Chang-Han Yun / Ph.D.
Hankyung University
June , 2015
Chapter 5. Membrane Filtration Process
2 Membrane Filtration Process Hankyong National University
Contents
1. Membrane Separation Process
5. Waste Water Reuse
4. Desalination
3. Reverse Osmosis(RO)
2. Filtration Membrane
Contents Contents
6. Reference for Industrial WW Reuse
3 Membrane Filtration Process Hankyong National University
1. Membrane Separation Process
1. Filtration Membrane
6. Membrane Reactor
4. Facilitated Transport Membrane
3. Membrane Contactor
2. Dialysis Membrane
Membrane
Processes Membrane
Processes
7. Bio Membrane
5. Permselective Membrane
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Filters Pore Size
(㎛)
Separation
Mechanism Application
Operating
Pressure(bar)
Particle Filter(PF)
Roughing Filter(RF) 5.0 ∼ 1,000 Sieving SS removal 0.03 ∼2.0
Micro Filter(MF) 0.05 ∼ 5.0 Sieving
(Porous)
Colloid/Bacteria
removal 1.0 ∼ 5.0
Ultra Filter(UF) 0.05∼0.005 Sieving
(Porous)
Colloid/Virus
removal 1.0 ∼ 5.0
Nano Filter(NF)
0.001
∼
0.005
Solution-diffusion-
imperfection
(Non-porous)
Salt(>+2)
rejection
5.0 ∼ 10.0
Hyper Filter(HF)
Reverse Osmosis(RO)
Forward Osmosis(FO)
0.00005
∼
0.0005
Solution-diffusion-
imperfection
(Non-porous)
Salt(>+1)
rejection 10.0 ∼ 70.0
Filtration 1. Membrane Separation Process
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Dialysis
Membranes
Characteristics Separation
Mechanism Application
Retentate Permeate
Size Comp.
Dialysis Macro Solutes
Micro Minor
(solvent)
Sieving and
hindered diffusion Acid, Alkali
(>0.02㎛)
Hemo-
Dialysis (HD) (0.005㎛) 〃 〃 〃 Artificial kidney
Donnan-
Dialysis (DD) Charged ions 〃 〃 Ion-exchange
Pretreatment of
desalination
Metal recovery
Electro-
Dialysis (ED)
Co-ions,
Macro-ions,
Water
Micro
(ions) Minor 〃
Desalination
Chloro-Alkali
Electro-Dialysis
Reversal (EDR) 〃 〃 〃 〃 〃
Dialysis 1. Membrane Separation Process
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Membrane
Contactors
Characteristics Separation
Mechanism Application
Retentate Permeate
Size Comp.
Membrane-based
Solvent Extraction
(MSE/MSX)
Solvent
Less soluble Minor
More
soluble
Solubility
difference
Organic pollutants removal
Olefin extraction
Metal recovery
Membrane
Stripping
(MS)
Water
Less soluble 〃
More
volatile 〃
Dissolved gas(air, NH3 etc)
free water
Membrane
Distillation
(MD)
Non-volatile Either
volatile
High volatility
and diffusion
Concentration of liquid
foods
Pore
Condensation
(PC)
Permanent
gas Minor Condensable
Pore condensation
and permeation VOC removal from gas
Membrane
Contactor 1. Membrane Separation Process
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Facilitated
Transport
Membrane
Characteristics Separation
Mechanism Application
Retentate Permeate
Size Comp.
Emulsion Liquid
Membrane
(ELM)
Water
Less soluble
/reactive
Minor
More
soluble
/reactive
Solubility difference
Reaction kinetics
Zn recovery in viscose rayon
Metal/Protein recovery
Phenol removal
Immobilized
Liquid Membrane
(ILM/SLM)
〃 〃 〃 〃
Metal/Protein recovery
Phenol removal
Acid gas removal
Contained Liquid
Membrane
(CLM)
〃 〃 〃 〃 〃
Facilitated
Transport 1. Membrane Separation Process
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Permselective
Membrane
Characteristics Separation
Mechanism Application
Retentate Permeate
Size Comp.
Gas Permeation
Membrane
(GPM)
Less soluble Either More soluble Solution-
diffusion
H2S removal in natural gas
CO2 recovery in flue gas
H2, He purification
N2, O2 enrichment
Vapor Permeation
Membrane
(VPM)
Permanent gas
Less soluble Minor More soluble 〃
Water vapor removal
VOC/VIC removal
Pervaporation
(PV) Less soluble 〃
More volatile
More soluble 〃
Alcohol/H2O separation
VCM recovery in
PVC synthesis process
Permselective 1. Membrane Separation Process
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㎛
Relative Size
of Common
Material
Molecular
Weight
0.001 0.01 0.1 1.0 10 100 1000
100 200 5,000 20,000 100,000 500,000
Aqueous Salt
Metal Ion
Filtration
Technology
Pyrogens
Virus
Colloidal Silica
Bacteria
Carbon Black Paint Pigment
Yeast Cells Beach Sand
Pollens
Reverse Osmosis
Ultra-Filtration
Micro-Filtration
Particle Filtration
Nano-Filtration
Soluble Removal
(Ions, COD) Colloid Removal SS Removal
SDI(0.05㎛) SS filter(1.4㎛)
Filtration
Spectrum 2. Filtration Membrane
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Membrane
Module
Tubular Spiral Wound
Hollow Fiber Plate & Frame
2. Filtration Membrane
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Module
Characteristics
Module type
Items Spiral wound Hollow fiber Tubular Plate & Frame
Typical Packing Density
m2(Area)/m3(Volume) 800 6,000 70 500
Required feed flow rate
(m/s) 0.25∼0.5 ∼0.005 1∼5 0.25∼0.5
Feed pressure drop
(kg/cm2) 3∼6 0.1∼0.3 2∼3 3∼6
Membrane fouling
propensity High High Low Moderate
Ease of cleaning Poor to good Poor Excellent Good
Feed stream filter size (㎛) 10∼20 5∼10 Not required 10∼25
2. Filtration Membrane
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Polysulfone
Spacer
0.2㎛
50㎛
120㎛
Support layer
Polyamide
(Active layer)
Support Layer(50㎛)+ Active Layer(0.2㎛)
Ion separation using reverse osmosis
Spiral Wound 2. Filtration Membrane
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Feed Spacer
Feed Spacer
Polysulfone
Product Spacer
0.2㎛
50㎛
120㎛
Support layer
Polyamide
(Active layer)
Product Spacer
Support Layer(50㎛)+ Active Layer(0.2㎛)
Ion separation using reverse osmosis
Spiral Wound 2. Filtration Membrane
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Hollow Fiber
Non-Braid Type
Braid Type
(Reinforced)
2. Filtration Membrane
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Hollow Fiber
Submergible Type Case Type
2. Filtration Membrane
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MBR
MBR : Membrane Bio Reactor
→ (Bio treatment + Membrane filtration) Reactor
2. Filtration Membrane
Raw WW
Anaerobic
Tank
Anoxic
Tank
Aerobic
Tank Membrane
Module
Pump Filtrate
Effluent
Filtrate
Tank
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MBR
Aerobic Bio Degradation
Bio
Pollutants(Org/T-N) + O2(Air) CO2 ↑ + H2O + Cell
Sludge
Blower Excess Sludge
WW
MLSS(Mixed Liquor Suspended Solid)
• MLSS of Conventional Activated Sludge : 1,500 ∼ 4,000 mg/L
• MLSS of Aerobic MBR : 4,000 ∼ 10,000 mg/L
MLVSS(Mixed Liquor Volatile Suspended Solid) : 70% of MLSS in general
SRT(Sludge Retention Time) : 20 ∼ 30 days in general
2. Filtration Membrane
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Fouling
Deposit → Remove through Flushing / Backwashing
Clogging
Cake Formation
Plugging → Recover by Using Backwashing / CIP (※ CIP : Chemical In Placed)
Fouling
La
yer
Cake Layer formed on the surface of membrane by deposition of SS in feed
Gel Not movable layer of soluble polymer formed on the surface of membrane by
concentration
Scale Insoluble hardness layer formed on the surface of membrane by concentration
Pore Blocking Block the pore inside by adsorption of organic or salting-out of inorganic salt
Path Blocking Block the path of feed stream in membrane module by SS
2. Filtration Membrane
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Fouling
Air Flushing : Continuous supply the air to the bottom of membrane frame
Backwashing by flowing-back the filtrate :
※ 0.5∼1.0 min. after every 20∼30 min. filtration(backwash flux = 1.5∼2.0 × filtration flux)
CEBW : Chemical Enhanced Back Wash(Backwashing using filtrate containing HOCl)
※ 1 time per day
CIP
※ 1 time per 3 months
To maintain stable operation, the efficiency of air flushing is most important.
To enhance the flushing effects
Module & Frame Structure → Optimization of aerator : air stream line, bubble size, volume
Roughness of Membrane Surface
2. Filtration Membrane
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Operating
Principle of RO
Osmosis Reverse Osmosis
Osm
osi
s
Low Salt
Solution
High Salt
Solution
Mem
bra
ne
Mem
bra
ne
ΔP
ΔP
- O
smo
sis
Low Salt
Solution
High Salt
Solution
3. Reverse Osmosis
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Salt and water
ΔP
water
ΔP
water
Salt
Reverse Osmosis
Operating Principle of RO
Water Desalination Cost
Operating
Principle of RO 3. Reverse Osmosis
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RO Membrane
Material
Poly-Amide
(PA)
Cellulose
(CA)Remark
2∼12 4∼6
15 30
TDS 99+ 98
SiO2 99+ 95
Stable Unstable
Production Rate Salt Rejection Performance Drop
Salt Permeability 30%↑ 100%↑
Salt Rejection 99% → 98.7% 98% → 96%
Very Low Low
High Low
Oxitant Resistance
Physico-Chemical Stability
Materials
Items
pH Range
Operating Pressure (kgf/cm2)
Salt
Rejection(%)
Fouling
Long Time Using
After 3 Years
Using
3. Reverse Osmosis
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RO Membrane
Rejection
NO Inorganic Rejection(%) MW NO Organic Rejection(%) MW
1 NaF 99 42 1 HCHO 35 30
2 NaCN 98 49 2 CH3OH 25 32
3 NaCI 99 58 3 C2H5OH 70 46
4 SiO2 99 60 4 Isopropyl Alcohol 90 60
5 NaHCO3 99 84 5 Urea 70 60
6 NaNO3 99 85 6 Lactic Acid(pH 2) 94 90
7 MgCl2 99 95 7 Lactic Acid(pH 5) 99 90
8 CaCl2 99 111 8 Glucose 98 480
9 MgSO4 99 120 9 Sucrose 99 342
10 NiSO4 99 155 10 Disinfectant 99 -
11 CuSO4 99 160 11 BOD 95 -
12 COD 97 -
3. Reverse Osmosis
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RO Membrane
Rejection
NO Cation Rejection(%) NO Anion Rejection(%)
1 Na+ 97 1 Cl- 99
2 Ca2+ 99 2 HCO3- 98
3 Mg+2 99 3 SO42- 99
4 K+ 98 4 NO3- 96
5 Fe3+ 99 5 F- 98
6 Mn2+ 99 6 SiO2- 99
7 Al3+ 99 7 PO43- 99
8 NH4+ 99 8 Br2+ 98
9 Cu2+ 99
10 Ni2+ 99
11 Zn2+ 99
12 Sr2+ 98
13 Cd+2 99
14 Ag+ 99
15 Hg2+ 99
3. Reverse Osmosis
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1. Rejection of inorganic > organic
2. Rejection of electrolyte > non-electrolyte
3. Valence↑ → Rejection ↑
4. Hydration number and ion size of inorganic ions ↑ → Rejection ↑
5. Molecular size of non-electrolyte ↑ → Rejection ↑
6. Gaseous salt, Gas(NH3, Cl2, CO2, O2, H2S) : low rejection
7. Weak acid : low rejection
※ Rejection of organic acid : Citric acid > Tartaric acid > Acetic acid
Characteristics
of RO 3. Reverse Osmosis
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Operation Mode
Permeate R O
Raw
Water
Tank
Raw Water
Concentrate
Boosting Pump
High pressure Pump
Batch
R O
Raw
Water
Tank
Continuous (Feed & Bleed)
R O
Raw
Water
Tank
R O
R O
Continuous (One-Through)
Permeate
Permeate
Concentrate
Concentrate
Concentrate
Concentrate
High Pressure
Pump
Boosting Pump
Boosting Pump
High Pressure
Pump Permeate
Permeate
Raw Water
Raw Water
3. Reverse Osmosis
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S/W for Simulation
of RO Block 3. Reverse Osmosis
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Reverse Osmosis(RO) 4. Desalination
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Reverse Osmosis(RO) 4. Desalination
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Reverse Osmosis(RO) 4. Desalination
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Reverse Osmosis(RO)
with Energy Recovery 4. Desalination
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Reverse Osmosis(RO)
with Energy Recovery 4. Desalination
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Reverse Osmosis(RO)
with Energy Recovery 4. Desalination
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Reverse Osmosis(RO)
with Energy Recovery 4. Desalination
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Reverse Osmosis(RO)
with Energy Recovery 4. Desalination
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Forward Osmosis(FO) 4. Desalination
Draw Solution
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Forward Osmosis(FO) 4. Desalination
Membrane Distillation
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Forward Osmosis(FO) 4. Desalination
Membrane Distillation
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Forward Osmosis(FO) 4. Desalination
Combination Process of Membrane(Hybrid System)
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Overview 5. Waste Water Reuse
WWTP
WW Sewage
Discharge
WWTP
(Existing)
Return(20~30%)
Reuse Plant
(New)
Reuse(70~80%)
1. Purpose
Reuse the effluent of the WWTP by treating up to industrial water quality.
Solve problems caused by water shortage at the dry season.
Design to be minimize the cost by adequate combination of the unit equipment.
Minimize the initial investment by connecting with existing the WWTP.
2. Concept
WW Sewage
Discharge
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Reverse Osmosis (RO)
Ion Exchange Resin (IX)
Electro Dialysis (ED or EDR)
3. Usage
4. Main Equipments
General purpose(Toilet, Landscape etc.) colloid/SS removal & disinfection by regulation
Replace industrial water colloid/SS, BOD, COD and ions removal
Separation processes are simple isolation of pollutants from water physically,
not vanish them. So, they basically have a problem that generate the concentrate
containing highly concentrated pollutants.
Overview 5. Waste Water Reuse
42 Membrane Filtration Process Hankyong National University
1st Pre-treatment(Remove particle)
▶ Screen
▶ Sand Filter(SF)
▶ Multi-Media Filter(MMF)
▶ Fiber Filter
2nd Pre-treatment(Remove soluble organic)
▶ Activated Carbon(AC)
▶ Advanced Oxidation Process(AOP)
3rd Pre-treatment(Remove Colloid)
▶ Micro Filter(MF)
▶ Ultra Filter(UF)
▶ Double Stage Fiber Filter
Safety Filter
▶ Cartridge Filter(1∼2 ㎛)
RO / NF(Salt rejection)
Filtrate to Service
Concentrate
(to WWTP)
Raw Water
Basic Concept
※ SDI : Silt Density Index
※ LSI : Langelier Saturation Index
☞ SDI < 5.0
☞ CODCr < 10 mg/ℓ
☞ LSI < - 0.1
5. Waste Water Reuse
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Process
Purpose : Pollutants removal to discharge the concentrate
Purpose : Produce ultra pure water(2nd de-ionized water)
Effluent
Discharge
(20~30%)
Pretreatment
Salt Rejection(IX/RO/ED etc.)
Advanced
treatment
Reuse
(70~80%)
Post treatment
Optional
Purpose : Protect the membrane from fouling
Target Pollutants : Organics, SS, Colloid, Scale etc.
Purpose : Produce industrial water(1st de-ionized water)
Target Pollutants : Dissolved salts/ions and organics
1. Pre-treatment
2. RO
3. Advanced treatment
4. Post treatment
5. Waste Water Reuse
44 Membrane Filtration Process Hankyong National University
Pre-treatment
Optional
Effluents from WWTP
Particle Filter (PF)
Granular Activated Carbon(GAC)
MF / UF Membrane
Disinfectants
RO Process Purpose : Stable pretreatment under 2.0 of SDI15
Purpose : Protect RO from organic fouling
Target Pollutants : Dissolved polymer and organics
Purpose : Protect RO from colloidal fouling
Equipment : SF, MMF, Fiber filters, etc.
Target Pollutants : SS, Colloid
1. Particle Filter(PF)
2. Granular Activated Carbon(GAC)
3. MF / UF Membrane
5. Waste Water Reuse
45 Membrane Filtration Process Hankyong National University
RO
Optional
Pretreatment
Safety Filter
Heat Exchanger
R O
Scale Inhibitor
Reductants
Reuse or Reuse after advanced treatment
CIP
Purpose : In-site chemical cleaning system of RO
Purpose : Emergency protection from colloidal fouling
Target Pollutants : Foreignbody from pipes and pumps
Purpose : Maintain minimum temperature of inlet water
for the stable recovery rate of RO permeate
Purpose : Reject the salts and ions from inlet water
Rejection Rate : Minimum 99%
1. Safety Filter
2. Heat Exchanger
3. RO (Reverse Osmosis)
4. CIP (Chemical In Place)
5. Waste Water Reuse
46 Membrane Filtration Process Hankyong National University
Permeate Quality
of RO
Items WWTP Effluents RO Permeate Industrial Water(IW)
pH 6 ~ 8 6 ~ 7 6 ~ 7.5
Conductivity (uS/cm) 1,200 ~ 4,000 < 50 60 ~ 200
COD (mg/L) 30 ~ 80 1 1
SS (mg/L) 10 ~ 60 0 1
Alkalinity (mg/L) 150 ~ 200 < 20 30 ~ 80
Hardness (mg/L) 60 ~ 100 < 5 40 ~ 120
Turbidity (NTU) 2 ~ 10 < 0.5 0.4 ~ 2
5. Waste Water Reuse
47 Membrane Filtration Process Hankyong National University
Investment
of RO
Equipment
(million ₩)
Unit Capital
(1,000 ₩/(m3/d))
※ Based on standard market price(2007)
5. Waste Water Reuse
48 Membrane Filtration Process Hankyong National University
Economic Comparison
Particle
FilterMF / UF Ozone RO
60 200 100 360
Electicity(50₩/kwh) 0.4 20 15 110
Chemicals 6 2 0 100
Maintenance 2.6 50 3 33
Total 9 72 18 243
17% PAC: 30mg/ℓ
Life time of filter
media : 3yrs
Life time of
membrane: 5yrs
Ozone Dose : 6mg/ℓ
Maintenance:
3%/yr of capital
Life time of
membrane: 3yrs
Operating
(₩/m3)
Remark
Unit Capital(1000 ₩/(m3/day))
Equipments
Items
※ Based on 5,000 m3/d capacity and standard market price(2007)
5. Waste Water Reuse
49 Membrane Filtration Process Hankyong National University
Economic Analysis
of Sewage Reuse
Items Price(million ₩) Remarks
Machinery
Pumps 750 Include HP Pump
Pretreatment 930
Activated Carbon Filter 700
MF / UF 2,500
RO 1,800
CIP System 65
Chemical Dose System 45
General Machinery 200
Sub-Total 6,990
Installation with Piping 750
Electricity and Control System 420
Engineering with margin 600
Total 8,760 584,000 ₩/(m3/d)
▶ Feed Q : 22,000m3/d, Permeate Q : 15,000m3/d(68% Recovery), Concentrate : 7,000m3/d
▶ Basis of raw water conductivity : 1,500 μs/cm
1. Initial Investment Effluent
(22,000 m3/d) AC UF RO
Reuse
68% Recovery
15,000 m3/d
5. Waste Water Reuse
50 Membrane Filtration Process Hankyong National University
Items Price Amount Cost(1000 ₩)
day month year
Pretreatment Filter Media 270 mil ₩/set 1 set/4yrs 188 5,625 67,500
Activated Carbon Filter 95 mil ₩/set 3 set/yr 792 23,750 285,000
RO Membrane 850,000 ₩/ea 936 ea/2yrs 1,105 33,150 397,800
C
H
E
M
CIP Inorganic Chemicals 10 mil ₩/set 1 set/month 333 10,000 120,000
Organic Chemicals 10 mil ₩/set 1 set/month 333 10,000 120,000
Filtration Auxiliary 50,000 ₩/kg 7.5 kg/d 375 11,250 135,000
Disinfectants 85,000 ₩/kg 3 kg/d 255 7,650 91,800
Anti-
foulants
Anti-scalants 85,000 ₩/kg 3 kg/d 255 7,650 91,800
Anti-organic foulants 85,000 ₩/kg 3 kg/d 255 7,650 91,800
Electricity 50 ₩/kwh 11 Mwh/d 550 16,500 198,000
Total (296 ₩/m3) 4,441 133,225 1,598,700
▶ Industrial Water Cost : 15,000 m3/d × 550 ₩/m3 × 360 d/yr = 2,970 million ₩/yr
▶ Save : about 1,300 million ₩/yr
2. Operating
Economic Analysis
of Sewage Reuse 5. Waste Water Reuse
51 Membrane Filtration Process Hankyong National University
Industry
Item Silicon Wafer Tire Automobile Can Manufacture Steel Manufacture Petro-Chemistry
Starting Date 1995 1995(?) 1996 1998 2002 2002
Background Lack of water No discharge permit No discharge permit Lack of water Replace city water Effluent regulation
Permeate of RO (m3/d) 880 180 2,000 525 10,000 3,128
Characteristics
of Raw Water
Wafer washing WW
High concentration of
peroxide
Fine particle
CODMn : 150 ppm
BOD : 95 ppm
SS : 120 ppm
N-H : 28 ppm
With sewage(1:1)
Cond.: 3,500 μs/cm
Hardness: 200 ppm
CODMn : 50 ppm
N-H : 90 ppm
TDS : 1,580 ppm
CODCr : 362 ppm
Floating Oil
Raw water:STP effluent
CODMn : 16∼28 ppm
Turbidity : 6∼14 NTU
NH3 : 980 ppm
CODMn : 80 ppm
Cond. : 7,000 μs/cm
Pre-treatment AC+MF+O3+UV+AC RSF+AC+ PF SF+AC+Cation Ex DAF+MMF+AC+UF MDF+MMF+VF MMF
SDI 4.0∼5.0 11.0 < 3.0
RO Recovery(%) 70 60 80 75 75 93
RO CIP(days) 90 28 14∼21 4.1∼7.3일
Investment(thousand ₩) 2,000,000 6,000,000 800,000 8,000,000
Unit Capital Cost
(thousand ₩/(m3/d)) 2,273 3,000 1,524 2,558
O
&
M
Fix(₩/day) 1,096
Labor(1000 ₩/day) 199
800
Direct Operation
(1000 ₩/day) 113
Sum(thousand ₩/d) 1,408
Unit Operation(₩/m3) 1,600 400 800
Remark
•MF CIP : 7days
•MF Rec. : 90∼95%
•#2 AC→ SDI 저하
•CF life time : 7days
•Organic SS
•No bio treatment
•Design :96% recovery
•CF life time : 15days
•CODCr : 4 ppm
•CF life time : 30days
•2 stage RO
•Evaporator include
•AC life time : 30days
•Dead-end UF
•No industrial water
•reused as cooling water
•RO life time : 2 months
•RO feed:1∼4 NTU
•3 stage RO
•Explosion design
•Concentrate : use
as a raw material of
fertilizer
▶ Unit Capital : Very High (> 1,000,000 ₩/(m3/d) )
※ Sewage effluent reuse by RO : < 600,000 ₩/(m3/d)
▶ No standard process flow for reuse of industrial WW
Analysis of Reference 6. Reference for Industrial WW Reuse
52 Membrane Filtration Process Hankyong National University
Characteristics
1. Raw waste water : Silicon wafer washing WW
2. H2O2 concentration in WW = 300 ppm → generate COD
3. Reuse to wafer washing(ultra-pure deionized water, >17 ㏁ )
4. Re-deionization of RO permeate through 2 stages of Mixed Bed
5. A part of COD was removed at activated carbon and O3/UV
6. Most of COD was removed at RO and Mixed Bed
7. Plant was constructed at Nov. of 1994 and operation was started
at Aug. of 1995
Items ① ② ③ ④ ⑤ ⑥ ⑦
Q(m3/d) 1,400 1,260 880
COD(mg/l) 200 10 10 0.5
TOC(mg/l) 30 4
Cond.(㎲/cm) 500 50
SS(mg/l) 80 30 0
SDI15 2∼2.8 2.8 Max. 4-5
Raw
WW
①
Reservoir → Cool
ing → AC#1
②
MF
③
Ozone
→ → →
↑ ↑ pH disinfection Concentrate
↑
↓ Concentrate ↓
Reuse ← MB
(#1+#2)
⑦
RO
⑥ Cartridge
Filter
⑤
AC#2
④
UV
← ← ← ←
Operation
1. Temperature : 25℃
2. MF operation cycle : 15 minutes
3. MF CIP cycle : 7 days
4. MF recovery rate : 90-95 %
5. RO feed pressure : 15 atm
6. RO array : 8" module(total 72ea)
- 1st stage : 6 elements/train×4 trains
- 2nd stage : (6 elements/train×2 trains)×2 sets
7. Cartridge filter life time : 7 days
8. RO CIP cycle : 3 months
9. RO recovery : 70 %
Silicon Wafer 6. Reference for Industrial WW Reuse
53 Membrane Filtration Process Hankyong National University
Specification of unit equipment
1. AC #1 : COD adsorption and degradation
- Original design : Bio-reactor using media
- H2O2 in WW(300 ppm) disturb attachment of bio organism
- Present status : Use only adsorption column
(Organic degradation by H2O2)
2. MF : Removal of SS
- Material : PP(Pore Size : 0.2㎛)
- Equipment cost : 700 million ₩
3. Ozone/UV : COD and TOC break-down
- Ozone generation : 1kg of O3/hr
- Ozone contactor size : 1.5 mΦ×5 mL
- DO of ozonized water : 20 ppm
4. AC #2 : Residual H2O2 breaking(Micro organism growth)
5. Cartridge Filter
- Pore size : absolute 20 ㎛ (normal 5 ㎛)
- Size : 4 "Φ×20 "L×19 ea×3 sets
6. RO system : TOC and Salt removal
- Feed pressure : 15 atm
- Design : 3 stage(high concentration) → Present : 2 stage operation
Economy Analysis
1. Capital Cost upto RO (880m3/d) : 2,000 mil ₩
2. Operation Cost : 1,600 ₩/m3(include labor)
※ 108 ₩/m3(utility, Media, Chemical)
☞ Total : 472.6 million ₩/yr
- Depreciation (10%/yr) : 200 million ₩/yr
- Interest(10%/yr) : 200 million ₩/yr
- Labor : 72.6 million/yr
(2.20 million ₩/mo/person ×3person×12mo)
Silicon Wafer 6. Reference for Industrial WW Reuse
54 Membrane Filtration Process Hankyong National University
SF AC #1 AC #2
ED
Permeate
(Reuse)
DD Al Electro
Coagulation DAF RSF Sludge
Sludge
①
Effluent
※ SF : Sand Filter
PF : Particle Filter(Marino Filter)
CF : Cartridge Filter
ED : Electro Dialysis
DD : Drum Dryer
RSF : Rapid Sand Filter
PF CF R O
Concentrate
② ③ ④ ⑤
Characteristics
1. COD Source : Carbon Black(SS)+Soluble Oil
2. SF+AC : Remove 5 ppm of COD
3. Design : 96% recovery upto ED,
(Concentrate : Evaporated by DD)
4. Present : Discharge concentrate(about 40%)
Items ① ② ③ ④ ⑤
Q(m3/d) 240∼300 ← ← ← 144∼180
BOD(mg/l) 95 4 1
CODMn(mg/l) 150 4 2.5 2.7 1.1
CODCr(mg/l) 3.5 4.0
SS(mg/l) 120 3 0.7 0.5
SDI5 12.5 11.0
N-H(mg/l) 28 0.5
TDS(mg/l) 1,500 81.5
Conductivity(㎲/cm) 2,000 95.9
Total Hardness(mg/l) 117 140 2
TOC(mg/l) 1,607
Turbidity(NTU) 2∼4
Operating Conditions
1. Temperature : 34℃
2. Cartridge filter life time : 15 days
3. RO CIP cycle : 28 days
4. RO recovery : 60 %
Tire Manufacture 6. Reference for Industrial WW Reuse
55 Membrane Filtration Process Hankyong National University
SFF AC Cation
Exchange
1st
Evaporator Sludge
Effluent
(2,000 m3/d)
※ SFF : Sand Flo Filter
CF : Cartridge Filter
VD : Vacuum Dryer
Heat
Exchanger
CF
(3㎛) 1st RO
Concentrate
2nd RO 2nd
Evaporator VD
Characteristics
1. Initial Plan : Discharge to sea(<CODMn 10 mg/l)
(Piping cost : 12 billion ₩)
2. Change Plan : No discharge(6 billion ₩)
3. Flow Rate including Sewage
- Design : 5,000m3/d(Sewage : WW = 1 : 2)
- Operation : 2,000m3/d(Sewage : WW = 1 : 1)
4. CODMn of Effluent : 50 mg/l(Raw : 300 mg/l)
5. Conductivity : 3,000~4,000μS/㎝
6. Total Hardness : max. 200 mg/l
Operation
1. Temperature : 25℃
2. RO Array
- #1 RO : Filmtec BW30 12:6:3×2 blocks(6 ea/vessel)
- #2 RO : Filmtec SW30 8×1 block(4 ea/vessel)
3. Pressure
- #1 RO : 13 atm, - #2 RO : 40 atm
4. RO Recovery
- Design : 95%, - Operation : 80%
6. CF life time : 30 days
7. RO CIP cycle : 2~3 wk(CIP Chemical : NaOH, Citric Acid)
8. Evaporator
- Design : Solidification by using 2 evaporator, Vacuum dryer
- Operation : Partial drain of concentrate
Economics
1. Investment : 6 billion ₩
2. Operation including labor :
- RO : 400 ₩/m3
- Evaporator : 400 ₩/m3
Automobile
Manufacture
Filtrate
(Reuse)
6. Reference for Industrial WW Reuse
56 Membrane Filtration Process Hankyong National University
DAF MMF 1st AC Permeate
(Reuse)
2nd AC
Raw WW
(700 m3/d)
※ DAF : Dissolved Air Floatation
MMF : Multi-Media Filter
UF R O
Concentrate
Discharge
Operation
1. AC life time : 30 days
2. SDI of UF Filtrate < 3
3. RO
- Temperature : 25℃
- RO Array : Filmtec BW30 3:2:1×1 block(6 ea/vessel)
- Pressure : 13 atm
- Recovery : 75%
Economics
1. Investment : 800 million ₩
2. Operation Cost : 800 ₩/m3
※ DAF+AC : 570 원/m3
Characteristics
1. Flow Rate : 700 m3/day
2. N-H : 90 mg/l
3. NBDCOD > 140 mg/l
4. After DAF
- N-H < 1 mg/l, - COD < 56 mg/l
5. SDI after AC : < 5.0
6. UF : Dead-End Type UF(BUF)
Items Raw
Water DAF MMF 1st AC UF RO 2nd AC
CODCr(mg/l) 362 142 135 10 10 5 32→18
CODMn(mg/l) 52 36 34 3 3 1 10→5
Turbidity(NTU) - 0.53 0.45 0.35 0.30 0.15 2.90→2.86
TDS(mg/l) 1,580 1,690 1,690 1,680 1,680 80 4,700→4,650
Can Manufacture 6. Reference for Industrial WW Reuse
57 Membrane Filtration Process Hankyong National University
Characteristics
1. Raw WW : Effluent of STP
2. Purpose of Reuse
Make-up of cooling water
Operation
1. Recovery : about 75%
2. Rejection : about 99.4%(1,651→9.8 ㎲/cm)
3. CIP cycle and RO life time
4. Serious fouling by colloidal and micro organism
5. Very unstable operation by low efficiency of pre-treatment equipment
RO Train
Items #1 #2 #3 #4 #5
Ave. CIP Cycle(day) 6.6 7.3 4.7 4.1 5.1
Ave. RO life time교체 33 ? 33 66 66
MDF MMF VF Filtrate
to C/T
Raw WW
(STP Effluent)
※ MDF : Micro Disk Filter
MMF : Multi-Media Filter
VF : Vortisand Filter
CF R O
Concentrate
To WWTP
Items Raw WW MDF MMF VF CF
CODMn(mg/l) 16∼28
Turbidity(NTU) 6.0∼14.0 5.5∼13.0 1.0∼4.0 1.0∼4.0 1.0∼4.0
E.coli(CFU/ml) 107,600 123,400
Steel Manufacture 6. Reference for Industrial WW Reuse
58 Membrane Filtration Process Hankyong National University
WW Filtrate
Concentrate(raw material fertilizer)
#1 RO Block
#3 RO Block
#2 RO Block
VMMF
Permeate
Concentrate
Items Raw WW Water Quality
P9026 P9019 Filtrate Concentrate
Q m3/day 1,440 1,920 - -
CODMn mg/L 100 40 <1 > 600
T-N Mg NH3/L 971 1,000 < 10 > 15,000
Conductivity uS /cm 7,000 7,000 < 20 > 100,000
Recovery % 93.1 6.9
Petro-chemistry 6. Reference for Industrial WW Reuse
59 Membrane Filtration Process Hankyong National University
Question and Answer
Dr. Chang-Han Yun
E-mail : [email protected]
Mobile : 010-288-2250
Contact ☞
60 Membrane Filtration Process Hankyong National University
Microporous
Hydrophobic
membrane
gas-filled pore
LIQUID
gas-liquid
interference
immobilized GAS
Pb
Membrane wall
Pgi
Pli
Ci
Cb
Pgas < Paq
MC Module
Feed Water
Degasfied Water
Sweep(N2)gas Vacuum
Membrane Contactor
Membrane Stripping Appendix – Membrane Contactor
61 Membrane Filtration Process Hankyong National University
Advantage of Membrane Contactor High contact area
No flooding
Independent control of each phase
Immiscible flow
<Example> Contact Area per Volume in Air Stripping
Data Equipment
ft2 / ft3 m2 / m3
Free Dispersion Columns 1 ∼ 10 3 ∼ 33
Packed / Trayed Columns 10 ∼ 100 33 ∼ 330
Agitated Columns 50 ∼ 150 164 ∼ 492
Membrane Contactors 500 ∼ 2,000 1,640 ∼ 6,562
Advantage Appendix – Membrane Contactor
62 Membrane Filtration Process Hankyong National University
Industrial Application of
Membrane Stripping and Membrane Absorption
Ultra pure water degassing (DO<10 ppb)
Process water deaeration
Boiler feed water degassing
Water decarbonation
Ammonia stripping/absorption
Culture media oxygenation
Application Field
of MS and MA Appendix – Membrane Contactor
63 Membrane Filtration Process Hankyong National University
Schematic Diagram of Facilitated Transport of Olefin
Olefin Olefin
Olefin
|
M+
M+
M+ = Complexing
Agent(Ag+)
Paraffin
Membrane
Appendix – Membrane Contactor