高压法LDPE管式反应器的结构优化方法

Structure optimization method for high-pressure LDPE tubular reactor

高压管式反应器是生产低密度聚乙烯(LDPE)和乙烯-醋酸乙烯酯共聚物(EVA)等产品的重要装备。高压聚合反应条件苛刻,高压管式反应器的设计不仅要满足聚合反应工艺要求,还要满足装备的机械强度和疲劳寿命要求。以高压法LDPE管式反应器为研究对象提出了管式反应器结构的两步法优化策略,首先根据超高压容器标准确定反应器的管径比要求,并基于管式反应器的详细模型计算引发剂配方对管式反应器升温速率的影响规律,然后以单位转化率下的年度总费用作为目标函数,采用遗传算法优化得到反应器的管径、分区长度等结构参数。所提出的管式反应器的结构优化方法具有较高的准确性,可为高压法LDPE管式反应器的优化设计和技术改造提供理论指导。

High-pressure tubular reactors are crucial equipment for the production of LDPE(low-density polyethylene)and EVA(ethylene-vinyl acetate copolymer)and other products.Due to the harsh conditions of high-pressure polymerization reactions,the design of high-pressure tubular reactors must not only meet the process requirements of polymerization but also the mechanical strength and fatigue life requirements of the equipment.Taking the high-pressure LDPE tubular reactor as the research object,a two-step optimization strategy for the structure of tubular reactors is proposed.Firstly,the required pipe diameter ratio of the reactor is determined according to the ultra-high pressure vessel standards,and the influence of the initiator formulation on the heating rate of the tubular reactor is calculated based on the detailed model of the tubular reactor.Secondly,the total annual cost per unit conversion is used as the objective function,and genetic algorithms are employed to optimize the structural parameters such as the pipe diameter and length of the partition.The structure optimization method proposed in this paper is highly accurate and will provide theoretical guidance for the optimal design and technical transformation of high-pressure LDPE tubular reactors.