乙烯装置低排放开工

Low-emission Startup of Ethylene Plant

目前乙烯装置开工普遍采用有乙烯倒开车方案。先启动丙烯制冷压缩机和乙烯制冷压缩机,再启动裂解气压缩机并进行氮气运行。用氮气作为介质,乙烯和丙烯为冷剂对冷箱、脱甲烷塔等深冷系统进行预冷,同时引进乙烯、丙烯对乙烯精馏塔和丙烯精馏塔进行全回流运转。在深冷系统预冷完成后裂解气压缩机引进天然气提前进行分离系统预开车,打通从裂解气压缩机到冷箱、脱甲烷塔、脱乙烷塔、高压脱丙烷塔及碳二加氢反应器的整个流程。

At present, ethylene plant is generally started up in the reverse sequence. Propylene refrigeration compressor and ethylene refrigeration compressor are started first, and then cracking gas compressor is started and nitrogen is introduced. Nitrogen is used as the medium and ethylene and propylene are used as the cold agent to precool the cryogenic systems such as cold box and demethanizer, and ethylene and propylene are introduced to achieve the total reflux operation of ethylene rectification column and propylene rectification column. After the precooling of cryogenic systems, natural gas is introduced into the cracking gas compressor to pre-start the separation system in advance, so as to get through the whole process from cracking gas compressor to cold box, demethanizer, deethanizer, high-pressure depropanizer and C 2 hydrogenation reactor.