Research On Influencing Factors And Control Theory Of Sulfur And Chlorine In Coking Light Benzol

Coking light benzol is one of the most important coking chemical products,but the sulfur and chlorine substances in it will reduce product quality and affect sales price.At the same time,it will corrode equipment and shorten catalyst life in subsequent processing.Therefore,it is of great practical significance to study the influencing factors of sulfur and chlorine content in coking light benzol and explore the control strategy of its source and process.In this paper,the typical coking light benzol production process in China is taken as the research object.The sampling device for sulfur and chlorine components in coke oven gas,as well as the pretreatment and detection methods of samples are designed.The content and form of sulfur and chlorine in coal blending coking,gas purification process,benzol elution process and industrial water use process are systematically investigated.The formation and change of sulfur and chlorine components in the production process are explored.The main results are as follows:The direct factor affecting the sulfur content in coking light benzol is the organic sulfur content in gas,but its main source is the sulfur in blended coal.The results show that the sulfur content in light benzol is positively correlated with the total sulfur and iron sulfide sulfur content in blended coal.The gas purification process has different effects on different forms of sulfur in the gas.H₂S is most affected by the desulfurization section,and the removal rate is greater than 99%.The removal rate of organic sulfur is related to the type of desulfurization catalyst.CH₃SH is most affected by the ammonium sulfate section,and the removal rate is about 76%.The thiophene homologue is most affected by the benzol washing section,and the removal rate is about 81.5%.CS₂ is most affected by the ammonium sulfate section,and the removal rate is about 74%.The direct factor affecting the chlorine content in coking light benzol is the chlorine content in gas and wash oil,but the main source is the chlorine in blended coal.The results show that the chlorine content in light benzol is positively correlated with the total chlorine content of blended coal.The chlorine content in coal gas is related to the chlorine content in desulfurization solution,ammonium sulfate mother liquid,condensate and process operation parameters,and the final cooling tower has obvious dechlorination effect.In the benzol elution section,the chlorine in the wash oil will be transferred to light benzol.Based on this,this paper proposes a sulfur and chlorine control strategy:optimizing coal blending to control the sulfur and chlorine content in coal within 1.15%and0.15%,respectively;the removal rate of organic sulfur was increased to 32.6%by using the new desulfurization catalyst.Optimize process operating parameters to suppress gas-liquid entrainment;by controlling the chlorine content of the condensate,the chlorine removal rate was increased to 90%.The contents of sulfur and chlorine in washing oil were controlled within 6000 mg/L and 7 mg/L respectively.Finally,the content of sulfur in coking light benzol was stably controlled within 5500 mg/kg,and the content of chlorine was controlled within 15 mg/kg.