Membrane Technology - culligan.com.ar · – Immersed MBR. Advantage and Disadvantage of Flat sheet...
Transcript of Membrane Technology - culligan.com.ar · – Immersed MBR. Advantage and Disadvantage of Flat sheet...
4/04/13
Membrane Technology
PURPOSE PROCESS PAYOFF
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§ PURPOSE: PROVIDE AN OVERVIEW OF MEMBRANE TECHNOLOGY.
§
§ PROCESS: REVIEW MEMBRANE TYPES AND CHEMISTRIES
§ REVIEW MARKET APPLICATIONS
§ PAY-OFF UNDERSTAND DIFFERENT MEMBRANE TYPES
§ ABILITY TO IDENTIFY MORE MEMBRANE APPLICATIONS
What are Membranes?
§ Thin barriers or films of material that allow certain substances to pass through.
§ Our bodies have numerous semi-permeable membranes that allow nutrients in and toxins out.
Semi-permeable membranes only allow some substances to pass through
Membrane Element
Construction
Materials of Construction
§ Organic– Cellulose Acetate– Thin Filmed Composite– Polypropylene– PVDF– Polyamide– PAN– PES
§ Inorganic– Ceramic– Metallic oxide/Stainless Steel– Zirconium oxide/Carbon
Materials of Construction
§ The material used in the construction have process limitations (pH, temperature etc.) These limitations will determine the type of applications the module can be applied.
§ Membranes are selected based on their compatibility to the stream they are treating.
Materials of Construction
§ Organic– Limited pH range for cleaning and operating
• varies from 2 to 12 for commercial membranes– Limited temperature range for cleaning and
operating• max 120 F for most commercial membranes
§ Inorganic– Wide pH operating and cleaning
• 1 - 14– High operating and cleaning Temperature
• 220 F
Materials of Construction
§ Organic– More commercially available– Lower replacement cost– Limited Life
§ Most applications where pH is less the 12 and greater then 2 and temperature is bellow 120O F.
Materials of Construction
§ Inorganic– Becoming more commercially available– High replacement cost– Easily cleaned– Theoretical Unlimited Life
§ Applications:– High or low pH less then 2 and greater the
12.– High temperature or steam sterilize
requirements
Membrane Element
Configurations
Flat Sheet Modules
Reverse Osmosis
– Food processing(old model)
Ultrafiltration
– Food processing– Immersed MBR
Advantage and Disadvantage of Flat sheet Construction
• Advantages- process high solids loading- good hydraulic flow behavior
• Disadvantages- not back flushable- low package density- difficult to clean.- limitation of plate size - sludge deposition at the boundary of plate
Hollow Fine Fiber Membranes
Microfiltration
Ultrafiltration
Seawater ROLarge strawsSmall straws Feed
Large fibers for microfiltration
Smaller fibers for UF & RO
UF in outor out in
Feed Product
Concentrate
RO out -in
Hollow Fiber Fine Membranes§ Advantages
– Very compact, limited floor space, high packing density.
– High permeate flows– Commercially available
§ Disadvantages– Modules are Susceptible to fouling– Effective cleaning is difficult (small spaces)– Difficult to detect membrane imperfections– Extensive pretreatment required– Viscous feed solutions containing high
concentrations of suspended solids tend to foul module and make it difficult to clean.
Hollow Fiber Applications
Reverse Osmosis
– Seawater desalinization(old model)
Ultrafiltration
– ED paint– Immersed MBR– Bacteria and Virus Removal– Immersed Drinking water
Permeate
Air
feed
Immersed Hollow Fiber For MBR
Tubular Membranes
Smallest pores
Membrane supportLarger pores
Feed
Product
Concentrate
Tubular Crossflow Velocity
Tubular Membranes
§ Advantages– Suitable configuration and chemistries for
wastewater– Easily cleaned by mechanical or hydraulic or
chemical procedures.– Multi-tube modules make it easy to replace
membranes– High Tolerance for Suspended solids– Commercially available
§ Disadvantages– High hold up volume– Membrane density low, Large floor area required– Pumping costs are high because of high fluid
velocities required.
Tubular Applications
Reverse Osmosis
– Specialty Food applications• Juice• Dairy
Ultrafiltration
– ED paint– External MBR– Oily wastewater– Juice Clarification– Inorganic precipitation processes (metals, softening)
– Textile wastewater
P e r m e a t e
F e e dp u m p
R e c i r c u l a t i o np u m p3 , 5 - 4 , 5 m / s
5 m
W a s t e w a t e r B e r g h o f F l o wB i o
B I O -R e a c t o r
Spiral Wound RO Module (Element)
Feedwater
Permeate flows spirally toward collection tube
Permeate Out
Concentrate
Concentrate
Permeate carrier
Feed flow across spacer
Covering & bypass spacer
Feed-channel spacer
Membranes
Perforated collection tube
Anti-telescopingdevice
Spiral Wound RO Flow Pattern
Spiral Wound Membranes
Advantages– High Packing Density– Module Hold-up volume is small– Modules easy to replace– Medium Range Tolerance for Suspended solids– Commercially available
Spiral Wound Membranes
Disadvantages
– Traditionally small flow channels are susceptible to fouling, new wide spacer configuration are now available.
– Dead end spaces make it difficult to clean– Membrane chemistry/glues/backing are limited– Not easily cleaned by hydraulic or chemical
procedures
Spiral Wound Applications
Reverse Osmosis/Nanofiltration
– Water Treatment• Demineralization Brackish and Seawater• Organics Removal –Nanofiltration
– Specialty Food applications• Juice• Dairy
– Wastewater– Metals concentration– Leachate– COD/BOD removal/polishing– Chemical Recovery
Spiral Wound Applications
Ultrafiltration
– Water Treatment• Polishing UF• Light Surface water
– Specialty Food applications• Juice• Dairy
– ED Paint
Hollow Fiber Capillary Membranes
Hollow Fiber Capillary Membranes
§ Advantages– Combine the benefits of both hollow fiber and
tubular configurations– Very compact, limited floor space, high packing
density.– High permeate flows– High solids loading– Commercially available– Backwash capability– Single chemistry, single structure, no delamination– Low energy
Hollow Fiber Capillary Membranes
§ Disadvantages– Modules are Susceptible to fouling with high solids
loading
Membrane Applications
– 3000 ppm of cutting fluid oils (20,000 gallons per day). Looking to reduce volume hauled away and to discharge permeate.
– Landfill leachate containing High TSS, Dissolved organics, COD and TDS that requires treatment prior to discharge.
– 2% Total solids of cheese whey. Looking to concentrate for animal feed and produce effluent of low BOD for discharge.
– Wastewater from existing biological treatment plant with clarifier, looking to reuse water back in manufacturing facility.
QUESTIONS
QUESTIONS?