Aspen Hysys在模拟炼油厂干气MDEA脱硫过程中的应用

Application of Aspen Hysys in Simulation of MDEA Desulfurization Process of Refinery Dry Gas

MDEA是目前炼油厂干气脱硫技术应用中广泛使用的脱硫剂之一,通过介绍某炼油厂常顶气、减顶气和航煤酸性气组成的混合干气脱硫工艺流程,利用Aspen Hysys流程模拟软件建立胺液脱硫模型,采用胺液脱硫过程处理专用物性包Acid Gas-Chemical Solvent,同时在吸收塔中关联软件自带的H_(2)S-CO_(2)-MDEA-H_(2)O系统。模型运行成功后,将获得的数据与现场实际操作数据进行对比,发现其中最大误差为3.78%,说明Aspen Hysys建立的模拟流程和采用的物性方法具有较高的可信度,可用于优化装置的操作参数。其后,通过工况分析确定了合理的MDEA溶液浓度为32%(质量分数),消耗量为5800kg/h,脱硫干气中H_(2)S含量计算结果为16.0mg/L,与装置实际运行数据平均值16.8mg/L较为接近,误差为4.76%,满足H_(2)S含量控制指标不大于20mg/L的要求。相对于现场使用的8330kg/h的MDEA溶液消耗量,优化后显著降低了MDEA溶液的用量,节省了相关机泵的电耗,经济效益显著。

Currently MDEA is one of the widely used desulfurizers in the desulfurization of refinery dry gas.In this paper,the desulfurization process of mixed dry gas in a refinery,which consists of CDU overhead vapor,VDU overhead vapor and aviation kerosene acid gas,is introduced.Aspen Hysys process simulation software was used to set up amine desulfurization model.Acid Gas-Chemical Solvent,the special physical property package for amine desulfurization process,was used,and the H_(2)S-CO_(2)-MDEA-H_(2)O system that comes with the software was correlated in the absorber.After the successful operation of the model,the data obtained were compared with the actual operation data and the maximum error was found to be 3.78%,indicating that the simulation process established by Aspen Hysys and the physical property method adopted have high reliability and can be used to optimize the operation parameters of the unit.Subsequently,it was determined through case studies that the reasonable concentration of MDEA solution was 32wt%and the consumption was 5800kg/h.The calculated H_(2)S content of desulfurized dry gas was 16.0mg/L,close to the average of the actual operation data of the unit(16.8mg/L),and the error was 4.76%,meeting the requirement that the H_(2)S content should be no more than 20mg/L.Compared with the 8330kg/h of MDEA solution consumed on site,the optimized operation significantly reduced the consumption of MDEA solution and saved the power consumption of related pumps.The economic benefit was remarkable.