to t5 approximately 4 u00b0 f it then goes by pipe 34 through the heat exchanger k2 which initially cooled the entering gas from 85 u00b0 down to 14 u00b0 and this cold gas effluent at t5 4 u00b0 f leaves the heat exchanger k at approximately 75 u00b0 f and goes to a compressor l of conventional design and out to the sales gas pipeline 40 at temperature t6 about 75 u00b0 f there are three liquid gas separators the first one b for the entering cooled feed gas the second one e for the cold entering gas from pipe 16 and the third one g the reflux separator operating on the gas that has been cooled to the lowest temperature in the system at the outlet of the expander f so far only the gas portion of the system has been discussed there is liquid in the bottom of each of the three separators in the case of the first separator b the liquid at the bottom b2 is controlled by level control means and as the level builds up liquid from b2 from the bottom part of the separator b flows out by pipe 47 through a control means 46 to maintain liquid level.