AP-XTM LNG process offers an attractive means to significantly reduce the specific capital cost of LNG. The AP-XTM LNG process can be configured with propane or mixed refrigerant pre-cooling as required by ambient conditions and plant location, and it is expected to provide the lowest unit cost of LNG on the market today. The economy of scale is superior to splitting equipment into two process trains or duplicating equipment. The first AP-XTM trains to be built will have a nominal capacity of 7.8 MTA LNG.

The AP-XTM concept is depicted in Figure 3. This process retains the concept of single train equipment up to the highest capacity and can employ the Split MRTM compressor configuration. The addition of the sub-cooling cycle using nitrogen as working fluid reduces the propane refrigeration and mixed refrigerant compression duty per tonne of LNG. Plant capacities can be steadily increased from 7.5 to 10 MTA by increasing the amount of driver power consumed using two or three frame 9 gas turbines. It has been shown that natural gas liquefaction capacities of up to 10 MTA and beyond can be achieved with single train compression equipment for mixed refrigerant and nitrogen.

Using AP-XTM technology at approximately 7.5 MTA LNG the number of propane compression casings is increased to two in the same arrangement as for the C3MR process. Air Products manufactures and supplies the cryogenic machinery necessary for the nitrogen expansion required in the AP-XTM process from its manufacturing facility in the United States.