Application of compressed air filters in oxygen plants  

Compressed air filters play a vital and indispensable role in oxygen plants. Their core task is to protect expensive and sophisticated air separation units from contamination and damage by impurities in the air, ensuring safe, efficient and continuous production of high-purity oxygen, nitrogen and other gases.

The following are the main applications and importance of compressed air filters in oxygen plants:

1. Protect air compressors and post-processing equipment:

Intake filtration: Install a high-efficiency filter (usually a primary or medium-efficiency filter) at the inlet of the air compressor to remove larger particles such as dust, pollen, and insects in the air. This is the first line of defense to protect the impeller, cylinder, valve and other parts of the air compressor from wear and scaling.

Protect the aftercooler and gas-liquid separator: The pre-filter reduces the particles entering the aftercooler to prevent it from clogging the heat exchange channel. At the same time, reducing the solid impurities entering the gas-liquid separator helps it separate liquid water and oil more effectively.

2. Deeply purify the air (core role):

After compression, cooling and preliminary separation of liquid water, the compressed air still contains gaseous water vapor, oil vapor/oil mist, fine solid particles, microorganisms and harmful gases (such as CO₂, hydrocarbons, SOx, NOx, etc., depending on the ambient air quality and the type of air compressor). These impurities are fatal to the air separation unit.

The role of the compressed air filter at this stage:

Coalescing filter: Efficiently remove liquid water, oil mist and solid particles in compressed air (usually up to 0.01 µm, and the oil mist content is reduced to below 0.01 mg/m³). This is one of the most critical protective barriers before the molecular sieve adsorber.

Activated carbon filter: Specially used to adsorb oil vapor, hydrocarbon vapor and odor in compressed air. It is particularly important for areas using oil-lubricated air compressors or with poor air quality. It is the last line of defense for oil separation to protect the molecular sieve and air separation cold box.

High-efficiency sterilizing filter: In some applications where there are strict requirements on the microbial content of the product gas (such as medical oxygen), a sterilizing filter may be installed on the final product gas path.