Demonstration of suburban sewage pre-concentration by enhanced membrane 

coagulation reactor (E-MCR) for organic matter recovery: a pilot study

Zhengyu Jin, Hui Gong, Kaijun WangSchool of EnvironmentTsinghua University

Trends of wastewater treatment

2000s~~1900s 1914 1950s~ Future

Public sanitation

Preventing eutrophication 

Activated sludge Dealing with water scarcity

Preventing diseases

Organics removal N, P removal Water 

reclamation

Current demands of wastewater treatment

WWTP in Strass, Austria

100%Energy self-sufficiency

NEWater in Singapore

Energy conservation

High water quality 

High quality

Sewage

A/O MF RO UV

NEWater

AB processSewage Effluent

Anaerobic DigestionDEMON

Resource recovery from WWTPs 

Factory

Water

Energy

Nutrients

High quality water

Maximizing energy recovery

Minimized carbon emission

Maximizing nutrients reuse

Minimized costs

Minimized footprint

NEWater

Strass

Source separation in maximizing recovery

Decentralized Ecological Sanitation (G. Zeeman,2008)

Too advanced for China!

Moderate step forward in China

• Shortened transportation;• Without much change of 

original drainage system;• More resource conservation;• Less footprint.

Centralized WWTPs

Decentra-lized

WWTPs

Decentra-lized

WWTPs

Decentra-lized

WWTPs

• Distant transportation;• Huge collection system；• Resource missing;• WWTPs with Big footprint;

Conventional centralized wastewater treatment system

Decentralized wastewater treatment system

Our plan

Key Issues

Consideration StrategyBalance of efficiency and 

costs Microfiltration/Ultrafiltration

Transfer but not transform Limited aeration and chemicals use

Fouling Unpreventable then make use of it! (Dynamic cake layer)

Recovery improvement and less consumption

Proper operation optimization

Steps for application Pilot test with commercial module

Our sets for pilot test

Membrane：PVC reinforced hollow fibre(1/4 commercial module)Working area：24m2

Working volume：280LAverage pore size：0.02µm

Outline of the UF E-MCR concentration system

Raw sewage

Membranemodule

Influent pump

Dosage pump

PACl

Air compressor

PressureGauge

Valve

Concentrate

Pressuresensor

Metal tuberotameter

Permeatepump

Permeate

Recorder

Solenoidvalve

Time Delay Relay

PAC

Dosage pump

Mixing tank

Ejector

Solenoidvalve

PolyaluminiumChloride

PowderedActivatedCarbon

Working Senarios

Scenarios Dosage Fouling control

Initial Flux

(L/m2h)

Relaxation ratio

(min:min)

AB pressure/

IA rate

AB ratio

/IA ratioCRT (d)

I / None 5 5:1 / / /II PACl 60mg/L IA 5 5:1 0.5 m3/m2h 1min:5min /

IIIPACl 

60mg/L+ PAC 40mg/L

IA 5 5:1 0.5 m3/m2h 1min:5min /

IVPACl 

60mg/L+ PAC 40mg/L

AB 5 5:1 50 kPa 30s:5min30s 5

VPACl 

60mg/L+ PAC 40mg/L

AB 10 5:1 50 kPa 30s:5min30s 5

VIPACl 

30mg/L+ PAC 20mg/L

AB 20 5:1 100 kPa 30s:5min30s 2.5

IA: Intermittent aerationAB: air backflushingCRT: concentrate retention time

Filtration performance

1

10

100

1000

0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400

Perm

eabi

lity 

(L/m

2 h∙b

ar)

Duration (h)

I II III IV V V

DF: Direct filtration; CCP: Common coagulation process; ECP: Enhanced coagulation process

DFCCP+IA

ECP+IA

ECP + AB ECP + AB ECP + AB

⁄

• ECP alleviates fouling rate• AB achieves long‐term pseudo‐steady operation

Retention Performance

0

100

200

300

400

500

600

700

800

900

1000

0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400

CO

D c

once

ntra

tion 

(mg/

L)

Duration (h)

Influent Permeate

I II III IV V V

DFCCP+IA

ECP+IA

ECP + AB ECP + AB ECP + AB

50%

60%

70%

80%

90%

100%

原水 PACl 30mg/L PACl 30mg/L+PAC 30mg/L

>0.45μm 0.22μm~0.45μm 100kDa~0.22μm 1kDa~100kDa <1kDa

Raw sewage

30%15%

Enhanced coagulation process effects on retention

Concentration performance

0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400

Duration (h)

I II III IV V V

DFCCP+IA

ECP+IA

ECP + AB ECP + AB ECP + AB

Moderate concentration approaches steady state

1900 2000 2100 2200 2300 2400Duration (h)

Influent TP Permeate TP

P & N removal

0

10

20

30

40

50

1800 1900 2000 2100 2200 2300 2400

Con

cent

ratio

n (m

g/L)

Influent TN Permeate TNInfluent NH4-N Permeate NH4-N

Energy consumptionPilot‐scale E‐MCR

y Requirement entrate, m3/d 7.83H2O 4nergy, kWh/m3 ‐0.011nfluent tube, m H2O 0.2mping energy, kWh/m3 ‐0.0006meate extractionm H2O 4.68rate, m3/d 7.83

mping energy, kWh/m3 ‐0.013d pumping energy, kWh/m3 ‐0.0246backflushingbrane air blowing depth, m H2O 1.0ow rate, m3/h 0.135compressor energy, kWh/m3 ‐0.012nsumption, kWh/m3 ‐0.0366y Production Potentialnt COD, mg/L 278.1ency, % 90egradability, % 60.0uction, mol/m3 influent 2.34

d i f h

90,0%

8,2% 1,7%

COD mass balance for scenario VI

Concentrate

Permeate

Mineralized

SOUR(mg O2/g VSS∙h)

7 8 13 18 29

Mineralization(%) 1 2 4 11 32

SOUR of the concentrate: 4.37 mgO2/gVSS∙h

Take home

ong‐term pilot‐scale continuous membrane‐ased sewage pre‐concentration is achieved

Dynamic cake layer functions in pseudo‐steady peration

High carbon recovery led by “transferring” and limited transforming”Optimization remains and Larger‐scale (100m2) s on…

THANKS FOR YOUR ATTENTION!