Experimental Study Of Coarse Slime Separating System For Wugou Coal Preparation Plant In The Case Of High Ash Content And High Slurry

In recent years, the content of pulverized coal is more and more high in raw coal in coal preparation plant. In order to improve separation efficiency and adapt to constantly changing quality of raw coal, dense medium coal preparation technique is becoming the prefered technology of newly built coal preparation plant, heavy medium cyclone becomes leading equipment in separating lump coal. At present, our dense medium coal preparation technique mostly adopts preparation of non-desliming and unsized raw coal, equipments keep developing to large-scale. It is against raising the whole grade of coal separation efficiency although this practice simplify the technology. It is difficult to obtain satisfactory separating effect of coarse slime for our conventional gravity separator and flotation device.The coarse slime of WuGou coal preparation plant and the7th coal seam is analysed first in this subject,it has found that the coal quality deteriorate and the content of high ash fine slime increases a lot in the7th coal seam. Under the condition of good coal quality and poor coal quality,the effect of curved screen in WuGou to recycle coarse slime is comparatively analysed,the result indicates that only curved screen cannot satisfy the recovery and ash content of coarse slime.The separation principle and application of the existing several kinds of coarse coal slime separation equipments is then detailed analysed.Combinated with the using practice in other coal preparation plants and WuGou coal quality,the subject obtained that water medium hydrocyclone and spiral separator is not suitable for WuGou coal preparation plant.Through field sampling and detailedly test analyzing,in combination with once using status of slurry heavy medium cyclone in WuGou, this equipment is not recommended.Field sampling to test the performance of teetered bed separator.the result shows that the equipment can get satisfied separation effect and maintain the stability of the equipment work under high density and low density.At the same time,the subject also analysed the using effect in other coal preparation plants,the result demonstrates that teetered bed separator is more adaptable for different coal quality.Lastly,based on the analysis above, according to WuGou coal quality and the existing processing equipments,the subject puts forward to add teetered bed separator on the basis of original technological process.WuGou coal preparation plant can choose whether open the equipment according to the raw coal quality.The process system has more flexibility.