How to deal with water in compressed air of air compressor

Technical specification for water-containing treatment of compressed air for air compressors

In order to standardize the operation and management of compressed air systems and clarify the technical requirements for water-containing treatment, the source, impact and treatment plan of moisture in air compressor exhaust are now explained as follows:

1. Water sources and impacts

1. moisture source

The moisture in compressed air mainly comes from water vapor in the ambient air. During the compression process of the air compressor, the air temperature increases and the water vapor saturation increases; when the compressed air cools, the water vapor condenses to form liquid water, which enters the pipeline system with the compressed air.

2. moisture

• equipment corrosion: Moisture mixes with impurities (such as oil and particulate matter) in the compressed air to form acidic condensate that corrodes pipelines, valves and gas-using equipment.
• process risk: In spraying, food packaging and other processes, moisture may cause product surface defects or the growth of microorganisms.
• increased energy consumption: Water accumulation in the pipeline causes pressure loss, and the air compressor requires additional energy consumption to compensate for the pressure drop.

2. Common treatment technical solutions

1. source control

• pre-drying: Install a freezing dryer or adsorption dryer at the air compressor inlet to reduce the dew point temperature of the air before compression to below the pressure dew point and reduce the amount of condensed water.
• staged compression: Adopt a multi-stage compressed air compressor, and set up an intercooler after each stage of compression to gradually reduce the air temperature and reduce the single compression ratio and the amount of condensed water.

2. terminal treatment

• Air storage tank drainage: An automatic drain valve is set at the bottom of the air storage tank to regularly drain condensed water to prevent accumulated water from entering subsequent pipelines.
• precision filtration: Install a precision filter (such as a 0.01 micron filter element) at the end of the pipeline to intercept residual liquid water and water mist.
• Post-treatment drying: According to the gas quality requirements, select a regenerative dryer (such as non-thermal regeneration, micro-thermal regeneration) or a membrane dryer to reduce the dew point temperature of the compressed air to below-20℃ to meet the demand for high-precision gas.

3. Typical application scenarios

1. General industrial field

• programme: Freeze dryer + automatic drainage of air storage tank + precision filter.
• effect: The dew point temperature of compressed air can be controlled at 3-10℃, meeting the gas needs of most pneumatic tools and automation equipment.

2. High-precision gas use scenarios

• programme: Adsorption dryer + membrane dryer (series)+ precision filter.
• effect: It can reduce the dew point temperature of compressed air to below-40℃ to meet the needs of moisture-sensitive gas such as electronic manufacturing and laboratory instruments.

4. Operation and maintenance management requirements

1. Regular drainage: Check the air storage tank and pipeline low-point drain valve every day to ensure that condensate is drained in time.
2. filter replacement: Precision filter elements need to be replaced regularly by pressing the difference indication or for the duration of use (generally replaced every 3-6 months).
3. dew point monitoring: Set a dew point meter at key gas consumption points to monitor the moisture content of compressed air in real time. If the water exceeds the standard, an alarm will be triggered and standby drying equipment will be started.

V. Supplementary Provisions

This specification applies to the design, selection and operation and maintenance management of compressed air systems within enterprises. When involving special industries or international cooperation, corresponding processing equipment needs to be configured simultaneously in accordance with local standards and gas quality requirements.

By implementing this specification, companies can effectively control the moisture content of compressed air, extend equipment service life, and improve process stability and product quality.