新建及改建硫铁矿制酸低温热回收装置运行总结

Operation summary on low-temperature heat recovery unit of new-built and reconstruction pyrite-based sulphuric acid plants

介绍了新建200 kt/a硫铁矿制酸低温热回收装置和150 kt/a硫铁矿制酸系统改建低温热回收装置的工艺流程及运行情况。其共同点是热回收塔前不设置省煤器,在低温热回收装置中设置中压锅炉给水加热器代替原有省煤器加热中压锅炉给水。区别则是后者是低温热回收装置高温串酸先进入中压给水加热器再进入蒸发器给水加热器,最后进入脱盐水加热器。通过对比运行参数,阐明低温热回收装置的主要影响因素。2套装置成功开车的经验及稳定运行数据说明硫铁矿制酸系统配置低温热回收装置切实可行,并有较好的经济效益。

Process flows and operation of new-buih low-temperature heat recovery unit of 200 kt/a pyrite-based sulphuric acid plant and that of 150 kt/a are introduced. Their common points are not setting economizers before heat recovery towers, setting medi- um-pressure boiler feedwater heater instead of original economizer heating medium-pressure boiler feedwater, yet their differences are acid high-temperature crossflow from low-temperature heat recovery unit first enter medium-pressure feedwater heater, then enter evapo- rator feodwater heater, and finally enter desalted water heater. By comparing operation parameters, main influencing factors of low-tem- perature beat recovery unit are described. Successful experiences and stable operation data shows it is feasible that pyrite-basod sulphu- fie acid plant eonflgurated with low-temperature heat reeovery unit and achieve better economic efficiency.