There are a lot of contaminations like dust, compressor lubricant (mineral or synthetic), condensed beads, acidic condensed liquid as well as oil and hydrocarbon fog in typical air compression system. If these contaminations are not removed, they are bound to contaminate and corrode pipelines, valve, instrument, equipment, which would lead to instrument and control device malfunctions, damage the fineness and finish, increase the maintaining cost of pneumatic equipment, contaminate process and endanger product quality.