Standardization of on-site treatment
in China

Dr. Meixue Chen
North Center for Rural Wastewater Treatment TechnologyResearch
Ministry of Housing and Urban-Rural Development, China
DEC. 2014

standards of on-site wastewater treatment

Domestic wastewater treatment rate in 2011year
100
90
80

town
township60village

Treatment rate %

70

50
40
30
20
100

Wastewater treatment ratio(%)

Up to the and of 2010, 22.9% of domestic wastewater from towns and villages

76543
2102008

2009

2010

2011

2012 Yearwastewater treatment ratio with 1% increasing every year

Situation••Diversity
Management– Who is responsible? Typically homeowner for
onsite，Inadequate methods of needs assessment– Standalization

Case study: Septic tankeffluent
Influent•Inexpensive•Simple to maintainthe firsttank

the secondtank

the thirdtank• Sludge may cause an odor problem• Not effective in removing nitrate andphosphorus and pathogenic organics• Potential pollution source ofgroundwater

Case study: Anaerobic Treatment

Anaerobictank

Water
recyclingtank

Fertilizer tank

• Low cost
• Energy use• Low removal rate
• Maintenance is necessary

Case study: Activated sludge

1m³,2m³,5m³,10m³,15m³/day• Flexible for decentralize wastewater treatment• Automatic control• Expensive for single family• management is relative complex

Case study: Constructed wetland
Plant

Water
distribution

Effluent
Waterbody

Grass

Wetland
Water-proof• constructed cost
• flexible land use
Small-scale decentralizedsystem• Low removal rate

0.2-5m3/d• Management

Case study: Leach Trenches
AA’

Ф75mm

Ф110mm
覆盖层细滤层

碎石(Ф10-30)

砾石(Ф5-10)精虑层

PVC 管粗虑层• Constucted and operation simple• Low cost
• pollution of groundwater• Poor quality of effluent

Case study: anaerobic tank+ ladder eco-filter
7
HRT:10-20min
6518

HRT:10-20min

293

10

HRT:20-30 min

411
HRT:30-60min

15 m3•d-1

12• Energy save
Unit：mg/L
item

COD

Influent

400

Effluent

60

BOD5NH4+-N

TN

TPSS

150

2540

4200

20

820

120

• Amonium and phosprous
removal• OdorCase study: Anearobic+ drop aeration + constructedwetland

高位
水箱

DN40

跌水挡
板

DN100

管道
外排

DN200
DN40
潜污泵DN100厌氧
池 tankAnaerobic

回流接触氧
化池
Oxic

人工湿地
ConstructedwetlandCase study: Bio- rotation + vegetable tank
3～10t/d，COD concentration is 100～100mg/L• Suitable in south area
• Vegetable management complex

Case study: Cluster system

Wasterwater

Discharge

ScreenBiofilter• Cluster system• High quality of effluent

Constructed wetland••

60m3/d，for 900 persons
floor area: 250m2

Decentralized wastewater systems
For COD removal

Aeration process
For nitrogen removal

Bio+Eco Treatment

Ecological toilet
Separation of fecal and urineStandard system of on-site wastewater treatment
Technique code for village rehabilitation (GB-50445-2008)
Technical specification of wastewater engineering for town andvillage (CJJ124-2008)
Technical Specification of wastewater treatment facilities for village(CJJ/T163-2011)
Complete equipment for domestic wastewater plant (CJ/T 355-2010)
Technical guide for rural domestic wastewater treatment in different
regions

Technical Specification of wastewater treatment
facilities for village(CJJ/T163-2011)

Main models of on‐site wastewater
treatment in China

Main contents
How to choose the suitable technology for rural area?
1 General provisions
2 Terms and symbols
3 General requirement
4 Treatment technologies

•
•••
•
•
•
•
•

Anaerobic biofilm tank
Biological contact oxidation tank
Biological aeration filter
Oxidation ditch
Rotating biological contactor
Activated‐sludge process
Ecological treatment of wastewater
Chemical phosphorus removal
Disinfection•••

Wastewater treatment station for COD removal
Wastewater treatment station for nitrogen removal
Wastewater treatment station for nitrogen and phosphorus removal

5 Wastewater treatment facilities in village
6 Wastewater treatment station in village

7 Construction and acceptance of engineering quality

主要内容Main contents
Discharged standard：

Items

Grade IA

Grade IB

Grade II Discharge

COD
T‐N
NH4‐N

50
155(8)

60
208(15)100‐
25(30)

T‐P

0.5

13 Reuse

Unit: mg/L

Technical guide for rural domestic wastewater
treatment in different regions

Environmental pressure factors

Town:
Average:5,420 capita/km2
Highest: Shanghai, Tianjin, Guangdong andFujian, range from10,000 to13,000
Lowest: Gansu, Qinghai, Xinjiang, range
from 2,000 to 3,000

Village:
Average:7,083/km2，lower than town；
Highest:Chongqing,25,000-33,000
Lowest: Qinghai, Gansu, 500-2,000

Population density of built-up area

Environmental pressure factors

Population density of built-up area

Town:
Average:5,420 capita/km2
Highest: Shanghai, Tianjin, Guangdong andFujian, range from10,000 to13,000
Lowest: Gansu, Qinghai, Xinjiang, range
from 2,000 to 3,000

Village:
Average:7,083/km2，lower than town；
Highest:Chongqing,25,000-33,000
Lowest: Qinghai, Gansu, 500-2,000

Town sewage treatment priority

 Spatial difference is apparent. But difference is indistinctive in thepriority regions between towns and villages;
 High in large area in Northern China, middle and downstream region ofYellow River.

Technical guide for rural domestic wastewater
treatment in different regions

东北华北
西北华南
西南中南

Technical guide for rural domestic wastewater
treatment in different regions

Wastewater in different regions
Domestic water use（L/P.day）
Types of village

NortheastNorth southNorthWest northWest southSouth

80‐13590～200100~14575～14080-160100～18040‐90

80～100

40~80

50～90

60-12060～120Normal economic ,simple toilet

40‐70

60～90

30~50

30～60

40-80

50～80

No flush toilet

20‐40

40～70

20~40

20～35

20-50

40～60

Good economic，bath ,flush
toilet ,wash mashine
Good economic, bath andkitchen

Charactics of wastewater（mg/L）
主要指标

COD

BOD5NH4+‐N

TP

100-400

50-3003-50

1.0-6.0

150-200

200-450200-300

20-90

2.0-6.5

6.5~8.5

100~200

70～300150~45020~50

1.5~6.0

6.5~8.0100~200

200~450200~300

20~90

2.0~6.5

West north

6.5～8.0150～200

150～400

100～150

20～50

South

6.5~8.5

100~200

100~300

60~15020~80West south
Northeast
North south
NorthpHSS

6.5~8.5

100-300

6.5-8.0

2.0～6.0
2.0~7.0

Technical guide for rural domestic wastewater
treatment in different regions
Northeast: septic tanks, anaerobic biofilter, bio‐contact oxidation tank, land
treatment, constructed wetlands, lagoon
North China : septic tanks, sewage digesters, aeration tank, sequencing batch bio‐reactor, oxidation ditch, biological contact oxidation , constructed wetlands, land
treatment
Northwest :septic tank, anaerobic digesters, anaerobic biofilter, constructedwetlands, land treatment..
Southwest: septic tanks, wetland, land treatment, anaerobic technology, bio‐contact oxidation tank, oxidation ditch, anaerobic biofilter
Middle south: septic tanks bio‐contact oxidation, oxidation ditch, constuctedwetland, lagoon, floating islands could be applied for sewage treatment.
southeast: septic tank, anaerobic biofilter, anaerobic digesters; biological contactoxidation tank, oxidation ditch, constructed wetlands, ecological filter.

• Complete equipment for domestic wastewater plant(CJ/T 355-2010)• Household sewage treatment plant (CJ/T 441-2013)

Main contents
10- 50 M3/day Facilities (CJ/T 355-2010)
Less than 2M3/day Facilities CJ/T 441-2013）• Discharge:Biofilm• Reuse：
MBRTechnologies

PG

1

Anaerobic +biofilm√——

2

Anoxic- oxic biofilm
Anaerobic digestion
Anoxic/ anaerobicbiofilm

√
——

——
√——

√34

Main contents

Challenges and futureChallenges and future

Reusing effluent for more sustainable
sewage treatment practices in Chinese
villages.
Supervision in sewage treatment facilities.
Appropriate regulatory authorities to beresponsible for daily testing of water
quality in sewage treatment facilities.
Suitable disinfection processes must beapplied in the rural sewage treatment
process.

Thanks for your attention!