There are a multitude of proprietary processes available through licensing for LNG liquefaction, and MEI can perform detailed engineering and other services based on these technologies. These processes include:
- C3-MR method (APCI): Currently the main method. Propane and mixed coolants (nitrogen, methane, ethane and propane) are used as the coolant. Uses fewer exchangers and compressors.
- AP-X method (APCI): As liquefaction trains get larger, they require larger heat exchangers than can be manufactured and transported. The AP-X process increases LNG production capacity by adding LNG sub-coolers utilizing nitrogen coolant, without increasing the size of the main heat exchanger.
- Cascade method (Phillips): This method employs three heat exchangers and sequentially uses propane, ethylene and methane as the coolant. Independent compressors for each exchanger-refrigerant combination are also utilized.
- DMR method (Shell): This method uses two kinds of mixed coolants (an ethane and propane mix and a nitrogen-methane, ethane and propane mix).
- SMR method (Black & Veatch): Referred to as the PRICO process and uses only one kind of mixed coolant.