入炉煤总氯量对粗苯含氯超标的影响分析

Analysis of the effects of total chlorine in the furnace coal on rough benzenecontent exceeding the standard analysis

粗苯为1种重要的化工原料,其主要用于深加工制苯、甲苯、二甲苯等产品。粗苯含氯高会严重腐蚀管道,对后续苯加氢等深加工利用带来危害。经对化工产品生产工艺以及入炉煤综合分析研判,基于粗苯含氯情况重点从入炉煤、介质、冷却器清洗、换热设备串漏等方面排查粗苯含氯增高的影响因素,并结合煤中氯的释放、洗煤对精煤含氯的影响探讨入炉煤含氯量与粗苯含氯量的关系。结果表明:高氯煤是造成粗苯含氯升高的直接因素,煤在碳化室热解过程中,煤中氯离子会以HCl的形式析出并进入荒煤气与化产回收系统中。当入炉煤总氯量偏高时,严重影响粗苯等化工产品的质量。在化工产品生产工艺正常的情况下,入炉煤中总氯含量应低于0.1%,以保证粗苯含氯量控制在10μg/g以内。

Rough benzene is mainly used for deep-processing benzene,toluene,dyshayne and other products,and it is an important type of chemical raw material.High chlorine content in crude benzene can seriously corrode pipelines,which will cause harm to deep processing and utilization of subsequent phenyl hydrogen.After comprehensive analysis and judgment of production technology and integrated coal,based on coarse benzene-based chlorine content,the influencing factors of increased chlorine content in crude benzene were detected from the aspects such as incoming coal,medium,cooler cleaning,and leakage of heat exchange equipment.Combined with the release of chlorine in coal and the impact of coal washing on the chlorine content of clean coal,the relationship between the chlorine content of incoming coal and the chlorine content of crude benzene were explored.The results indicate that high chlorine coal is the direct factor causing the increase in chlorine content in crude benzene,during the pyrolysis of coal in the carbonization chamber,chloride ions in coal will be separated in the form of HCl and enter into the raw gas and chemical product recovery system When the total chlorine content ofincoming coal is too high,it seriously affects the quality of chemical products such as crude benzene.Under normal chemical production processes,the total chlorine content in the incoming coal should be less than 0.1%to ensure that the chlorine content of crude benzene is controlled within 10μg/g.