丙烯回收项目在乙苯装置脱丙烯系统上的应用

The Application of Propylene Recovering Techniques in Propylene Removing System of Ethylbenzene Plants

为进一步提升装置经济效益,实现节能降耗、降本增效,对中国石化青岛炼化9.0×104t/a乙苯装置脱丙烯系统增设丙烯回收单元。脱丙烯系统改造后,现场增设控制阀,装置的开、停工可以利用新加控制阀,由室内DCS控制脱丙烯系统的压力,操作准确、简便、安全。同时,对脱丙烯系统改造后的装置开、停工步骤进行了具体说明。通过对脱丙烯系统的改造,将催化干气直接甩燃料气管网改为进丙烯吸收塔吸收与解析后甩燃料气管网,干气放空量大大减少,脱丙烯系统生产负荷明显增加,大量回收了干气中的富丙烯液化气组分。回收后的富丙烯液化气组分送至催化单元,减少了高价值产品流失。脱丙烯系统改造后,共回收富丙烯液化气组分5493.92t/a,按照市场价格核算,每年创造经济效益2363.16万元。回收丙烯及液化气组分明显增加,改造效果明显。

In order to further increase the economic efficiency of its 9.0 ×104t/a ethylbenzene plant,reduce energy consumption,reduce production cost and enhance efficiency,Sinopec Qingdao Refining Corporation added a propylene recovering unit for the propylene removing system of the plant.After revamping the propylene re-moving system,the company added on-site control valves to start or shut down the plant and to control the pressure of the propylene removing system via an indoor DCS.The operation is accurate,simple and safe.The procedures of turning on and off the plant after the revamping of the propylene removing system have also been specified.Through the revamping of the propylene removing system,in which direct throw of catalytic dry gas into the fuel gas pipeline network was shifted to throw into the fuel gas pipeline network after being absorbed and resolved in the propylene absorption column,the quantity of dry gas emitted into the flare system has dropped significantly,the production load of the propylene removing system has considerably increased and a large quantity of propylene-rich LPG components has been recovered from dry gas.The recov-ered propylene-rich LPG components are transmitted to the catalytic unit,thus reducing the loss of high-value products.After the revamping of the propylene removing system,a total of 5493.92t/a of propylene-rich LPG components have been recovered.At the current market prices,the annual economic benefits from the revamping reach about 23.63 million yuan.The amounts of propylene and LPG components recovered have in-creased dramatically,meaning that the revamping is very effective.