REFRIGERATION SYSTEM FOR A NATURAL GAS LIQUEFACTION PROCESS

摘要

Provided is an improved refrigeration system forpre-cooling natural gas or cooling a mixed refrigerantfor natural gas liquefaction in a propane refrigerationprocess widely used for the liquefaction of naturalgas. The system comprises a plurality of plate-finheat exchangers preferably arranged in a parallelrelationship for passing a propane refrigerant as avertical flow and pre-cooling natural gas or cooling amixed refrigerant for liquefying natural gas, and athermo siphon drum for the propane refrigerantconsisting of a horizontally disposed, laterallyelongated tank. Because the passages of the heatexchanger for the natural gas or the mixed refrigerantextend over their entire length in mutually separaterelationship, even when the propane refrigerant, thenatural gas or the mixed refrigerant is in both gas andliquid phases, a high efficiency of heat transfer canbe attained, and the size of the heat exchanger can bereduced. In particular, from an economic view point,it is preferable if the thermo siphon drum serves alsoas a flash tank.