从噪声到信息:基于声发射监控的聚烯烃流化床反应器新技术（英文）

From noise to information:a new technology of olefin polymerization fluidized bed reactor based on acoustic emission

目的:在全球所有的合成树脂中,聚烯烃的产能位居榜首,在国民经济建设和社会发展中发挥着重要作用。但流化床聚合反应器内的高静电会引起颗粒团聚,一旦传热受阻,颗粒极易熔融结块,甚至导致装置爆聚停车。本研究旨在针对流化床聚合反应过程具有强放热、高静电、变粒径的特点,提出基于声发射技术的多种检测手段和信息提取方法。创新点:针对聚合过程的爆聚结块问题,本研究主要解决了以下难题:(1)流化床内颗粒和结块的原位表征技术缺失,难以检测;(2)颗粒熔融结块过程的在线干预机制不清楚,难以调控;(3)流动传热过程强耦合,反应器放大规律不明,导致反应器难放大等问题。方法:创立声发射信号的多尺度解析方法,通过小波分解和重标极差分析法分类重构将声发射信号分解为微尺度、介尺度和宏尺度信号;提出基于声发射检测的反应器操作优化技术,并通过建模确立流化床聚合反应器的时空产率数学模型。成果:新技术成功应用于"十一五"国家重点建设项目——天津百万吨乙烯工程相配套的年产30万吨气相法聚乙烯流化床反应器的设计建设。并且,新技术已成功应用于14套大型聚烯烃装置的设计或改造,所涉及的聚乙烯产能达263万吨。作者所在团队也因该技术发明获得了2016年度国家技术发明奖二等奖。

The fluidized bed is widely used in many industrial processes because of its vigorous mixing and heat transfer properties. However, when heat transfer is blocked, the particles are easily melted and agglomerated, and even cause the industrial reactor to shut down. From the point of mechanism analysis, the process of explosive agglomeration is a typical meso-scale problem in the fluidized bed, and there is a complex evolution process between particle fluidization and reactor shutdown. Grasping the regulation of meso-scale structure is one of the major challenges faced by chemical engineering. Thus, in this background, the fluidized bed acoustic emission detection technology, agglomeration fault self-repair technology, and a direct scale-up technique of the fluidized bed mathematical model were invented. These technologies have provided strong reliability for stable operation and have been successfully applied in 14 sets of industrial plants.