CAJ | 학술논문

在不同循环流量和固含率条件下,通过1~2个月的操作运行实验,得到了汽-液-固三相循环流化床蒸发器内聚乙烯颗粒的磨损产物,分析了三相流化床的固含率和循环流量等条件对颗粒磨损速率、磨损粉体的直径和多分散度的影响,并探讨了颗粒磨损的机理.结果表明:磨损产物的粒径呈现三峰对数-正态分布,具有混合磨损机理特征;颗粒的磨损速率随固含率的减小和循环流量的增加而增大;较低固含率条件下,循环流量对颗粒的磨损速率影响较大;磨损速率随着运行时间的延长而减小;磨损粉体的粒径随固含率、循环流量、磨损时间的增加而减小;磨损颗粒的多分散度随固含率和循环流量的增加而减小.
재불동순배류량화고함솔조건하,통과1~2개월적조작운행실험,득도료기-액-고삼상순배류화상증발기내취을희과립적마손산물,분석료삼상류화상적고함솔화순배류량등조건대과립마손속솔、마손분체적직경화다분산도적영향,병탐토료과립마손적궤리.결과표명:마손산물적립경정현삼봉대수-정태분포,구유혼합마손궤리특정;과립적마손속솔수고함솔적감소화순배류량적증가이증대;교저고함솔조건하,순배류량대과립적마손속솔영향교대;마손속솔수착운행시간적연장이감소;마손분체적립경수고함솔、순배류량、마손시간적증가이감소;마손과립적다분산도수고함솔화순배류량적증가이감소.
Particle erosion or attrition products were obtained in a fluidized bed evaporator with vapor-liquid-solid flows at different solid holdup and circulating flow rate of liquid phase after one-month to two month’s operations. The particles from erosion were characterized and the effects of key factors such as solid holdup,circulating flow rate of liquid phase on erosion amounts,particle size and polydispersity were analyzed. Possible particle attrition mechanism was discussed. Experimental results indicated that the powder diameter resulting from the particle attrition showed a log-normal distribution with three peaks,indicating a mixture mechanism of particle attrition. Other preliminary results were presented as follows:the attrition rate of solid particles increased with the decrease of solid holdup and the increase of circulating flow rate of liquid phase,and the latter became important at lower solid holdup;the erosion rate decreased with time;the effective diameter of powder resulting from particle attrition decreased with solid holdup,circulating flow rate of liquid phase and time;the polydispersity of powder decreases with solid holdup and circulating flow rate of liquid phase.