Why solids/liq. Mist is separated from gases/vaps?

Removing liquids and solids from a gas stream is very important in refining and gas processing applications. Effective removal of these contaminants can prevent costly problems and downtime with downstream equipment like compressors, turbines, and burners. In addition, hydrocarbons and solid contaminants can induce foaming in an amine contactor tower and can contribute to premature catalyst changeouts in catalytic processes. In compressors that use oil to lubricate cylinders, the lube oil often gets into the discharge gas causing contamination downstream. A thin film of hydrocarbon deposited on heat exchangers will thicken and coke, decreasing heat transfer efficiency, increasing energy consumption and creating a risk of hot spots and leaks.