The joint commissioning of sewage treatment plants is a key link in the construction process of sewage treatment plants. It is a comprehensive testing of the entire process system based on the preliminary acceptance of individual civil structures, equipment installation, electrical automation, pipeline valves, and the qualification of single machine commissioning. The purpose is to connect the process flow, inspect whether the equipment, automatic instruments, and pipelines, valves connecting various process units meet the design and usage requirements, assess the mechanical and electrical performance, instrument accuracy, and reliability of the automatic control system of the equipment under linkage conditions, ensure that the sewage treatment plant can be smoothly put into formal operation, and achieve the expected sewage treatment capacity and water quality standards. The following are the specific requirements for the joint commissioning of sewage treatment plants:
1、 Preparation before test drive
（1） Technical documentation preparation
1. Collect and organize complete design documents, including process flow diagrams, equipment installation drawings, electrical schematics, self-control logic diagrams, etc., to ensure that the personnel participating in the test run are familiar with the design requirements and process flow.
2. Develop a detailed linkage test plan, clarify the test steps, test content, test sequence, control indicators, safety measures, and emergency response plans, and organize relevant personnel for training and learning to ensure that each operator has a clear understanding of the test process and their own responsibilities.
3. Prepare the operation manual, maintenance manual, equipment list, spare parts list and other technical materials for the equipment, so as to facilitate the correct operation and maintenance of the equipment during the commissioning process, and timely handle equipment failures.
4. Develop various record forms, such as equipment operation parameter record form, water quality testing record form, fault and handling record form, etc., in order to accurately record various data and situations during the commissioning process.
（2） Equipment and facility inspection
1. Conduct a comprehensive inspection of all equipment, including the installation position, fixing condition, lubrication condition, and fastening degree of connection parts, to ensure that the equipment installation meets the design and specification requirements. Check the appearance of the equipment for damage, deformation, etc. If there are any problems, they should be repaired or replaced in a timely manner.
2. Check the installation quality of the pipeline system, including the direction, slope, connection method, valve installation position, and opening and closing status of the pipeline. Conduct pressure and tightness tests on pipelines to ensure that they are leak free, unobstructed, and meet process requirements.
3. Check whether the wiring of the electrical system is correct and firm, whether the grounding is reliable, and whether the electrical components such as switches, contactors, relays are sensitive and reliable in action. Perform insulation testing on electrical equipment to ensure that the insulation resistance meets the requirements.
4. Check whether the hardware equipment of the self-control system is installed properly and whether the software program is debugged normally. Calibrate and debug various instruments to ensure their measurement accuracy and reliability, and accurately reflect process parameters. Check whether the signal transmission between the self-control system and the equipment is normal, and achieve remote control and automatic adjustment functions.
5. Check whether the internal structure of each processing structure is intact, and whether there is leakage on the pool wall and bottom. Clean up debris and construction waste inside the structure to ensure cleanliness. Inspect the inlet and outlet, overflow outlet, and vent of each processing structure to ensure they are unobstructed.
（3） Material preparation
1. Prepare various chemical agents required for the test drive, such as coagulants, disinfectants, nutrients, etc., and ensure that the quality and quantity of the agents meet the requirements of the test drive. Establish a pharmaceutical management system to standardize the storage, retrieval, and use processes of pharmaceuticals.
2. Equip sufficient spare parts and vulnerable components, such as motor bearings, seals, belts, valve cores and seats, instrument sensors, transmitters, etc., so that they can be replaced in a timely manner in case of equipment failure, ensuring the continuity of the test run.
3. Prepare the necessary tools and equipment for the test drive, such as wrenches, screwdrivers, pliers, welding machines, cranes, testing instruments, etc., and ensure the integrity and availability of the tools and equipment.
4. Equip operators with necessary labor protection equipment, such as safety helmets, work clothes, gloves, protective shoes, goggles, etc., to ensure their personal safety.
（4） Personnel preparation
1. Establish a joint testing leadership group responsible for organizing, coordinating, and commanding the testing work. The group members should include relevant personnel from the construction unit, construction unit, supervision unit, design unit, and equipment supplier, and clarify the responsibilities and division of labor of each member.
2. Establish a trial operation team, and the operators should receive professional training, be familiar with sewage treatment processes and equipment operation procedures, master equipment maintenance knowledge and safety operating procedures. Operators must be assessed and qualified before they can take up their posts.
3. Equip professional technicians to provide technical guidance and problem-solving during the testing process. Technicians should have rich experience and professional knowledge in sewage treatment, and be able to promptly handle technical difficulties that arise during the commissioning process.
4. Organize all participants in the test drive to receive safety training, learn safety operating procedures and emergency response methods, and enhance their safety awareness and emergency response capabilities. Clear safety warning signs should be set up at the test site, and necessary firefighting and emergency rescue equipment should be equipped.
（5） Preparation for external conditions
1. Ensure that the external water pipelines and pump stations have the ability to transport sewage and can stably transport sewage to the sewage treatment plant. Coordinate with relevant departments on the source and delivery time of sewage to ensure sufficient sewage supply during the trial period.
2. Confirm that the external power supply capacity meets the load conditions for water supply and linkage trial operation. All main transformers and power supply equipment in the factory should be put into operation to basically meet the power load for linkage operation. Maintain close contact with the power supply department to ensure the stability and reliability of the power supply.
3. Coordinate the disposal channels of sludge to ensure that the sludge generated during the testing process can be properly treated. Sign an agreement with the sludge disposal unit to clarify the transportation, disposal methods, and costs of sludge.
2、 Test process requirements
（1） Equipment testing
1. Conduct single machine testing of the equipment one by one according to its automation level and operating sequence. Conduct a trial run of advanced pre-treatment equipment such as water pumps and grid machines to check whether the equipment's start, stop, speed regulation, frequency modulation, and other functions are normal, and whether there are any abnormal vibrations, noise, high temperatures, etc. during operation. Record and analyze various operating parameters of the equipment, such as motor current, voltage, speed, equipment flow rate, pressure, etc.
On the basis of passing the single machine test, carry out the linkage test of each processing unit equipment. According to the process flow, start the equipment of each processing unit in sequence, such as the sand settling tank, regulating tank, activated sludge aeration tank, sedimentation tank, disinfection tank, etc., and conduct joint testing to check the collaborative work ability and operational stability between the equipment. During the linkage testing process, it is important to check whether the interlocking control function of the equipment is normal, such as the interlocking between the grid machine and the belt conveyor, and the interlocking between the inlet pump and the liquid level control system.
3. Conduct joint testing of sludge treatment equipment, including sludge concentrator, sludge dewatering equipment, sludge conveying equipment, etc. Check the operation effect of the sludge treatment equipment, such as whether the moisture content, dewatering performance, and conveying capacity of the sludge meet the design requirements. At the same time, check the odor control and environmental hygiene during the sludge treatment process to ensure compliance with environmental protection requirements.
（2） Process trial run
1. Conduct process tests for each processing unit one by one according to the design scheme and process flow. Conduct aeration tests in the aeration tank, adjust the aeration amount and time, observe the growth and treatment effect of activated sludge, detect dissolved oxygen, sludge concentration, sludge settling ratio and other indicators to ensure that the aeration system can meet the needs of microbial growth and sewage treatment.
2. Conduct flocculant addition tests in the flocculation sedimentation unit, adjust the type, dosage, and method of flocculant addition, observe the flocculation sedimentation effect, detect suspended solids, chemical oxygen demand, and other indicators in the effluent, and determine the optimal flocculant addition parameters.
3. Conduct disinfectant addition tests in the disinfection unit, adjust the type, dosage, and contact time of the disinfectant, detect the total number of bacteria and Escherichia coli in the effluent, and ensure that the disinfection effect meets relevant national standards.
4. Conduct a full process linkage test of the entire sewage treatment process, starting from the inflow of sewage, passing through various treatment units, and finally discharging the effluent, to check the smoothness and treatment effect of the entire process flow. During the entire process of integrated testing, continuous monitoring of changes in water quality indicators such as chemical oxygen demand (COD), biochemical oxygen demand (BOD), suspended solids (SS), ammonia nitrogen (NH3-N), total phosphorus (TP), etc., and timely adjustment of process parameters based on monitoring results to ensure that the effluent quality meets the design discharge standards.
（3） Debugging of instruments and automatic control systems
1. During equipment and process testing, synchronize the debugging of instruments and automatic control systems. Check the measurement accuracy and reliability of various instruments, such as level gauges, flow meters, pressure gauges, dissolved oxygen meters, pH meters, etc., calibrate and verify the instruments to ensure that the measurement error of the instruments is within the allowable range.
2. Test the various functions of the self-control system, such as remote control, automatic adjustment, alarm interlocking, etc. Through the operation interface in the central control room, remote start, stop, speed control and other operations can be performed on the equipment to check its response and control accuracy. Set different process parameters and operating conditions, test the automatic adjustment function of the self-control system, and ensure that the equipment's operating status and process parameters can be automatically adjusted according to the actual situation.
3. Test the alarm interlocking function of the self-control system, simulate various abnormal situations such as equipment failure, liquid level exceeding or falling below the standard, water quality exceeding the standard, etc., check whether the self-control system can timely issue alarm signals and automatically take corresponding interlocking control measures, such as stopping equipment operation, starting backup equipment, opening overflow valves, etc., to ensure the safe operation of the sewage treatment plant.
（4） Water quality monitoring
1. Strengthen monitoring and analysis of water quality during the test drive process. Develop a detailed water quality monitoring plan in accordance with relevant national standards and specifications, specifying monitoring items, monitoring frequency, and monitoring methods. Regularly sample and analyze the inflow, effluent from each treatment unit, and final effluent to timely grasp the changes in water quality.
2. Equipped with professional water quality analysts and advanced water quality testing equipment to ensure the accuracy and reliability of water quality monitoring data. Carefully record and organize monitoring data, establish water quality monitoring archives, and provide a basis for subsequent process adjustments and operational management.
3. Adjust process parameters and equipment operation status in a timely manner based on water quality monitoring results. If it is found that the effluent quality of a certain treatment unit does not meet the standards, the reasons should be analyzed and corresponding measures should be taken for improvement, such as adjusting the aeration rate, increasing the dosage of flocculants, optimizing equipment operation time, etc., to ensure the stable operation of the entire sewage treatment process and the achievement of effluent quality standards.
3、 Test time and assessment criteria
（1） Test time
The joint commissioning time of sewage treatment plants is generally not less than 72 hours of continuous operation to fully test the stability and reliability of equipment and process systems. During the testing period, it is necessary to ensure that the equipment and process systems operate continuously to avoid any unplanned shutdowns that may affect the testing results. If a malfunction or abnormal situation occurs during the test drive, resulting in a parking time exceeding a certain limit, the test drive time should be recalculated or extended to ensure the integrity and effectiveness of the test drive.
（2） Assessment criteria
1. Equipment operation assessment: The equipment should run smoothly without any abnormal vibration, noise, or temperature rise. The various performance indicators of the equipment should meet the design requirements, such as flow rate, pressure, speed, power, etc. The failure rate of the equipment should be controlled within a certain range. During the trial period, the number of failures of the main equipment should not exceed [X] times, and the time for fault repair should not affect the normal progress of the trial.
2. Process operation assessment: The entire process flow should be smooth and unobstructed, and the connection between each processing unit should be reasonable and coordinated. The process system should be able to operate stably and meet the designed processing capacity and water quality standards. During the trial period, the inlet water quality should meet the water quality range required by the design, and the outlet water quality should meet the national or local discharge standards. The qualification rate of various water quality indicators should not be less than [X]%.
3. Assessment of Instruments and Automatic Control Systems: Instruments should measure accurately, display clearly, and have stable and reliable data transmission. The self-control system should be able to effectively control the equipment and process, and all control functions should be normal and sensitive, such as remote control, automatic adjustment, alarm interlocking, etc. During the testing period, the failure rate of instruments and automatic control systems should be controlled within a certain range to ensure the stable operation of the system.
4、 Safety and environmental requirements
（1） Safety requirements
1. Establish and improve safety management systems, develop detailed safety operating procedures and emergency plans. Set up clear safety warning signs at the test site to remind operators and other personnel to pay attention to safety.
2. Provide safety training to operators to familiarize them with safety operating procedures and emergency response methods, and master necessary safety knowledge and skills. Operators should wear labor protection equipment during the testing process, strictly follow safety operating procedures, and strictly prohibit illegal operations.
3. Strengthen the safety management of electrical equipment, mechanical equipment, lifting equipment, etc., conduct regular inspections and maintenance to ensure the safety performance of the equipment. During the operation of the equipment, it is strictly prohibited to carry out maintenance and upkeep work. If maintenance and upkeep are required, the machine must be stopped and corresponding safety measures must be taken.
4. Strictly manage special operations such as temporary electricity use, hot work, and high-altitude operations at the test site, obtain relevant work permits, implement safety protection measures, and ensure operational safety. Equip necessary fire-fighting and emergency rescue equipment at the test site, and regularly inspect and maintain them to ensure their integrity and effectiveness.
5. Strengthen safety inspections of the testing site, promptly identify and eliminate safety hazards. If a safety accident or safety hazard is discovered, immediate measures should be taken to deal with it and reported to the higher authorities in a timely manner.
（2） Environmental requirements
During the test drive process, it is necessary to strictly comply with national and local environmental laws and regulations, take effective environmental protection measures, and reduce pollution to the environment.
2. Properly treat and dispose of pollutants such as sewage, sludge, and exhaust gas generated during the test drive process. Wastewater should be treated to meet emission standards before being discharged, sludge should be dehydrated and disposed of according to regulations, and exhaust gas should be treated to meet emission standards before being discharged.
3. Strengthen the environmental hygiene management of the test site and keep it clean and tidy. Timely clean up the debris and garbage generated during the test drive process to avoid polluting the environment.
During the test drive process, it is necessary to strengthen the monitoring of the surrounding environment. If pollution or impact is found on the surrounding environment, immediate measures should be taken to rectify it and ensure the safety of the surrounding environment.
