The Wet Precise Classification Technology Research Of Spherical Polymer Particles

Exchange resin and adsorption resin have extensive and important applications in modern industrial such as medicine, food, chemical and water treatment etc. But this type of spherical resin products made in China have a wide particle size distribution range,a poor uniformity and a lower product quality,which affect its function and application.The key to solve this problem is precise classification of spherical resin,but toward the classification accuracy of this kind of low-density material, the existing domestic classification equipment absolutely can not meet the product requirements of particle size and uniformity.Aiming at the exist classification problem of spherical polymer particles, On the basis of comprehensive analysis to classification theory,wet classification technology research status and progress,based on new type multilevel hydraulic suspension overflow apparatus made specially by subject,The paper conduct comprehensive experiment evaluation of its classification effect,and analysis the influence relationship between separation particles size,classification efficiency and operation parameter. Experimental studies have shown that for the exchange resin spherical particles of LX-1000EP(D) type,with a particles size range of 55 to 350μm,with a density fluctuations range of 1.177to 1.072 g/cm3,when using new type multilevel hydraulic suspension overflow apparatus to rate,at a separation particles size of one hundred thirty fiveμm,the achieved classification effect is a fine particles recycling rate of 91.2%,a crude particles recycling rate of 92.1％,a composite classification efficiency of 83.3%,a overflow product classification accuracy of d90/d10=1.83,a settlement product classification accuracy of d90/d10=1.73. overflow product and settlement product are very outstanding.The paper also adopt laser scattering image point measurement method to analysis settling velocity of different size polymer spherical particles in water and particles size test,and we found that the particles density of exchange resin and adsorption resin is not homogeneous,but increasing with the decreasing of particle size,that about 10% density fluctuation.This is mainly because the uneven of stoma size and stoma rate forming in the synthesis process cause,and stoma size and stoma rate of exchange resin and adsorption resin significantly affect its application performance. Therefore, this measurement method provided a important test analysis mean for controlling product quality in polymer spherical resin synthesis. The relationship between particle density pp,particle settling velocity u and particle diameter Dp is:pp= p+18μu/(gD2p).Furthermore,the paper using FLUENT fluid analysis software,simulated the internal flow field distribution circumstance of suspension overflow apparatus,and obtained velocity vector distribution figure and velocity distribution figure.The simulation consequence show that through steady flow calculation, in the interior of suspension overflow apparatus, velocity distribution is very uniform, and large swirl does not exist, reasonable velocity gradient, distribution reasonable velocity magnitude.This numerical analysis simulation result also provided design basis for optimizing hydraulic suspension overflow apparatus structure and further improving classification performance.