振荡操作制备双峰聚乙烯的模拟

Simulation of bimodal polyethylene products by operation parameters oscillation

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.

For the industrial fluidized bed gas-phase polyethylene production process, a new technology that produces bimodal polyethylene in a single reactor by oscillating the operation parameters was proposed. The change of molecular weight distribution during oscillation of operation parameters, including hydrogen flow rate, ethylene flow rate, comonomer flow rate and reaction temperature was investigated by simulation. After oscillating the operation parameters, the bimodal molecular weight distribution （MWD） of polyethylene was generated. The simulation results show that it is feasible to produce bimodal polyethylene in a single reactor by oscillating the operation parameters. The simulation result also shows that oscillating hydrogen flow rate is the most effective method to produce bimodal polyethylene.