A filter is a device that prevents the passage of waste materials in a fluid such as air, water, or oil. An air filter is a fibrous device that removes solid particles such as dust, dirt and, bacteria from the air. These contaminants attach to the constituent fibers of filter when they enter it and then, will not pass through. Therefore, the smaller the pores in the filter, the higher the filter efficiency, and the smaller particles can be prevented from passing through.

One of the applications of filters is compressors. Compressors are widely used in all industries, especially oil, gas, and petrochemical industries. The compressor exhaust air contains water vapor, fine dust particles, corrosive particles, bacteria, and very fine oil particles, which in combination leave sludge-like substances with acidic properties. Due to high pressure, a layer of these materials forms inside the tank and causes serious damage to compressed air equipment, pneumatic valves, jacks, and other sensitive parts of devices. According to the important role of compressors in various processes, the quality of the passing fluid has a significant effect in increasing the lifespan of various compressor components and also reducing the stopping time of the compressor. Increasing the efficiency of the filter is usually caused by increasing the density of the filter bed fibers, which leads to an increase in pressure drop and thus an increase in energy consumption. The use of filters with nanofiber coating increases the efficiency of the filter in absorbing finer particles without significantly increasing the pressure drop of the filter compared to the Nano structure free filter, which increases the quality of the passing fluid and thus increases the lifespan of equipment and reduces the time of repairing and stopping. Azad Filter Company is industrially producing and supplying nanostructured air filters to the market. This product, which is specifically used in filtering turbine inlet air, has a higher efficiency than conventional filters.