导　　师： 马海洪

学科专业： 081702

授予学位： 硕士

作　　者： ;

机构地区： 天津大学

摘　　要： 精对苯二甲酸/(PTA/)主要用于生产PET/(聚对苯二甲酸乙二醇酯/)树脂和聚酯纤维,它是由对二甲苯在醋酸溶剂中通过空气液相氧化制取,采用醋酸钴、醋酸锰、四溴乙烷或溴化氢做催化剂。目前,国内引进的PTA生产技术主要是美国Amoco公司,日本三井油化和英国ICI公司专利技术。 论文主要对粗对苯二甲酸生产中溶剂回收系统进行研究,利用化工流程模拟软件对现有生产装置不同醋酸回收工艺进行了模拟计算,验证了计算软件和计算方法的可靠性,在此基础上完成了年产50万吨PTA生产装置醋酸共沸脱水工艺流程开发,确定了较佳工艺条件,并对不同共沸剂醋酸共沸回收工艺进行了经济性比较。 研究过程中首先对醋酸正丁酯为共沸剂年产25万吨PTA装置醋酸回收系统进行模拟,分别对共沸脱水塔和溶剂回收塔进行计算,其中溶剂脱水塔及回收塔的气、液、液平衡计算用NRTL方程,倾析器用UNIQUAC方程预测较好,气相非理想性的校正用Hayden-O’Connell方程。然后对现有装置以醋酸正丙酯为共沸剂的醋酸回收工艺流程进行模拟,其中气、液、液平衡的计算均用UNIQUAC方程,气相非理想性的校正用Hayden-O’Connell方程。模拟计算结果与工业实际操作数据吻合较好,验证了计算方法的正确性。 在此基础上,将已验证的热力学模型方程用于国产化年产50万吨PTA醋酸回收工艺的开发。分别对国产化醋酸丁酯共沸剂醋酸回收工艺和醋酸正丙酯共沸剂醋酸回收工艺进行模拟计算,并完成了关键设备的设计计算。模拟计算过程中详细讨论了进料位置、理论板数、回流比等工艺参数对精馏过程的影响。确定了满足分离要求的较优的工艺设计参数。最后将两种工艺的经济性进行了综合比较。 Purified terephthalic acid /(PTA/) is useful in a diverse variety of industrial applications. For example, PTA is starting material for producing polyesters including polyethylene terephthalate. PTA is typically produced by a reaction of paraxylene with molecular oxygen in the presence of catalysts. During the production process, acetic acid is used as a solvent of terephthalic acid. Presently, there are mainly three patent technologys have been employed in the PTA plants. They are Amoco technology, ICI technology and MPC technology. This paper focuses attention on the research and analysis of the recovery of acetic acid coming from oxidation section. The model of the flow process which was industrialized was set up using chemical software tool. The simulation result shows that the selected method suits the system well. Based on that, a new process scheme of acetic acid dehydration system was put forward for certain domestic plant which produces PTA 50t//a. Optimum process design and operating condition were ascertained. Investment and energy consumption of two methods were compared. First of all, the acetic acid dehydration process with normal butyl acetate as entrainer simulated for certain domestic plant which product PTA 25t//a. The decanter, the solvent azeotropic distillation tower and the recovery tower were calculated respectively using DECANTER and RADFRAC models. Due to the non-ideal behavior, NRTL-HOC and UNIQUAC-HOC model was used to depict vapor-liquid phase equilibrium behavior of this system. In addition, another acetic acid dehydration system was simulated. In that, normal propyl acetate was entrainer. UNIQUAC-HOC model as the global property methods was used to calculate the DECANTER and RADFRAC models. The appropriate convergence method and order were selected. The results of simulation accord with the operating data well, which proved that the calculation method and the software are credible. On the basis of that, a new acetic acid dehydration process, in that normal butyl acetat

关 键 词： 醋酸脱水 共沸精馏 醋酸正丁酯 醋酸正丙酯 模拟计算

领　　域： [化学工程]