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What is MBR ?Combined Technology of Activated Sludge Process and Membrane Separation Process

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MBR Enables High Quality Treated Water, Smaller Footprint & Simple system

<MBR System>

Excess SludgeDeni Nitri

Recycle

Influent ScreenGC

Effluent

Influent

Excess Sludge

<Conventional System>

Sedimentation

Nitri

RAS

Recycle

SF UVDeniScreenGC

Primary Clarifier

Effluent

FineScreen

Comparison with Conventional System

What is MBR?What is MBR?

MLSS: 10000-15000ppm

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Schematic Diagram of MBRCoarse Screen

Balancing Tank

Denitrification Tank

Nitrification Tank

Sludge Storage Tank

Membrane Unit

Fine Screen

Disinfection Tank

Feed Pump

Grit Chamber

Blower

What is MBR?What is MBR?

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Attractive for limited land projects:•Retrofits (increased capacity and/or stricter consent) •Decentralised or Industrial

Comparison of FootprintWhat is MBR?What is MBR?

MBR Conventional

5,600 m3/d, 0.7 ha 6,000 m3/d, 4.5 ha

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Membrane Cartridge

Chlorinated polyethylene

Micro FiltrationPore size : 0.4μm0.5m×1.0m0.8m2/Cartridge

Nozzle

Membrane PanelSpacer

Membrane Sheet

Micro scope

Introduction of typical SMUIntroduction of typical SMU

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Manifold

Membrane case

Tube

Membrane cartridge

Diffuser case

Diffuser

Structure of typical SMUIntroduction of typical SMUIntroduction of typical SMU

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Features of Typical MBR

① Simple system – Less equipment② Energy saving③ Easy operation④ Long Lifetime⑤ World’s market leader

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Membrane Unit

BlowerPermeate tank

M

No backwash pump

No permeate pump

No chemical cleaning tank

Simple piping design

Membrane tank

Sodium HypochloriteDosing Tank

Simple System – Less Equipment -Features of typical MBRFeatures of typical MBR

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Filtration at low pressure is possible.(Typical pressure: 5 – 10 kPa)

Small water head is applicable to collect permeate.

Suction pump is not required. Typical gravity

filtration

Water Head

Simple System – Gravity Filtration -Features of typical MBRFeatures of typical MBR

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■ Cleaning Timing

･ Periodically （ 3 ～ 6 month ） ･ Increase of Trans-membrane Pressure (TMP)

■ Chemical

･ Sodium hypochlorite （ 0.5% ） for organic fouling ･ Oxalic acid （ 1.0% ） for inorganic fouling

■ Chemical Volume : 3L/cartridge ■ Cleaning Duration

Pouring 5min. ＋ cleaning 60 ～120min.

Clean membranes in aeration tanks !

MBR Tank PermeateTank

ChemicalDosing Tank

M

Simple System – In Situ Cleaning -Features of typical MBRFeatures of typical MBR

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Aeration plays two roles forenergy conservation !

1. Membrane Scouring Coarse bubble aeration under

the membrane enables the

membrane surface clean

2. Oxygen supply for biomass This air is also used to transfer

the oxygen into the biomass

Upward airflow among membranes

Energy Saving – Membrane Aeration -Features of typical MBRFeatures of typical MBR

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4% failure in 10 years!% of Membranes Replaced

Age Year

# of PanelUsed inStudy

FailuresExcludingRepairs

Annual %ExcludingRepairs

Cumulative %

ExcludingRepairs

Annual %IncludingRepairs

Cumulative %

IncludingRepairs

1 175796 0 0 0.00 0.00 0.00

2 152696 394 0.26 0.26 0.27 0.27

3 112221 530 0.47 0.73 0.58 0.85

4 79386 669 0.84 1.57 0.91 1.76

5 64486 1388 2.15 3.73 2.34 4.10

6 35636 33 0.09 3.82 0.32 4.42

7 15386 55 0.36 4.18 0.36 4.78

8 4286 20 0.47 4.64 0.47 5.25

9 686 0 0 4.64 0.00 5.25

10 386 0 0 4.64 0.00 5.25

Long LifetimeFeatures of typical MBRFeatures of typical MBR

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Influent Effluent

BOD 312 ＜ 10

SS 228 ＜ 10

NH4-N 35 ＜ 1

NO3-N － ＜ 8

T-N 50 ＜ 10

F.colifoms

－ ＜ 2.2 c/100mL

Turbidity － ＜ 2NTU

Peak 　 78,000m3/d ：Flux=0.80m3/m2/d

Ave. 55,000m3/d ：Flux=0.56m3/m2/d<Design water quality>

<Design flow rate>

Design Parameters ofReference PlantsReference Plants

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PumpStation

Equalization Tank(4.6hrs)

Fine Screen(1mm bar)

AnoxicTank(3.0hrs)

AerobicTank(3.0hrs)

Coagulant BlowerSodiumHypochlorite

Permeate

RAS(2Q)

ExcessSludge

MembraneUnit

Reuse

System Flow of STPReference PlantsReference Plants

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