Hi everyone!

If there is some N2 in the flow of natural gas entering the liquefaction plant (the picture of open Linde cycle is attached), a large percentage of N2 is not liquefied after passing through the expansion valve and leaves the separator as flash gas.

Since the flash gas, which has a higher percentage of nitrogen than the feed gas, recovers to the liquefaction cycle again, it causes the N2 concentration in the cycle to increase over time, which can disrupt the cycle's performance.

What is the best solution to prevent the gradual increase of N2 concentration in the liquefaction cycle?