硫酸再生装置长周期运行问题分析整改

Analysis and Rectification of the Long-cycle-operation Problems in SAR Device

大庆炼化公司3万t/a硫酸再生装置,采用奥地利P&P工业技术公司湿法废酸再生技术,于2018年12月建成投运,是30万t/a烷基化的配套装置,解决烷基化装置产生的废酸所引发的高额处理费用和中和填埋导致的环境污染问题,属于环保装置。装置由于硫酸露点腐蚀和过程气杂质导致的垢下腐蚀,导热盐换热器频繁发生泄漏,导热盐泄漏进入含酸的过程气中导致尾气NOx排放超标,不仅造成装置非计划停工,还会产生较严重的安全环保事件。目前,国内P&P湿法硫酸再生装置运行周期均<12个月。因此,需要攻克装置的瓶颈问题,从根本上保障装置长周期运行。通过总结装置首次开工以来几个运行周期出现的影响长周期问题和停工检修经验,对影响装置长周期运行的瓶颈问题进行了原因分析,并逐一采取了针对性的整改措施,取得了良好的效果,为国内湿法硫酸再生装置长周期运行提供一定帮助和借鉴。

The 30 kt·a-1 SAR device in Daqing Refining and Chemical Company adopts wet SAR technology of P&P Industrial Technology Company in Austria,which was completed and put into operation in December 2018.It is a supporting device of 300 kt·a-1 alkylation device,which solves the high treatment cost for the spent acid generated by the alkylation device and the environmental pollution problems caused by the neutralization and landfill.It is an environment-friendly device.Due to the sulfuric acid dew-point corrosion and the under-scale corrosion caused by process gas impurities,heat-transfer-salts exchangers of the device leakage frequently,leakage of heat transfer salts into the acidic process gas leads to excess NOx emissions,which not only causes device unplanned shutdown,but also produces more seriously safety and environmental events.At present,the operating cycle of P&P wet SAR devices at home is less than 12 months.Therefore,it is necessary to overcome the bottleneck problems and guarantee the long cycle operation of the device fundamentally.By summarizing the problems that affected device long period operation and the experience of device maintenance since device first operated,the causes of the bottleneck problems affecting device long period operation were analyzed,and the targeted rectification measures were taken one by one,good effect was achieved,which could provide a certain help and reference for the long period operation of the domestic wet SAR devices.