Air Connection on Rack. Filtrate Connection on Rack

Transcription

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2 What is a membrane?

3 Module with Flow holes

4 Air Connection on Rack Filtrate Connection on Rack

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7 1 module 1rack

8 Goal is to use membranes to separate or filter solids, organisms, and molecules from the liquid stream

9 Reverse Osmosis Nanofiltration Ultrafiltration Microfiltration Transmembrane Pressure Decreasing Pore Size Increasing Membrane Separation Process Reverse Osmosis Nanofiltration Ultrafiltration Microfiltration Size of Common Materials Salts Carbon Bk. Paint Pigments Human Hair Pyrogens Sand Metal DNA, Viruses Bacteria Mist Ions Vitamin B12 Tobacco Smoke Coal Dust Sugar Colloids Dust Red Blood Pollens Atoms Cells Flour Particle Type Macro Ions Molecules Molecules Micro Particles Macro Particles Micrometers (Log Scale)

10 Large Suspended Particles Macromolecules Smaller Particles Divalent salts Monovalent salts Water MF UF NF RO Micro filtration (MF) - bacteria, algae, clay, large MW humic acids Ultra filtration (UF) - humic acids, viruses, protein Nanofiltration (NF) viruses, divalent salts Reverse Osmosis (RO) monovalent salts

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13 Separation device like a clarifier to separate suspended solids from the water Physical barrier: suspended solids bigger than pore size remain in the process tank Mixed Liquor MLSS 5,000 14,500 mg/l Flow Permeate TSS < 1mg/l Turbidity < 0.2 NTU

14 MBR market is expanding fast Many different MBR manufacturers 3 main ones Zenon Owned by GE USFilter Owned by Siemens Kubota Each manufacturer has its own design

15 USFilter Zenon Kubota Type Hollow Fiber Hollow Fiber Flat Sheet

16 SpiraSep: Ashbrook Toray: Kruger, Smith & Loveless, Aquatech Nadir: Huber Hydranautics: Mitsubishi Koch/Puron: ITT Sanitaire, Aqua-Aerobic

17 USFilter Zenon Kubota Pore Size 0.04 m 0.04 m 0.4 m Membrane Surface Area 340 ft ft 2 of Smallest Replaceable 405 ft 2 Per 500d module Per Cartridge Unit Membrane Area per Plan 400 ft 2 /ft ft 2 /ft ft 2 /ft 2 Area Flow per Plan Area 6,000 gpd/ft 2 5,000 gpd/ft 2 2,000 gpd/ft 2 Membrane Material PVdF Reinforced PVdF Chlorinated Polyethylene Average Flux 15 gfd 15 gfd 15 gfd Vacuum < 7.3 psi < 11.9 psi < 3.0 psi

18 Wastewater: Eliminates sludge settleability issues Reduced sludge yield Excellent nutrient removal capability Water and Wastewater: Fewer process steps to achieve comparable effluent quality Small Footprint Modular expansion capability High quality effluent Low effluent turbidity Uncompromised effluent in upset conditions

19 Backwash Screen Coagulation Flocculation Sedimentation Filtration Backwash Strainer Membrane Tank + Membrane Racks

20 Sludge Holding Activated Sludge Clarifier Sand Filter Integrated Membrane Bioreactor Activated Sludge Membranes Sludge Holding

21 Fine screening Typical MBR Layout Anoxic Basin Aeration Basin Membrane Operating System Membrane Operating System

22 Mixed liquor overflow & grease removal Air to membranes Mixed liquor to membranes

23 Permeate Partitioned fiber bundles Narrow fiber bundles provide excellent fluid transfer within entire module Air mixed liquor scouring of delivery slots Air Mixed liquor

24 Membrane Fiber 1 fiber Process Mixed Liquor Airlift Cross Flow Cross Flow Cross Fl low Permeat te Permeate Cross Flow Permeate Perme ate Cross Flow

25 Key Factors: Flux- Flow across membranes per membrane surface area (gfd = gpd/ft2 or LMH = L/h/m2) Transmembrane Pressure - TransMembrane Pressure, pressure across the membrane surface (in psi or kpa) Membrane Surface Area Total surface area over which water is filtered Resistance Factor dictating pressure differential across membrane

26 Q = Permeate Flow, gpm F = Flux = gpm/ft 2 A = Area, ft 2 ΔP = Transmembrane Pressure, psi F = Flux, gpm/ft 2 R = Resistance, psi/(gpm/sf)

27 R = Resistance, psi/(gpm/sf) σ = Permeability, (gpm/sf)/psi

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29 Maintenance Procedures Relaxation Backpulse Maintenance Clean CIP Air Leak Testing Ability to predict turbidity breakthrough Ability to predict turbidity breakthrough, identify source, and repair

30 Completely Automated Every 12 minutes to reduce solids buildup on membrane surface 60 s duration Filtrate pumps are stopped Relieves solids tension on membrane surface so they are scoured away Air Filtration Air Relaxation

31 Completely Automated t Using periodically to reduce solids buildup on membrane surface Reverse flow utilizing i filtrate pumps Air Air Filtration Backwash

32 Completely Automated Every 1-2 week(s) Air is On or Off Mixed liquor pump is stopped Mixed liquor remains in tank Protocol: Backwash with chlorine (200 mg/l) Relaxation for 15 minutes Air Air minutes duration Inhibits biological surface fouling Backwash with chlorine Relaxation

33 Chlorine Automated no membrane removal Every 3 months or if TMP > 5 psi at average design flux or permeability < 3.2 gfd/psi CIP 4-24 hours 4-24 hours per membrane cell Mixed liquor is sent back to biological tanks Utilizes chlorine at approximately PvDF Oxidant- Resistant Fibers 1,500 mg/l Occasional acid cleans for inorganic Air Air fouling Used CIP solution is wasted or recycled within the plant (job specific) Chemical Clean & recirculation Chemical Clean & Soak

34 Critical for Drinking Water Facilities Effluent turbidity data Test: Visual Air pressure

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38 Needed to control pathogen levels Disinfection versus sterilization 9/30/2008

39 Characteristics of a good disinfectant 1. K 2. N 3. N 4. E 5. C 6. E 7. R 9/30/2008

40 Common Disinfectants Less Common Disinfectants 9/30/2008

41 CT Concept 9/30/2008

42 Kinetics of Disinfection Follows C -W Law 9/30/2008

43 Indicator Organisms Organism that is part of Organism that is present when f is present The number of indicator organisms is the pathogenic organism Same s character in environment as target pathogen Organism must not be d to reproduce or enumerate Isolation must be f & more e than target pathogen 9/30/2008

44 Forms of Chlorine 1. C 2. H 3. O 9/30/2008

45 9/30/2008

46 Reactions of Chlorine 9/30/2008

47 Reactions of Chlorine 9/30/2008

48 Reactions of Chlorine 9/30/2008

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50 Chlorine Decay 9/30/2008

51 Chlorine Residual 9/30/2008

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