The EDEM Simulation And Industrial Research Of A New Type Of Slime Classifier

Classification is an essential mineral processing and the choosing ofequipment is the premise of classification. In this paper, semi-industrialprocessing equipment-the new slime classifier is designed and machined basedon the design concept proposed by our research group. The classifier usesdynamic and static mesh rings which can effectively limit run rough while avoidsieve network congestion.This paper analyzes the mechanism of this new slime classifier andestablishes a simplified model which simulated by EDEM discrete elementanalysis software. The industrial experiment was carried on Tunlan coal slime tostudy the parameters which affect the performance of this new operating device,and to determine the influence of different parameters. The grading effect of thisdevice was evaluated and compared with the classification performance of theon-site grading cyclone.The study by EDEM simulation found that: the particle motion in thisclassifier is very complex; sports ring helps to avoid the clogging of the screen;spiral roller speed is the important factor that impact the classification performance of this new coal slime grader. The classification efficiency wassimulated, which can up to84.05%.The industrial experiment of this slime grader show that the classificationefficiency of classifier reduced with the feed flow rate increased. The screeningefficiency is low when the feeding is larger because the flow of slime is tooquick that a large part of <0.2mm slime discharged from the outlet under theaxial thrust power of spiral blade without screening. The spiral roller speed is animportant factor affecting the performance of this new slime grader in that thegrading efficiency first increases and then decreases along with the improvingspeed. The mismatch rate of fine material increase when the roller screw speedis too high and in this paper the classification efficiency is best when the speedis61rpm (frequency30Hz). The overall amount of fine materials on the screenincrease as feed concentration increases which show low classificationefficiency. A suitable concentration range should be kept according to the actualsituation because the classification efficiency decrease when the concentrationget too high or too low. The particles are easy to bind when the concentration istoo high whereas the throughput of dry material reduces when the concentrationis too low. When this experiment chooses the feed concentration of101.95g/L,the new slime classifier achieves the highest efficiency.The new slime grader has some concentrated effect. Under a certain speed,the low the feed flow rate, the better the concentrate and desliming effect. Under certain operating conditions, the grading performance of this new classificationis better than the site grading cyclone.