Dense-medium and low-density separation process

Abstract

The invention discloses a dense-medium and low-density separation process applicable to dense-medium and low-density separation which facilitates coal separation, and relates to the technical field of mineral separation (dense-medium coal separation). The dense-medium and low-density separation process comprises the steps that an oversize product obtained by a raw coal classifying screen and screen underflow which does not pass a hydraulic turnover plate enter a desliming screen; an oversize product obtained by the desliming screen and suspension liquid with the density being 1.35g / cm<3>-1.55g / cm<3> are intensively mixed and then enter a two-product dense-medium cyclone to conduct low-density separation; clean coal obtained by the low-intensity separation becomes a clean coal product after passing through a clean coal de-medium and dewatering device; gangue obtained by the low-intensity separation enters the classifying screen after passing through the de-medium and dewatering device, an oversize product becomes a gangue product, and screen underflow is mixed into pulverized raw coal. The dense-medium and low-density separation process has the advantages of reducing the density of the suspension liquid according to the actual production situation, carrying out dense-medium cyclone low-density separation, being beneficial to efficient recycling of media, reducing the consumption of the media, meanwhile, due to the fact that the separated pulverized gangue is mixed into the pulverized raw coal according to the actual situation, stabilizing the homogenization production of the pulverized raw coal, optimizing the control over the calorific value of the pulverized raw coal, and achieving the maximization of production and economic benefits of the pulverized raw coal.

Description

technical field [0001] The invention relates to the technical field of ore dressing (dense medium coal preparation), in particular to a dense medium low density separation process suitable for easy coal separation. Background technique [0002] The dense medium suspension used for coal preparation should not only meet the required suspension density, but also make the suspension have a certain stability, and at the same time, it must have good fluidity (viscosity should not be too high). During the working process of dense medium equipment, if the density of the suspension is higher and the volume concentration of solids in the suspension is higher, the viscosity will be significantly higher and the fluidity will be worse, which is not conducive to the subsequent curved screen, detachment, etc. The smooth de-intermediation of the media sieve and the efficient recovery of the heavy medium by the magnetic separator fundamentally increase the use of magnetite powder entering th...

AI Technical Summary

Problems solved by technology

During the working process of dense medium equipment, if the density of the suspension is higher and the volume concentration of solids in the suspension is higher, the viscosity will be significantly higher and the fluidity will be worse, which is not conducive to the subsequent curved screen, detachment, etc. The smooth de-intermediation of the media sieve and the efficient recovery of the heavy medium by the magnetic separator fundamentally increase the use of magnetite powder entering the system and reduce the recycling rate of magnetite powder in the system, thereby greatly increasing the consumption of media

For coal that is easy to prepare, its intermediate density level (usually 1.5-1.8g / cm 3 Part) content is very small, the production practice shows that when the dense medium equipment is sorting this type of coal, the density of the suspension is adjusted within a certain range, and the clean coal yield hardly changes, but the medium consumption changes significantly, while Coal preparation plants did not reduce medium consumption from the perspective of controlling suspension density

In addition, at present, some coal will be carried in the gangue sorted out by coal preparation plants at home and abroad, and this part of the product will be directly discarded or sold at a low price as gangue products, wasting resources and causing environmental pollution at the same time

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