| As the degree of coal mining is more and more deep,and the strengthening of mechanized degree,the coal slime water settling of fine particle is an indispensable link in coal slime water treatment process,most of the current coal preparation plant adopting settlement of thickener for coal slurry concentration and the thickener covers an area of big,capacity low,and needs a lot of drugs.In order to improve the above situation,combined with the characteristics of particle sedimentation,design and manufacture of a new type of coal slime fine particle sedimentation classification equipment,and detailed description of the new type of coal slime fine particle sedimentation classification equipment and work flow and equipment supporting institutions and packaging production.Firstly,the preparation and selection of samples before the test were carried out.Considering the influence of shape coefficient on sedimentation classification,quartz was finally selected as the raw material for the test,and the particle size of 0.5-0.25mm,0.25-0.125mm,0.125-0.045mm and-0.045mm were obtained,and the natural sedimentation test was carried out for them respectively.The laser particle size analyzer was used for analysis to explore the speed of particle settling.It was found that the particle settling was slow in the natural state when the particle was-0.125mm.The test material was determined as-0.125mm whole particle size.Secondly,the force of particles in the settlement classifier is analyzed,and the basic parameters such as drum radius,upper and lower rectifying groove height ratio,bottom flow diameter and skirt inclination Angle are preliminarily determined based on the force and the principle of settlement classification.FLUENT was used to simulate different structural parameters of the equipment and explore the influence of different structural parameters on the flow field inside the equipment.Finally,a set of optimal structural parameters were determined,including the drum radius of 400mm,the height ratio of upper and lower rectifying groove of 1.5:1,the bottom port diameter of 5mm,and the skirt inclination Angle of 110°.Then the classification effect and processing capacity of the sedimentation equipment for fine particles of coal slime in the supergravity field were investigated.It was found that the larger the overflow ring was,the higher the handling capacity was.When the overflow ring is the same,the handling capacity increases linearly with the increase of rotational speed.When the overflow radius is 340mm,the overflow flow is:y=0.03 1x+1.29,and the bottom flow is:y=0.0005x+0.75.When the overflow radius is 200mm,the overflow flow is:y=0.0007x+0.56,and the bottom flow is:y=0.0003x+0.42.Under the same feeding concentration,coarse particles in the bottom flow and fine particles in the overflow increase with the increase of drum rotation speed,indicating that the improvement of rotation speed can enhance the classification effect,but the sedimentation effect decreases and the sedimentation rate increases.At the same drum speed,with the increase of the feed concentration,the fine particles in the bottom flow increase,and the coarse particles in the overflow increase,indicating that the increase of the feed concentration is not conducive to the improvement of the classification effect,but is conducive to the settlement of fine particles.At the same feeding concentration and the same drum speed,the overflow radius increases and the classification effect decreases,indicating that with the increase of the overflow radius,the processing capacity increases,leading to the particle classification before the completion of stratification in the drum,which reduces the classification effect.Under different overflow radius,drum speed and feeding concentration,it is found that the actual classification particle size is less than 0.04mm,indicating that the classification equipment has a good effect on the settlement classification of ultra-fine coal slime.Figure[72]Table[25]Reference[60]... |
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