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PART I INTRODUCTION
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PART II INSTITUTIONAL AND REGULATORY FRAMEWORK
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2.INSTITUTIONAL, POLICY, REGULATORY FRAMEWORK FOR RURAL SANITATION AND WASTEWATER MANAGEMENT
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2.1 Overview
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2.2.Institutional Arrangement
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2.3.Policies and Regulations
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2.4 Discharge Standards
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2.5.Sources of funds
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2.6.Typical provincial cases
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2.7.Conclusions and recommendations
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PART III TECHNICAL BASIS
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3 Overview of Rural Sanitation and Wastewater Management
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3.1 Domestic Wastewater
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3.2 Rural Toilets in China – Source of Black Water
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3.3 Decentralized vs. Centralized Rural Wastewater Management
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4 Rural Wastewater Treatment Technology
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4.1 Preliminary Treatment
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4.2. Primary Treatment
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4.3 Secondary Treatment
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4.3.1 Attached Growth Process
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4.3.2 Suspended growth Process
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4.3.3 Waste Stabilization Pond
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4.3.4 Constructed Wetlands
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4.3.5 Subsurface Wastewater Infiltration Systems
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5 Wastewater Treatment Process Design
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5.1 General Design Consideration
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5.2 Sewage Collection Alternatives
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5.3 Wastewater Treatment Process Design
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5.4 Water Reuse
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5.5 Sludge Management
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PART IV PROJECT PLANNING AND DESIGN
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6 Project Planning and Design
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6.1 Diagnosis for Project Villages – Initial Community Assessment
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6.2 Establishment of Stakeholder Group
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6.3 Assessment on Existing Conditions and Community’s Capacity
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6.3.1 Physical Conditions Assessment
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6.3.2 Community’s Capacity Assessment
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6.4 Baseline Engineering Survey and Assessment
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6.5 Project Feasibility Study and Environmental Impact Assessment
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6.6 Selection of Operation Model
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6.7 Project Cost Estimate
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7 Community Participation
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7.1 Why Need Community Participation?
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7.2 Principles of Community Participation
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7.3 Community Participation Activities
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PART V PROJECT FINANCING
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8 Financing, Subsidies, and Cost Recovery
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8.1 Programmatic Costs
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8.2 Project Implementation Costs
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8.3 Project Financing
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8.4 Subsidies
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8.5 Cost Recovery
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PART VI PROJECT IMPLEMENTATION AND MANAGEMENT
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9 Procurement and Implementation
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9.1 Procurement Principles
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9.2 Procurement Alternatives
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9.3 Procurement Planning
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10 System Adminstration, Operation, Maintenance and Monitoring
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10.1 Introduction
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10.2 Management and Administration Arrangement
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10.3 Operation and Maintenance
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10.4 Reporting and Monitoring
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10.5 Operator Training and Support
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Appendix: Case Studies – Rural Wastewater Management in Zhejiang, Shanxi, and Jiangsu Province
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1.Zhejiang Province
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2.Shanxi Province
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3.Jiangsu Province
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4.Summary
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REFERENCES
5.1.1 Decentralized vs. Centralized
- Categories: 5.1 General Design Consideration
- Time of issue: 2022-04-28 18:34:13
- Views: 0
As introduced in Section 3.3, wastewater treatment systems are categorized into decentralized and centralized systems. Both alternatives will be assessed, based on the amount of wastewater, effluent discharge standards, as well as local physical and economic conditions. Considering the rapid expansion of urban area, some villages may be located only 3-5km away from urban municipal wastewater treatment plants. Under this circumstance, construction of a sewage system to collect and convey the rural wastewater to existing municipal wastewater treatment plants would be recommended.
In China, many villages are composed of different small but densely populated neighborhoods that are separated by agricultural fields or topographic features, such as hills, streams, rivers, highways, or other physical features. In these situations, it may be more feasible to install decentralized systems to serve each neighborhood or cluster of houses instead of installing a large, complex, and expensive collection system. Table 5.1 provides summaries on the different scenarios for the application of decentralized and centralized systems.
Table 5.1 Applicability of Decentralized and Centralized Systems
Factor |
Decentralized System |
Centralized System |
Population density |
Low density |
High density |
Topography |
Complex |
Relatively flat, or suitable for gravity flow |
Water consumption |
Medium to low consumption |
High consumption |
Estimated volume of wastewater |
Suitable for low volume of wastewater (e.g., less than 50 m3 per day) |
Suitable for large volume of wastewater (e.g., over 50 m3 per day) |
Capital cost |
Relatively low investment on small-scale equipment procurement and installation |
Heavy investment on sewer system construction |
Operation requirement |
Depends on the technologies applied: (i) for passive processes, little intervention is needed; (ii) for advanced technologies, qualified professionals are required. |
Need qualified professionals to operate. |