Study Of A New Type Of Slime Hydroseparator

In the process of coal preparation,the classification equipments exit randomicity,resulting in some coarse coal into flotation;but the effect of flotation on the separation of coarse coal is weak,resulting in a waste of valuable resources. Therefore, according to the working characteristics of the teetered bed separator,applying the principle of teetered settling,a new type of slime hydroseparator with water jumping reflection device was developed and designed with specification for ?=200mm,H=430mm,and the working principle and characteristics of it were elaborated,applying it to the flotation tailings reconcentration and coarse slime separation.Effect of the rinse water content and feed concentration on the separation efficiency were tested in the flotation tailings reconcentration. Results show,when the rinse water content is 0.44 m3·h-1,it can recollect +0.125 mm low ash middings coal from the coal flotation tailings with yield of 23.64% and ash of 28.48%.With the decreasing of the particle size,the yield of fine particle into the overflow increase,particularly-0.125 mm fine-grained level enters the overflow about the amount of 70%,which shows that the new type of slime hydroseparator does not only have separation effect,but also plays a certain role in classification. But too high rinse water will be not good for separation. When the better feeding concentration of 180-240g·L-1,the ash of every particle size in underflow was more than 68%, and loss amount of clean coal in underflow decreased,which contributes to the recovery of clean coal.Effect of the rinse water content and feeding tube insertion depth and narrow particle size feeding and middleflow channel gap size on the separation efficiency were tested in the coarse slime separation. Results show,the separation equipment have a effect on coarse slime,and it can obtain ash < 11% of 0.25-3mm coal.And coarser in particle,the smaller in ash. Deeper in feeding tube insertion depth,the better in separation,and the separator adopts 167 mm in feeding tube insertion depth.Larger in feeding quantity,worse in separation,selecting 3.5-4.5 m3·h-1 better. Smaller in middleflow channel gap,more serious in loss of clean coal in underflow, worse in separation precision. But with increasing of middleflow channel gap, the loss of clean coal will increase in middleflow,bad for the separation.So 5mm was adopted for middleflow channel gap.Separator flow field simulation results show that under the action of reflecting hydraulic jumping,feeding forms with a certain speed to upward reversal flow,providing the first upward water flow.And rinse water provides the second upward water flow. The rinse water has a great influence on the flow field distribution in the under cone,and a small influence on the overflow column. Increasing the top water,big top water will enlarge the disturbance of the flow field,and it is not good for particle separation. Increasing the feeding rate will increase the disorder of the flow field and speed up the discharge rate of the material,and reduce the residence time of the particles in the separator,which is not conducive to the settlement of particles. The simulation result of top water quantity and the feed rate are consistent with the experimental results. It is necessary to select appropriate top water quantity and feeding rate.In general, the new separator can get three different quality products.It has good separation efficiency in the flotation tailings reconcentration,and can improve the coarse flotation tailings coal ash. The new separator is a kind of effective flotation tailings reconcentration equipment,and it has some adaptability for different property coal.