低温甲醇洗尾气中CO含量高的原因分析及优化措施

Cause analysis and optimization measures of high carbon monoxide content in rectisol off gas

关键词:  低温甲醇洗  尾气  CO  有效气  气提氢气 

Key words:  rectisol  off gas  carbon monoxide  recycle gas  stripping hydrogen

摘要:

目的 降低尾气中的CO摩尔分数至0.20%以下,达到设计指标。方法 分析了低温甲醇洗尾气中CO含量高的原因,对系统进行了优化操作；同时在低温甲醇洗系统富甲醇次中压闪蒸段增加了气提氢气工艺,并对气提氢气量进行了优化调整；此外针对系统冷量回收利用不平衡不充分的问题进行了技术改造。结果 优化改造后,低温甲醇洗尾气中的CO摩尔分数降至0.19%,达到了设计指标要求,实现了节能降耗的目的。结论 系统优化操作中,增加气提氢气的设计、优化调整气提氢气量以及对系统冷量回收利用的技术改造,可以有效降低尾气中CO含量,并使其达到设计指标。

Abstract:

Objective The mole fraction of carbon monoxide in rectisol off gas is reduced below 0.20% in order to meet the design index. Methods The reasons for the high carbon monoxide content in rectisol off gas were analyzed, and the system was optimized. Furthermore, the stripping hydrogen was designed in the secondary intermediate pressure flash distillation section of the rectisol and the amount adjustment was optimized. Apart from that, technical transformation was carried out to address the problem of unbalanced and insufficient cooling capacity recovery and utilization in the system. Results After optimization, the mole fraction of carbon monoxide in rectisol off gas decreased to 0.19%, which meets the design index requirements and realizes the purpose of energy saving and consumption reduction. Conclusion sThe system optimization operation, the design and optimization adjustment of stripping hydrogen and the technical transformation can effectively reduce the content of the carbon monoxide in the off gas to reach the design index.