LAUSR

Abstract The dual mixed refrigerant liquefaction process and its key equipment applied in FLNG (floating liquefied natural gas) suffer performance deterioration due to the offshore conditions. In order to improve the offshore adaptability of FLNG dual mixed refrigerant liquefaction process, the experimental device of FLNG dual mixed refrigerant liquefaction process, the numerical simulation model and the visualization experimental device of falling film flow are developed. Multi-scale marine adaptability is studied from the aspects of the liquefaction process and its key equipment (meter scale) and liquid film thickness distribution (micron to millimeter scale). The results show that the effect of offshore conditions is more obvious on the spiral wound heat exchanger (SWHE) than the plate-fin heat exchanger (PFHE) of precooling circuit and the low temperature throttle valve of natural gas. It is recommended to use the corrugated tube with the diameter difference of 2 mm in the FLNG spiral wound heat exchanger to improve the offshore adaptability of dual mixed refrigerant liquefaction process.