新工科背景下校企合作培养化学工程高素质复合型人才的思考

新工科建设对化学工程科技人才的学科知识、专业能力、综合素质提出了更高要求,而校企合作是培养化学工程高素质复合型人才的必由之路。文章从依托生产平台、校企导师协作指导、合作攻关项目、跨专业交流、重视工程管理教育、优化考核制度六个方面探讨了校企合作培养研究生的策略,并分析了研究生自身能力的提升机制。     

工业流化床聚乙烯树脂性能模型的研究

本文首先分析了聚乙烯树脂熔融指数和密度变化的影响因素,建立了流化床动态过程中聚合物性能指标的递椎关系和工业流化床乙烯气相聚合过程产品质量的预测模型,利用乙烯气相（共）聚合过程中不同工艺条件下树脂的质量数据,对模型参数进行了优化,提出由于影响因素的相互关联,熔融指数和密度的控制应该联合进行;熔融指数和密度的计算值与测量值之间的平均误差分别为8.19%和0.13％。预测精度满足要求,模型可以应用于具体的工业生产过程。     

Study on Optimal Strategy of Grade Transition in Industrial Fluidized Bed Gas-Phase Polyethylene Production Process

A model of grade transition is presented for a commercialized fluidized bed gas-phase polyethylene production process. The quantity of off-specification product and the time of grade transition can be minimized by the optimization of operating variables, such as polymerization temperature, the ratio of hydrogen to ethylene, the ratio of co-monomer to ethylene, feed rate of catalyst, and bed level. A new performance index, the ratio of melt flow (MFR), is included in the objective function, for restraining the sharp adjustment of operation variables and narrowing the distribution of molecular weight of the resin. It is recommended that catalyst feed rate and bed level are decreased in order to reduce the grade transition time and the quantity of off-specification product. This optimization problem is solved by an algorithm of sequential quadratic programming (SQP) in MATLAB. There is considerable difference between the forward transition and reverse transition of grade with regard to the operating variab     

迭代动态规划在树脂牌号切换最优化模型中的应用

本文运用迭代动态规划求解牌号切换模型的最优化问题,有效地避免了运用一般方法求解系统最优化问题时的Ｈａｍｉｌｔｏｎ－Ｊａｃｏｂｉ－Ｂｅｌｌｍａｎ方程以及高维系统可能出现的计算量激增的问题,成功地解得树脂牌号切换过程产生的过渡料数量最少时聚合温度、氯气和共聚单体的浓度、催化剂流率和料位高度等５个操作变量的最优轨迹。     

工业流化床乙烯气相共聚合过程分析

通过对Unipol聚乙烯生产工艺的分析,指出了表征树脂质量的性能指标,进而提出了影响树脂性能指标的主要操作变量.     

工程伦理与化工设计课程的融合

文章探讨了如何在化工设计课程中融入工程伦理教育,提出在化工设计课程教学中结合案例分析培养学生的工程伦理观念,通过在大学生化工设计竞赛中设置与工程伦理相关的评分项,引导学生按照化学工程伦理的要求和规范进行设计。工程伦理理念与化工设计课程内容的融合,旨在增强学生的工程伦理意识与职业道德观念,培养具有可持续发展理念和工程伦理素养的高素质化工人才。     

振荡操作制备双峰聚乙烯的模拟

以流化床乙烯气相聚合工艺为例,提出了通过控制聚合反应条件的振荡操作,在单一反应器内实现制备双峰分子量分布聚乙烯的新工艺.通过模拟计算,分别考察了氢气、乙烯、共聚单体进料速率和反应温度的振荡操作对聚乙烯分子量分布的影响.计算结果表明,采取振荡操作后,聚乙烯树脂的分子量分布呈明显的双峰分布,表明在一个反应器里通过控制反应条件的振荡来制备双峰聚乙烯是可行的,而控制氢气进料速率的振荡操作是制备双峰聚乙烯最为有效的方法.     

工业流化床乙烯共聚合生产过程中牌号切换的最优化研究

A model of grade transition is presented for a commercialized fluidized bed gas-phase polyethylene production process.The quantity of off-specification product and the time of grade transition can be minimized by the optimization of operating variables,such as polymerization temperature,the ratio of hydrogen to ethylene,the ratio of co-monomer to ethylene,feed rate of catalyst,and bed level.A new performance index,the ratio of melt flow(MFR),is included in the objective function,for restraining the sharp adjustment of operation variables and narrowing the distribution of molecular weight of the resion.It is recommended that catalyst feed rate and bed level are decreased in order to reduce the grade transition time and the quantity of off-specification product.This optimization problem is solved by an algorithm of sequential quadratic programming (SQP) in MATLAB. There is considerable difference between the forward transition and reverse transition of grade with regard to the operating variables due to the non-linearity of the system.The grade transition model is extended to a high space time yield(STY)Process with the so-called condensed model operation.In the end,an optimization strategy for multi-product transition is proposed with two-level optimization of the objective function J(x,u) on the the basis of the optimal grade transition model.A sequential transition of six commercial polyethylene grades in illustrated for an optimal multi-product operation.     

连续聚合过程中牌号调度策略的研究

基于工厂聚乙烯树脂牌号切换产生废料量的设计值,建立了废料量的预测模型,其误差仅为１０．４５％（均聚牌号）和５．０７％（共聚牌号）;并提出了以赢利与否为依据的牌号切换判断模型。     

PVC的超临界水降解

煅烧法处理废旧 PVC由于产生的氯气腐蚀煅烧炉内壁而不能推广 ,同样 ,填埋法由于产生邻苯二甲酸盐和像铅、锡、钙等重金属离子渗入土壤污染环境而遭限制。超临界水降解处理废旧 PVC显示了很好的潜力。在 2 0 cm3 的高压反应器中 ,PVC颗粒和水分别为 0 .1g和 10 g,在 40 0℃到 60 0℃之间 ,反应 1小时 ,然后冷却至室温 ,取样 GC- MS分析。在 40 0℃、370 atm反应 ,得到的液相产品中有苯、酚、乙酸等 ,气相产品中有丁烷、丙烷和戊烷等。在 60 0℃、60 0 atm反应 ,液相产品中有苯、酚、萘等 ,气相产品中有丁烷、丙烷和戊烷等。氯原子以氯…