Purified Water SystemsEquipment and Design Overview

Pure H2O Technologies 211 Warren Street Newark, NJ 07103 www.ipureh2o.com

Instructor: Robert Marsiglia

Water

Water Is “The Universal Solvent” As Well As “The Fundamental

Building Block Of Life”.

Effective High Purity Water Treatment Must Address Both To

Be Successful.

Water Contaminants

Suspended Solids – Rocks, Gravel, Sand,pH – High or LowDissolved Ions – SaltsBacteriaPyrogens – Residue of CellsOrganic Carbon

Pure Water Criteria

99% Of All High Purity Water Treatment Has Three Specific Objectives For End Purity:

Ionic Purity – Measured By TDS, Resistivity Or Conductivity

Viable Organism Purity – Measure By “Total Plate Count” Test

Organic Purity – Measured By T.O.C. Testing

Pure Water

Pure Water Is Defined Differently By Different Industries And Regulatory Agencies USP – Pharmaceutical Industry

Purified Water Water For Injection

ASTM Grades Of Water For Manufacturing, Power Utilities And Testing Labs Type I Type II Type III Type IV

SEMI Grades Of Water For Electronics And Semiconductor Manufacturing ASTM Grades Of Water For Electronics And Semiconductor Manufacturing

Type E-I Type E-II Type E-III Type E-IV

College Of American Pathologists Water Standards For Laboratories CAP I CAP II CAP III

What is Pure Water And How Do I Define Exactly What My Requirements Are???

Sample Water Standard

D1193‐91 Standard Specification for Reagent Water

1.1 This specification covers requirements for water suitable for use in methods of chemical  analysis and physical testing. Four grades are specified: 

Type I Type II Type III Type IV Electrical conductivity  0.056  1.0  0.25  5.0, max,  uS/cm at 298 K (25° C)

Electrical resistivity  18.0  1.0  4.0  0.2, min,  megohm‐cm at 298 K(25° C)pH at 298 K (25° C)  NA  NA  NA  5.0 to 8.0Total organic carbon, ug/L 50  50  200 no limit (TOC), max Sodium, max, ug/L  1 5  10  50Chlorides, max, ug/L  1  5 10  50 Total silica, max, ug/L 3  3 500 no limitEndotoxin Units (EU)         <0.03        0.25         N/A             ‐‐‐‐‐‐‐‐‐‐

User defined water requirements lead to the proper selection of equipment for:

Pretreatment Primary Purification Storage and Distribution (“Polishing”)

Component Selection

Pre‐Treatment Filtration & Media Components Cartridge Filters Multimedia Filters Sand Filters Carbon Filters Water Softeners Neutralizing Filters Iron Removal Filters Chemical Injection Units

Designed to Treat Inlet Water Conditions

Traditional Pure Water Pretreatment Equipment

Pretreatment UnitBooster Pump, Multimedia Filter, Water Softener, Carbon Filter

Primary Purification  Equipment(Membrane & Ion Exchange Components) Reverse Osmosis UnitsUltra‐filtration UnitsNano‐filtration Units Electrodeionization Units Ion Exchange Units (Fixed & Service DI Units) Gas Membrane Units

Traditional Pure Water Processing Equipment

Combination RO ‐ EDI Units

Pure Water Treatment Operations

Water Softener– Removes Hardness From Supply Using Ion Exchange.

De-chlorination (Carbon) – Removes Oxidizing And Organic Compounds Using Adsorption.

Reverse Osmosis Module – Removes 99% Of Ions, Organisms and Organic Compounds (MW Greater Than 150 – 200)

MBDI/Electrodeionization - Removes Ions Using Exchange Resin, or a Combination of Resin, Membranes and Electricity.

UV Sterilization – Destroys Viable Organisms Using Ultraviolet Radiation.

Ion ExchangeSoftening and De‐Ionization Depicted

Softening – Exchanges Sodium Ion For Calcium And Magnesium Ions In Water Stream.

Calcium And Magnesium Ions Easily Complex With Other Ions Typically Found In Water And Can Form Scale.

Scale Readily Deposits On Surfaces (Especially RO Membrane Surfaces) And Can Reduce Operational Efficiency.

Regeneration Of Ion Exchange Resins Extremely Important.

AdsorptionCarbon Media Filtration

Binds Oxidizing Compounds (Chlorine) And Organic Molecules To The Surface Of The Media.

Prevents Oxidization Of The Membrane Surfaces Used In Downstream Processes.

Oxidation Quickly Reduces The Effectiveness Of Membranes In Removing Small MW Compounds. Oxidation “Eats Holes Into The Membrane Surfaces”

Maintenance of Carbon Media Extremely Important To Unit Performance And Membrane Life.

Reverse Osmosis

Reveres Osmosis – Excludes Ions, Organisms And Organic Compounds Greater Than 200 MW.

Significantly Concentrates Contaminants Commonly Found In Water By “Transporting” The Water Out And Rinsing Away The Remaining Contaminates.

Not 100% Efficient…typically 65% to 75% Efficient. Feed Water equipment must be sized accordingly.

Electrodeionization

Electrodeionization – Effectively Removes Ions Using A Combination Of Ion Exchange And Membrane Technologies.

Mixed Bed Ion Exchange Resin Used To “Capture” Cations And Anions In Water Stream. Resins “Conduct” These Captured Ions To The Positive Or Negative Terminals Of A DC Field Through “Ion Selective” Membranes.

Resins Act Like A “ Wire” In The Transport Of Ions.

Chambers Extremely Thin In Order To Maintain Current Flow. Requires Pretreated Water For Effective Operation.

Electrical Current Continually “Regenerates” Ion Exchange Resins.

Electrical Current Minimizes Biological Growth With The Dynamic Areas Of The Cell. Minimal Maintenance Required.

EDI Technology

Mixed Bed Service De‐ionization

System Storage Tank Distribution Pump(s) UV Sterilization Units (Standard and “TOC Reducing”) Final Filter Units Distribution Loop Instrumentation Sanitization Modules

Traditional Pure Water Storage/Distribution Equipment

System Storage Tank

Distribution “Polisher” Schematic

Several Designs: Simplex or Duplex Alternating 2/3 or 100% redundancy Vertical Multi‐Stage Sanitary Design Horizontal Single Stage Centrifugal Standard or Variable Frequency Drives Remember NPSH relative to Tank Height

Distribution Pumps

254 nm Wavelength Unit for Bacteria Sterilization

185 nm Wavelength Unit for Bacteria and TOC reduction

Intensity Monitors available in Analog and Digital Format

UV Sterilization Units

Select filtration level according to Water Quality Requirements

Typical USP Final filter is 0.2‐micron Some ASTM Standards require tighter levels of filtration for TOC and Endotoxin Control

Final Filter Assembly

Loop Supply and Return Quality (Resistivity) System Temperature Flow Rate (can also be used to control Pump VFD’s) TOC on‐line monitors Pressure (Indicators and Transmitters)

Distribution Loop Instrumentation

Distribution “Polisher” UnitPumps, UV, and Final filters etc…

Determine “daily” water consumption What is a “day”? Average water usage over day period Maximum water draw (volume and frequency) Space allotment  for Storage “Ideal” design – Storage = Daily Usage “Not ideal” – RO generation relative to maximum 

draw and tank size

Generation Design Considerations

* Ideal: 1500 gallons/12 hour day usage…12 hour “off‐time”1500 gallon Storage capacityRO Generation = 1500/720 = ~ 2 GPM

* “Not ideal”:1500 gallons/12‐hr day usage, 750 gallon storage500 gallons max draw in 1 hour (once/day AM)~ 90 gallons/hour average usageIs 2 GPM OK?

Generation Sizing Examples

Is 2 GPM OK….YES2 GPM x 60 = 120 gallons;  500‐120 = 380 gallons750‐380 = 370 gallons remainingNext hour: 120 – 90 = 30 gallon net gain (400 gallons)

More difficult situation:Max draw more than once per day500 gallon draw 2 x day (6 hours apart)~ 50 gallons per hour average usage GPM 

Is 2 GPM still OK?

Generation Sizing Examples

Is 2 GPM still OK….YESAfter hour one, 370 gallons remainAfter hours 2 through 5, we have gained 280 gallons (4 hours  x 70 gallons net gain)Start of hour 6…640 gallons of storageAs before, the net loss of 500 draw is 380After hour 6, 280 gallons remain

Generation Sizing Examples

Distribution Loop Design Individual Floors (Riser and Return)Serpentine (continuous)Overall Pressure Loss

Location of Distribution Equipment Determine desired minimum velocity at maximum use Max draw determines Non‐use Flow rate

Distribution Sizing Considerations

500 gallon maximum draw in hour = 8 GPM Also consider maximum “instantaneous” draw Pump Skid increments 10, 20, 30, 40 GPM etc..

Polypropylene Pipe 40 mm (1‐1/4”)Desired velocity in System during max draw:  ~ 2‐3 ft./sec20 GPM, 40 mm pipe: 4.9 ft./sec 12 GPM remains at ~ 3 ft./sec

Must Consider:Pressure Drop per 100 ft. of pipeMay need to increase pipe size due to loop length (Example, 40 mm Pressure loss is 3.23 PSIG per 100 ft.)

Distribution Sizing Example 

Determine Proper Equipment from User Requirements Obtain Daily Water Usage Information Determine Storage Size Available Size RO per Storage and Maximum Draw Determine Loop Design, pressure and flow rate Select Distribution Skid for acceptable Velocities at minimum and maximum water draw rates

Design Review

Questions

How can we help in the Design of your Pure Water System