真组分法模拟乙烯装置急冷系统

Simulation of quench system of ethylene plant by real components method

为了准确模拟乙烯装置的急冷系统,用真组分法代替虚拟组分法来计算乙烯装置急冷系统馏分油的物性。根据馏分油的实沸点曲线,采用虚拟组分的切割方法,将馏分油实沸点曲线切割成一系列窄区间,结合密度曲线在裂解产物组分所属的化合物类型中选择表征该区间真组分,采用优化的方法确定真组分的质量分数和体积分数。对于沸点高于500℃的馏分,仍采用虚拟组分法计算馏分油的性质。本方法应用到国内某乙烯装置急冷过程模拟中,结果与实际值符合较好,表明真组分法可作为乙烯装置急冷系统有效计算方法之一。

To simulate quench system exactly, the pyrolysis oil in quench system was characterized by real components instead of pseudo-components. According to the cutting measures of pseudo-components, the True Boiling Point （TBP） curve was cut into a series of narrow zones. Real components in the zones were selected and characterized by combining with density curve in pyrolysis products of compound groups. The mass fraction and volume fraction of real components were calculated by optimization method. But the pyrolysis oil with a boiling point higher than 500 ℃ was characterized by pseudo-components. Simulation results of one quench system used in one ethylene plant in China were consistent with the measured results. This new approach is reliable and effective for quench system simulation of ethylene plant.