Can air compressor be used for aeration and agitation?

Explanation on the application of air compressor in aeration agitation

As a universal air source equipment, air compressors have widespread application feasibility in aeration and mixing processes. After technical analysis and industry practice verification, its applicability, system configuration and operation management points are explained as follows:

1. Technical feasibility analysis

1. Core function adaptation
   • Aeration and agitation need to meet the air-water ratio of 0.5-1.5m³/(min·m³), and the air compressor can provide a continuous and stable air supply.
   • Typical working conditions: A 15kW air compressor is required to treat 100m³/h sewage, and the exhaust volume is ≥2.5m³/min.
2. pressure matching
   • The aeration tank with a water depth of 3-5 meters requires an air supply pressure of 0.05-0.08MPa, which can be met by conventional air compressors.
   • Deepwater aeration (>8 meters) requires a two-stage compression system to ensure that the end pressure is ≥0.12MPa.

2. System configuration requirements

1. Air source purification device
   • Equipped with a freezing dryer (pressure dew point of-20℃) to avoid clogging of the aerator caused by condensed water.
   • Install a 5μm primary filter + a 1 μ m precision filter to ensure that the cleanliness of the compressed air meets the ISO 8573-1:2010 Class 2 standard.
2. Aerator selection
   • Microporous aerator: Oxygen utilization rate is 15-25%, suitable for municipal sewage treatment.
   • Jet aerator: oxygenating capacity of 3-5kgO ˇ/kWh, suitable for industrial wastewater treatment.
3. Pipeline system design
   • The main gas supply pipe diameter is designed according to an economic flow rate of 8-15m/s, and the pressure loss is ≤0.02MPa/100m.
   • The branch pipes are equipped with regulating valves and flow meters to achieve accurate air control in each aeration unit.

3. Energy efficiency optimization plan

1. Frequency conversion control technology
   • Adjust the gas supply amount in real time according to the dissolved oxygen concentration (DO value), and the energy saving rate can reach 20-35%.
   • Typical case: When the DO value is reduced from 4mg/L to 2mg/L, the gas supply volume is reduced by 40%.
2. heat energy recovery system
   • Equipped with a waste heat recovery device, hot water of 50-70℃ can be obtained to meet the insulation needs of the aeration tank.
   • The heat recovery efficiency reaches 70-85%, and the annual standard coal saving is about 15 tons (taking the 110kW unit as an example).

4. Operation and maintenance specifications

1. daily monitoring
   • Check the aerator resistance (normal value ≤0.03MPa), and clean it if it exceeds 0.05MPa.
   • Monitor the oil content of compressed air (≤0.1mg/m³) to avoid oil pollution clogging the aeration holes.
2. regular maintenance
   • Replace the air filter element every 2000 hours and clean the cooling system.
   • Calibrate pressure gauges and safety valves every year and implement TSG21 “Safety Technical Supervision Regulations for Fixed Pressure Vessels”.

5. Typical application scenarios

1. municipal sewage treatment
   • An air compressor + microporous aeration system is used to achieve a BOD removal rate of>90%.
   • It is equipped with an intelligent control system to automatically adjust the gas supply amount according to the amount of water entering.
2. industrial wastewater treatment
   • Equipped with corrosion-resistant pipelines (316L stainless steel) to adapt to harsh working conditions with pH 2-12.
   • Jet aeration is used to improve the removal efficiency of refractory organic matters.

6. Selection decision-making suggestions

1. Process adaptability
   • Activated sludge method: Frequency conversion air compressors are preferred to match the biological reaction kinetics.
   • SBR process: A rapid start-stop unit needs to be configured to meet the needs of intermittent aeration.
2. quality assurance system
   • Select explosion-proof models with CE certification and are suitable for anaerobic environments with methane concentration>25%.
   • Equipped with an online oxygen monitor to achieve closed-loop control of dissolved oxygen concentration and gas supply volume.

Air compressors have significant technical advantages and economy in the aeration and mixing process. Through reasonable system configuration and operation management, the dual goals of efficient oxygenation and energy conservation and consumption reduction can be achieved. Enterprises should establish a full life cycle management system, formulate personalized solutions based on water quality characteristics and process requirements, and recommend configuring standby units and intelligent monitoring platforms for high-load conditions to ensure the continuous and stable operation of the aeration system and provide reliable water treatment processes. Gas source guarantee.