A Gas Compressor is a device used to increase the pressure of a gas by decreasing its volume. Gas compressors are used in various applications where either higher pressures or lower volumes of gas are needed. However, the main purpose of the process is to store and allow the gas/liquid to transport elsewhere or use when required. The wide variety of gases that a typical gas compressor handles consists of argon, carbon dioxide, carbon monoxide, ethane, ethylene, helium, hydrogen, landfill bio gas, methane natural gas, neon, nitrogen, nitrous oxide, oxy-helium, sulphur hexaflouride and xenon. It is employed in numerous applications, including landfill gas, digester gas, fuel gas boosters, vapor recovery, LNG boil-off, and process gas.
The modern day Gas Compressors are designed with efficiency and versatility in mind, providing both performance and maintenance advantages. The diversified industries in which a Gas Compressor holds a significant place are, chemical industry, wet oxidation units, petrochemical plants, oil refineries, polyethylene plants, in life support devices, natural gas handling, jet engines, aircrafts, in refrigeration equipment , in pipeline transport of domestic gas (to move the gas from the production site to the consumer), in submarines (to store gas for later use as buoyancy), etc.
A Gas Compressor performs the following functions :-
- Pressurizes and Circulates gas through the process.
- Enhance conditions for chemical reactions.
- Renders Inert gases to facilitate various safety & control
- Helps in maintaining the appropriate pressure levels by either adding and removing gas or vapors from a process system.
The working of a Gas Compressor involves two main phases. The first phase consists of filling up the cylinder by gas that make its way through the inlet check valve. After that hydraulic fluid (pressurized), which is simultaneously acting on the hydraulic piston, starts compressing the gas of this cylinder. The next step consists of flowing of the compressed gas into a second cylinder which is smaller than the first-one.
In the second phase of the process, the valve changes its position and starts pressurizing hydraulic fluid to the opposite side of the hydraulic piston. This change in position results in moving of the piston and it starts compressing gas, present in the second cylinder. Finally, the gas flows out of this cylinder into the gas line and this process cycle keeps on repeating itself.