l energieonderzoek

lllIllll Energieonderzoek• Mediatheek HvU

l •!"«»'™ -^E——< •^ *~*+S * L WA-l>-«-—————————————

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l^S lf Hogeschool

• van Utrecht

iii

BSc product design and engineering final project:

• Design of a hydrogen membrane reactor

lltlill• Energy Efficiency in Industry department

v A-

Benoit VaïsseMarch - July 2004

Energy research Center of the NetherlandsEnergy Efficiency in Industry depiWesterduinweg 3,1755 PETTEN

l Hogeschool van UtrechtFaculty of Science and Engineering

I Department of Industrial TechnologyOudenoord 700,3513 EX UTRECHT

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Abstract:

At the end the result of the methodical design is a cylindrical reactor 2.5m large andabout 6m high, but this dimension is not definitive. It is filled of tubular membranesand heaters. Feed with natural gas and steam, it produces pure hydrogen, usesnitrogen as a sweep gas and gives FkO and CÜ2 as by-products.

Keywords: hydrogen, membrane, reactor.

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In this project the design of a hydrogen selective membrane reactor has been done. ^Such reactor could be employed in 4 important industrial processes in Netherlands land participate in substantial benefits of energy savings and CÜ2 emission reduction.

The main task was to gather the necessary information about hydrogen producing lprocesses, H2 selective membranes, membrane reactors and the overall functioning,then to design the appropriate reactor based on these research. g|

A review of concepts and existing hydrogen membrane reactors is also given, such asanother one on the 4 industrial processes that could use the reactor: ammonia, mmethanol and electricity production, and propane dehydrogenation. •

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Tableof contents:

Abstract: .......................................................................................................................2Table of contents:......................................................................................................... 3Introduction: ................................................................................................................4Chapter 1: General background................................................................................. 61.1 Gas separation and membrane separation technology: .....................................61.2 Definition:...............................................................................................................71.3 The catalysts:........................................................................................................ 101.4 Applications of a hydrogen membrane reactor: ...............................................111.5 Reactors: ...............................................................................................................14Chapter 2: Methodology............................................................................................ 192.1 General design:..................................................................................................... 19Chapter 3: requirements and design results ...........................................................213.1 General requirements:......................................................................................... 213.2 Ammonia process requirements and schemes: .................................................23

3.2.1 Conventional process:...............................................................................243.2.2 New process:..............................................................................................24

»3»<J JT UDvUOflS IclDlC* ••••«•••••••*•••••••••••••••••••••••*••••••••••••••••*••*•••••••••••••**•••••••••••••**••••••••••••• £3

«?«Hr VxOQvtpl &€l€vUOD* •••••••••••••••*•*•••••••••••*•••••••••*•••••••••••»•••••••••••*•••••••••••••••••••••••••••••*•• /

3.5 Dimensioning of the cylindrical vessel:..............................................................283.5.1 Number of membranes tubes:.................................................................. 283.5.2 Catalyst volume evaluation:.....................................................................283.5.3 FDC heater tubes determination:............................................................29

j«o .KtCcicior moociinfi* ••••••••*••••••••••••••••••••••*•••••*•*•••••••••••**••••••••••••*•••••••••••*•••••••••••••*•••• «3 j.3.6.1 Tubes installation in the reactor:.............................................................313.6.2 Disposition summary:...............................................................................383.6.3 Vessel dimensions:....................................................................................393.6.4 Reactor schemes:.......................................................................................40

Chapter 4: Conclusions and discussion: ..................................................................42Acknowledgment: ......................................................................................................43APPENDIX:............................................................................................................ 44Reference: ...................................................................................................................77

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Introduction: ^

The Energy research Centre of the Netherlands is the largest research centre inthe Netherlands on the field of energy. At this moment about 900 people work at ^ECN, which is situated in the dunes near Petten, a village in the northern part of •Holland, about 40 km up north from Amsterdam.

The research centre carries out research on the field of energy. With this work the •researchers move between fundamental research on universities and appliance ofknowledge and technologies in practice. •

The energy research at ECN is focused on a three-step approach to solve the problemswhich arise with the use of energy like environmental pollution and climate change •and which have already assumed serious proportions. This three-step approach to |meeting our energy requirements has been called the trias energetica

First, the energy demand must reduced, by using energy as efficiently as possible.Next, more sustainable energy sources such as solar, wind, and biomass must be used.And fïnally, we must use fossil fuels - for as long as they are indispensable - in thecleanest possible way.

1. Reduce defnsnd(energy saving)

Energy Demand

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2. Maximteetheuseof ^ ^ ^renewabte energy ^ ^ ^ k 3. Use fces» fuete In the •sources ^ ^ ^ L. cleanest possible way J|

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Energy Efficiency in Industry (EEI), one of the research units of ECN, concerns itself ™with the first component of the trias energetica: efficiënt use of energy, leading toenergy savings, particularly in energy-intensive production processes. By focused •knowledge- and technology-developments, EEI contributes to innovative solutions for ~the reduction of energy use and raw-materials use in industry. ^

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One of the research areas of the EEI department of the ECN is separationtechnology. By using membrane separation processes, the energy efficiency of energyconsuming industries (chemical, oil) can be increased. One application is the use ofhydrogen selective membranes for energy efficiënt hydrogen and electricityproduction. According to EEI researchers, the total energy saving potential of usinginorganic hydrogen selective membranes in the Netherlands is about 15 PJ/year,which is equivalent to 840 kton/y CÜ2 emission reduction. For this application, aninorganic hydrogen selective membrane reactor is needed with optimal dimension tooperate in large-scale production, which could be used in 4 processes involvinghydrogen separation:

• Ammonia production via steam reforming and water gas shift• Electricity production with COa caption via steam reforming or water gas

shift• Propane to propylene dehydrogenation• Methanol production

In these processes, hydrogen has a limiting effect on the reactions and shouldbe removed, traditionally downstream of the reactor, which lower the once-throughconversion in some cases. The use of a hydrogen selective membrane reactor for theremoval of Hb in the reaction section could lower the hydrogen partial pressure in thereactor and shift the reaction equilibrium. This would result in an increase in the once-through conversion, leading to the energy savings mentioned above.

The objective of this project is the design of the optimal "basic unit size"(BUS) of a hydrogen membrane reactor, that would be used in the above mentionedprocesses. The basic engineering of the BUS reactor would lead to a definition of thebasic geometry and size of the membrane component and therefore a guide for themembrane development.

In chapter l is given some necessary background about the membranes, thehydrogen membrane reactors and the processes in which they can be used. Then inchapter 2 I describe the design method I used in this project. Chapter 3 gives theresults of the literature study, the requirements for the hydrogen membrane reactor,results of the design method, the calculations and the final design. Finally, someconclusions are drawn in chapter 4.

Approach:

Produces high, quality productsGreater flexibility in designing systems

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I handled this project with in mind to get insight the subject by a literature ^study, through books, patents, publications and internet research. I focused my —researches on the hydrogen separation processes and the chemical reactions involved; •also the membranes, their sorts and their characteristics; then the membranes reactorsalready existing, some concepts too, and their overall functioning. I tried that way to «find out the most appropriate information to start and work from. •

Chapter 1: General background •

1.1 Gas separation and membrane separation technology: m

The membrane gas separation technology is over ten years old and is proving to beone of the most significant unit operations. These processes compete with technology •alternatives such as adsorption, cryogenic distillation etc. in niche application areas. |The membrane processes enjoy certain advantages, compactness and light in weight,low labor intensity, modular design permitting easy expansion or operation at partial Acapacity, low maintenance (no moving parts), low energy requirements and low cost |especially so for small sizes. Membranes made of polymers and copolymers in theforms of flat film or hollow fiber have been used for gas separation. •

A membrane separation process enjoys numerous industrial applications with thefollowing advantages: fl

• Appreciable energy savings ™• Environmentally being ^• Clean technology with operational ease J• Replaces the conventional processes like filtration, distillation, ion-exchange

and chemical treatment systems fl™

lThe membrane gas separation has been used for hydrogen separation and recovery, Aammonia purge gas, refinery hydrogen recovery; 'syngas' separation in petrochemicals |industry, CÜ2 enhanced oil recovery, natural gas processing, landfill gas upgrading,air separation, nitrogen production, air dehydration, helium recovery etc. It may enjoy •the following applications in the near future: Na enrichment of air Low level, Oa |enrichment of air, HI and acid gas separation from hydrocarbons, Helium recoveryand natural gas dehydration. B

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1.2 Defmition:

A simplified working definition of a membrane can be conveniently stated as a semi-permeable active or passive barrier which, under a certain driving force, permitspreferential passage of one or more selected species or components (molecules,particles or polymers) of a gaseous and/or liquid mixture or solution.

The driving force can exist in the form of pressure, concentration, or voltagedifference across the membrane. Depending on the driving force and the physicalsizes of the separated species, membrane processes are classified accordingly:microfiltration (MF), ultrafiltration (UF), reverse osmosis (RO), dialysis,electrodialysis(ED) and gas separation, the one dedicated to hydrogen separation. Thedriving force in that case is the partial pressure difference (total pressure *concentration) detailed below.

A membrane separation system separates an influent stream (feed) into two effluentstreams known as the permeate and the retentate. The permeate is the portion of thefluid that has passed through the semi-permeable membrane, whereas the retentatestream contains the constituents that have been rejected by the membrane.

feed retentate

Separatedeffluent

Membrane separation layer

permeate Sweep gas(counter-current)

Different gases pass through certain membranes at significantly different rates, thuspermitting a partial separation. The rate of permeation is proportional to the pressuredifferential across the membrane and inversely proportional to the membranethickness. The rate of permeation is also proportional to the solubility of the gas in themembrane and also to the diffusivity of gas through the membrane.

Two important characteristics of membranes are their permeability and selectivity:The permeability, or permeation rate, is the volume flowing through the membraneper unit of time and area.

The selectivity, or separation factor a is the selectivity of a membrane towards amixture component.

Gas separation is thus affected by three key performance attributes of membranes:selectivity towards the gases separated, membrane flux or permeability and the life ofthe membrane, maintenance and replacement costs.

Nowadays available membranes can match with the selectivity demand in ammonia &methanol production, but an increase in permeability and a decrease in price arenecessary for an economie viability.Other important points are their stability towards chemical environment, hightemperature and pressure conditions.

For the production of high purity hydrogen, both organic (polymer) and inorganicmembranes can be used. Inorganic membranes have great potential in gas separationespecially at high temperatures. It relies on the inherent thermal and chemicalstabilities of many inorganic membranes and the possibilities to design the desiredpore size and pore surfaces. A number of potentially important gas separationapplications using inorganic membranes are surveyed. These are some hydrogenseparation applications: hydrogen/hydrocarbons, hydrogen/carbon monoxide,hydrogen/nitrogen, hydrogen/carbon dioxide, hydrogen/coal gasification product.

Dense inorganic membranes such as palladium-based or zirconia membranes provideextremely high purity gases, but their permeabilities are usually low, thus making theprocess economics unfavorable. So far ECN focuses on the development of inorganicmembranes, dense or porous, metallic or ceramic based, mostly tubular and with athin layer of Pd-based alloy on its external side (outside^inside fïltration).

Palladium alloy membraneCeramic porous substrate

Basefayer l Intemwdiate fK Top layer of l *t- Pailadium alloylayer Top layer substrate membrane

Figure l - palladiurn alloy based membrane

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Figure 2 - overview of tubes and cross section of fractured sample of Pd/23%Ag membrane layeron ceramic support

Through the dense palladium alloy membrane, the transport mechanism is thesolution-diffusion type.

Hydrogen dissolved in a metal hybrid system is considered to behave in atomic orionic form which is more reactive than molecular hydrogen in gas phase. Thepermeation of hydrogen through metals (such as palladium) entails three processes:

(1) dissociative chemisorption of hydrogen on the membrane surface followed bydissolution of the atomic hydrogen in the strucutural lattice of the metal

(2) diffusion of the dissolved hydrogen in the membrane.(3) Desorption of combined hydrogen atoms as molecules.

The driving force for the diffusion across the dense palladium membrane is theconcentration difference of the dissolved hydrogen in the atomic form. The rate-limiting step is often the bulk diffusion as in the case of palladium membranes.

Figure 3 - Transport mechanism of hydrogen through palladium membrane

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1.3 The catalysts: —

A certain amount of catalyst will be necessary in the reactor, next to the ^membrane and the components involved in the process, to favor the reaction. Here is a •short description of the catalysis principle.

Catalysis is the acceleration of a chemical reaction by a small quantity of lsubstance, the catalyst, the amount and nature of which remain essentially unchangedduring the reaction. A catalyst can only accelerate a thermodynamically feasible mreaction. It cannot change the position of the equilibrium in the case of a reversible |reaction because the catalytic action accelerates the forward and the reverse reactionsto the same extent. On the other hand, a given catalyst will not necessarily catalyze mequally all or several of the possible reactions in a reaction mixture. By the judicious |choice of catalyst, catalysis can be used to accelerate selectively the desired reaction.

This selective and directive action of catalysis, as well as the acceleration of |reactions, is responsible for the widespread use of catalysts in industrial chemistry.

In heterogeneous catalysis, the catalyst phase is separate from the reactant 0phase, and catalyst is usually a solid, whereas the reactants are gases or liquids.Examples of heterogeneous catalysts are platuiuniT-rhodium wire gauze used for the ttoxidation of ammonia to nitric oxide; nickel on kieselguhr for hydrogenation of edible |oils; and amorphous and crystalline aluminosilicates for cracking of high molecularmass petroleum fractions. Because in heterogeneous catalysis the reaction occurs by ttcontact with the catalyst, sometimes this type of catalysis is called contact catalysis •and the catalyst is referred to as a contact catalyst.

ffCurrently processes and methods based on both heterogeneous and •

homogeneous catalysis are integral and important techniques of modern industrialchemistry. In the petroleum and petrochemical industry, catalysis is used in almost levery purification, reflning, or reaction step. In the production of synthetic gaseous •and liquid fuels from coal, tar sand, and oil shale, catalysis is important.Approximately 70 % of the leading large-tonnage chemicals are manufactured with •help of catalysis, including ammonia, methanol and propylene. ™

Heterogeneous catalytic reactions can be described as consisting of the •following steps: (1) adsorption of at least one of the reactants on the surface of the *catalyst; (2) reaction of the adsorbed species with the catalyst to yield an intermediatecompound; (3) reaction of the intermediate with another adsorbed or nonadsorbed Breactant, resulting in the product; and finally, (4) desorption of the product. Incomplex reactions two or more intermediate compounds may participate, and the final —reaction product may form in a reaction sequence involving several steps. •

Because heterogeneous catalysis occurs only on the external and internal surfaces ^of the catalyst, the rate of reaction may be influenced by heat and mass transfer, to land from the catalyst partiële, and by diffusion in and out of the catalyst pores.

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1.4 Applications of a hydrogen membrane reactor:

In the four processes mentioned in the introduction, propane dehydrogenation,ammonia, methanol and electricity production, the application of a hydrogenmembrane reactor instead of the conventional process leads to benefits in terms ofenergy efficiency and emission reduction, and the use of this technology turns theseprocesses to be cost-effective (see table 1).

Process

Dehydrogenationof propane to

propylene

Electricityproduction

Ammoniaproduction

Methanolproduction

Savings dueto

Shift ofreaction

equilibriumShift ofreaction

equilibrium inwater gas shift

reactorShift ofreaction

equilibrium insteam

reformerShift ofreaction

equilibrium insteam

reformer

Energysavings

2.4 PJ/y foracommercialsize plant

13.7 - 15.95PJ/y for plants

in theNetherlands

0.88 PJ/y forplants in theNetherlands

CÜ2 emissionreduction

47 kton/y for acommercialsize plant

1640 kton/ycompared to aconventional

coal fired plant

767 - 893kton/y for

plants in theNetherlands

49 kton/y forplants in theNetherlands

Remarks

No process inthe

Netherlands

No plant in theNetherlands

Table l - energy savings and CO2 emission reduction

In order to define the requirements of our product, I summarized in a table therelevant data about the working conditions inherent to each process. I focused on thetemperature range, the pressure range, the components and reactions involved, and themembrane area needed to reach an economically viable production. I tried to fix ifpossible if one process particularly is more "intensive" and could serve as a basis ofthe design.

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Ammonia production Methanol production propylenedehydrogenation

Electricityproduction

Description and/or aim of separation

H2removal in steam reformer=> higher efficiency + lower

energy useH2removal during the reaction

=> shifting reaction equilibrium____=> higher yield____

H2removal in steam reformer=> higher efficiency + lower

energy useH2removal during the reaction

=> shifting reaction equilibrium____=> higher yield_____

H2removal during thereaction => shifting

reaction equilibrium =>higher yield

H2removal during thereaction => shifting

reaction equilibrium =>higher yield + CO2

reduction

Feed desulphurized natural gas(86.1% C1^ +steam

desulphurized natural gas(85% C H4) + steam Propane rid of C4

Syngas from coalgasifier

CH, + Hp •* CO + H2 + X/2K,

CO + H-O •» CO, + H, CO + H-O •» CO2 + H- CO + H-O •* CO, + H,

Pressures (bar) Combinedwith SR in

MR(4)

Combinedwith SR in

MR (4)

500-600(800-1000)

500-600(800-1000)

Temperatures Combinedwith SR in

MR(250-500)

Combinedwith SR in

MR(250-500)

475*2.5(3 modules),or 312*2.5(l module)

Membranearea needed(m2)

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As can be seen, ammonia and methanol production are very similar processes in allfields, except that the ammonia production pressure range is a bit higher. Electricityproduction and propane dehydrogenation show a lower pressure range and are onlybased on the water gas shift reaction.

The membrane areas needed are estimations of the necessary amounts to reach theeconomie and COa emission savings for each process. It will also be a determinantpoint to dimension the module later, despite it is obvious that the whole necessarymembrane area for a process could not fit a reactor of reasonable size, and thus, thatthese areas would be matched by a serial of BUS reactors.

I decided to base the design on the ammonia production process due its similarity withthe methanol production process and its more severe conditions than those ofdehydrogenation and electricity production. Besides, it also represents in Netherlandsthe most common process (2500 kt/y) and the highest energy savings (see energysavings previous table).

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1.5 Reactors:

Drawings and sketches of these concepts can be found in appendix 1.

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The idea of using hydrogen selective membrane in a reactor is not new and severalconcepts can be found in patents, literature or dedicated web sites. They are obviously _not all elaborated for the same processes, or for the same working conditions and •production objective, but all surveyed concepts in the following table show relevantcharacteristics of tubular hydrogen selective membrane reactors and I tried to outtake Mbenefits and disadvantages of those concepts: l

The ease of set up, replacement and removal of membranes or catalyst; «The evacuation of permeate, via a vacuüm pump or a sweep gas, which involves more |or less recompression downstream of the reactor;The heat management, how heat is provided and homogenously distributed among the •reactor; |The turbulences, related to the mixing of the feed and its distribution in contact withthe membrane surface. •The evaluation of this benefit must be nuanced due to the little information sometimes |given about those concepts.

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raferance(espacenet)

1

EP1411029

2

3

W02004022480

4

WO2004022480

reactor ^^m«nbrane^^^J|HB| turbutonces

simplecylinder

simplecylinder

severaltubularcatalystbedsinacylindrical

shell

sameprinclple, inone shell

oneorseveraltubularporousceramfc

One Pd-Agmembrane

several tubes

One tube

reactorcoaxial

reactorcoaxial

concentric& coaxial

totheshell

concentric& coaxial

totheshell

outersideto

innerside

outersideto

innerside

outersideto

innerside

outersideto

innerside

no parttcularpath

no particularpath

feedftowsafonganannulus

aroundthemembranes

no particularpath

inputs

oneentry,

probablypre-

mixedIV7OU

entry,probably

pre-mixedfaad

oneentry,pre-

mixedfeed

oneentry,

probablypre-

mixedfeed

avacuation

vacuümpump

vacuümpump

vacuüm,optionnalysweepgas

vacuüm,optionnalysweepgas(cocurrent)

catalyst

thin layeron thetube

packed-bed

pellets

packed-bed

pellets

packed-bed

pellets, +inert

pellets onthe top

hoater

pre-heatedgas + ?

reactorenclosed ina fumace

FDC tubesin the

catalystbed,

concentricto

membranes

FDC tubesinan

annularspace

around theixiiafyoi

bed

advantages

can use existingmodule designssimple module

design

temperaturecontrol, easy

removal of pelletsand membrane,

fine tuning catalystand membrane

possible

heat management(FDC tubes),

mixing?

sweep/vacuum,heat managnt,

removal of partsand components,turbulence feed

due to catalyst bed

dlsadvantagea

low permeate pressure,low membrane area, extraN2 in retentate. complex

design, number ofconnections, possibility

damaging membrane dueto catalyst particles

low permeate pressureand yield, Fumace

heating, no multitubesdesign available, possible

problem with mountingdue thermo-wells.

possibility damagingmembrane due to catalyst

particlespossibly low permeate

pressure, elementsremoval, diffusionresistance feed to

catalyst, complex design,possibility damaging

membrane due to catalystparticles

possibility damagingmembrane due to catalystparticles, low membrane

area

Table 2 - reactor summary - part l

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roferonco(espacenet)

5

WO2004022480

6

EP0962442A1

7

US2003171442

8

JP2003277009

reactor ^nwn*J2JJ^^^^^^^B~~*"'i>ulence8

large-scalecylindricreactor

O2depletioncylindricreactor

cylinder

cylinder,apparentlylarge scale

severaltubes

severaltubes

severaltubes

severaltubes

concentric&coaxialto

the shelf

reactorcoaxial

reactorcoaxial, in 2concentric& coaxial to

the shell

reactorcoaxial

outersideto

innerside

outersideto

innerside

undefined

outersideto

innerside

upanddown-ward feed flow

atongthemembranes

use of plates toguide and mix

the feed

no particularpath

Inputs

oneentry,pre-

mixedfaaH

2 entries,CH4andsteammixedinside

2 entriesfeed

mixed atthe

entranceof theshellone

entry,probabty

pre-mixedfeed

evacuatlon

vacuüm,optionallysweepgas

sweep gas,countercurrent

vacuüm

sweepgas,co-current (2),and counter-current (3)

catalyst

packedbed

containingFDCandmembrane tubes

unknown,contained

in aclosedcentral

part of theshell

packed-bedinthereaction

part of theshell

liquid-pnase

catalyst

neater

pre-heatedgas and FDC

tubes

2 steam inputson top &

bottom, and athermal

isolation (tomaintain T and

protectextern?)

feed mixed &pre-heated at

the entrance ofthe shell

no info

advantages

sweep, turbulencefeed due to catalyst

bed, heatmanagement (FDCtubes), solution for

differences inthermal expanston,

related to ECNpatent and SMS

module, removal ofpartsand

componentsThermal isolation,filling/removal ofcatalyst, steamheating? feed

transport & mixing,turbulence feed due

to catalyst bed,removal of parts and

components?

turbulence feed dueto catalyst bed,bumer heating,

sealing by weiding?

same ad anddisadvantages as 3,4 and 5 except for

heating

disadvantages

complex design,number of

connecttons, possibilitydamaging membrane

due to catalystpartteles

complex design,number of

connections, possibilitydamaging membrane

due to catalystpartteles

low permeate pressure(vacuüm), extra N2 in

retentate

no word about heatingor isolation, liquid

catalyst in our casecatalyst particles

Table 3 - reactor summary part 2

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reference(espacenet)

9

tokyo gasreactor

10

11

reactor l Membranes I BBBHLl turbulencesiBBBBBBBB i il

cylinder

cylindricshell

cylindricshell

severalplate ortubular

membranes

4to10tubes

2PdAghelicoidal

tubes

reactorcoaxial, in

aconcentric

circlearound afumace

reactorcoaxial

rniloH

together,reactorcoaxial

outersideto

innerside

outersideto

innerside

innersideto

outersideseparation

no particularpath

nothing

inputs

oneentry,pre-

mixedfeed

oneentry,

probablypre-

mixedfeed

evacuation

vacuüm

vacuüm

centercollection

tube

catalyst

packed-bedin betweenor around

themembranes

ground,sieved

catalyst

notmentioned,probablythin layer

on theinside partof the tube

heater

burner inthe center

of theshell

heatingtape on

outer side,or furnace

advantages

heating system;turbulence feed due to

catalyst bed; solution fordifferences in thermalexpansion, removal of

parts and components?

no turbulences, amountof tubes

lack of i

can be settled up withtubular membranes

disadvantages

low permeate pressure, fewmembranes, extra N2 in

retentate? complex design,number of connections,

possibility damagingmembrane due to catalyst

particles

removal, liquid catalyst

nformation

few space dedicated tomembranes, furnace energy

consumption

Table 4 - reactor summary - part 3

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Chapter 2: Methodology

2.1 General design:

The methodology used for the design is based on Kesselring method, which consists ingenerale several concepts via a function table, then assess those concepts and make choicethanks to a parametric graph.

Functions

Function l Fl casel Fl case 2 Fl case 3

Function 2 F2 case l F2 case 2

FunctionS F3 case l F3case2 F3case3 F3case4

Table 5 - example functions table

The functions listed in the homonym table comes directly from the previous literature studyand general requirements of the reactor (e.g. feed distribution, heat distribution, etc..), and foreach one are several solutions, thus permitting different concepts by different associations.This table is determinant in the up coming morphology of the reactor.The resulting concepts are then assessed in two tables, dedicated to the use and fabricationaspects.Theses tables contain different criteria with their own weight factor, and are presented asfollow:

Aspect

Criteria 1

Criteria 2

Criteria 3

Sum

Relative sum

Concept A

2

3

1

13

0.54

Concept B

4

3

1

15

0.62

Concept C

2

3

3

17

0.7

Ideal

4

4

4

24

1

Weight factor

1

3

2

Finally, Kesselring method leads us to report on a graph the results of assessment tables,showing for each concept its adequacy to both aspects thanks to an ideal line.

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Ideal line

• B

O

O lst aspect l

Kesselring graph

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ll• Chapter 3: requirements and design results

3.1 General requirements:

™ Those are some general considerations I gathered at the beginning of the design, based onPugh's product design specifications.

m The module:

The module has the particularity to make happen reactions and H2 separation in itself.• Before working on a concept generation and on the dimensioning of this concept, we gather in• the following section some ideas about general requirements of such a reactor, inspired by

conventional methods of design.

l Performance:

Life in service:

Several years of full performance, independently of membranes performance.

• How much Ha/per BUS: to be determined by relating f eed flow, permeability, membrane area,H2 recovery, temperature, pressure difference, sweep gas/output flow.

I ldeal membrane surface per module: 400 to 500 m2 (depending on related moduledimensions)how fast: input flow, conversion rate, output flow

I range of temperaturerange of pressure

0 Environment:

• Can fit a chemical/electricity plant, outside or inside, clean area

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lMaintenance:

9 Ease of access to parts that are fundamental or likely to require maintenance (e. g. membranes,sealings, heaters, plugs...)

Manufacturing facility:

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Reactor expected to fill existing plants, without being designed for one in particular, but witha "universal" adaptation ability, via the Basic Unit Size concept..

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However, a view/idea of the typical place where the reactor will be installed could be useful, Bfor an estimation of reasonable size for instance.

Size: ™

Related to the performance via the yield per module expected, and thus the membrane area Bneeded. Related also to the space provided, but we can assume that the concerned plants canprovide enough space, since the membrane reactor is sometimes replacing several modules .(e.g. reformers). Related then to the shipping, via the ability (physical or legal) or not to be •transported via road, water, air..

Weight:

Allied to size and to material chosen, should not prevent the module from being moved or lhandled during manufacture, transit or installation.

lMaterials:

reached, especially conceming sealing and element-to-module connections, exposed tothermal shocks and expansion. •

Standards and specifications: •

Is the module designed to dutch or international standards? Is there is Standard in membranereactor module? l

Safety: •

The safety aspect of the proposed design must be considered, especially when hazardouschemicals, high temp & pressures are involved. There are probably standards or legislation •relevant to the implementation of machines in chemical plant. *

Besides, we have to keep in mind and minimize anything that could represent a risk for the •user, like shapes (sharp corners, moving parts where closing, drapes or parts of the body are ™likely to be snagged) or even lack of knowledge/documentation for the user.

Installation: —

Module must interface with other products, or be assembled in the chain of production, soinstallation must be considered in the design. Maybe in surveying the parts likely to be up and ^downstream to the reactor, in the different processes. •

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3.2 Ammonia process requirements and schemes:

Based on the literature study and some inquiries after the personnel involved, I obtained thefollowing results concerning the ammonia process conditions, and thus concerning thepressure and temperature range that the reactor must support.

Feed: 1500 kmol/hr (=28 ton/hr) natural gas40-51 bar

Product: >6872 kmol/hr (=60 ton/hr) synthesis gas with H2/N2 ratio = 3no CO and CO2max. 0.8 % CHU and 0.1 % H2O

Reactions: Steam reforming CH» + H2O --> 3H2 + COWater gas shift CO + H2O -> H2 + CO2

Membrane area: 6000 m2

Operating conditions at the reactor side:T = 500 °CP = 35-50 bar higher P => higher driving force and therefore preferableFeed flow =115 ton/hr (= 1500 kmol/hr natural gas and +/- 4851 kmol/hr water)

Feed composition: natural gas (with 86% CHOand water (steam/carbon ratio = 2.5-3)

Operating conditions at the permeate side:T = +/- 500 °C assumed the same as the reactor temperatureP = +/-1-6 bar the maximum P could be higher; this depends on the maximum P_H2 at

the reactor side. In the end the P should be chosen by optimisation: lowP => less membrane surface area, but high energy requirement forcompression of the product gas.

Feed flow (sweep gas) = +/-2000 kmol/hr N2depends on the amount of H2 permeated and the H2/N2 ratio

hi the ideal case (100% conversion and 100% H2 yield) required:• 3186 kmol/hr water• 2065 kmol/hr N2

Other gasses for sweeping are also possible. However this would require additionalseparation/purification step(s).

Next are schematic representations for the ammonia production of the old process first, and ofthe new process using membrane reactor then, showing how it becomes greatly simpler.

23

3.2.1 Conventional process:

Natural gasl 43 bar

s

F

Desulphurisatic

tnam — _

480 °C

-i ifl nflT

140 b a r — ir^Syngas

(H? + N,)

>n

AirReformer 1 Refo

1 + > i800 °C 98Ct

nntti 30 bar Methanati••mP l 275 °C

H2O

rmer i —————— i> ^ HT Shift——— > —°C 350 °C

on 4 c°2 removal

50°C

CO2

LT Shift

200

'iH2O

°C

3.2.2 New process:

Natural gas

+ Desulphurisation

Steam

:L

l

Membrane Reactor CO2+ H2O

- N2

Syngas(H2 + N2)

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3.3 Functions table:

The function table proposes several solutions to necessary functions of the reactor. Thesefunctions are detailed below, the table can be found in appendix 3.

External shape:This describes the general form of the vessel and its inner containment.

Membrane disposition:The different patterns of disposition influence the homogeneity of the heat transfer and thenumber of membranes fitting in the reactor.

Heat input:The different solutions come from the literature studied. "FDC tubes" means flamelessdistribution combustion, and the concept is detailed in appendix 3. It happens to be tubesdisposed among and parallel to the membranes, spreading heat around them.

Membrane diffusion direction:Depends of where on the inside or outside part of the tube is the membrane separation layer.ECN membranes are usually of the outside to inside separation type.

Flow feed/ sweep gas:This function details if the permeate will be evacuated by a sweep gas, in the same directionor not that the feed flow, or evacuated by a vacuüm pump. This last solution has thedisadvantage to give hydrogen at a very low pressure. The use of a sweep gas minimizes thisproblem and the direction given to it permits to compensate the hydrogen partial pressure andincrease the permeation of hydrogen through the membrane.

Catalyst:For these three solutions, the use of small pellets has the additive benefit of being a turbulencemedium combined with the use of a fast feed flow.A thin layer of catalyst deposited on the surface of the membrane is a more expensivesolution.

Turbulence medium:The turbulence medium makes the feed invest the whole vessel and ensure a maximumcontact with the membranes surfaces. As said before, speed combined with pellets of catalystturn to be a turbulence medium.

Feed flow over the membrane:Details the possible flows on membrane surface if some particular distribution pattern is set.

Entrance feed:Details possible ways of feeding the reactor

25

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H2 outlet: _Details possible ways of evacuate the permeate •

Sealings: —Sealings choice determine how the membrane tubes are connected to the vessel and what •material will make the support of the membrane layer, in regards to problems and benefitslike strength or thermal expansion. _

Manifold distribution:For the last two functions, the solution given tells if the reactor will contain the tubes and their Mconnections (feed, sweep,..). one of them, or just the tubes. l

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3.4 Concept selection:

After generating 4 concepts via the function table, 3 persons including myself separately filledthe assessment tables, then compared and discussed our choices, and eventually choose one tobe developed, concept A, the closest to the ideal line between use and fabrication aspects.

concepts visualisation

0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9

Figure 4 - Kesselring representation

The concept A features some parts like FDC tubes (see appendix 3) and membranes onstainless steel support sealed on two sides, which are new and will necessitate furtherresearches. lts characteristics are:

A cylindrical vessel, containing membranes on porous metallic support tubes fixed on bothsides and disposed on triangular pattern. There are one entry for the feed and one generaloutlet for the permeate. The separation is made from the outside to the inside part of the tubes.The heat is provided by FDC tubes. A sweep gas for the evacuation is used, in counter currentto the feed flow. The feed is mixed before entering the reactor, where its flow and the pelletpacked bed catalyst ensure the turbulences. The distribution of the sweep to the tubes and thecollection of permeate from the tubes happen inside the reactor.

Function table, assessment tables and explanation of the criteria can be found in appendix 3.

27

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3.5 Dimensioning of the cylindrical vessel: l

After choosing a concept, I dimensioned the vessel starting from the membrane area of the —order of 500 m2 per BUS reactor. The main points to be taken into accounts for this are as lfollow: *

• Membrane area per module |• FDC tubes area corresponding, depending on the necessary heat duty to maintain the

desired temperature. •• Amount of necessary catalyst to achieve the reaction. *• Types, dimensions and price of membranes and catalysts available. H

Inquiries about membranes and catalysts can be found in appendix 4.

For the whole process, the heat duty provided to the reactor is 64 MW. •

The point is to determinate an amount of tubes to reach the membrane separation area of 500 •m2 per module in a reasonable size vessel, keeping a space for the heating tubes and the |catalyst which respective amount and sizes will be also determinate.

3.5.1 Number of membranes tubes: |

In appendix 5 can be found all the evaluations of the number of tubes in a BUS reactor •varying three parameters: 8The membrane area per BUS reactor (400 to 450 m2), and the lengths and diameters of thetubes. •For a 500 m2 membrane area, 3183 membranes with a length of 2.5m and a diameter of 20mm •are necessary.

3.5.2 Catalyst volume evaluation: •

Estimation for NHa production: l

For a 500 m2 area:

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Assuming that most of the separation is done via steam reforming, we take a 3 kg/m2 catalyst,in pellets of 2 to 9 mm diameter and 1100 kg/m3 volumic mass.

Needed mass: 500*3 = 1500kg catalystAs a volume: 1500/1100 = 1.36 m3 catalystThe space necessary to fill this amount of catalyst may overtake a volume of l .36 m3, due to •the arrangement of pellets. Thus we should consider adopting the smallest possible size ofpellets to gain space in the reactor. _

See appendix 4.

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3.5.3 FDC heater tubes determination:

We determine in this part the necessary area of heaters for a given surface of membranes(6000 m2 divided in 12 modules). The extracts from the patents where FDC tubes functioningis described give a range of heater area necessary for a membrane area, but also an examplewhich is out of this range, so we decide to determine our amount of FDC tubes area using thisformula:

Q = U*A*deltaT

Result of a calculation sheet of JW Dijkstra, researcher at ECN, and where:U: heat transfer coëfficiëntQ: heat duties in the membrane reactor for a feed flow of 1500 kmol/hr and aconversion of 95% CHU.Delta T: temperature between FDC tube inner side and catalyst bed.

Q = 64.3 MW (for 6000 m2 membrane area)U = 250 W/m2.KFor a AT of 300°K (500°C in the reaction part, 800°C in the FDC tube)

FDC tube area = 72 m2

Then we determine an amount of heater tubes that can fit in a cylindrical vessel with themembranes in an appropriate pattern.Number of FDC tubes:353 tubes diameter 26mm, minimally 2.5m long.Tables and results for different parameters can be found in appendix 5.

An appropriate material used for the FDC tubes would be SA-312 stainless steel, suitable forthe conditions: external pressure of 40 bars and temperature of 500°C (out) and 800°C (insideauto-ignition temperature, see appendix 2: FDC tubes).

The ideal thickness of such a tube is dimensioned at 2mm.Overall determination can be found in appendix 6: Material choice and reactor partsdimensioning.

Next is a representation of a open-end FDC tube. The inner blue tube carries the heating fuel,and distributes it via small nozzles to the mixing chamber previously filled of heated air. Theoverall functioning of FDC tubes is detailed in appendix 2: FDC tubes.

29

Nozzles

Mixing chamber

Open end

Figure 5 - FDC tube open view

30


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3.6 Reactor modeling:

Drawn with CoCreate OneSpace Designer

3.6.1 Tubes installation in the reactor:

According to the results we have so far about the membranes area needed, for the overallprocess and per module, we try to make an arrangement of the necessary amount ofmembranes, heater tubes and catalyst in one module.We choose in the function table a triangular pattern that I am eventually affecting to theheaters, each one will be surrounded by 8 membranes. It firstly changes the ratio ofmembrane/FDC tube number and thus the areas ratio, but the final disposition compensates it.Another case (case 1) was explored to compare.

Case 1: one membrane enveloping each heater

This case is not feasible because with any heater diameter, according to the ratio of areas, theresulting membrane diameter is much larger than the maximal distance between membraneand heater (2.54 cm, according to the patent, see appendix 2: FDC tubes).

The smallest size for a vessel containing 500m2 membrane (required: 72 m2 FDC) surface isobtained with 450 heaters diam. 26 (minimal FDC size), leading to 450 membranes diam.180, finally leading to a vessel of approximately 4m diameter (tubes of 2m length)

Case 2: a square of 8 membranes surrounding each heater

The most appropriate, for what we know so far, is a pattern exhibiting a square surrounding of8 membranes around each FDC heater. lts immediate potentially inconvenient is thatmembranes seem unequally exposed to the heaters, but this assumption may have a smallenough effect to be neglected.

Then, here is a summary of relevant data for this example:

Membrane diameter: 20mmFDC heater diameter: 26mmTubes length: 2,5mDeltaT:300degKMembrane area required: about 500m2

FDC area (depending on delta T and membrane area): about 72m2

The gap (distance between two tubes) between a heater and a membrane is set at itsminimum: 12.7mmThe gap between two membranes varies from 12.7mm to 15.7mm (range: 12.7 to 25.4mm)

After making it fit a 2.5 diameter vessel:Effective membrane area: for a vessel limited at 2.5m diameter, -503 m2 (-3208 membranes)Effective FDC area: -82 m2 (401 FDC tubes)

31

Available space (for catalyst) in between tubes: ~10.28m3

Amount of catalyst needed: 1.36m3

Schemes:

Figure 6 • FDC/membranes square arrangement

32


Figure 7a - situation in the vessel

33

Figure 8 - situation in the vessel

Case 3: other placement, minimising space

The IHeater + 8 Membranes square is a bit redimensioned to slightly change the placement inthe vessel and arrange all the tubes as close as possible.

With this arrangement,Effective membrane area: 519m2, 3304 membranes in the 2.5m large vessel.Effective FDC area: -84 m2,413 FDC tubes ui the vesselAvailable space (for catalyst) in between tubes: ~9.12m

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Figure 9 - more compact pattern

35

Figure 10 - 2.5m large vessel with best disposition

In order to limit the lost space, we reduce the diameter to 2400mm, and remove/replace theoutside membranes.Thus, the new characteristics are:Effective membrane area: 527 m2,3358 membranes in a 2,4m large vesselEffective FDC area: -84 m2,413 FDC tubes in the vesselAvailable space for catalyst: 8.12 m3

Needed space for catalyst: 1.36 m3

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Figure 11 - slight changes to minimim lost space

37

3.6.2 Disposition summary:

Principle

1 Membranesurrounding 1heater

8 membranessurrounding eachheater

membranes

353membranesdiam180mmlength 2m

3358membranesdiam 20,length2.5m

Membranearea

500 m2

527 m2

heaters

353heatersdiam26mmlength2m

413FDCtubesdiam26,length2.5m

Heatersarea

72m"

84m2

free space

22m3,onlywithin themembrane, not evenin thewholevessel.

8.12m3inthe wholevessel

benefits

Requiredmembranesurface can fita reasonablysized vessel,with a moreacceptablefree space

Disadvantages

Too largeamount of spacelost in betweenmembranes andheaters, whichare moreover toofar from eachother to have anefficiënt heatdistribution.Complexarrangement,leading to aprobablycomplex set up.


The catalyst packed bed can be mixed with pellets of an inert material without decreasing itsperformance, thus allowing us to fill the vessel and compensate the free space left.

Figure 12-1 FDC heater surrounded by membranes

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3.6.3 Vessel dimensions:

Based on the necessary capacity of the vessel's central part (2.5 high and 2 Am diameter) andon the working conditions of the reactor (pressure, feed components, temperature) we makethe choice of a material (SA-240 XM-19) via the ASME database and dimension the vessel'scentral cylindrical shell.The thickness determined is 62 mm.

CyUndrtcal Shell:Shell Material :Int Temperature(C):Int Preasure(ban):Corroslon AJIow. :

VESSELSA-240 XM-19600.00050.0005.000

62.000

T /

24

i

^ i

10.00

24

t \

\ '

0.0002524.

f ,

1

100

r

r 2500.00 .,

Dlmenilon Unhs: CodeCale2004

Figure 13 - central shell

See more in appendix 6: material choice and vessel thickness determination

39

3.6.4 Reactor schemes:

The disposition of all tubes in a module was done as shown on the following picture of themodule.

l Heating Fuel

Pre-heated air

Sweep gas

Figure 14 - reactor general view

The above presented reactor is about 6,2m high, but the highness of the rings up and under thereaction central part could eventually be reduced.

40

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Here is an open representation, showing how membranes and heaters are disposed, and whatthe different paths for each product are.

lllll_ Pre-heated gas• introduction chamber

l_ Sweep introductionl chamber

llilIllllllll

Flue gas collectionchamber —

Reactionchamber

Ha + sweep (Na)collection chamber

Figure 15 - open view of the reactor

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Chapter 4: Conclusions and discussion: •

The use of hydrogen selective membrane reactor is expected to have a considerable impact in _energy savings and CO2 emission reduction in dehydrogenation reactions, power production •plants, and ammonia and methanol production.The amount of current projects on hydrogen membrane reactors proves how the idea is .expected to go further. Our concept could match the expectations of industrial processes lmentioned above, but some points remain to be developed further.

It consists of a cylindrical vessel containing tubular membranes, tubular heaters and catalyst •pellets in a reaction chamber. Additional cylindrical chambers up and under the reaction oneare used for the distribution and collection of different streams. H

The membranes used are palladium-alloy membranes coated on a porous metallic tubularsupport. m

The reactor designed in this project does not have definitive dimensions. The reaction part ofthe module containing membranes and heaters has a convenient size, in regards to the 500m2 •of membrane area that fits in. But whereas the membranes, heaters outer tubes, and central |part of the shell dimensions are well defined, some parts of the overall reactor must beoptimized to reduce the overall size of the reactor. For instance, intermediary rings highness; •inlets and outlets diameters; nozzles size; bolts number and dimensions; and size of the |flanges. A major point would be to decrease the highness of a module, and consequently itsweight and price. •

Besides, the use of tubular heaters disposed among the membranes in the reaction part of thereactor is a promising solution; the most adequate heating fuel and oxidant have now to be Bdetermined, as the best size and distribution of nozzles on the inner tube. l

The montage of such an ensemble of tubes is inspired of the tubular heat exchangers Btechnology, meaning that tubes are welded on their ends (on one end for the inner heater Btube).

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ll• Acknowledgment:

Via this report I would like to thank the persons who helped me along this part of the• internship.

At ECN, Yvonne Van Delft, my supervisor, Frans Rusting, and the people from the• Engineering department. Henk Van Veen, who introduced me at ECN and to the EEI

department.

• At the hogeschool, Lex Baart for his support and his advices and Anton Honders for hispresence along this year

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APPENDIX: |

lAppendix 1: previous reactors concepts, sketches and drawings •Appendix 2: Flameless Distribution Combustion tubes |Appendix 3: functions table and assessment tablesAppendix 4: suitable catalysts •Appendix 5: amount of tubes (membranes and FDC) per module |Appendix 6: material choice and reactor parts dimensioning

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Appendix 1: Previous reactor concepts, sketches and drawings.

1. Catalytic membrane reactor that is used for the decomposition of hydrogensulphide into hydrogen and sulphur and separation of the products of saiddecomposition.

Espacenet ref: EP1411029

• Single porous ceramic membrane element

Catalyst in the form of athin layer or microlayerdeposited on the tubularceramic porousmembrane, maybe moreconvenient fordesulphurization thanusual catalysts.— ------ j

5: feed, wich is 400 to 700°C, and 0.5-1 atm. I didn't find no words about sweep or vacuüm

• several parallel porous ceramic membrane elements

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2. palladium membrane reactor using Ni catalyst for fusion fuel impuritiesprocessing

link:http://public.lanl.gov/willms/Papers/Performance_of_a_Palladium_Membrane_Reactor

_Using_a % 20Ni_Catalyst_for_Fusion_Fuel_Impurities_Processing.pdf

«ECTWIT5

•iujUESS STEL REIOCR «URETENTATE

The 3 points along the membrane are thermo-wells to measure the membrane surfacetemperature. ft i§ mounted in an MDC Corp."Del-Seal" flange, 53.8 mm dia. x 11.9 mm thick,304 stainless steel. This flange facilitates easy removal of the tube from the reactor shell.Catalyst is typically packed to within about 25 mm from either end. Theremaining spaces are filled with stainless steel wool. The permeate is pumpedout. The whole reactor is enclosed in a furnace, which is mounted vertically anduse three independently controlled heaters to maintain uniform temperature.

46

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3. Apparatus and process for high purity hydrogen production

Espacenet ref: WO2004022480

FQCFLUSGAS FDCFWE04S

l9

CO. W,)

Schematic diagram of amulti-tubular, FDC(flameless distributioncombustion) heated, radialflow, steam reformingmembrane reactor. Someof the inlet and outletstreams of the membraneFDC tubes have beenomitted for simplicity.

47

4. Schematic diagram of another embodiment of the FDC membrane reactor


'flt——r\2: FDC heater section3: inner permeate section4: catalyst section8: membrane9: catalyst15: inert bed.Feed enters via 5.Sweep, if used, enters via 6.Fuel for FDC heater enters at 14 the fuel tubes10.At 7 enters preheated air, nozzles in the tubes 10allows mixing with air and contol of heatdistribution along the section 2.Flue gas exits at 11.Effluents from catalysts/retentate exits at 13Permeate exits at 12.

a

J-T-H

5. Multi tubular, FDC heated, axial flow, membrane steam reforming reactor


Vaporizable hydrocarbon and steam enter via inlet 69 and flow through catalyst bed 70, containingmembrane tubes 71 and FDC tubes 72. feed and reaction gases flow from the top to the bottom.Membrane tubes closed at the top and a sweep gas enters via inlet 85 and flows upward. Permeate andsweep gas flow then downward and exit via outlet 86.

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The FDC tubes72 are closed-ended tubes with preheated air entering via inlet 76, fuel entering viainlet 77, and combustion gas (i.e. flue gas) exits via outlet 80

FIG.1

8S K

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6. Gas reactor with ceramic membrane

Espacenet ref: EP0962442A1

10

~ PRODUCT GAS70

W-96

36

20

16e

Body 12 thermally isolated from the high interior temp by insulation!2a, like 14/14a and16/16a at the top and bottom.62: catalyst

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11• 7. Reactor for reformation of natura! gas and simultaneous production of hydrogen

— Espacenet ref: US2003 17 1442

11

1 (&l \&:

> "-"i Ti

N.

\

* I/~W\

%\ TT Pl^"^/ ^

2: f eed inlet (with water vapor in this case)

1 3: oxygen-enriched air supply4: catalyst free burner for heating of the mix5: packed-bed catalyst (nickel on alumina or calcined Ni-hydrotalsite)

1 6: membranes7: hydrogen outlet

I There is no further detailed drawings and it seems that the inventors didn't clearly decideabout the sense of membrane separation. Both cases are mentioned in the description.

11111111

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8. Membrane reactor (only comments in japanese)

Espacenet ref: JP2003277009

m u

imn

CB21

[94]

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ll• 9. Tokyo reactor:

I Link:http://www.mhi.co.jp/mcec/product/membrane.htm

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Appendix 2: FDC tubes •

Main Information taken from espacenet patent number WO2004022480 •

Flameless Distnbuted Combustion (FDC) tubes provide great improvements in heat exchange .efficiency and load-following capabilities to drive the steam reforming reaction. Similar •efficiency and load-following is simply not possible with conventional firebox steam reformerfurnace designs and multi-reactor shift units. The FDC heat source makes it possible to Mtransfer between 90 and 95% of the heat to the reacting fluids. l

Principle: g

FDC chamber provides distributed, controlled heat flux to the reforming catalyst bed. A FDC •chamber comprises an inlet and a flow path for an oxidant, and an outlet for combustion gas. |The chamber also comprises a fuel conduit (tubular in our case) to the flow path of theoxidant. The fuel tube can have a plurality of openings or nozzles sized and spaced all along •its length, so that the amount of fuel mixing with the air or oxidant in the annular part of the |FDC section can be controlled to achieve the desired heat distribution along the heating area.The air (or another oxidant) is pre-heated to such a temperature that when the fuel and oxidant •are mixed in the FDC chamber, the temperature of the resulting mixture will exceed its own |auto-ignition temperature and start the combustion.Fuel quantity is controlled by nozzle size, the temperature rise is very small, and there is no •flame associated with the combustion (combustion is kinetically limited, rather than mass- mtransfer limited).Therefore, heat is distributed throughout the reactor at high heat fluxes without high •temperature flames and with low NOx production. B

lDrawings:

» 1&~*,^ iv, * «. *„** ~i~ t>wu~u.H..„, „„.51 «u*»» ~ ~,—————^ v~iv———. *~~ . ~^~„ wi««~.

FDC tubular chamber.The FDC tubes may be closed ended with a fuel conduit, oxidant inlet and flow path, and flue •gas outlet arranged as shown in Figure 10A. Or they may be open ended with the fuel conduit, *oxidant inlet and flow path arranged as shown in Figure l OB.

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Referring to Fig.lOA, an oxidant (in this case preheated air) enters the FDC tube at inlet 76and mixes with fuel which enters the FDC tube at inlet 77 and passes into fuel conduit 78through nozzles 79 spaced along the length of the fuel conduit. The combustion gases, (i. e.,flue gas) exit the FDC tube at outlet 80.In the "open ended" FDC tubular chamber shown in Fig. 10B, preheated air enters the FDCtube at inlet 76 and the fuel at inlet 77, and the fuel passes through conduit 78 and nozzles 79,similar to "closed end" FDC tube in Fig. 10A. However, in the case of the "open ended" FDCtube, the flue gas exits the FDC tube at open end 81, instead of outlet 80 as shown in Fig.lOA.

Disposition in a cylindrical reactor:

Figures 9 and 12 are top cross-section views of the shell of a multi-tubular, FDC heated,radial flow, membrane, steam reforming reactor.On figure 9, the cross sectional view of the reactor shows multiple membrane tubes 71 andmultiple FDC tubes 72 dispersed in catalyst bed 70 with optional hollow tube or cylinder 75being in the center of the reactor. In the example shown, the membrane tubes 71 have out-side diameters (OD) of about one inch while FDC tubes have an OD of approximately two

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inches, although other sizes of these tubes can be suitably employed. If a sweep gas isemployed, the membrane tubes 71 may contain an outer sweep gas feed tube and an innerreturn tube for sweep gas and hydrogen as shown in Figures 12 and 14. A larger shellcontaining more tubes duplicating this pattern can also be used.

FIG.12

hi the embodiment shown in figure 12, multiple membrane tubes 71 and multiple FDC tubes72 are dispersed in reforming catalyst bed 70. The multiple FDC tubes employed in thisembodiment are "closed ended". The membrane tubes are equipped with an outer sweep gasfeed tube and an inner hydrogen, sweep gas return tube.

Features:

The size of the FDC tubes can vary from about l inch (2.54 cm) OD up to about 40 inches(lm) or more OD.

It can be scaled down to a mobile, lightweight or lab-scale unit.

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In general the ratio of FDC tube surface area to membrane tube surface area will be in therange of about 0.1 to about 20.0, particularly from about 2.0 to 5.0, still more particularlyfrom about 0.3 to about 3.0, and even more particularly from about 1.0 to 3.0.

Each FDC tube or chamber will have at least one fuel conduit disposed therein. Larger FDCchamber generally will have multiple fuel conduits. The FDC tubes or chambers may be openended or closed ended.

The FDC tubes (as the membranes) may be surrounded by a cylindrical screen to protect themfrom direct contact with the catalyst, and allowing for instance to insert a tube in the reactoralready filled by the catalyst bed.

Length: For a given surface area, the cheapest heater is obtained by making it as small indiameter and as long as possible.Pitch: TEMA (tubular exchanger manufacturers association) specifies that the tubepitch/outside diameter ratio should not be less that 1.25mm and for external fouling servicethere should be a minimum gap of 6.35mm between adjacent tubes to assist extemal cleaningby mechanical means

Heat is removed along the length of the combustion chamber, so that a temperature ismaintained that is significantly below what an adiabatic combustion temperature would be.This almost eliminates formation of NOX, and also significantly reduces the metallurgicalrequirements, thus permitting the use of less expensive materials for construction of theequipment.

FDC tubes don't have hot spots that might damage the membranes.

For fuels such as methanol, pre heating to a temperature above about 800°C is sufficient.

FDC makes it easier to tailor axial heat flux distribution to minimize entropy production orenergy loss, and thus, make it more efficiënt.

FDC permits a more compact reactor design that is less expensive to build.

FDC permits a modular reactor design, in a wide range of sizes and heat duties.

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Appendix 3: function table and assessment tables •

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FUNCTIONS

1 shape of the shell

2 membrane disposition

3 heat input

membrane diffusiondirection

5 flow feed/sweep

6 catalyst

7 feed mixing

8 turbulences medium

feed flow over themembrane

10 entrance feed

14 manifold distributionsweep/permeate

SOLUTIONS

0°0

concentric cldpcles

Interrnsturner

Ninner to outerside

co-current

packed

parallel single/

ti

OD Oiangle

FC C tubes

o inner; idje

kthin layeronk. membrane

surface

extern

extern f urnace

no sweep(vacuüm)

parallel crossed

pre-heated gas

speed

parallel counter

concept A

concept B

concept C

concept D

/ / /

Radial

Functions table

59

Evaluation table:

Use:Safety is mainly related to membrane security, subject to harsh intern conditions, as startup.Membrane surface tells how much membrane area a concept can make fit in a volume (thevessel).Via startup are taken into account the heat provider and the material used for the membrane,because of possible thermal shocks when starting.Partial load tells how much subparts like membranes can be submitted to harsh loads.

Fabrication:Standard components: the use of a minimum of components is better.The evaluation of size pressure vessel is done considering the minimal size that the reactorcan reach.Tolerance is mainly related to membranes placement and moving during operating the reactor.The mass production capacity of this reactor depends on the number of fine parts or expensivepart of the reactors, like the thin layer of catalyst on each membrane surface.Mounting is also related to

243322

210,7

344334

280,9

122111

100,3

213322

180,6

444444

321,0

2

2

table 5 - assesment table

60


table 6- assesment table Y. Van Delft

4

4

61

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Appendix 4: catalyst available •

* The amount of SR and WGS catalysts for a Membrane reactor, which are necessary to meet •those typical requirements: 95% CHU conversion at 500 °C and 40bar, are not readilyavailable in literature, simply because there is still much research going on and to be done. «- However, here is an estimate for SR, based on a paper by Laegsgaard-J0rgensen et al. [Cat. l

Today 25 (1995), 303-307]: They use an amount of -3 kg catalyst per m2 membrane surfacearea. ^- For WGS, about 4 kg per m2 membrane would be required [A. Criscuoli et al., J. Membrane I

Science 181 (2001) 21-27]. w

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lFigure 16 - catalyst pellets

* The type of catalyst for ammonia synthesis used is typically Fe (metallic) with potash (K)and metaloxides (e.g., K2O + MgO + CaO + A12O3 + SiO2 +..., see Catalyst Handbook (2nd _ed), M.V. Twigg (Ed), Wolfe Publishing Ltd, 1989). J

* For methanol synthesis usually ZnO or Cu/ZnO are used on a metaloxide support (Cr2O3 or pA12O3 for instance). •

* For propane dehydogenation, supported Cr-oxide and supported Pt are used. m

* Typical pellet sizes are 2-4mm for SR (communication with N. Modi, Süd-Chemie) and 5-9mm for WGS and NH3 synthesis (Catalyst Handbook). mPrices of SR catalysts may vary from 100 to 800 €/liter, the catalyst for WGS costs about 10 |to 20 €/liter (l liter ~ l to l .5 kg). It is assumed, based on the fact that the components aresimilar, that the catalysts for the other reactions are in the same price range as WGS of 10-20 •€/l, except for the Pt-catalyst for propane dehydrogenation, which is probably closer to the SR |catalyst price of 100-800 €/l (most probably closer to 100 than 800 €/l).

lDensities of some SR catalysts and WGS catalysts should be similar.

62l

l

lll ICI:

I KATALCO 23-4 - 1 1 00 kg/m3

KATALCO 23-4M - 1200 kg/m3

KATALCO 23-4G - 1 1 00 kg/m3

• NIO 1 8 wt% SiO2 <0. 1 wt% SOS <0.05 wt% Support Balance (AI2O3)

UNICAT:

| NGR-61 2-3K - Bulk Density : 1 .05 kg/liter

NiO : 15-18%, K20: 5-6%, Balance Specialty alumina carrier. SIO2 : 0.2%.

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Appendix 5: amount of tubes per module:

A. Membranes

Tubes dimensions:Assuming that stainless steel tubes have the same range of dimensions that ceramic ones:OD = 10.5 mm (supplier) to 14 mm (ECN)Length = 1200 mm (supplier) or 1000-2500 mm (ECN)

500 m2:

64



number of tubes for a membrane surface of 500m2 per module

3'Si

- L = 1000-L = 1250L =1500

-L =1750-L = 2000-L = 2250-L =2500

10 11 12 13 14 15 16 17 18 19 20 21 22

tube diameter

Fout! Ongeldige koppeling.

450 m2:

65


-L= 1000-L =1250L= 1500L= 1750-L = 2000-L = 2250-L = 2500

10 11 12 13 14 15 16 17 18 19 20 21 22

tube diameter

400 m2:

66

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1300012000

2000

-L=1000-L=1250L =1500-L= 1750-L = 2000-L = 2250-L = 2500

10 11 12 13 14 15 16 17 18 19 20 21 22tube diameter

67

B. FDC tubes:

for 500 m2 membrane area

451441424409395382327286

269263253244236228196171

194190183176170164141123

361353340327316306262229

216211203196189182156137

15515214614113613211399

68



Appendix 6: material choice and reactor parts dimensionning

A. Vessel central part thickness and material

Input Echo, Component l, Description: VESSEL

Design Internal Pressure PTemperature for Internal PressureUser Entered Minimum Design Metal Temperature

Include Hydrostatic Head Components

Material SpecificationMaterial UNS NumberAllowable Stress At TemperatureAllowable Stress At AmbientYield Stress At TemperatureJoint efficiency for Shell Joint

Design Length of SectionLength of Cylinder for Volume Calcs.Inside Diameter of Cylindrical ShellMinimum Thickness of Pipe or Plate

Corrosion Allowance

50.00 bars600.00 C20.00 C

NO

SSASyE

L.ENDT

SA-240 XM-19S20910128.50197.200.000.85

2500.00002500.00002400.000062.0000

N. /mm2N. /mm2N. /mm2

mm.ILIlll .

mm.mm.

CA 5.0000 mm.

Skip UG-16(b) Min. thickness calculation NO

Type of Element: Cylindrical Shell

INTERNAL PRESSURE RESULTS. SHELL NUMBERASME Code, Section Vin, Division l, Ed-2001, A-03

1. Desc.: VESSEL

Thickness Due to Internal Pressure (TR):= (P*(D/2+CA)) / (S*E-0 .6*P) per UG-27 ( c ) ( 1 )= (50 .00*(2400 .0000/2+5.0000) ) / (128 .50*0 .85-0 .6*50 .00)= 56.7212 mm.

Max. All. Working Pressure at Given Thickness (MAWP):= ( S * E * ( T - C A ) ) / ( ( D / 2 + C A ) + 0 . 6 * ( T - C A ) ) per UG-27 ( c ) ( 1 )= (128 .50*0 .85*(57 .0000) ) / ( (2400 .0000 /2+5 .0000)+0 .6*57 .0000)= 50.24 bars

Maximum Allowable Pressure, New and Cold (MAPNC):= (SA*E*T)/(D/2+0.6*T) per UG-27 ( c ) ( 1 )= (197 .20*0 .85*62 .0000) / (2400 .0000/2+0.6*62 .0000)= 83.99 bars

Actual stress at given pressure and thickness (Sact):= ( P * ( ( D / 2 + C A ) + 0 . 6 * ( T - C A ) ) ) / ( E * ( T - C A ) )= (50.00*((2400.0000/2+5.0000)+0.6*(57.0000)))/(O.85*(57.0000))= 127.89 N./mmJ

SUMMARY OF INTERNAL PRESSURE RESULTS:Required Thickness plus Corrosion Allowance, TrcaActual Thickness as Given in InputMaximum Allowable Working Pressure MAWPMaximum Allowable Pressure, NC MAPNCDesign Pressure as Given in Input P

61.7212 mm.62.0000 mm.50.239 bars83.994 bars50.000 bars

69

HYDROSTATIC TEST PRESSURES (Measured at High Point):Hydrotest per UG-99(b); 1.3 * MAWP * Sa/S 100.22 barsHydrotest per UG-99(c) ; 1.3 * MAPNC 109.19 barsPneumatic per UG-100 ; l.l * MAWP * Sa/S 84.80 bars

Percent Elongation per UHA-44 ( 50t/Rf * (1-Rf/Ro) ) 2.518 %

WEIGHT and VOLUME RESULTS, ORIGINAL THICKNESS:Volume of Shell Component VOLMET 0.1199E+10 mm.**3Weight of Shell Component WMET 91115.2 N.Inside Volume of Component VOLID 11309.7 LitersWeight of Water in Component WWAT 110855.4 N.

WEIGHT AND VOLUME RESULTS, CORRODED THICKNESS:Volume of Shell Component, Corroded VOLMETCA 0.1104E+10 mm.**3Weight of Shell Component, Corroded WMETCA 83937.4 N.Inside Volume of Component, Corroded VOLIDCA 11404.2 LitersWeight of Water in Component, Corroded WWATCA 111781.1 N.

CodeCalc 2004 ©1989-2004 by COADE Engineering Software

70



71

B. Head thickness determination:

Input Echo, Component 3, Description: HEAD

Design Internal Pressure PTemperature for Internal PressureUser Entered Minimum Design Metal Temperature


Material SpecificationMaterial UNS NumberAllowable Stress At TemperatureAllowable Stress At AmbientYield Stress At TemperatureJoint efficiency for Head Joint

Inside Diameter of Elliptical HeadMinimum Thickness of Pipe or Plate

Corrosion Allowance

Aspect RatioLength of Straight Flange

50.00 bars600.00 C20.00 C

NO

SA-240 XM-19S20910

S 128.50 N./mm2SA 197.20 N./mm2Sy 0.00 N./mm3E 0.85

DT

CA

ARSTRTFLG

2400.0000 mm.62.0000 mm.

5.0000 mm.

2.0000220.0000 mm.

Skip UG-16(b) Min. thickness calculation

Type of Element:

INTERNAL PRESSURE RESULTS. SHELL NUMBERASME Code, Section VIII, Division l, Ed-2001, A-03

NO

Elliptical Head

3. Desc.: HEAD

Thickness Due to Interna! Pressure (TR):= (P*(D+2*CA)*K)/(2*S*E-0.2*P) Appendix 1-4(c)= (50.00*(2400.0000+2*5.0000)*!.00)/(2*128.50*0.85-0.2*50.00)= 55.4169 mm.

Max. All. Werking Pressure at Given Thickness (MAWP):= (2*S*E*(T-CA))/(K*(D+2*CA)+0.2*(T-CA)) per Appendix 1-4 (c)= (2*128.50*0.85*(57.0000))/(l.00*(2400.0000+2*5.0000)+0.2*(57.0000))= 51.42 bars

Maximum Allowable Pressure, New and Cold (MAPNC):= (2*SA*E*T)/(K*D+0.2*T) per Appendix 1-4 (c)= (2*197.20*0.85*62.0000)/ ( l .00*2400.0000+0.2*62.0000)= 86.15 bars

Actual stress at given pressure and thickness (Sact):= ( P * ( K * ( D + 2 * C A ) + 0 . 2 * ( T - C A ) ) ) / ( 2 * E * ( T - C A ) )= (50.00*(1.00*(2400.0000+2*5.0000)+0.2*(57.0000)))/(2*0.85*(57.0000))= 124.95 N./mm2

Warning: The operating yield stress or Elastic Modulus was outof Range. Please check the input carefully. Therequirements ofApp l-4(f) could nol be checked.


60.4169 mm.62.0000 mm.51.422 bars86.152 bars50.000 bars

71

72

WEIGHT and VOLUME RESULTS, ORIGINAL TfflCKNESS:Volume of Shell Component VOLMET 0.5553E+09 mm.**3Weight of Shell Component WMET 42202.7 N.Inside Volume of Component VOLID 1809.6 LitersWeight of Water in Component WWAT 27492.1 N.Inside Vol. of ***** mm. Straight VOLSCA 995.3 LitersTotal Volume for Head + Straight VOLTOT 2804.8 Liters

WEIGHT AND VOLUME RESULTS, CORRODED TfflCKNESS:Volume of Shell Component, Corroded VOLMETCA 0.5105E+09 mm.**3Weight of Shell Component, Corroded WMETCA 38799.3 N.Inside Volume of Component, Corroded VOLIDCA 1832.3 LitersWeight of Water in Component, Corroded WWATCA 27796.2 N.Inside Vol. of ***** mm. Straight, Corr. VOLSCA 1003.6 LitersTotal Volume for Head + Straight Corroded VOLTCA 2835.8 Liters

72

ll

HYDROSTATIC TEST PRESSURES(Measured at High Point): |Hydrotest per UG-99(b) ; 1.3 * MAWP * Sa/S 102.58 barsHydrotest per UG-99(c) ; 1.3 * MAPNC 112.00 bars _Pneumatic per UG-100 ; l.l * MAWP * Sa/S 86.80 bars •

Percent Elongation per UHA-44 ( 75t/Rf * (1-Rf/Ro) ) 11.110 %

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CodeCalc 2004 o1989-2004 by COADE Engineering Software •

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C. Summary for shell/head:

Description

VESSELHEAD

Minimum MAWP

MAPNCbars

83.86.

83.

994152

994

Note: Reqd. thk. reported above

TotalTotalTotalTotalTotal

Shell/HeadShell /HeadShell/HeadShell/HeadShell/Head

weightweightweightvolumevolume

MAWP Tr-intbars mm.

50.239 61.72151.422 60.417

50.239

Tr-ext EMAWPmm. bars

———

--

-

-

includes Corrosion Allowance.

is (New-Cold)is (Corroded), filled with Water (New)is (New-Cold)is (Corroded)

13331712273627166537283761

.9

.6

.5

.7

.8

N.N.N.galsgals

Least MAWP and Overall Weight Results :The Least MAWP (N C) for VESSEL was 83.99 bars .The Least MAWP (Cor) for VESSEL was 50.24 bars .

The total sum of the Weights ( N C ) was 133317.94 N.The total sum of the Weights ( Cor ) was 122736.63 N.

CodeCalc 2004 ©1989-2004 by COADE Engineering Software

73

D. FDC extern tubes determination:

Cylindrical Shell: TubeShell Material : SA-312Int Temperature(C): 898.000Int Pressure(bars): l .000

Ext Temperature(C): 600.000Ext Pressure(bars): 50.000

2.000

tK ' 2500.00

26.00022.000

V \

t '————— 3H 1

,^

Dimension Units: mm. CodeCalc 2004

Input Echo, Component l, Description: Tube

Design Internal Pressure PTemperature for Internal PressureUser Entered Minimum Design Metal TemperatureDesign External Pressure PEXTTemperature for External PressureExternal Pressure Chart Name


Material SpecificationMaterial UNS NumberAllowable Stress At TemperatureAllowable Stress At AmbientYield Stress At TemperatureJoint efficiency for Shell Joint

SSASyE

Design Length of Section LLength of Cylinder for Volume Calcs. CYLLENOutside Diameter of Cylindrical Shell DMinimum Thickness of Pipe or Plate TNominal Thickness of Pipe or Plate T

1.00898.0020.0050.00600.00HA-6

NO

SA-312S308154.93

171.680.001.00

2500.00002500.000026.0000

barsCCbarsC

N./mm2N./mm2N./mm2

00000000

imn.mm.,mm.mm.mm.

Corrosion Allowance CA 0.0000 mm.

74



Skip UG-16(b) Min. thickness calculation NO

Type of Element: Cylindrical Shell

INTERNAL PRESSURE RESULTS. SHELL NUMBER 1. Desc.: TubeASME Code, Section VIII, Division l, Ed-2001, A-03

Thickness Due to Interna! Pressure (TR):= (P*D/2)/(S*E+0.4*P) per Appendix 1-1 (a)(1)= (1.00*26.0000/2)7(4.93*1.00+0.4*1.00)= 0.2615 mm.= 1.5875 mm. ( Per Ug 16b )

Max. All. Working Pressure at Given Thickness (MAWP):= (S*E*(T-CA))/(D/2-0.4*(T-CA)) per Appendix 1-1 (a)(1)= (4.93*1.00*(2.0000))/(26. 0000/2-0.4*2.0000)= 8.08 bars

Maximum Allowable Pressure, New and Cold (MAPNC):= (SA*E*T)/(D/2-0.4*T) per Appendix 1-1 (a)(1)= (171.68*1.00*2.0000)/(26.0000/2-0.4*2.0000)= 281.44 bars

Actual stress at given pressure and thickness (Sact):= ( P * ( D / 2 - 0 . 4 * ( T - C A ) ) ) / ( E * ( T - C A ) )= ( l . O O M ( 2 6 . 0 0 0 0 / 2 - 0 . 4 * ( 2 . 0 0 0 0 ) ) ) / ( ! . 0 0 * ( 2 . 0 0 0 0 ) )= 0 . 6 1 N./mm2


HYDROSTATIC TEST PRESSURES ( Measured at High Point):Hydrotest per UG-99(b); 1.3 * MAWP * Sa/SHydrotest per UG-99(c); 1.3 * MAPNCPneumatic per UG-100 ; 1.1 * MAWP * Sa/S

Percent Elongation per UHA-44 ( 50t/Rf * (1-Rf/Ro) )

1.5875 mm.2.0000 mm.8.084 bars

281.435 bars1.000 bars

365.87 bars365.87 bars309.58 bars

8.333 %

EXTERNAL PRESSURE RESULTS. SHELL NUMBERASME Code, Section vm, Division l, Ed-2001, A-03

1. Desc.: Tube

External Pressure Chart HA-6 at 600.00 CElastic Modulus for Material 148791.59 N./sq.mm.

Results for Max. Allowable External Pressure (Emawp):Corroded Thickness of Shell TCA 2.0000 mm.Outside Diameter of Shell OD 26.0000 mm.Design Length of Cylinder or Cone SLEN 2500.0000 mm.Diameter / Thickness Ratio (D/T) 13.0000Length / Diameter Ratio LD 96.1539Geometry Factor, A f(DT,LD) A 0.0065089Materials Factor, B, f(A, Chart) B 69.7362 N./mm2Maximum Allowable Working Pressure 71.52 barsEMAWP = (4*B)/(3*(D/T)) = ( 4 * 69.7362 )/( 3 * 13.0000 ) = 71.5243

Results for Reqd Thickness for Ext. Pressure (Tca):Corroded Thickness of Shell TCAOutside Diameter of Shell OD

75

1.4765 mm.26.0000 mm.

Design Length of Cylinder or Cone SLENDiameter / Thickness Ratio (D/T)Length / Diameter Ratio LDGeometry Factor, A f(DT,LD) AMaterials Factor, B, f(A, Chart) BMaximum Allowable Working Pressure

2500.0000 mm.17.609196.1539

0.003547566.0433 N./mm250.01 bars

2.000026.0000

0.3555E+1113.0000

0.1367E+100.006508969.736271.52

mm.mm.mm.

N. /mm2bars

EMAWP = (4*B)/(3*(D/T)) = ( 4 * 66.0433 )/( 3 * 17.6091 ) = 50.0069

Results for Maximum Length Calculation: No ConversionCorroded Thickness of Shell TCAOutside Diameter of Shell ODDesign Length of Cylinder or Cone SLENDiameter / Thickness Ratio (D/T)Length / Diameter Ratio LDGeometry Factor, A f(DT,LD) AMaterials Factor, B, f(A, Chart) BMaximum Allowable Working PressureEMAWP = (4*B)/(3*(D/T)) = ( 4 * 69.7362 )/( 3 * 13.0000 ) = 71.5243

SUMMARY of EXTERNAL PRESSURE RESULTS:Allowable Pressure at Corroded thickness 71.52 barsRequired Pressure as entered by User 50,00 barsRequired Thickness including Corrosion all. 1.4765 mm.Actual Thickness as entered by User 2.0000 mm.Maximum Length for Thickness and Pressure 0.3555E+11 mm.Actual Length as entered by User 2500.00 mm.

WEIGHT and VOLUME RESULTS, NO CA.:Volume of Shell Component VOLMET 376991.0 mm.**3Weight of Shell Component WMET 0.0 KN.Inside Volume of Component VOLID 950331.8 mm.**3Weight of Water in Component WWAT 0.0 KN.

CodeCalc 2004 ©1989-2004 by COAOE Engineering Software

76


ll

Reference:

• E.M. van Dorst, H.M. van Veen: THE APPLICATIONS OF HYDROGEN-SELECTIVE MEMBRANES IN INDUSTRIAL PROCESSES, ECN-CX—02-061, June

• 2002.

H.P. HSIEH, INORGANIC MEMBRANES FOR SEPARATION AND REZACTION,M 1996.

Y.C. van Delft, P.P.A.C. Pex, MEMBRANES FOR HYDROGEN PRODUCTION,• ECN-RX—04-016, Septembr 2003.

_ A.m. Adris, T. Boyd, C.Brereton, PRODUCTION OF PURE HYDROGEN BY THE• FLUIDIZED BED MEMBRANE REACTOR, 14* world hydrogen energy world

conference, Montreal, June 2002.

l R.Birksteiner, MICROPOROUS CERAMIC MEMBRANES FOR GAS SEPARATIONPROCESS, contract JOE3-CT95-0018, September 1998.

l R. Buxbaum, MEMBRANE REACTORS, FUNDAMENTAL AND COMMERCIALADVANTAGES, KG. FOR METHANOL REFORMING, REB research and

• consulting, March 2004. www. Rebresearch.com

B. C. Gates, H. Knözinger, ADVANCES IN CATALYSIS, volume 47

l G.F. Hewitt, HEAT EXCHANGERS DESIGN HANDBOOR, volume 1-4

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ECNHet Energieonderzoek Centrum Nederland in Petten is een zelfstandige marktgerichteorganisatie voor onderzoek, ontwikkeling, dienstverlening en kennisoverdracht openergiegebied. Ruim 600 medewerkers voeren opdrachten uit van het bedrijfsleven en deoverheid. ECN ontwikkelt en vermarkt technologieën voor een veilige, efficiënte enmilieuvriendelijke energiehuishouding. De units van ECN werken aan duurzameenergie (zon, wind, biomassa en duurzame energie in de gebouwde omgeving), energieuit fossiele brandstoffen, energie-efficiency en beleidsstudies. ECN is een innovatiefkennisbedrijf en actief in projecten over de hele wereld. Bij alle activiteiten kiest ECNduurzame ontwikkeling als leidraad.

Het werk op het gebied van nucleaire energie en stralingstechnologie (ook: medischetoepassingen) wordt uitgevoerd door NRG, de joint venture van ECN (70%) en KEMA(30%), waarin deze organisaties hun nucleaire expertise hebben gebundeld. Bij NRGwerken circa 300 medewerkers.

EnergieonderzoekCentrumNederlandWesterduinweg 3Postbus l1755 ZG PettenTelefoon: (0224) 56 49 49Telefax: (0224) 56 44 80E-mail: [email protected]://www.ecn.nl/


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