1.0.1 This code was formulated with a view to making the wastewater engineering design in China implement the scientific outlook on development and comply with the national laws and regulations, and achieving the goals of prevention and control water pollution, enhancing and protecting environment, improving the health level of the people and ensuring the safety.
1.0.2 This code is applicable to the design of permanent outdoor wastewater engineering in the constructed, extended and renovated cities and towns, industrial areas and residential areas.
1.0.3 The design of wastewater engineering shall be mainly in accordance with the approved urban overall planning and wastewater engineering professional planning, shall be proceeded from the overall situation, and correctly handle the relation between industry and agriculture, urbanized areas and nonurbanized areas, short-term and long-term, concentration and dispersion, and discharge and utilization according to the planning age limit, engineering scale, economic benefit, social benefit and environmental benefit. Upon comprehensive verification, the design of wastewater engineering shall be able to accomplish environmental protection, economization of lands, advanced technology, economy and rationality, safety and reliability, and being suitable for local actual conditions.
1.0.4 The choice of the sewerage system (separate system and combined system) shall be determined according to the general planning of the urban, and combining the integrated consideration of the local landform characteristics, hydrological conditions, water body status, weather characteristics, former sewerage facilities, degree of the wastewater treatment, the water exit utilization and so on. Different districts in one city may adopt different sewerage systems. Except the arid districts with small rainfall amount, the newly built districts shall adopt the separate system. The existing combined waste water engineering system, if conditions permit, shall conduct the storm water and wastewater separating reconstruction according to the requirement of urban sewage planning; the one that does not have storm water and wastewater separating conditions temporarily, the combination measures of interception, adjustment and storage, and treatment shall be taken.
1.0.4A The storm water comprehensive management shall be carried out adopting the method of headwater reduction, process control and tail end treatment according to the concept of low impact development (LID), shall control the diffuse pollution, prevent and control the local flooding disaster and improve use the degree of storm water.
1.0.5 The design of waste water engineering system shall take comprehensive consideration of the following factors:
1 The recycling of the wastewater and the reasonable disposal of the sludge;
2 Coordination with the wastewater and sludge treatment and disposal system in the neighboring areas;
3 Coordination with the water supply system and flood drainage system in the neighboring areas and this area;
4 The probability of accepting the industrial wastewater and doing the centralized treatment and disposal;
5 Proper reconstruction of the former wastewater engineering facilities to fully play the efficiency of the engineering.
1.0.6 The water quality of the industrial wastewater drained into the urban waste water engineering system shall comply with the relevant standards, and shall not influence the normal operation of the urban sewerage pipe ditch and the wastewater treatment plants; it shall not harm the maintenance management personnel and shall not influence the reuse and safe discharging of the outgoing water after treatment or the treatment and disposal of the sludge.
1.0.7 The design of the wastewater engineering shall adopt the new technology, new process, new material and new equipment that are assayed and tried to be effective on the basis of continually summing up the experience in scientific research and production practice.
1.0.8 The wastewater engineering should adopt the mechanized and automated equipment, and the one with heavy operation, influence on safety and health hazard shall adopt the mechanized and automated equipment.
1.0.9 The design of wastewater engineering not only shall comply with this code, but also shall meet the relevant current standards and codes of the nation.
1.0.10 In the earthquake, collapsible loess, expansive soil and permafrost areas and the other special areas. The design of wastewater engineering shall also meet the requirements of the current relevant special codes.
1 General Provisions
2 Terms and Symbols
2.1 Terms
2.2 Symbols
3 Designed Flow Amount and Water Quality
3.1 Domestic Sewerage Amount and Industrial Wastewater Amount
3.2 Storm Water Amount
3.3 Combined Water Amount
3.4 Designed Water Quality
4 Sewerage Pipe Ditch and Ancillary Structures
4.1 General Requirements
4.2 Hydraulic Calculation
4.3 Pipe
4.4 Inspection Well
4.5 Drop Well
4.6 Water Seal Well
4.7 Storm Water Inlet
4.8 Intercepting Well
4.9 Water Outlet
4.10 Drainage of Interchange
4.11 Inverted Siphon
4.12 Ditch
4.13 Pipe Integration
4.14 Strom Water Storage Tank
4.15 Storm Water Infiltration Facilities
5 Pumping Stations
5.1 General Requirements
5.2 Designed Flow Amount and Designed Head
5.3 Collecting Tank
5.4 Design of Pump House
5.5 Outlet Water Facilities
6 Wastewater Treatment
6.1 Site Selection and General Layout
6.2 General Requirements
6.3 Bar Screen
6.4 Grit Chamber
6.5 Settling tank
6.6 Activated Sludge Process
6.7 Chemical Phosphorus Removal
6.8 Oxygen Supply Facilities
6.9 Biofilm Process
6.10 Returned Sludge and Excess Activated Sludge
6.11 Natural Treatment of Wastewater
6.12 Advanced Wastewater Treatment and Recycling
6.13 Sterilization
7 Sludge Treatment and Disposal
7.1 General Requirements
7.2 Sludge Thickening
7.3 Sludge Digestion
7.4 Mechanical Sludge Dewatering
7.5 Sludge Delivery
7.6 Sludge Drying and Incineration
7.7 Sludge Integrated Application
8 Inspection and Control
8.1 General Requirements
8.2 Inspection
8.3 Control
8.4 Computer Control and Management System
Appendix A Method of Establishing Rainfall Intensity Formula
Appendix B Minimum Clearance of Sewerage Pipes and Other Underground Pipelines (Structures)
Explanation of Wording in This Code