【作者】 刘猛；

【导师】 王健红；

【作者基本信息】 北京化工大学 ， 化学工程， 2002， 硕士

【摘要】 本课题的任务是对脂肪醇装置204单元进行模拟计算,并通过改变设备的操作参数来优化装置的性能。该工艺过程的特点是流程结构复杂,组分繁多,体系非理想性强。甲酯的预馏塔和精馏塔是本工艺过程中两种典型的分离设备,文中对这两种设备进行了深入的分析和论证后,利用稳态的平衡级模型进行模拟计算甲酯的预馏塔,并且利用动态的多组元精馏经验计算方法和最小热负荷动态模型来优化甲酯的精馏塔。由于体系的组分多达30种,且非理想性强,故选则合适的轻、重关键组分以及准确地计算汽液平衡数据是甲酯精馏过程模拟计算的关键。文中利用模型分子法对次轻、重组分进行评估,并根据其挥发度、分子量和密度等参数对其进行合并和拆分。对于轻、重关键组分,文中利用正构烷烃模型分子法,再根据Lagrange插值公式,确定其比例组成。同时文中又利用基团贡献模型(UNIFAC、改进UNIFAC(Lyngby)、改进UNIFAC(Dortmund)、ASOG)和状态方程(SRK、PR、维里方程)交叉结合的方法,预测甲酯—甘油二酸脂体系的汽液相平衡,通过与现场数据进行比较发现, SRK方程+改进UNIFAC模型能更好地描述该体系的热力学性质;通过分析其预测的汽液平衡数据可知,精馏塔最佳的操作温度范围为205~213℃。在精馏塔的模拟和优化过程中,利用多组元精馏的经验计算方法和非平衡级的最小热负荷模型来优化精馏塔操作温度,得出最佳值为210℃,并使精馏塔在该温度下的热负荷降低了19.1%。更多还原

【Abstract】 This paper iS mainly to simulate the process of Me—Ester pre—distillation andoptimize the performance of equipment of Me—Ester distillation by altering itsoperating parameter.The characteristic of the technologic process iS the complicatedmakeup,numerous components and the highly non-ideal system.The towers ofpre—distillation and distillation of Me—Ester are the typical separating equipments.Thisdissertation is mainly to simulate pre-distillation of Me—Ester by the stabilegrade-equilibrium model and optimize the distillation of Me—Ester by the dynamicUFG model and minimal heating charge model,after analyzing and demonstrating theequipment. It is very important to choose the reasonable sub—important component andcalculate the VLE during the simulation of Me—Ester distillation because of thecomplicated makeup,numerous components and the highly non-ideal system.Themethod of model molecule Was applied to evaluate the sub-important components andcombine or disconnect it by the volatility,molecular weight and density.Meanwhile,with regard to the key component,the model molecule of alkyrlation and formula ofLagrange were used to conforrn the components.The group contribution methods,based on the cross connection of UNIFAC model(original UNIFAC model,modifiedUNIFAC model(Dortmund),modified UNIFAC model(Lyngby),ASOG model)andthe state equation(SRK equation,PR equation,Van Ness equation),were applied topredict VLE of me.ester system.Compared with the located data,we founded thatmodel of SRK equation+modified UNIFAC model(Dortmund)may better depict thethermo-dynamics character of me-ester+di—clycerid system than others connection.By the analyze of predicted VLE data,the optimum temperature of operation Was205—213℃ in the distillation tower.The optimum operating temperature ofdistillation tower was adjusted to 210℃and the heating charge of distillation towerwas reduced by 19.1%by means of minimal heating charge model of flashes。更多还原