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In order to take full advantage of the lower concentration of ethylene in FCC dry gas resources, some of the country's refineries and research institutes jointly developed dry gas directly ethylbenzene process. But in the actual production of the process there is a major problem: the dry gas in a higher concentration of propylene, benzene and occurrence of side reactions, dry gas ethylbenzene process benzene consumption, increased energy consumption and the amount of catalyst loss. Therefore, reducing the raw material gas in the concentration of propylene is an urgent need to solve the problem. Existing processes, the major absorption and stabilization system by adjusting FCC to reduce propylene concentration. This method requires increasing absorbent flow and reduce the absorption operating temperature, a significant increase in the energy consumption of the process and the operation load of the column. On the basis of the existing process, the new technology of membrane separation technology coupled with absorption stabilization system, and using HYSYS simulation meet lower propylene concentration of ethylbenzene feedstock dry gas, in the case of less energy consumption increases, requirements. This thesis is based on refinery actual process and device calibration data, applications HYSYS absorption stabilization system model, the simulated results are in good agreement with the actual production situation, to verify the reliability of the model. To establish on the basis of absorption and stabilization system model, adjust the the absorbent flow and temperature, the stabilizer reflux ratio, desorption tower feed temperature and other parameters, the effects of various factors on the device energy consumption and system products dry gas, liquefied petroleum gas and stable quality of gasoline impact; and changing the system operating parameters, and the propylene in the dry gas is reduced by 1.1% (v) the existing process to 0.3% (v), the total cooling and heating load is 2.08 times and 2.22 times, and can not The fractionation system provides heat match. Unable to match the the fractionation system provides heat conditions in view of the adjustable parameters, the paper proposes a new membrane separation coupled with absorption stabilization system process, including the series of membrane separation absorption tower, absorption tower after a series of membrane separation and re-absorption tower series membrane separation three new technology, and the application the HYSYS software on the new process was simulated. The results show that, using the new technology of membrane separation technology can significantly reduce the energy consumption of the system, indicators of dry gas propylene concentration 0.3% (v), the cooling load of the three new processes were reduced by 42.4%, 28.2%, 29.2% of the heat load reduces by 44.5%, 31.3%, 31.6%. Considering the cooling and heating load of the programs, the tower load and economic efficiency, absorption tower series of membrane separation is the best new technology to reduce the propylene concentration. System heat analysis, we can see the best new technology and the the fractionation system provides heat match with fractionation system as a whole is applied to the actual production.
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