Natural gas Some of these gases include heptane, pentane, propane and other hydrocarbons with molecular weights above methane (). The natural gas transmission lines extend to the natural gas processing plant or unit which removes the higher molecular weighted hydrocarbons to produce natural gas with energy content between . The processed natural gas may then be used for residential, commercial and industrial uses. Natural gas flowing in the distribution lines is called mid-stream natural gas and is often used to power engines which rotate compressors. These compressors are required in the transmission line to pressurize and re-pressurize the mid-stream natural gas as
Liquefied natural gas the calorific value. Due to the sensitivity of liquefaction facilities to sulfur and mercury elements, the gas being sent to the liquefaction process shall be accurately refined and tested in order to assure the minimum possible concentration of these two elements before entering the liquefaction plant, hence there is not much concern about them. However, the main concern is the heating value of gas. Usually natural gas markets can be divided in three markets in terms of heating value: There are some methods to modify the heating value of produced LNG to the desired level. For the purpose of increasing