Abstract: In order to recover propane from oil and gas fields, two improved propane recovery processes are proposed based on the existing patented DHX process, and the three processes are simulated and analyzed by HYSYS. The results show that all the three processes can meet the requirements of propane recovery rate higher than 98% and ethane to propane ratio at the bottom of deethanizer no higher than 1.6%. The patented DHX process is complex. It uses propane refrigeration system and has high equipment investment cost. The improved DHX process Ⅰ and Ⅱ eliminate the propane refrigeration system, simplify the process flow and reduce the equipment investment. The energy consumption of dry gas outlet compressor in the improved DHX process Ⅱ is 47% higher than that of the improved DHX process I. That is to say, the improved DHX process I is superior to both the patented DHX process and the improved DHX process Ⅱ in terms of energy consumption and operability. Therefore, the improved DHX process I is recommended for propane recovery unit for higher propane yield and lower energy consumption.

Key words: DHX process, improved DHX process, simulation, propane recovery rate