摘要：针对目前大宗正压开放式气力输送粉体过程中出现的料位低于临界料位值后会出现大面积腾涌、输送效率大幅度下降的问题,以山东省莒县某大型水泥钢板仓为研究对象,通过相似理论模拟设计开发开放式气力输送仓泵,并据此建立开放式气力输送系统;在该系统上以水泥粉体为输送物料,压缩空气为输送动力进行实验研究。结果表明:正压开放式气力输送过程中,固体质量流率、压力损失随料位的减小出现先增大后减小的趋势,拐点处对应的料位为临界料位。同时,研究发现临界料位随气体表观速度与平均固气质量比的增大呈减小趋势。

关键词：正压开放；气力输送；临界料位；流动参数

Abstract：In order to avoid large area slugging of solids particles and conveying efficiency decreasing when the solid level arrived at critical level value, a open type pneumatic conveying system was designed and built up according to the theory of similarity and the large scale cement steel silo structure of a cement plant which lied in Juxian, Shandong province. In this system, pneumatic conveying experiments were carried out which compressed gas taking along cement powder. The results show that in process of pneumatic conveying, with the decrease of solid level the mass flow ratio and pressure drop increase first and then decrease. The solid level of inflection point on the trend curve is defined as critical solid level. Meanwhile, with increase of gas velocity and the solids loading ratio, the critical solid level decreases。

Keywords: positive pressure open type；pneumatic conveying；critical solid level；flow parameter