Fine Particle Classification Of Three-product Cyclone Classification Screen

In recent years, high ash of fine mud influence on flotation has received thewidespread attention as its quantity increase and quality reduction. The technology fordesliming process and equipment before flotation has become a hot issue.Three-product cyclone classification screen has achieved some fruitful results in thetheoretical research and industrial application as a new type of high efficiency finecoal classification equipment. The purpose of this paper is to ues this equipmentdesliming before flotation and meet the requirements of classification size andimprove the desliming efficiency.Three-product cyclone classification screen can achieve a good grade owes tocyclone grading theory of hydrocyclone. Introducing the screen just has influence onthe fluid boundary layer on the surface of fluid, and cyclone grading is not disturbedin the three-product cyclone classification screen. This paper divides the theory of thethree-product cyclone classification screen into the cyclone classification of theinternal slurry and sieve classification in solid boundary layer. This paper gets theformula of cyclone classification referring to the research achievements ofhydrocyclone, and gets the formula of screen classification based on the investigationof particle movement along the wall.In order to make the slimes (-0.045mm) concentrated in the overflow and screenunderflow, the experiment began with exploring different sieves which have a greatinfluence on the size consist. Both polyurethane sieve and wire sieve are the objects ofstudy, these sieves which are made up of different materials have different open area.In the experiment, changing different structure parameters and operate parameters toget the good desliming effect. Research shows that polyurethane sieve is not suitablefor three-product cyclone classification screen. In the exploration experiment of wiresieve, found that when sieve openings0.188mm and the sieve length115mm, theefficiency of desliming can achieve95.12%,95%of the particle size in the overflowand screen underflow below0.1mm. The experimental repeatability was high, manyexperiments were able to achieve the ideal desliming effect.The researth of this paper can expand the function of three-product cycloneclassification screen, it provides that this equipment can achieve good deslimingeffect before floatation. Research finding in this paper lay the foundation forthree-product cyclone classification screen in fine particle classification field.