor, usea feed pipe to control feed velocity. Two-phase liquid-vapor feeds require a flashingfeed device to adequately separate phasesand assure proper liquid feed velocity.Refer to “Liquid/Vapor Feed Devices,”Section B, for selection assistance.

The Model 845 is available in any weldablesheet metal, thermoplastic or FRP material.PVC bolting is standard for multi-pieceFRP pans, although there are alternatives.

The Model 845 distributor sits either on afull annular ring or lugs. Distributors withliquid rates below 4 gpm/ft2 (10 m3/h•m2)are gasketed as standard. See Section Gfor ledge and material requirements.

This distributor is not recommended for liquid redistribution; consider using theModel 817 instead.

■ Corrosion allowance (metal only)

■ One-piece construction in columnsgreater than 18 in. [450 mm] indiameter

■ Gasketing for higher flow rates

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Standard design passes through 18 in.[450 mm] nominal manway.

A

B

D

7" - 11"[178 - 279]

Model 845

1 9/16" [40]

A-13

Page 17: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

TulrdpgHlf

FapfaRm

Ara

Trf[

MODEL 798 PAN DISTRIBUTOR

■ Diameters 12 to 48 in.[300 – 1200 mm]

■ Liquid rates between 1 and 8gpm/ft2 [2.5 – 20 m3/h•m2]

■ Weir in riser

he Model 798 “weir riser” distributor issed for highly fouling services in towers

ess than 48 in. [1200 mm] ID. Cylindricalisers with “V” weirs are used as liquidowncomers. A wide turndown range isossible due to the weirs, which allowreater flow as the liquid head increases.owever, maximum liquid flow is severely

imited by the gas flow since they competeor the same passage.

or liquid-only feeds to the distributor, use feed pipe to control feed velocity. Two-hase liquid-vapor feeds require a flashing

eed device to adequately separate phasesnd assure proper liquid feed velocity.efer to “Feed Devices,” Section B forore information.

The Model 798 is available in any weldablesheet metal.

This distributor is supported either by a fullledge or lugs. Gasketing is standard onplates with flow rates less than 4 gpm/ft2 [10 m3/h•m2].

This distributor is not recommended for liquid redistribution. Consider the Model 817 instead.

■ Corrosion allowance

■ One-piece construction in columnsgreater than 18 in. [450 mm] indiameter

CONSTRUCTION DETAILS DESIGN OPTIONS

sk your Saint-Gobain NorPro epresentative about other options t the time of inquiry.

owers less than 18 in. [450 mm] IDequire full diameter access. Distributorsor larger towers pass through an 18 in.450 mm] nominal manway.

Model 798

B

3.9" - 5.5"[100 - 140]

A

C

1 9/16" [40]

B

A-14

Page 18: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 816/817/916/917 DECK DISTRIBUTOR/REDISTRIBUTOR

■ Diameters greater than 12 in. [300 mm]

■ Liquid rates between 0.8 and 50gpm/ft2 [2.0 – 120 m3/h•m2]

■ Orifices in deck

The Model 816 traditional distributors are for towers larger than 10 in. [250 mm]ID with liquid rates between 0.8 and 50 gpm/ft2 [2.5 - 120 m3/h•m2]. The Model817 traditional redistributor has identicalfeatures but is provided with gas riser covers to collect liquid raining from above.

The Model 916 distributor and 917 redistributor are similar to the 816/817,except that the distribution quality hasbeen improved via better pattern and closer attention to point-to-point flow variation. Because of this, however, the height of the plate is not known inadvance of design.

The deck-type construction gives liquidlevel balance around the periphery of thedistributor and at large diameters addition-ally across the mid-span beam. The standard turndown is 2.5:1.

For liquid-only feeds, use a feed pipe andpossibly a parting box. Two-phase liquid-vapor feeds require a flashing feed deviceto adequately separate phases. Refer to “Feed Devices,” Section B, for additionalinformation.

The Models 816/817/916/917 are availablein any weldable sheet metal, thermoplasticor FRP material. The distributor rests on anannular ring with tray clamps.

Distributors in services with liquid ratesbelow 4 gpm/ft2 [10 m3/h•m2] are gasketedas standard. See Section G for ledge andmaterial requirements.

■ Corrosion allowance (metal only)

■ Cross-flow sump

■ Parting boxes (second stage pre-distributor)

CONSTRUCTION DETAILS DESIGN OPTIONS

Tower IDin. [mm]

≤ 47.25 [1200]

> 47.25 [1200]

Model 816in. [mm]

Model 817in. [mm]

8.5 [215]

10.2 [260]

10.0 [253]

13.4 [340] 22.0 [560]

Model 816 or 817With Parting Box

in. [mm]

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

PLATE HEIGHTS (Hd)

Model 916

Model 917

Midspans may be required in towers larger than 10 ft [3000 mm] ID.

Towers less than 18 in. [450 mm] IDrequire full diameter access. Distirbutorsfor larger towers pass through an 18 in.[450 mm] nominal manway with standardconstruction.

A

B

18"[450]

A-15

Page 19: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 806 TROUGH DISTRIBUTOR

■ Diameters greater than 36 in. [900 mm]

■ Liquid rates between 2 and 40gpm/ft2 [5 – 100 m3/h•m2]

■ Weirs in troughs

The Model 806 is a weir-trough distributorfor versatile liquid flow handling capabilityin towers larger than 36 in. [900 mm] ID.This distributor is particularly effective inhandling high liquid flow rates in severelyfouling services.

Model 806 distributors designed for thehighest flow rates employ triangular weirs,also called “V” weirs. Distributors designedfor lower flow rates employ vertical-sidedweirs, also called slotted weirs, for betterflow control.

Liquid is metered to the closed-endtroughs by one or more parting boxes. The number of parting boxes depends onthe tower diameter and liquid flow rate.The normal turndown ratio is 2.5:1. Higherturndown ratios can be achieved with special parting box design.

For liquid-only feeds, use a Model 719feed pipe. Two-phase liquid-vapor feedsrequire a flashing feed device to adequately separate phases. Refer to “Feed Devices,” Section B, for additionalinformation.

The Model 806 distributor is available inany weldable sheet metal, FRP or thermoplastic material. The Model 806rests on a full annular ring. See Section Gfor ledge and material requirements.

This distributor cannot be used as a redistributor. Consider using the Model 817 instead.

■ Corrosion allowance

CONSTRUCTION DETAILS DESIGN OPTIONS

Model 806 distributor with triangular weirsand three parting boxes.

Towers larger than 146 in. [3700 mm] ID may require midspans formetal construction; the maximum span is smaller for other materials.

Standard design of the Model 806 distributor passes through 18 in. [450 mm] nominal manway.

B

Model 806

A

16 1/4" [413]

A-16

Page 20: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

A

T1d[r

FppfsS

Ara

Sd[

MODEL 1016/1017 TROUGH DISTRIBUTOR/REDISTRIBUTOR

■ Diameters greater than 55 in. [1400 mm]

■ Liquid rates between 1 and 20gpm/ft2 [2.5 – 50 m3/h•m2]

■ Orifices in troughs

he Model 1016 distributor and Model017 redistributor are trough-type istributors for towers greater than 55 in.

1400 mm] ID. The standard turndownange is 1.8:1.

or liquid-only feeds use a feed pipe andossibly parting box construction. Twohase feeds (liquid and vapor) require a

lashing feed device to adequately eparate phases. Refer to “Feed Devices,”ection B, for more information.

The Models 1016/1017 are available in any weldable sheet metal. Distributors withliquid rates below 4 gpm/ft2 [10 m3/h•m2]are gasketed as standard. See Section Gfor ledge and material requirements. Thisdistributor rests on an annular ring.

Standard design for a Model 1017 redistributor includes a wall wiper weldedto the tower wall and gas riser covers tocollect and redistribute liquid raining downfrom above.

■ Corrosion allowance

■ Cross-mixing (Model 1017 only)

■ Orifice strainers

■ Leveling screws

CONSTRUCTION DETAILS DESIGN OPTIONS

sk your Saint-Gobain NorPro epresentative about other options t the time of inquiry.

tandard design of the Model 1016/1017 istributor passes through 18 in.

450 mm] nominal manway.

Model 1016

Height varies with turndown.

Model 1017

A

B

12"[300]

18"[450]

-17

Page 21: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 844 PIPE-ARM DISTRIBUTOR

■ Diameters larger than 17 in. [430 mm]

■ Liquid rates between 1.5 and 10 gpm/ft2

[4 – 25 m3/h•m2]

The Model 844 liquid distributor requireslittle column elevation to accomplish itsdistribution task, and it provides high open area for high vapor flow. The Model844 should be used only with clean liquidsor with a filter designed to remove any particles that could block the orifices.

The standard design of the Model 844handles liquid rates up to 10 gpm/ft2

[25 m3/h•m2], but special designs can handle higher rates. The normal turndownratio for the Model 844 is 2.5:1.

The Model 844 is available in any weldablemetal pipe or thermoplastic material. Thelaterals are removable to permit passagethrough vessel manways. The header section is flanged for standard horizontalfeed from the side of the tower. Inlet flangemates to a 150 pound flange. See SectionG for material requirements.

This distributor can be used to redistributeliquid from a liquid collector plate above it.See “Liquid Collectors,” Section E, formore information.

■ Flanged laterals

■ Corrosion allowance (metal only)

■ Vertical-feed header, on tower centerline

■ Bayonet-style construction for smalltowers (type I or II metal, type II plastic – see Section G)

■ Threaded header

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

The Model 844 passes through 18 in.[450 mm] nominal manway.

Lateral may require support by customer

Model 844

B

A

TOWER CENTERLINE

INTERIOR FLANGEBY CUSTOMER

SUPPORT SADDLEBY CUSTOMER

A-18

Page 22: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 1044 SPRAY-TYPE LIQUID DISTRIBUTOR

■ Liquid rates between 0.2 and 50 gpm/ft2

[0.5 – 120 m3/h•m2]

The Model 1044 spray-type distributor isan inexpensive distributor used over shallow beds of packing in heat transferservice. It can be designed for very low liquid rates because each spray nozzlecovers a large area of the tower, so eachnozzle passes a reasonable flow, even atlow irrigation rate. The normal turndownratio is 2:1.

The Model 1044 is available in any weldable metal for which pipe and flangesare readily available. The laterals areremovable for manway passage. Theheader section is flanged for the feed nozzle connection; a 150 pound internalfeed flange is expected.

■ Corrosion allowance

■ 300 pound flanges

■ Double or triple coverage patterns

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 1044

A

B

VARIES

TOWER CENTERLINE

INTERIOR FLANGEBY CUSTOMER

WALL CLIP(S)BY CUSTOMER

A-19

Page 23: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

FEED DEVICES

Obtaining desirable tower performancerequires the proper handling of liquid andvapor entering the column. The types offeeds, or inlets, into a column can generallybe classified into four major categories:

■ Liquid only (contains less than 1%volume vapor)

■ Liquid and vapor above a packedbed (flashing or suppressed flash)

■ Vapor only below a packed bed

■ Reboiler returns

Selection criteria for each category of feeddevice is unique. The following tablesassist in selecting the proper equipment.

The selection of liquid-only feed devices,which are required as pre-distributors,depends on the type of distributor and onturndown needs. Among the factors Saint-Gobain NorPro considers in designing a feed device are flow rate,operating range, degree of sub-cooled liquid versus column size and temperature,and whether mixing with overhead liquid is required.

For liquid and vapor feed devices above adistributor (Table II), the selection dependson the type of distributor, flow rates, typeof flow at feed (flashing or suppressed),turndown necessary, column height needed for flashing vapor distribution andmixing of the inlet liquid with the overheadliquid. In all cases, separating the twophases is a primary concern. Additionalpre-distribution (via parting boxes) may be required.

Model

119

129

719

Used WithType Distributor

Intalox

Intalox

Traditional

729 Traditional

TurndownRatio

≤ 2:1

≤10:1

≤ 2.5:1

≤ 10:1

Model Flow RegionTower Size

in. [mm]

755

855

955

Any

Any

Separated

> 36 [900]

< 48 [1200]

> 48 [1200]

192* Spray orSeparated

> 96 [2400]

655* Any > 60 [1500]

SELECTING A LIQUID ONLY FEED PIPE

(Inlet is less than 1% volume vapor)

SELECTING A LIQUID/VAPOR FEED PIPE

(Inlet is more than 1% volume vapor)

Table I

Table II

*See page G-4 for general description

B-1

Page 24: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

Two factors must be considered in choosing the proper device for a vaporonly feed below a packed bed (Table III).

1. Kinetic energy of inlet vapor

The kinetic energy of the inlet vapor mustbe considered in relation to the pressuredrop in the packed bed, the feed nozzlearrangement and tower separation requirements.

2. Vapor composition

When the vapor is introduced betweenpacked beds, consider the degree of mixing of the inlet vapor with the risingvapor. If a gross mismatch of compositionand/or temperature exists, mixing of thetwo vapors optimizes packing perform-ance above.

Specific equipment for vapor distributionmay not be required if the pressure drop in the packed bed is sufficient for propervapor distribution.

To determine the type of feed devicerequired for a reboiler return, the first stepis to consider the kinetic energy asdescribed above. After it is determined that vapor distribution is required, factorsto consider include feed nozzle size andarrangement, pressure drop in the packedbed, flow rates, tower size and type ofreboiler.

If vapor distribution equipment is neededabove reboiler return inlets, the Model 896is an effective distributor. Occasionalexceptions are listed in Table IV.

For those towers employing suppressedvaporization reboilers, the pressure releaseand flash should not occur at the towernozzle. The Model 144 suppressed flashdistributor is effective for these towers.

Model

194*

198

796*

Typical UseTower Size

in. [mm]

Vapor Diffuser

Vapor Distributor(For Uniform Flow/Mixing)

Vapor Distributor(for Uniform flow)

> 48 [1200]

> 17 [430]

All896 Vapor Distributor(for Uniform flow)

> 48 [1200]

196 Vapor Diffuser(Reduces Flow Inertia)

> 48 [1200]

UsualModel

896

896

896

AlternateModelsType Reboiler

796*

196, 796*

Thermosiphon

Forced Circulation

Kettle-type

896, 796*Suppressed Flash 144*

796*

SELECTING VAPOR ONLY FEED DEVICES

SELECTING REBOILER RETURN FEED DEVICES

(IF VAPOR DISTRIBUTION EQUIPMENT IS NEEDED)

*See page G-4 for general description

Table III

Table IV

B-2

Page 25: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 119/129 LIQUID ONLY FEED PIPE

The Models 119 and 129 liquid only feedpipes are used when liquid is fed from outside the column onto a NorPro Intaloxdistributor or redistributor. Each feed pipemeters flow to one or more appropriatefeed areas, matching the hydraulic requirements of the distributor. Excessiveturbulence and horizontal flow velocity inthe distributor are eliminated in a compactdesign.

The Model 119 feed pipe is a piping system of headers, lateral branches, anddownpipes. It is limited in turndown to a2:1 ratio or perhaps slightly more. TheModel 129 feed system employs a partingbox or calming boxes below simpler piping. It can handle much higher turndown ratios than the Model 119, but itmay require slightly more tower height.

A submerged feed is recommended whenthe liquid is sub-cooled more than 30° F[17° C] in large towers with low flow rates.Submerging the feed maintains uniform liquid temperature from the distributor andmay also be used in cases where a morecompact design is required.

The Model 119/129 is available in anyweldable metal, FRP or thermoplasticmaterial.

With the standard vertical system design,the Model 119/129 attaches to an internalcolumn flange and is further supported bytower wall clips. The submerged style does not require tower wall clips and issupported by the distributor.

■ Corrosion allowance (metal only)

■ Bayonet-style construction – seeSection G

■ All-flanged construction, (eliminatesinternal threaded connectionsexcept with some bayonets)

■ Submerged feed

■ Support from liquid distributor

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 119

Model 129

A

C

VARIES

OPTIONAL PARTING BOX

B-3

Page 26: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 719/729 LIQUID ONLY FEED PIPE

The Models 719 and 729 liquid only feedpipes are used when liquid is fed from outside the column onto a traditional distributor or redistributor. The incomingflow must contain less than 1% by volumevapor.

The Model 719 feed pipe is a piping system of headers and downpipes. It canprovide a turndown ratio up to 2.5:1. TheModel 729 feed system employs a partingbox below simpler piping. It can handlemuch higher turndown ratios than theModel 719, but it usually requires slightlymore tower height.

The Models 719/729 are available in anyweldable metal, FRP or thermoplasticmaterial in pipe or tubular form. With thestandard design, feed pipes attach to theinternal column flange and are supportedby tower wall clips. As an option, the feed pipe can be supported from the distributor.

■ Corrosion allowance (metal only)

■ Bayonet-style construction – seeSection G

■ All-flanged construction, (eliminatesinternal threaded connectionsexcept with some bayonets)

■ Support from liquid distributor

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 719

Model 729

A

C

VARIES

OPTIONAL PARTING BOX

B-4

Page 27: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 755 FLASHING FEED GALLERY

The Model 755 flashing feed gallery is atwo-phase feed device fed by a tangentialinlet tower nozzle or a radial nozzle with aflow deflector (shown below). Incomingflow is directed tangentially onto the towerwall. A gallery below the inlet collects liquidinto a pool, allowing the vapor or gas todisengage. The liquid then falls directly to adistributor or into a pre-distributor (partingbox). The Model 755 is recommended intowers 36 in. [900 mm] ID and larger andhandles any liquid to vapor feed ratio.

The Model 755 is available in any weldablemetal. The inside of the gallery may beround or polygonal. The gallery is clampedto a ledge as standard attachment.

■ Inlet deflector attached to inlet nozzle internal flange

■ Joint gasketing

■ Corrosion allowance

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Flow deflectors are supplied by others.They can be uni- or bi-directional.

Model 755

A

B

Hd Hn

B-5

Page 28: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

B

Ttttvbitlo

Tttlba

Ara

MODEL 855 FLASHING FEED CHAMBER

he Model 855 flashing feed chamber is awo-phase feed device which is attachedo a radial inlet. The feed is centrifuged inhe chamber, separating the phases —apor out the top and liquid out the ottom to a distributor below. This model

s used with either a NorPro Intalox or raditional distributor or redistributor. Theiquid falls either directly to a distributor r into a pre-distributor.

he Model 855 is recommended for owers up to 48 in. [1200 mm] ID on mostwo-phase feeds. This device handles alliquid to vapor ratios. Larger towers mayenefit from use of this device if flow ratesre suitable.

The Model 855 is available in any weldablemetal. For towers between 10.12 and21.14 in. [250 - 530 mm] ID, the Model855 is constructed in one piece; multi-piece construction is used for larger tow-ers.

With inlet pipe sizes less than 4 in. [10 mm], the Model 855 has a threadedconnection to a bayoneted inlet pipe sup-plied by others as standard. Larger inletpipe sizes are flanged as standard.

■ Corrosion allowance

■ Bayonet construction — see Section G

CONSTRUCTION DETAILS DESIGN OPTIONS

sk your Saint-Gobain NorPro epresentative about other options t the time of inquiry.

Model 855

A

C

Hd

-6

Page 29: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 955 FLASHING FEED PIPE

The Model 955 flashing feed pipe is usedto separate a two-phase feed when theinlet flow is in a separated flow region. With the Model 955, the two-phase flowenters the center pipe. The vapor isreleased from the upper area of the pipeand the liquid flows to the outer chamberwhere it is metered to desired points onthe distributor below.

This model is most often used for vacuumservices in towers larger than 48 in. [1200 mm] ID. The compact design of thismodel makes good use of tower height.

The Model 955 is available in any weldablemetal. The Model 955 is connected to aninternal tower flange and is further support-ed by a tower wall clip as standard. Thedevice is constructed in one piece, provid-ed access diameter is sufficient.Otherwise, multi-piece construction withgasketing is supplied.

■ Corrosion allowance

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 955

TOWER I.D.

C

VARIES

B-7

Page 30: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 196 VAPOR DIFFUSER

The Model 196 vapor diffuser is usedwhere the incoming flow is vapor only andthe flow energy is excessive, causing vapormaldistribution to the bed above. Thisdevice reduces the flow inertia, whichallows proper distribution. The Model 196is not a vapor distributor; see Model 198.

The Model 196 meters the vapor uniformlyout the upper area of the tube and theshroud, then directs it down each side ofthe tube. Pressure drop across this deviceis relatively low compared to the Model198. The vapor flow turndown ratio is generally 4:1; however, higher ratios arepossible. The Model 196 is used in towerslarger than 48 in. [1200 mm] ID.

The Model 196 is available in any weldablemetal. This model is attached to an internaltower flange and is further supported by atower wall clip as standard construction.Optionally, the inlet end can be made tosleeve into the vapor inlet nozzle in lieu of an internal tower flange. One-piece construction is standard provided accessdiameter is sufficient. Otherwise, multi-piece construction is supplied.

■ Sleeve inlet (eliminates internalflange, but may require extra weld-on wall clips)

■ Corrosion allowance

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 196

A

C

VARIES

B-8

Page 31: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 198 VAPOR DISTRIBUTOR

The Model 198 pipe arm vapor distributoris used when the feed requires uniform dis-tribution over the tower area. Typical appli-cations include introduction of a vapor feedat the bottom of the tower into a very tightspace or introduction of a vapor which dif-fers in composition or temperature andneeds mixing with the column vapor.

The maximum vapor rate may be limiteddue to the amount of tower area occupiedby the device. Required pressure dropacross the distributor to achieve properdistribution is determined by size of theinlet and flow rate. Turndown ratio is gen-erally 4:1; however, higher ratios are possi-ble provided the pressure drop is notexcessive for the process. This device canbe used in towers larger than 17 in. [430 mm] ID.

The Model 198 is available in any weldablemetal or thermoplastic pipe material. Thelaterals are threaded in pipes 3 in. [75 mm] or less and flanged in larger sizes.The access diameter must be sufficient toaccommodate the header. The headersection is flanged at the inlet end and isfurther supported by wall clips. Lateralpipes are also supported by wall clips ontowers larger than 96 in. [2400 mm] ID.Plastic construction may require addedsupport in smaller towers.

■ Flanged laterals

■ Corrosion allowance (metal only)

■ Bayonet-style construction for smalltowers (type I or II metal, or type IIplastics — see Section G)

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 198

A

C

B-9

Page 32: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 896 VAPOR DISTRIBUTOR PLATE

The Model 896 vapor distributor plate isused above vapor-containing tower feedsto assure good vapor distribution to thepacked bed above.

Most packed beds do not need vapor distributors. These beds include bedsreceiving vapor from other packing, liquiddistributors, or liquid collectors below.Beds receiving vapor from low-velocity-head feeds also do not need vapor distributors. The vapor distributors arenecessary below beds receiving a largefraction of their vapor from high-velocity-head external feeds.

In performing its vapor distribution task,the Model 896 will consume some pressure drop in the vapor. The designpressure drop will be between 0.5 and 4 in. water [125 - 1000 Pa].

The turndown ratio of the Model 896 is atleast 4:1.

The Model 896 is available in any weldablesheet metal. It is supported by an annularring and perhaps by midspan beams inlarge towers. The Model 896 is gasketed;see Section G for ledge and materialrequirements.

■ Corrosion allowance

■ Liquid downpipes or sumps

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 896

A B

Ha

Hd

B-10

Page 33: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

W

R

Fbifod

U

Tubw

TApAiTt

Araddbdtuogcmapa

BED LIMITERS

hen are bed limiters required?

andom Packing

or metal and plastic random packings,ed limiters are recommended when there

s the potential for sufficient vapor load toluidize the top of the bed. Generally, thisccurs during upset conditions, which areifficult to predict.

se the table below for guidelines.

here are three basic ways to preventpward movement of random packing:ed limiters, anti-migration bars andeighted plates.

he bed limiter is the most common type. bed limiter either sits directly on theacking or is attached to the vessel wall.ttachment to the vessel wall increases

nterference with the distribution pattern.he bed limiter acts as a screen to confinehe packing to the defined bed.

nother method of retaining a bed of andom packing is through the use of nti-migration bars at the bottom of theistributor’s gas risers. Anti-migration barso not prevent the packed bed fromecoming fluidized and unleveled, but theyo prevent packing from being blown uphrough the gas risers. The concern in these of anti-migration bars is the possibilityf restricting vapor passage through theas risers. This could lead to liquid back-ycling due to high vapor velocity, whichay flood the distributor. Hence, close

ttention to process and internal designarameters is recommended before usingnti-migration bars.

The Model 905 is a weighted plate usedwith ceramic or carbon tower packing toprevent breakage. It is important to levelthe bed to assure packing contact with thehold-down plate over all areas. In additionto handling vapor surges, weighted platesare recommended when liquid rates aregreater than 15 gpm/ft2 [35 m3/h•m2].

Structured Packing

Bed limiters are recommended for use withstructured packing when there is thepotential for packing displacement duringupset conditions. Retention of the top layeris accomplished with the Model 133,which may be attached to the distributor.For towers with one-piece layers of pack-ing, the Model 133 is typically integral withthe distributor to provide a means of sup-port for and attachment to the distributor.

Many columns with structured packing donot need bed limiters.

Bed Limiter Selection

Bed limiters must maintain a high free areafor vapor/liquid passage and minimizeinterference with liquid distribution. WithIntalox distributors, non-interfering bed lim-iters such as the Models 103 and 133 arerecommended. The Model 822 is speciallydesigned for use on top of random pack-ing with a spray distributor (Model 1044)above.

When laying out tower elevations, the bedlimiter is not considered part of the packedbed. The top of the packed bed is normallysix to eight in. [150 - 200 mm] from thedistributor to allow for gas disengagementfrom the packed bed. The bed limiteroccupies this disengagement area.

The table below summarizes the selectioncriteria for any size tower. The supportmethod is given in reference to vessel wallattachments. See the appropriate modeldescription for further details.

*Pressure drop is difficult to predict in flood.

Packing Wt.(lbs/ft3)

5 10 15

∆P(in. WC/ft)

1.92 3.8*

20

4.8*

25

0.96 2.9*

*Contact Saint-Gobain NorPro for plate details

WallAttachment

PlateConstruction

MaterialType ofPacking

PackingConstruction

Material

None; restson packing

Metalor Plastic

Metalor Plastic

Metal

Metal

Random

Random

Structured

Random

Random

Metalor Plastic

Metalor Plastic

Metal

Metalor Plastic

Ceramicor Carbon

Metal

ModelNumber

103

823

133

822*

905*

Attached tosupport ring

Attached towall clips

Attached tosupport ring

None; restson packing

APPROXIMATE POINT OF FLUIDIZATION

SELECTING A BED LIMITER

C-1

Page 34: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 823 BED LIMITER FOR RANDOM PACKING

When traditional metal or plastic randompackings are used, the Model 823 is fixedto the tower wall. The standard method offastening the bed limiter to the vessel wall is by clamps to a ledge welded in the column.

The Model 823 is available in any weldablemetal or thermoplastic material in sheetform.

For metal construction, the plate can withstand 50 lbs/ft2 [250 kg/m2] uniformupward force. Towers up to 36.22 in. [900 mm] ID are furnished with either ledgeclamping or jack screws. The plate screenon the opening may vary depending onpacking size.

For thermoplastic construction, the platecan withstand 5 lbs/ft2 [25 kg/m2] uniformupward force. All plates are clamped to thesupport ledge as standard.

■ Greater upward force

■ Corrosion allowance (metal only)

■ Jack screws on plates smaller than36.22 in. [920 mm]

CONSTRUCTION DETAILS DESIGN OPTIONS

Material

Metal

Polypropylene

CPVC

lbs./ft2 kg/m2

3.3

1.2

1.8

16.2

5.9

8.8

Note: Other materials are available.

APPROXIMATE WEIGHT

A B

3" - 5"

[75 - 125]

Model 823

C-2

Page 35: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 103 NON-INTERFERING BED LIMITER FOR RANDOM PACKING

The Model 103 bed limiter is designed to minimize interference with liquid distribu-tion below an Intalox liquid distributor. Thebed limiter diameter is expandable to per-mit contact with the vessel wall, whicheliminates the need for wall attachmentsand prevents random packing from escaping.

The Model 103 is available in any weldablemetal or thermoplastic material. The stan-dard minimum access diameter requiredfor the Model 103 is 17 in. [430 mm].

With metal construction, standard designcan withstand 50 lbs/ft2 [250 kg/m2] uniform upward force.

The thermoplastic Model 103 can withstand 10 lbs/ft2 [50 kg/m2] upwardforce.

■ Corrosion allowance (metal only)

■ Greater upward force

CONSTRUCTION DETAILS DESIGN OPTIONS

Material

Metal

Polypropylene

CPVC

lbs./ft2 kg/m2

3.0

1.1

1.6

14.7

5.4

7.8

Note: Other materials are available.

APPROXIMATE WEIGHT

Model 103

Tdpddvlwp

he Model 133 metal bed limiter isesigned for use with Intalox structuredacking or Intalox wire gauze packing. Itsesign minimizes interference with liquidistribution. This bed limiter is bolted to theessel wall by means of vertical clips inarger towers. The Model 133 is integralith the distributor when restricting one-iece packing layers.

The Model 133 is available in any weldablesheet metal. This plate will pass throughany standard manway.

The standard design can withstand 50 lbs/ft2 [250 kg/m2] uniform upward force.

■ Jack screws on plates smaller than36 in. [920 mm]

■ Corrosion allowance

■ Attachment to the distributor

■ Support for the distributor

■ Greater upward force

MODEL 133 BED LIMITER FOR STRUCTURED PACKING

CONSTRUCTION DETAILS DESIGN OPTIONS

Model 133

C-3

Page 36: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

SUPPORT PLATES

Saint-Gobain NorPro manufactures support plates for random and structuredtower packings. Regardless of the packing, each plate incorporates severalcritical design factors. First, the plate mustphysically support the packing under operating conditions. Second, it must havea high percentage of free area to allowunrestricted flow of downcoming liquid andupward flow of gas. Third, it must be easyto install.

There are several criteria for selecting asupport plate:

■ Type of packing supported (random or structured)

■ Process characteristics (corrosion,packing material, temperature)

■ Maximum design load supported(bed depth, packing type and material, liquid hold-up, materialbuild up in the bed and surge conditions)

Note: In cases where the column liquidlevel rises above the vapor entry, the support plates can be subjected to exceptional forces.

Pressure drop calculations for our towerpackings include the pressure dropthrough support plates of our design: Noextra pressure drop need be added for thesupport plate. Support plates can bedesigned to handle any liquid flow rate. In both cases (pressure drop and liquidrates), the packing is the limiting factor in tower design.

■ A random-packed bed depthincludes the height of the supportplate. A structured-packed beddepth does not include the height of the support.

Where tower height is a premium, specialdesigns for support plates are available to permit integral packing support and either vapor distribution or partial liquid collection.

Gas injection support plates are designedto provide separate passageways for gasand liquid so both phases do not competefor the same opening. Unrestricted flow ofboth phases minimizes pressure dropacross the plate. This is done by providinggas inlets above the liquid head, preventingexcess liquid build-up. The support platesare designed to retain the various packingsizes while not restricting the capacity ofthe packing.

Support plates for random packingsinclude the Models 809 light-duty support,

818 support, and 804 multi-beam support.All are made of metals; the Models 818and 804 are also available in thermoplastic.The Models 819 and 1019 are both available in FRP only.

Supporting a structured packing is somewhat simpler than supporting random packing because the integralnature of the structured packing physicallyallows support by an open grid. The majordesign criteria is minimization of the gridcross-sectional area while providing sufficient strength. The Model 134 support for structured packing is available in metal only.

All our support plates sit directly on anannular ring. The weight of the packed bed is normally sufficient to keep the platein place. However, if extra restraint isneeded, the plate can be clamped to itssupport ring.

Contact your local Saint-Gobain NorPro representative for applications outside the “standards”shown in this brochure.

ModelNumber

Tower IDin. [mm]

Type PackingSupported

ConstructionMaterial

818

809

804

819

1019

< 48 [1200]

> 48 [1200]

Any Random

Random (light)

Any Random

Random(except ceramic)

Random(except ceramic)

Metals andThermoplastics

Metals

Metals andThermoplastics

FRP

FRP

> 36 [900]

< 48 [1200]

< 35.25 [890]

Any Structured134 Metal

SELECTING A SUPPORT PLATE

D-1

Page 37: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 818 GAS INJECTION SUPPORT PLATE

Because the Model 818 support platecombines high free area with excellentmechanical strength, it is generally recommended for all towers less than 36 in. [900 mm] ID. This support incorporates the multi-beam design principle into two- or three-pieced unitsfor towers ranging from 12 to 48.62 in.[305 - 1235 mm] ID.

Metal plates can support loads up to 1000 lbs/ft2 [4800 kg/m2] or more. Thetable below provides allowable load valuesfor different thermoplastic materials at various temperatures.

The Model 818 is available in any weldablesheet metal or thermoplastic material.These plates are supported by a full ledge.See Section G for ledge and attachmentrequirements.

Two-piece construction is provided fortowers between 12 in. and 34 in. [305 - 865 mm] ID. Three or four-piececonstruction is provided for towersbetween 34.1 and 48.62 in. [866 - 1235 mm] ID.

State the size of packing at the time ofinquiry.

■ Corrosion allowance (metal only)

■ One-piece construction in all sizes

■ Heavy-duty construction (thermoplastic only)

■ Ledge clamping

CONSTRUCTION DETAILS DESIGN OPTIONS

Material

Metal

Polypropylene

CPVC

lb/ft2 kg/m2

5.5

2.4

4.1

26.9

11.7

20.0

Note: Other materials are available.

APPROXIMATE WEIGHT

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Curve Plastic

1 PVC/CPVC @ 75° F [24° C] through 125° F [52° C]

2 Polypropylene @ 75° F [24° C]

3 Polypropylene @ 100° F [38° C]

4 Polypropylene @ 125° F [52° C] orPVC/CPVC @ 150° F [66° C]

5 Polypropylene @ 150° F [66° C]

400 600

1000

500

750

1250

300

250

200

150

100

50

0

12 18 24 30 42 48

(inches)

(lb/f

t2)

(kg

/m2 )

250

(millimeters)

36

500 700 800 900 1000 1100 1200

12345

Allo

wable

Load

Tower ID

MAXIMUM ALLOWABLE LOAD - PLASTICS

Note: Standard heavy-dutyconstruction increases loadcapacity 1.25 times. Highertemperatures and/or loadsare possible.

Model 818

A B

4 1/2" [114]

D-2

Page 38: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

D

TriTsmpvaSs

MODEL 804 GAS INJECTION SUPPORT PLATE

he Model 804 support plate is ecommended to support random packingn towers greater than 36 in. [900 mm] ID.he Model 804 is recognized as the typicaltyle due to its high open area andechanical strength. The table below rovides the maximum allowable load alues for different thermoplastic materialst various temperatures. Contact aint-Gobain NorPro for maximum pans when using metal.

The Model 804 is available in any weldablesheet metal or thermoplastic material. See Section G for ledge and materialrequirements.

Thermoplastic supports retain #40 IMTP®

packing, 2 in. [50 mm] saddles or ³⁄₄ in. [19 mm] and larger rings. Contact yourSaint-Gobain NorPro representative ifsmaller packing must be supported.

All beams can be installed through manways 16 in. [406 mm] ID and larger.The plate is supported by a full ledge onwhich it typically rests freely.

■ Corrosion allowance (metal only)

■ Heavy-duty construction (thermoplastic only)

■ Beam to beam clamps

■ Ledge clamping

CONSTRUCTION DETAILS DESIGN OPTIONS

Material

Metal

Polypropylene

CPVC

lb/ft2 kg/m2

6.0

2.4

4.1

29.3

11.7

20.0

Note: Other materials are available.

APPROXIMATE WEIGHT

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Curve Plastic

1 PVC/CPVC @ 75° F [24° C] through 125° F [52° C]

2 Polypropylene @ 75° F [24° C]

3 Polypropylene @ 100° F [38° C]

4 Polypropylene @ 125° F [52° C] orPVC/CPVC @ 150° F [66° C]

5 Polypropylene @ 150° F [66° C]

1000 1500

1000

2000

500

750

1250

300

250

200

150

100

50

0

36 48 60 72 84 96

(inches)

(lb/f

t2)

(kg

/m2 )

250

(millimeters)

12

345

Tower ID or Span

Allo

wable

Load

MAXIMUM ALLOWABLE LOAD - PLASTICS

Note: Standard heavy-dutyconstruction increases loadcapacity 1.25 times. Highertemperatures and/or loadsare possible.Contact you Saint-GobainNorPro representative formaximum metal spans.

A B

VARIES

Model 804

-3

Page 39: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 809 LIGHT DUTY SUPPORT PLATE

The Model 809 support plate is availablefor towers between 4 and 35.25 in. [100 - 895 mm] ID supporting metal,ceramic or plastic random packings. Thiscorrugated support plate should be usedonly when:

■ Bed height is limited

■ Hydraulic loading is not severe

■ Small packings (¹⁄₂ in. or 13 mm) areused in towers greater than 11.7 in.[300 mm] ID

In other cases, consider use of the Model818 as an alternative.

The Model 809 is available in any weldablesheet metal. Two piece construction isstandard .

The Model 809 retains #15 IMTP packingor ¹⁄₄ in. [6 mm] and larger saddles andrings.

■ Ledge clamps for towers greaterthan 12 in. [300 mm] ID

■ Corrosion allowance

■ One-piece construction

CONSTRUCTION DETAILS DESIGN OPTIONS

Temperature°F [°C]

300 [149]

400 [204]

500 [260]

600 [316]

Carbon Steel Stainless

0.983

0.957

0.856

0.729

0.917

0.835

0.732

0.777

700 [371]

800 [427]

This table provides correction factors based on maximumoperating temperatures. Multiply allowable load from thecurves by the correction factor to obtain maximumallowable load during operation.

0.627

NR

0.719

0.686

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

ALLOWABLE LOAD

CORRECTION MULTIPLIER

250 750

3000

2000

2500

3500

800

700

600

500

400

300

200

(inches)

(lb/f

t2)

(kg

/m2 )

1500

(millimeters)

500

1000

500100

06 1812 24 30

Tower ID

Allo

wable

Load

MAXIMUM ALLOWABLE LOAD

Note: Corrosion allowanceis not factored into eithercurve. materials are carbonsteel, 304L and 316Lstainless steel. Contactyour Saint-Gobain NorProrepresentative for allowableloads for other materials.

A B

1" - 1 1/2

[25 - 38]

Model 809

D-4

Page 40: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 819/1019 FRP GAS INJECTION SUPPORT PLATE

Both Models 819/1019 use beam-typeconstruction similar to that of the Model804. The Model 819 is designed for towersbetween 18 and 48 in. [450 - 1200 mm] IDwhile the Model 1019 support plate isdesigned for towers greater than 48 in.[1200 mm] ID.

Use the allowable load graph below to calculate the maximum length of the beam to support the packed bed plus liquid hold-up. If your actual loads are higher than those included in the graph,contact your Saint-Gobain NorPro representative about a special design.

The Models 819/1019 are available in FRPonly. See Section G for material and ledgerequirements.

Each model retains 2 in. [50 mm] saddlesor 1 in. [25 mm] and larger rings. Contactyour Saint-Gobain NorPro representative ifsmaller packing must be supported. FRP construction is not recommended for use with ceramic packings.

The approximate weight for the Model 819is 4.75 lbs/ft2 [23 kg/m2]; for the Model1019, 6 lbs/ft2 [29 kg/m2]. Beams can beinstalled through a 7.5 in. [190 mm] IDhandhole for the Model 819, and through a 17 in. [430 mm] ID manway for theModel 1019.

This plate is supported on a full ledge.Large plates may require midspans.

CONSTRUCTION DETAILS

Temperature°F [°C]

100 [38]

125 [52]

150 [66]

175 [80]

0.948

0.908

0.867

0.827

Multiplier

200 [93]

225 [107]

0.787

0.746

0.706250 [121]

This table provides correction factors onmaximum operating temperatures.Multiply the allowable load from thecurves by the correction factor to obtainthe maximum allowable load duringoperation.

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

1000 2000

1000

500

1500

400

350

300

250

200

150

100

(inches)

(lb/f

t2)

(kg

/m2 )

(millimeters)

1500

50

0

18 4230 54 66 78 90 96847260483624

Tower ID or SpanFor Standard Design Ratings

Allo

wab

le L

oad

819 1019

68°

F [2

0° C

]

ALLOWABLE LOAD

CORRECTION MULTIPLIER

A

B

VARIES

Model 1019

D-5

Page 41: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 134 SUPPORT GRID

The Model 134 is used to support eitherIntalox structured packing or Intalox wiregauze packing. Design of the support gridallows free and uniform passage of gasand liquid so that capacity of the packingis not limited.

The Model 134 is available in any weldablesheet metal. The approximate weight ofthe grid is 14 lbs/ft2 [68 kg/m2]. Grids canbe installed through a 17 in. [430 mm] IDmanway.

This plate is supported on a full ledge.Larger plates may require midspan beams.Lightly loaded plates can span up to 14 ft[4270 mm] without beams, but heavilyloaded plates at high temperature mayneed beams at 10 ft [3050 mm] diameter.

■ Ledge clamps

■ Corrosion allowance

■ Lower height requirement Hd

CONSTRUCTION DETAILS DESIGN OPTIONS

Tower Diameterin. [mm]

Maximum HeightHd, in. [mm]

≤ 39.37 [1000 ]

39.37 to 72.25 [1835 ]

> 96.46 [2450 ]

3 [75 ]

4 [100 ]

5 [125 ]72.26 to 96.45 [2450 ]

6 [150 ]

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

A

B

Hd

Model 134

D-6

Page 42: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

LIQUID COLLECTORS

Liquid collection from between packedbeds is frequently required. Liquid collectors are used in three main circumstances:

■ Total draw-off of liquid to product orreboiler or pump-around/pump-down

■ Partial draw-off of liquid with overflow continuing down the tower

■ Collection of liquid for mixing

Collector plates come in different designstyles which meet the needs of specificapplications. For example, chevron- andtrough-style collector plates require lesstower height than deck-style collectors andthus are better suited for applicationswhere packed height is limited.

The chevron style of the Model 633 makesthis design suitable for high vapor rates, asare typical of vacuum applications.Applying chevrons in towers less than 31.5 in. [800 mm] ID is impractical. Thedeck-type Model 833 can be used insmaller diameter towers where the Models 633 and 733 cannot. Deck-styleconstruction is versatile at handling highliquid rates. However, thermoexpansioncan present leakage problems for a largedeck-type collector. In these cases, thetrough-type Model 733 is recommended.The troughs eliminate the need to seal thecollectors to a ledge. The collector plate’sliquid capacity can be varied by sump and riser design.

The table below is helpful in selecting the appropriate model for various applications.

Model

633

733

833

StyleTypical

Open AreaTypical

Application

Chevron

Trough

50 - 80%

25 - 40%

25 - 40%

High Vapor Rates& Low Liquid Rates

Thermoexpansionwith Low to High

Liquid Rates

All Liquid RatesDeck

SELECTING A LIQUID COLLECTOR

E-1

Page 43: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 633 CHEVRON-TYPE LIQUID COLLECTOR

The Model 633 is used in towers that aregreater than 31.5 in. [800 mm] ID and thatprocess high vapor loads and low liquidloads (vacuum service). The plate collectsoverhead liquid which is drawn from thetower or fed to a distributor below. Theplate consumes minimal pressure drop andit avoids entrainment even at vapor rateshigh enough to cause entrainment fromconventional gas risers.

The size of the sump varies, depending onthe hydraulic needs of each application.The collector has approximately 50% openarea in small towers and up to 80% in larg-er towers. In applications where liquid isdirectly fed to a distributor below, a feedpipe is required to properly feed the distributor below.

The Model 633 is available in any weldablesheet metal. Standard construction has thechevrons resting on an annular sumpwelded to the tower wall. The annularsump in new towers is generally part of thevessel and only the chevrons are suppliedby Saint-Gobain NorPro. For larger towersand high liquid rates, collection trough(s)are added, spanning across the annularsump. These troughs shorten the flow path length of the liquid collected in the chevrons.

■ Corrosion allowance

■ Supply of annular sump

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 633

A

B

Hd

E-2

Page 44: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 733 TROUGH LIQUID COLLECTOR

The Model 733 is used for a wide variety of applications in towers greater than 55 in. [1400 mm] ID. The Model 733 isgenerally the best choice in larger towerswhere thermoexpansion is a concern. Thetrough arrangement minimizes welding tothe vessel wall. The troughs are free toexpand because they rest on the ledge. A wall wiper directs liquid to the troughs.

The center sump is usually sealed to a seat at only one end, where the liquid isdrawn from the tower, which frees theopposite end to expand and contract.

The sump sizes and trough are designedto suit the application needs. This model is used for either total or partial liquiddraw-off. Applications where liquid is fed to a distributor below require a feed pipe.

The collector has 25 to 40% open areadepending on the tower sump size.

The Model 733 is available in any weldablesheet metal, thermoplastic or FRP material.See Section G for material requirements.

For metal construction, the wall wiper iswelded to the column wall. The sump mustalso be field welded into its seat. For somespace-saving designs, field seal welding isrequired at the trough and sump joint.When the sump size exceeds accessdiameter, the sump will be segmented with field-weld construction.

Standard thermoplastic construction isbolted and gasketed. For FRP construc-tion, a seal-weld kit is supplied to seal thejoints.

Optionally, sloped construction for improved drainage and/or liquid movement is available.

■ Corrosion allowance

■ Sloped construction

■ Gasketed and clamped wall wiper

■ Bolt and gasketed construction(when not standard)

■ Gas riser cover as manway (removable from above or below)

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 733

A

B

Hd

Ha

E-3

Page 45: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 833 DECK LIQUID COLLECTOR

The versatile Model 833 is used in towersof all sizes. Tall risers can be provided toallow a large volume of liquid on the deck.Sumps can be added on one side, bothsides or across the center. This collectorhas 25 to 40% open area depending onthe needs of the application.

This collector is available in any weldablesheet metal, thermoplastic or FRP material.For metal construction, the deck andoptional sump(s) rest on tower ledgework;the plate is seal-welded. When gas riserheight exceeds access size, the gas risersare separate pieces which are seal-weldedto the decks.

Standard thermoplastic construction isgasketed and bolted.

■ Corrosion allowance

■ Side sump (one or two)

■ Center sump

■ Tower body flange mounted

■ Bolt and gasket joint construction(specify bolting material)

■ Thermoplastic gas risers with FRPconstruction

CONSTRUCTION DETAILS DESIGN OPTIONS

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

Model 833

A

B

Ha

Hd

E-4

Page 46: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

LIQUID/LIQUID EXTRACTION

Packing is used in counter-currentliquid/liquid contactors with special internals to disperse one of the phases.Selection and arrangement of the internalsdepends on which phase (light or heavy) iscontinuous and which is dispersed. In allcases, feed pipes directing the feed, lightand heavy, are recommended to controlvelocity. It is extremely important to properly feed the dispersed phase to the disperser plate.

In contactors where the light phase (feedwhich enters the bottom of the tower) isdispersed, packed beds are supported bythe Model 834 disperser support plate. Inaddition to supporting the packing, theplates allow proper dispersion or formationof small droplets which rise through thecontinuous phase. In breaking the dispersed liquid into small droplets, the Model 834 provides maximum initialcontact area between the two phases.Because the droplets tend to coalesce inthe packing, beds are typically limited to adepth of 6 to 8 ft [1.5 to 2.5 m]. Multiplebeds, each supported by a Model 834, arerecommended where a total of more than8 ft [2.5 m] of packing is required.

When the heavy phase (feed which entersthe top of the tower) is dispersed, theModel 835 disperser plate is used abovethe top bed. When multiple beds arerequired, the Model 835 is also used tosupport the upper beds and collect andredisperse the heavy phase to the bedsbelow. The bottom bed is supported by aconventional support plate (see Models804 or 818). The Model 835, althoughstructurally different, is hydraulically upside-down compared to the Model 834.In heavy phase dispersed contactors, thesame bed depth recommendations applyas with light-phase dispersement.

It is generally recommended to dispersethe phase with the higher flow rate to generate maximum interfacial contact. The exception to this rule is when the higher volumetric flow rate phase has higher viscosity or preferentially wets thepacking surface.

Surfactants may alter surface properties to the extent that the performance of a liquid/liquid contactor cannot be predicted.

834

835

644

744

DescriptionConstruction

Material Phase

Disperser/support

Disperser/support

Feed pipe

Distributor

Metal

Metal

Metal

Light dispersed

Heavy dispersed

Dispersed (heavy or light)

Continuous (light or heavy)

Metal

ModelNumber

SELECTING LIQUID/LIQUID DEVICES

F-1

Page 47: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 834 DISPERSER/SUPPORT PLATE

The Model 834 disperser/support plateserves two purposes: to support thepacked bed and to disperse the lightphase into the continuous heavy phase.Dump tubes allow the heavy phase to travel downward through the plate. Thelight phase forms a pool under the plateand the orifices generate droplets. Theplate design depends on interfacial surfacetension, viscosity and differential densities.This plate also acts as a re-disperser inmulti-bed towers.

The Model 644 feed pipe is recommendedto feed the dispersed phase to the Model834. Flow rates and turndown may beseverely limited if the Model 644 is not used.

The Model 834 is available in any weldablesheet metal. This plate is supported by afull ledge. All plates up to 32.87 in. [835 mm] ID are clamped to a ledge.Clamps are recommended on larger towers if the load on the plate is less than 100 lbs/ft2 [500 kg/m2]. Maximumallowable loads are 400 lbs/ft2

[2000 kg/m2].

The minimum packing sizes retained bythis plate include #25 IMTP packing, 1 in. [25 mm] Intalox saddles and ³⁄₄ in. [19 mm]rings. Tube restrictor size may varydepending on packing size specified.

■ Corrosion allowance

CONSTRUCTION DETAILS DESIGN OPTIONS

Continuous Phase Flowgpm/ft2 [m3/m2•h]

Max.**

7.5 [18]

* These limits apply to the disperser plate capacity; packing capacity may limit operating capacity.**Turndown of the continuous phase is unlimited.

MaximumDispersed

Turndown Ratio

2.1 [5] 72.3 [175] 5.5:1

Dispersed Phase Flowgpm/ft2 [m3/m2•h]

Min. Max.

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

MODEL 834 FLOW RATE BOUNDARIES WITH MODEL 644*

Model 834

F-2

Page 48: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 835 DISPERSER/SUPPORT PLATE

The Model 835 disperses a heavy phaseinto the continuous light phase. Risertubes allow the light phase to pass upthrough the plate. The heavy phase formsa head on the top of the plate and orificesgenerate droplets. The plate designdepends on interfacial surface tension, viscosity and differential densities.

Feed to the Model 835 of the dispersedphase is recommended with the Model644 feed pipe. Flow rates and turndownmay be severely limited if the Model 644 isnot used.

The Model 835 is available in any weldablesheet metal. The plate is supported by afull ledge.

All plates up to 32.87 in. [835 mm] ID are clamped to the ledge. Clamps are recommended on larger towers if the operating load on the plate is less than 100 lbs/ft2 [500 kg/m2]. Most plates support 400 lbs/ft2 [2000 kg/m2].

The minimum packing sizes retained by this plate include #25 IMTP packing, 1 in. [25 mm] Intalox saddles and ³⁄₄ in. [19 mm]- rings. Tube restrictor size mayvary depending on packing size specified.

■ Corrosion allowance

CONSTRUCTION DETAILS DESIGN OPTIONS

Continuous Phase Flowgpm/ft2 [m3/m2•h]

Max.**

7.5 [18]

* These limits apply to the disperser plate capacity; packing capacity may limit operating capacity.**Turndown of the continuous phase is unlimited.

MaximumDispersed

Turndown Ratio

2.1 [5] 72.3 [175] 5.5:1

Dispersed Phase Flowgpm/ft2 [m3/m2•h]

Min. Max.

Ask your Saint-Gobain NorPro representative about other options at the time of inquiry.

MODEL 835 FLOW RATE BOUNDARIES WITH MODEL 644*

Model 835

A

B

HdHa

F-3

Page 49: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MODEL 644 DISPERSED-PHASE FEED PIPE

The Model 644 feed pipe controls velocityof the dispersed phase flow onto the disperser plate. It is important to preventexcessive turbulence at the phase bound-ary at the plate. The Model 644 controlsfeed velocity and correctly positions thedischarge points to minimize disturbance.If this requirement is not met, this couldlead to maldistribution, loss of dispersion,and premature flooding. For additionalinformation on flow rates, see Models 834 or 835.

The Model 644 is available in any weldablemetal in pipe form and in which flanges areavailable.

■ Bayonet connection

■ Corrosion allowance

■ All flanged construction

CONSTRUCTION DETAILS DESIGN OPTIONS

AModel 644

C

HEADER + 9" [229]

MODEL 744 CONTINUOUS-PHASE DISTRIBUTOR

The Model 744 distributor controls velocity of the continuous phase flow into the tower. Proper control of velocity isimportant to prevent excessive disturbanceof the heavy/light interface, which couldlead to carry-over of the dispersed phase.The maximum continuous phase flowshould be less than 7.5 gpm/ft2

[18.3 m3•m2]. For additional information on flow rates, see Models 834 or 835.

The Model 744 is available in any weldablemetal in pipe form and in which flanges are available.

■ Bayonet connection

■ Corrosion allowance

■ All flanged construction

CONSTRUCTION DETAILS DESIGN OPTIONS

A

C

Model 744

F-4

Page 50: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

TYPICAL TOWER LAYOUT

■ Flash feed arrangement not pictured.

■ Manways at each distributor shouldnot be 180° ± 10° from the inletpipe

■ Allow 36 in. (Hn ) for chimney/collectors

Typical dimensions are offered for rough estimating purposes. Contact Saint-Gobain NorPro to determine more accurate dimensions.

Redistributor

Bed Limiter

Wall Wiper

Support Plate

H.L.L.

Hd

Packed Bed

Gas Feed Pipe (Gas Only)

Redistributor

Bed Limiter

Wall Wiper

Support Plate

Packed Bed

Distributor

Bed Limiter

Support Plate

Packed Bed

Feed Pipe

Hd

6" [150]

6" [150]

BedDepth

12" [300]

6" [150]

6" [150]Di

6" [150]

BedDepth

BedDepth

Di

Hd

6" [150]

12" [300]

18" [450]

Hd

HdHn

18" +Di2

12" +Di2

Distributor

Bed LimiterPacked Bed

Support Plate

Redistributor

Bed LimiterPacked Bed

Support Plate

Bed LimiterPacked Bed

Support Plate

Redistributor

Gas Feed Pipe (Gas Only)

H.L.L.

Face ofInlet FlangeC

Hn Hd

Di

Feed Pipe

Feed Pipe

12" + Di (min.)

20" [500]or

Di x 2Whichever is Greater

Hn + 2" + Manway ID2

Hn

Hd

Hd

8" [200]

BedDepth

Manway + 6" [150]

4" [100]

8" [200]

BedDepth

4" [100]

Manway

2" [50]

BedDepth

8" [200]

Hd

4" [100]

Hn = Dimension from the bottom to the inlet nozzle center-line.

Hd = Height of given model.

For these dimensions, refer to individual item page.

Larger Diameters

(Internals and packing pass through manways for installation)

Smaller Diameters

(Flanged towers)

Rough Dimensions Rough Dimensions

G-1

Page 51: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

GENERAL DETAILS

For the internals described in thisbrochure, Saint-Gobain NorPro provides all removable parts. The internals do notinclude shell attachments for connection orsupport, although these may bequoted/supplied by Saint-Gobain NorProseparately. Examples of attachmentsrequired are:

■ Support rings, sump frames

■ Internal flanges at feed nozzles,including gasket

■ Wall clips for internals support

■ Deflector for Model 755

Exceptions wherein Saint-Gobain NorProsupplies attachments include:

■ Wall wipers for Models 107, 127,137, 1017 and 733

SCOPE OF SUPPLY

Tower IDin. [mm]

up to 18[up to 457]

Plates Resting orClamped to Ledge

in. [mm]

Plates Bolted orWith Leveling Screws

in. [mm]

0.75 [20] 1.5 [40]

18.1 – 24.24[458 – 615]

24.25 – 48.24[616 – 1225]

48.25 – 72.24[1226 – 1835]

72.25 – 96.5[1836 – 2450]

96.6 – 144.5[2451 – 3670]

144.6 – 168.7[3671 – 4285]

168.8 – 216.3[4286 – 5495]

216.4 – 240.5[5496 – 6110]

1.0 [25]

1.5 [40]

2.0 [50]

2.5 [65]

3.0 [75]

3.5 [90]

4.0 [100]

4.5 [115]

1.5 [40]

2.0 [50]

2.0 [50]

2.5 [65]

3.0 [75]

3.5 [90]

4.0 [100]

4.5 [115]

If your ledge size is other than listed above, special consideration must be givento the plate diameter and vessel tolerances.

BAYONET TYPE INLET NOZZLES

MINIMUM LEDGE WIDTHS

Non-lethal service

Meets ASME code for lethal service

Type I

Type II

Type III

TOWER SHELL(EXTERIOR)

TOWER SHELL(EXTERIOR)

TOWER SHELL(EXTERIOR)

G-2

Page 52: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

MATERIALS OF CONSTRUCTION

The following metals are most frequentlyused for tower internals:

■ Carbon Steel

■ Stainless Steel (low carbon contentis preferred) - Ferritic, Austenitic,Duplex, Martensitic

■ Nickel Alloys

■ Copper Alloys

■ Titanium, zirconium

Internals are not stress-relieved orannealed. Internals do not typically classifyto pressure vessel standards.

All fasteners will be ³⁄₈ in. [10 mm] unlessotherwise specified.

All weights shown in this brochure formetal internals are for standard thicknessstainless steel, unless otherwise specified.

Some multiple-piece-construction towerinternals (primarily liquid distributors andliquid collectors) require gasketing for linear joints on the devices. Many choicesof gasketing material are available; braided fiberglass tape and expandedPTFE strip are common. Other tower internals (primarily feed devices and someliquid distributors) require pipe-flange gaskets. Non-asbestos SBR and PTFEsheet are common.

The table below shows rough temperaturelimits for tower internal made of variousthermoplastics. Designs for temperaturesapproaching these limits may need specialheavy construction, especially if the designloads are high or if the tower diameter islarge.

The maximum operating temperature ofthermoplastic internals varies from themaximum temperature of the packing ofthe same material because of the creeptendency of thermoplastics.

Thermoplastic fasteners are generally ¹⁄₂ in. [13 mm].

METAL

GASKETING

THERMOPLASTIC

Fiber Reinforced Plastics are available inthe following materials:

■ Polyester (such as Atlac 382-05A,Hetron 700, Dion 6694)

■ Vinyl ester (such as Derakane 411-45, Atlac 580-05A, Hetron 922, Dion 9100, Corezyn 8300)

■ High temperature vinyl ester (such as Derakane 470-300, Hetron 980)

Reinforcing mat for all resins is corrosionresistant glass. A curing system must bespecified when using polyester, vinyl esteror high temperature vinyl ester resins. Ourstandard curing method is MEKP/Cobalt.Optional methods include BPO/DMA orCHP/Cobalt. The standard surface veilingfor these resins is one-ply nexus; two-plynexus is optional. The veiling is on theinside and outside surfaces of the internal.Cut edges and weld joints are not veiled;they are sealed with a gel coat as standard.

Several types of tower internals requireledge clamps, which cannot be provided inFRP. Specify thermoplastic or metalclamps for these internals.

Atlac, Dion-Cipp are registered trademarks of Reichhold, Inc.

Hetron resin is a registered trademark of AshlandChemical, Inc.

Derakane is a registered trademark of Dow Plastics.

Corezyn is a registered trademark of CommercialResins Div., Interplastic Corp.

FIBER REINFORCED PLASTIC (FRP)

Thermoplastic

Polypropylene

PVC

CPVC

InternalsMax. Operating

Temperature°F [°C]

180 [82]

150 [66]

176 [80]

Other plastics are available.

PVDF 266 [130]

PTFE 392 [200]

G-3

Page 53: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

SPECIAL TOWER INTERNALS

When your specifications for internals falloutside the standards shown in thisbrochure, Saint-Gobain NorPro can modifythe design in accordance with your equipment needs. Saint-Gobain NorProdesigns and fabricates tower internals andpackings in metals, ceramic, graphite orplastics to meet your mass transferrequirements.

Device Model

Distributors 120 Metal internal strainer baskets used to strain internal liquid flow to preventlow flow liquid distributors and Intalox wire gauze packing from fouling.

146 Metal enclosed Intalox distributor used in clean systems with limited height.

176 Metal Intalox trough distributor with parting box and bottom orifices.

854 Metal in-bed distributor to distribute small quantities of liquid feed into a bedwithout separating the random packed section.

Feed Devices 144 Metal suppressed flash vapor distributor which achieves vapor distributionand vapor mixing in a flashing feed or reboiler return.

192 Metal vapor horn for atmospheric and vacuum crude towers.

194 Metal vane-style vapor inlet diffuser.

655 Metal two-phase feed pipe with shelter plates. Used in feeding collectorplates or distributors with parting box(es).

796 Metal gas distributing support plate used in low pressure (low liquid flow)service where vapor distribution in a compact space is required.

Bed Limiters 822 Metal bed-limiter used with Model 1044 spray distributors to reduce spraypattern interference at the top of the bed.

Support Plates 104 Metal non-interfering support plate that allows liquid to pass without diver-sion, eliminating need for redistribution. Limited to short beds of packing.

1004 Metal gas injection type support plate for catalyst beds.

840 Metal gas injection type support plate used to divert liquid to feed a tray or other device or to provide partial liquid draw-off.

Collector Plates 841 Metal in-bed collector/draw off of up to 3 to 5% of column liquid for flows upto 26 gpm [6.0 m3/hr].

Miscellaneous 100 Metal support ledge for field attachment.

101 Metal support beam.

102 Metal support truss.

858 Metal in-bed wall wiper (Rosette type).

111 Metal anti-migration screen to separate different size packing in a single bed.

Also ask your Saint-Gobain NorPro representative about their line of ceramic tower internals. Saint-GobainNorPro provides a complete line of distributors and support plates in a high-strength Aludur® ceramic body.

The following is a partial listing of models which are supplied by Saint-Gobain NorPro, but not specificallycovered in this brochure. For more information on these or other models contact your Saint-Gobain NorProrepresentative.

G-4

Page 54: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

OTHER PRODUCTS FOR REFINING, CHEMICAL AND PETROCHEMICAL PROCESSING

Saint-Gobain NorPro offers a FAST hotline(Fast Action Support Team). No amount ofplanning can prepare you for an emer-gency shutdown. However, when theunexpected happens, the NorPro™ FASTteam stands ready to help you get yourmass transfer tower back in service with-out delay. FAST is available 24-hours aday, seven days a week, to expedite yourorder for replacement tower internals,packings, trays and related parts for plantemergencies or capacity-expandingrevamps.

For FAST service, call your accountmanager or in the U.S. call (330) 813-1000. In the U.K. call 0044 78 74456.

Our Packed Tower Design program helpsyou size your tower and select the properpacking for optimal tower performance.The program calculates pressure drop,efficiency and capacity of NorPro packingsand estimates liquid hold-up.

Saint-Gobain NorPro offers a tray design manual and PC software program to assist engineers in designingand evaluating NorPro™ trays. The pro-gram automates all calculations necessaryfor process design. The software is simpleto use, and it offers easy data file storageand retrieval.

Software is available as a download fea-ture from our web site, www.intalox.com.

From finding out what’s wrong with your tower to providing the necessaryequipment and installing it, a single phonecall covers it all. Saint-Gobain NorPro hasforged a cooperative alliance with threeleading independent service companies,forming a network of specialists dedicatedto meeting all your mass transfer needsseamlessly.

EXPERT INSTALLATION AND INSPECTION

SERVICES BY CANA-TEX FIELD SERVICES

The experts at Cana-Tex Field Serviceswork to put your tower back in servicewithout delay. Installation technicians and engineers coordinate schedules formaximum efficiency and minimal down-time. The firms’ critical path focus assuresyou that your installation activities will becompleted safely and on time. With loca-tions positioned throughout the world, we can guarantee a team of experiencedtechnicians on site when you need them.

INSTALLATION, MODIFICATION AND

REPAIR SERVICES

• Inspection services

• ASME “U” and NBIC “R” codestamps

• CWI and API 510 qualified personnel

• Site supervision and project management services

STATE-OF-THE-ART TROUBLESHOOTING

BY SYNETIX SERVICES

Identifying problem areas quickly andaccurately is the key to getting your towerrunning at peak performance without cost-ly delays. Whether you are troubleshootinga problem tower, establishing a baselinefor future reference or simply looking forways to improve production, Synetix leadsthe industry in tower diagnostics withproven technology and the knowledge toapply it. Synetix has established itself overtheir 30 year history as a world leader withits Tracerco brand of gamma scanningand tower diagnostic services.

• Tracerco™ Gamma Ray Scanning

• Tracerco™ Radiotracer Diagnostics

• Tracerco™ Neutron Backscatter

EXTENSIVE MODULAR PROCESS PLANT

CAPABILITIES WORLDWIDE

The acquisition of Eta Process Plant Ltdexpanded Saint-Gobain NorPro’s capabili-ty to provide completely integrated modular process plants. Our continuum of specialized services begins with conceptual design and continues through site installation, commissioningand training.

Our multi-disciplined engineering teamoffers expertise in the areas of processdesign, mechanical engineering, projectmanagement, electrical engineering,instrumentation and information technology.

We now specialize in distillation, scrubbing and stripping processes for our European customers. Known globallyfor its excellence, Eta’s water deaerationtechnology is available to NorPro customers throughout the world.Customers now can receive the bestmass transfer products available alongwith innovative design services, reliabledelivery, strict quality control and efficientprocess performance.

In the U.S., Saint-Gobain NorPro offerspre-assembled distillation plants throughan agreement with APV AmericasSeparation Technologies division. APV uses the latest process simulationsoftware as well as their in-house pilotfacilities to provide reliable designs fortheir modular process plants. APV constructs each plant in easy-to-assem-ble modules, which contain Saint-GobainNorPro’s industry-leading trays and pack-ings. Their extensive list of successful dis-tillation systems in operation includespharmaceutical, specialty chemicals, beverage, flavorings, fragrances and fuel ethanol processes.

Whatever your process or wherever you are located, Saint-Gobain NorPro has the resources to meet all yourprocess plant needs.

SOFTWARE AVAILABLE

ONE CALL FOR A TRUE EDGE IN

PROBLEM SOLVING

FAST SERVICE

G-5

Page 55: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

NOTES

Page 56: Packed Tower Internals Guide - razifar.comrazifar.com/cariboost_files/Packed_20Tower_20Internals_20Guide.pdf · LIQUID DISTRIBUTORS A-1 Introduction Liquid distributors are used in

Worldwide HeadquartersSaint-Gobain NorPro CorporationP.O. Box 350Akron, OH 44309-0350Telephone: (330) 673-5860U.S. Toll Free: 1-866-NORPRO-1Fax: (330) 677-7245

Main Office EuropeSaint-Gobain NorProEuropean OperationsKing StreetFenton, Stoke-on-TrentST4 2LT EnglandTelephone: (44) 1782 744561Fax: (44) 1782 744330

Main Office JapanSaint-Gobain Norton KKSaint-Gobain NorProSaint-Gobain Building 6F3 Chome 7, KojimachiChiyoda-kuTokyo 102-0083, JapanTelephone: (81) 3 3263 0096Fax: (81) 3 3263 0097

The information herein does not constitute a guarantee or warranty. The Saint-Gobain NorProCorporation warranty is set forth in its standard termsand conditions, which govern sales of Saint-GobainNorPro products. The standard terms are set forth on Saint-Gobain NorPro quotations and acknowl-edgements and are also available on request.

Saint-Gobain NorPro Corporation, worldwide headquarters, sales offices and manufacturing facilities are certified for ISO 9001:1994.

Saint-Gobain NorPro’s European operation is approved and certified through BSI to ISO 9001:1994.

©2001 Saint-Gobain NorPro Corporation 03/01 TIG-2

www.intalox.com

Locations

Saint-Gobain NorPro Corporation

formerly Norton Chemical Process Products Corporation