关键词: 乙烯精馏塔, 釜式, 中间再沸器, 热泵精馏

Abstract: By comparing the characteristics of thermosiphon and kettle side reboiler, the effects of heavy components accumulation caused by inner circulation of kettle reboiler on heat transfer are studied, especially on bubble point, heat transfer temperature difference and boiling film coefficient. Based on the ethylene fractionator side kettle reboiler combined with heat pump, the heat transfer calculation under fractionator side extraction and internal circulation fluid is compared. The results show that the bubble point of fluid in kettle rises by 1.76 ℃, and the heat transfer temperature difference calculated by fractionator side extraction is 16.3% larger than that by internal circulation fluid. The design based on fractionator side extraction can't meet the heat transfer requirement even though the original design margin 9.1% is taken into account. A more precise calculation method and suggestion for heat transfer of circulating logistics are put forward. It provides basis for heat transfer design of ethylene distillation column and side kettle reboiler, especially under small temperature difference.

Key words: ethylene fractionator, kettle reboiler, side reboiler, heat pump distillation