Function of air compressor room in waterworks

Official note on the role of the water plant air compressor room

as the core supporting facilities of water treatment process, the air compressor room of waterworks undertakes the key function of providing compressed air power for the whole plant production system. Its function runs through the whole process of raw water treatment, water purification preparation, sludge disposal, etc. The specific functions and technical requirements are as follows:

1. core function positioning

1. process power source
   • provide air-water hybrid power for the filter backwashing system, remove suspended solids trapped on the surface of the filter material through the pulse air flushing process, and ensure the filtration accuracy of the filter (usually up to 0.5-5μm filtration accuracy)
   • drive dosing system metering pump to achieve precise dosing of flocculant, disinfectant and other chemicals (dosing error ≤ ± 2%)
   • supply gas to sludge dewatering equipment, and realize sludge transportation and pressure filtration operation through pneumatic diaphragm pump (water content can be reduced to 60-75%)
2. equipment protection barrier
   • provide positive pressure protection for key valves and instruments to prevent corrosion of electrical components caused by humid air intrusion (protection grade ≥ IP65)
   • drive the pneumatic actuator to complete the opening and closing of the pipeline valve to avoid the insulation failure of the electric device caused by the humid environment.
   • Provide blowback air source for online monitoring instrument to prevent contamination of sensor probe (blowback period can be adjusted to 5-30 minutes)

2. System Configuration Specification

1. equipment selection standard
   • main air compressor: the exhaust volume shall meet the demand of 120 of the maximum air consumption condition, and the variable frequency speed regulating device shall be equipped to realize 30-100% load regulation.
   • Standby unit: configured according to 50% of the capacity of the main equipment to ensure continuous operation of the system when a single unit fails.
   • Purification device: equipped with cold dryer (-20 ℃ pressure dew point) and precision filter (0.01μm filtration accuracy) to ensure the quality of compressed air
2. pipe network design requirements
   • the main gas supply pipe network adopts annular arrangement, the pipe diameter is designed according to the economic flow rate of 8-15 m/s, and the pressure loss is ≤ 0.1MPa.
   • Independent branch pipes are set at key gas points, equipped with pressure regulating valves and flow meters to achieve precise control.
   • Drainage system: 1 automatic drain valve shall be set for every 50 m pipeline, and the oil content of condensed water shall be ≤ 5mg/L.

3. Operation and Maintenance Specification

1. key points of daily inspection
   • check compressor discharge temperature (normal value 75-95 ℃), oil level (1/2-2/3 of observation window) and vibration value (≤ 5 mm/s)
   • check the dryer dew point indication (relative humidity ≤ 35% at -20 ℃) and filter pressure difference (alarm value 0.05MPa)
   • check the safety valve of the air tank (the setting pressure is 1.05-1.1 times the design pressure)
2. regular Maintenance Items
   • replace lubricating oil, oil filter and air filter every 2000 hours (three filter replacement cycle)
   • purge the pipe network every quarter to remove rust residue and condensed water in the pipe.
   • Entrust professional institutions to carry out pressure vessel inspection every year, and implement TSG 21 Safety Technical Supervision Regulation for Stationary Pressure Vessels

4. intelligent monitoring system

1. online monitoring platform
   • real-time acquisition of 12 operating parameters (pressure, temperature, flow, power, etc.), data update period ≤ 1 second
   • set three-level alarm threshold (warning value/alarm value/shutdown value) to realize early warning of failure
   • generate daily/monthly/annual operation report, including energy consumption analysis, equipment utilization and other key indicators
2. energy Efficiency Management Module
   • optimize compressor start-stop strategy through load curve to achieve more than 30% energy saving effect
   • monitor the specific power (kW/m & sup3;/min) and continuously optimize the system energy efficiency (level 1 energy efficiency ≤ 5.5kW/m & sup3;/min)

as the "respiratory center" of the production system, the stable operation of the air compressor room of the waterworks is directly related to the water quality and water supply safety. Enterprises should establish a complete equipment life cycle management system, combined with SCADA monitoring system and preventive maintenance strategy, to ensure that the air compressor room continues to provide high-quality, reliable compressed air power, to provide a solid guarantee for the safety of urban water supply.