合成氨装置蒸汽透平结垢原因分析及对策

结合中国石油吉林石化公司化肥厂合成氨装置运行的实际工况，分析了四大机组透平发生结垢现象的原因，并采取了相应的改进措施。结果表明，驱动透平的高压蒸汽中Ｎａ＋及ＳｉＯ２的质量浓度超标是导致结垢的主要因素。采用活性分子膜超微过滤组合多官能团纤维吸附凝结水处理技术对合成氨冷凝液系统进行了改造，并严格水质及蒸汽品质的控制指标，其中含Ｎａ＋，ＳｉＯ２质量浓度均不大于１５μｇ／Ｌ。实施上述措施后，在为期９个月的运行周期内，四大机组透平运行稳定，减少蒸汽消耗量约１０ｔ／ｈ，减少循环水补水量２８万ｔ，减少缓蚀剂、阻垢剂消耗量２５ｔ，有效解决了透平结垢及蒸汽管网失衡问题。

Cause analysis and countermeasures for steam turbine scaling in synthesis ammonia unit

According to the operating mode of synthetic ammonia unit in the Fertilizer Factory of Jilin Petrochemical Company,PetroChina,the scaling cause of 4 steam turbine sets was analyzed,and the corresponding measures were put into effect.The results showed that the turbine scaling was mainly attributed to the overproof Na ＋ and SiO2 contained in high-pressure steam which drave the turbine.The condensed water system in synthetic ammonia unit was revamped based on a combined treatment technology of active molecule membrance ultrafiltration and multifunctional fiber adsorption,and the mass concentrations of Na ＋ and SiO2 in boiler water,condensed water and high-pressure steam were strictly controlled to no more than 15 μg/L.After completing all the measures,within a operation cycle of 9 months,4 steam turbine sets worked stably,the steam consumption was reduced by about 10 t/h,the supplementary amount of circulation water was saved 280 kt,and the consumption of corrosion and scaling inhibitors was decreased by 25 t,indicating that the problems of turbine scaling and related imbalance of steam network were solved effectively.