三塔双效甲醇精馏工艺的操作优化和技术改造

Operation optimization and technical transformation of three-tower dual-effect methanol distillation process

介绍了目前国内甲醇的生产现状,明确了节能改造对甲醇装置生产运行的重要性。阐述了某100万t/a甲醇装置三塔双效甲醇精馏单元的工艺流程,从杂醇油采出优化、蒸汽消耗减少、不凝气中甲醇回收、粗甲醇泵变频节能、地下槽放空尾气中甲醇回收、甲醇精馏机泵回流阀操作优化等方面进行了技术改造。改造后,甲醇能耗由1490 kgce/t降低至1401 kgce/t,基本达到煤制甲醇标杆能耗的要求。

The current methanol production status in China was introduced,and the importance of energy-saving transformation for the production and operation of methanol plant was elaborated.The process flow of a 1 million t/a methanol plant three-tower dual-effect methanol distillation unit was described,and the operation optimization and technical transformation were carried out from the aspects of fusel oil extraction optimization,steam consumption reduction,methanol recovery in non-condensable gas,variable frequency and energy saving of crude methanol pump,methanol recovery in vent tail gas of underground tank,and operation optimization of methanol rectification pump reflux valve.After the renovation,the methanol energy consumption was reduced from 1490 kgce/t to 1401 kgce/t,basically meeting the benchmark energy consumption requirements of coal to methanol.