鲁奇低温甲醇洗净化气总硫超标原因及对策

Cause Analysis and Countermeasure of Total Sulfur Exceeding Standard of Lurgi Low Temperature Methanol Washing Purif ication Gas

结合某煤制烯烃项目低温甲醇洗装置自原始开车以来净化气中总硫含量超标问题,从低温甲醇洗工艺原理出发,进行了原因分析和相应的改造。通过增加主洗甲醇循环量、降低循环水的温度、调整气提氮气的量控制酸性气的量、解决热再生塔底再沸器和塔顶冷凝器内漏问题、控制甲醇系统中的氨含量、对贫甲醇过滤器进行切换清洗等措施,有效提高了贫甲醇的品质,最终使净化气中的总硫由手动分析的0.15 mg/L降低至0.06 mg/L,满足了生产需求,使装置得到安全平稳运行。

Combined with the problem that the total sulfur content in the purified gas of the low temperature methanol washing unit of a coal to olef in project has exceeded the standard since the original start-up,the cause analysis and corresponding transformation are carried out from the principle of the low temperature methanol washing process.The quality of lean methanol was effectively improved by increasing the circulating volume of main wash methanol,reducing the temperature of circulating water,adjusting the amount of stripping nitrogen,controlling the amount of acid gas,solving the internal leakage problem of reboiler at the bottom of thermal regeneration tower and condenser at the top of tower,controlling the ammonia content in methanol system,and switching and cleaning the lean methanol filter.Finally,the total sulfur in the purified gas was reduced from 0.15 mg/L by manual analysis to 0.06 mg/L,which met the production demand and made the unit operate safely and smoothly.