PX装置硫含量异常原因分析

Cause Analysis of Abnormal Sulfur Content in PX Unit

盛虹炼化有限公司(连云港)新建一套280万吨/年PX装置,PX装置Ⅱ系列装置于2022年12月开始进行投料试车,2023年1月6月对二甲苯产品合格。2023年1月14日PX装置Ⅱ系列加热炉烟气中二氧化硫呈逐渐上升趋势,后在异构化反应进料、PX产品中的硫含量均出现大幅上涨,并导致了烟气中SO2排放超标、芳烃抽提抽余油博士试验不合格和PX产品硫含量超标等事件发生,装置对各种原因进行逐一排查并采取了调整措施后,于2023年1月28日PX装置系统内的硫含量逐步恢复正常,2023年1月31日2#芳烃抽提装置抽余油博士试验合格。

Shenghong Refining and Chemical Co.Ltd.(Lianyungang)built a new set of 2.8 million tons/year PX unit.The PX unit series-Ⅱ compeleted the commissioning in December 2022,and produced on-specification paraxylene product in January and June 2023.On January 14,2023,the sulfur dioxide in the flue gas of the series-Ⅱ fire furnace of PX unit showed a gradually rising trend,and then the sulfur content in the isomerization reaction liquid feed and PX product increased significantly,which led to the occurrence of incident such as excessive SO2 emission in the flue gas,unqualified doctor test of aromatics extraction raffinate oil,and excessive sulfur content in PX product.After investigating various reasons one by one and taking adjustment measures,the sulfur content in the PX unit gradually recovered to normal value on January 28,2023.On January 31,2023,the raffinate oil of aromatics extraction unit passed the doctor's test.