-
PART I INTRODUCTION
-
PART II INSTITUTIONAL AND REGULATORY FRAMEWORK
-
2.INSTITUTIONAL, POLICY, REGULATORY FRAMEWORK FOR RURAL SANITATION AND WASTEWATER MANAGEMENT
-
2.1 Overview
-
2.2.Institutional Arrangement
-
2.3.Policies and Regulations
-
2.4 Discharge Standards
-
2.5.Sources of funds
-
2.6.Typical provincial cases
-
2.7.Conclusions and recommendations
-
-
-
PART III TECHNICAL BASIS
-
3 Overview of Rural Sanitation and Wastewater Management
-
3.1 Domestic Wastewater
-
3.2 Rural Toilets in China – Source of Black Water
-
3.3 Decentralized vs. Centralized Rural Wastewater Management
-
-
4 Rural Wastewater Treatment Technology
-
4.1 Preliminary Treatment
-
4.2. Primary Treatment
-
4.3 Secondary Treatment
-
4.3.1 Attached Growth Process
-
4.3.2 Suspended growth Process
-
4.3.3 Waste Stabilization Pond
-
4.3.4 Constructed Wetlands
-
4.3.5 Subsurface Wastewater Infiltration Systems
-
-
-
5 Wastewater Treatment Process Design
-
5.1 General Design Consideration
-
5.2 Sewage Collection Alternatives
-
5.3 Wastewater Treatment Process Design
-
5.4 Water Reuse
-
5.5 Sludge Management
-
-
-
PART IV PROJECT PLANNING AND DESIGN
-
6 Project Planning and Design
-
6.1 Diagnosis for Project Villages – Initial Community Assessment
-
6.2 Establishment of Stakeholder Group
-
6.3 Assessment on Existing Conditions and Community’s Capacity
-
6.3.1 Physical Conditions Assessment
-
6.3.2 Community’s Capacity Assessment
-
-
6.4 Baseline Engineering Survey and Assessment
-
6.5 Project Feasibility Study and Environmental Impact Assessment
-
6.6 Selection of Operation Model
-
6.7 Project Cost Estimate
-
-
7 Community Participation
-
7.1 Why Need Community Participation?
-
7.2 Principles of Community Participation
-
7.3 Community Participation Activities
-
-
-
PART V PROJECT FINANCING
-
8 Financing, Subsidies, and Cost Recovery
-
8.1 Programmatic Costs
-
8.2 Project Implementation Costs
-
8.3 Project Financing
-
8.4 Subsidies
-
8.5 Cost Recovery
-
-
-
PART VI PROJECT IMPLEMENTATION AND MANAGEMENT
-
9 Procurement and Implementation
-
9.1 Procurement Principles
-
9.2 Procurement Alternatives
-
9.3 Procurement Planning
-
-
10 System Adminstration, Operation, Maintenance and Monitoring
-
10.1 Introduction
-
10.2 Management and Administration Arrangement
-
10.3 Operation and Maintenance
-
10.4 Reporting and Monitoring
-
10.5 Operator Training and Support
-
-
-
Appendix: Case Studies – Rural Wastewater Management in Zhejiang, Shanxi, and Jiangsu Province
-
1.Zhejiang Province
-
2.Shanxi Province
-
3.Jiangsu Province
-
4.Summary
-
-
REFERENCES
5.4 Water Reuse
- Categories: 5 Wastewater Treatment Process Design
- Time of issue: 2022-04-28 20:20:10
- Views: 0
To reduce dependence on freshwater and to maintain a constant source of irrigation water throughout the year, treated wastewater can be used as a reliable source of irrigation water to a wide variety of crops. Generally, only water that has received secondary treatment (i.e., physical and biological treatment) should be used, to limit the risk of crop contamination and the health risk to farmers and consumers. The treated water must comply with the Standard for Irrigation Water Quality (GB5084-2021)
There are two commonly employed irrigation techniques for the reuse of treated wastewater, including drip irrigation where the water is dripped slowly on or near the root zone of the plant, and surface water irrigation where water is routed overland in a series of dug channels or furrows. To minimize evaporation and contact with pathogens, spray irrigation is not recommended unless the water has received additional treatment (i.e., filtration and disinfection). Reusing properly treated water for crop irrigation can significantly reduce dependence on freshwater, and/or improve crop yields by supplying increased water and nutrients to plants.
Generally, surface and subsurface drip irrigation is the most appropriate irrigation method for reusing treated wastewater. The control and management of the water is easier and safer with a drip system and reduces the potential exposure of pathogens to the farmers.
Crops such as corn, alfalfa, fibers (cotton), tobacco, fruit trees, and foods requiring processing (sugar beet) can be grown safely with treated effluent. More care should be taken when growing fruits and vegetables, such as tomatoes, lettuce and others that could come into contact with the water or with crops where the root is consumed, such as carrots or potatoes. Energy crops like eucalyptus, poplar, willow, or ash trees can be grown in short-rotation and harvested for biofuel production. Since the trees are not for consumption, irrigation is a safe, efficient way of using treated effluent.
