芳烃联合装置中制苯工艺对比及技术发展

Process comparison and technical development of benzeneproduction in aromatics combination unit

芳烃联合装置中主要生产对二甲苯(PX)及苯、甲苯,在目前的研究中多集中在PX的高效节能生产方面,但对其所配套的生产苯、甲苯的制苯联合装置的相关研究报道较少。因此从装置概况、物料平衡、工艺技术、装置改进、能耗等多方面介绍并比较了国内两套典型的芳烃抽提-苯/甲苯联合制苯装置。对比发现新建联合制苯装置通过采用C_(7)馏分预分割、汽提蒸汽流程优化、塔釜积液槽改进、塔含水量控制等技术方案可以大幅度降低装置生产能耗并延长循环溶剂寿命,并提升了装置运行稳定性,折合生产PX产品的能耗仅为1.326 kg/t,在同类装置中具有一定优势。

P-xylene(PX)and benzene/toluene are two mainly products in aromatics combination unit.At present,the research is mostly focused on the efficient and energy-saving production of PX,but there are few reports on the supporting benzene production unit for benzene/toluene.Therefore,the device profiles,material balance,process technology,equipment improvement and energy consumption were used to introduce and compare the two sets of typical domestic aromatics extraction-benzene/toluene combined benzene production plant.The comparative study shows that the new-built combined benzene production unit can significantly reduce the production energy consumption of the unit and prolong the circulation time of solvent by adopting advanced technical schemes such as C_(7) fraction pre segmentation,stripping steam process optimization,improving tower kettle effusion tank and controlling tower water control.The converted energy consumption for producing PX is only 1.326 kg/t,which has certain advantages in similar units.