Natural gas processing technology refrigeration

There are three main methods used to chill natural gas into its liquid constituents: refrigeration, pressure reduction, and expansion. Refrigeration uses an external refrigeration system to cool the gas stream. Pressure reduction uses a pressure reducing valve to lower the pressure and temperature. Expansion utilizes the energy released when gas at high pressure and temperature expands through a compressor-expander, lowering the temperature. Each method recovers different percentages of the heavier hydrocarbons like ethane, propane, and butanes. Cryogenics, a more advanced expansion method, can recover up to 95% of ethane compared to 70-80% for other methods.