气固流化床分布板死区的声发射检测  

Detection of Dead Zone on the Distributor of Gas-Solid Fluidized Bed Based on Acoustic Emission Measurement

作　　者：陈杰勋[1] 曹翌佳[1] 任聪静[1] 王靖岱[1] 阳永荣[1] 

机构地区：[1]浙江大学化学工程与生物工程学系,浙江杭州310027

出　　处：《石油化工》2008年第9期910-914,共5页Petrochemical Technology

基　　金：国家自然科学基金重大项目(20490205);国家高技术研究发展计划资助项目(2007AA04Z182)

摘　　要：在φ250 mm 的流化床中,采用空气-聚乙烯颗粒体系和3种不同结构的气体分布板进行流化实验,通过声发射检测装置采集气体分布板下方不同位置的声信号,分别考察了3种小同结构的气体分布板上流化死区的存在情况与位置分布。实验结果表明,分布板局部的声信号平均能量可以反映对应位置的颗粒活跃程度,定义了颗粒活跃程度指数 R_i,并提出以 R_i=0.6作为流化死区存在的判据。声发射技术能有效地检测流化床分布板上的流化死区,对分布板的设计以及工业生产的故障监控都具有积极的意义。The fluidization experiments were put forth in air-polyethylene system within a 250 mm diameter fluidized bed, using three distributors with different structures. By analyzing acoustic emission （AE） signals received beneath the distributor, the existence and location of dead zone on the distributor were investigated. It was found that the local mean energy of AE signal can represent the particle activity at the related region. The idea of particle activity index （Ri ） and the criterion to identify the dead zone are proposed. When R; 〈 0. 6, the corresponding region can be looked upon as dead zone. The experimental results indicated that AE measurement can detect dead zone on the distributor effectively, which would strongly support both the design of distributor and monitoring of industrial process.

关 键 词：声发射 气固流化床 分布板 死区 聚乙烯颗粒 

分 类 号：TQ051.13[化学工程]