Wastewater Production, Treatment, and Use in China Keqiang ZHANG Professor, Ph.D tutor, Division Director Agro-Environmental Protection Institute, MOA (AEPI) March 2013
Outline Wastewater production and treatment Wastewater use and disposal Regulations/implementation of national guidelines Future challenges Current approach of the government related to
wastewater management Possible solutions to make use of wastewater safer and productive
Water affairs in our life Rainfall
River
City
Tap-water plant
Sewage treatment plant
Receiving water body
Sewage pipe network
Groundwater Rural water utilization
Municipal and industrial water utilization
Sewage source Household •
Domestic sewage
Public place Hospital (in disinfection and pre-treatment)
•
Industrial sewage (in pretreatment discharge up to the standard)
•
Industrial wastewater
•
Initial rainwater (uncollected)
Wastewater production and treatment Production Industrial source: 73.833 billion m3/year Municipal source: 34.330 billion m3/year (1st National Pollutant Source Census Bulletin, 2010)
Fashion poison
Textile industrial wastewater discharge, Greenpeace, 2012
habitat or tomb?
Municipal wastewater drainage, Greenpeace, 2007
Discharge and Treatment of Wastewater 1．Total Discharge of Wastewater（billion ton）
61.73
Among：Industrial Wastewater Discharge
23.75
37.98
Urban Sewage Discharge
2．total COD Discharge（million ton）
12.38
Among：Industrial COD Discharge
4.35
Urban Living COD Emission
8.03
3．Total Ammonia Nitrogen Emissions（million ton）
1.20
Among：Industrial Ammonia Emissions
0.27
Urban Domestic Ammonia emissions
0.93
4．Industrial Wastewater Standard-Reaching Discharge Rate （%）
95.3
5．Recycling Rate of Industrial Wastewater（%）
85.7
6．Treatment Rate of Urban Sewage（%）
82.3
7．Treatment Rate of Urban Domestic Wastewater （%）
72.9
From 2010 Environment Bulletin
Treatment
Physical, chemical, biological ways
Regular approaches
Bio-chemical approaches Physical-chemical processes
Media filtration
Advanced measures
Bio-film adsorption Photo-catalytic oxidation
Chlorination
Disinfection
Ultraviolet Ozone
A/0, 5.50% SBR, 14.70% A/A/O, 16.80%
BAF, 4.30% Physicochemical+ biochemistry,
activated sludge process, 17.90%
1.90%
secondary treatment, biochemical 1.20% Oxidation ditch, 33.10% others, 4.60%
from the statistical data on national sewage treatment facility put into service by 2009.
Wastewater Treatment Equipment
Wastewater use and/or disposal The history, including 3 stages, of wastewater irrigation in China began in 1956, and the wastewater irrigating facilities were built since 1957. I 1956-1965 ： Wastewater irrigation could increase water and fertilizer resource, and this irrigating method should be Vigorously promoted; II 1965-1975 ： People start to doubt the pollutions from wastewater irrigation, but the area was still Extending. III 1975-about 1998： Wastewater irrigation had a violent development. The area were Increased to 3.618 million ha in1998.
Sewage recycling Sewage
Municipal sewage treatment plant
Groundwater irrigation
Urban recycling water plant
Agriculture landscape Industry
Municipal administration and gardening
Life
The wastewater irrigation area are mainly distributed in the Yellow river basin, the Liao river basin, the Hai river basin and the Huai river basin, accounted for above 90%. There are 5 relatively large wastewater irrigation areas in China, and that is Beijing, Tianjin, Shenyang and Fushun, Shanxi and Xinjiang Shihezi. Xinjiang Shihezi
Beijing
Shenyang/Fushun
Tianjin Shanxi
Harms from wastewater irrigation To soil: The physicochemical properties change of soil, such as Soil compaction, worse soil permeability, and secondary soil salinization and sodification. secondly serious organic matter and heavy metal pollution. To crops: Heavy metal content exceed the standard, yields and quality decline. The crops yields of Shenyang and Fushun wastewater irrigation area were reduced by 11,250-22,500kg/hm2 in recent years, compared to contrast area. To ground water: The major pollutants exceed the standard were total hardness, nitride, sulfate, total bacteria and e. coli.
Resource: China's Farmland Sewage Irrigation Development and Its Impact on Crop Research by Huang Chunguo.
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Regulations and implementation of guidelines Official regulation Technology and Policy of Municipal Sewage Treatment and Pollution Prevention and Control —Ministry of Environmental Protection (MEP), 2000 Covered: environmental protection, resource conservation and recycling, industrial sustainable development, biological and ecological security and healthy, etc.
National guidelines Guideline of Urban Sewage Treatment and Pollution Prevention and Control Technology —Ministry of Environmental Protection (MEP), 2001 The Urban Sewage Recycling Technology Guide —General Administration of Quality Supervision, Inspection and Quarantine (AQSIQ), 2012
National Standards Standards for Irrigation Water Quality (GB 5084-92) The Reuse of Urban Recycling Water-Water Quality
Standard for Scenic Environment Use (GB/T18921-2002) The Reuse of Urban Recycling Water-Water Quality
Standard for Industrial Uses (GB/T 19923-2005) The Reuse of Urban Recycling Water-Quality of Farmland
Irrigation Water (GB 20922-2007) Technology Code for Municipal Wastewater Reuse in
Agriculture (GB/T 22103-2008) ……
Implementation of guidelines Available management on the water resource (Zhejiang province, Baidu)
Publicity Poster (MWR, 2010)
Publications
Challenges In Technical Save the electricity and heat energy & Lower the consumption GHG reduction during the course of wastewater treatment Available approach about sludge treatment and recycling Where is the reclaimed wastewater going?
In policy Support of advanced technologies and processes in the sludge
treatment and recycling Improvement of market adjustment mechanism
In administration Reinforcement of monitoring and management power Feasible implementation of corresponding regulations
Energy consumption status analysis of the sewage treatment E.g.: Specific power consumption distribution in the municipal sewage treatment plant (Dongfang LIU, 2010) Power consumption in some plants Scale (104 t)
Grade
Consumption (kW.h)
1.2
2
0.218
2
2
0.232
4.5-5
2
0.335
1.4
2
0.255
Note
Without Anaerobic digestion
With digestion
Power consumption from the sewage treatment accounts for 50%-80% of the total amount while the sludge treatment only accounts for 15%-40%. Sewage treatment is the key for the energy conservation.
Energy consumption analysis of treatment process Analysis of sewage treatment/energy consumption pollution The energy consumption for 1.0kg BOD elimination is 0.5kW.h. Pollutants emission from our national power plants is nearly to 7.23kg/kW.h. 1.0kg BOD elimination will induce to 3.61kg pollutants emission (1.2kg wastewater and 0.37kg sludge) Sewage treatment is the industry with high consumption and high contamination.
(Dongfang LIU, 2010)
Government’s approach to wastewater management Focal point transformation Sewage treatment pond
Producing source
Requirement for the sludge disposal and treatment will be gradually raised. Pertinent policy and criteria are going to be improved in light of the aim “energy conservation and emission reduction”. E.g.: Environmental/ecological/green taxation set-up
Possible solutions Since about 2000, the government of China did not promote Wastewater irrigation on farmland. However state and local governments still support some research projects on reclaimed water irrigation (basically meet Standards for Irrigation Water Quality (GB 5084-2005) )
Thank you for your attention
