The Method of Controlling Air Volume in Vertical Grinding Mill Processing Coal Gangue
Coal gangue is the solid waste produced by coal mining and washing. It is the main waste of coal mining and is regarded as harmful substances and harmful gases. In the mining of coal gangue, the use of grinding equipment is indispensable. In the development strategy of mills, we should adhere to the principle of clean and environmentally friendly resource saving, recycling and turning waste into available resources.
The inorganic components of coal gangue are mainly oxides of silicon, aluminum, calcium, magnesium, iron and some rare metals. The percentage of the chemical composition of SiO 2 is 52-65. Al2O3 ranges from 16 to 36 and Fe2O3 from 2.28 to 14.63. CaO ranged from 0.42 to 2.32. MgO ranges from 0.44 to 2.41. Titanium dioxide is 0.90-4. P2O5 ranges from 0.007 to 0.24. K2O+Na2O ranges from 1.45 to 3.9. V2O5 ranges from 0.008 to 0.03. The main useful minerals in high sulfur gangue are pyrite and coal. The relative density difference between pure pyrite and gangue is 2-2.3, while the relative density difference between paragenetic pyrite and gangue is 0.5-1.
Vertical grinding mill is superfine powder equipment specializing in the production of non-flammable, explosive and brittle materials with Mohs hardness less than 6 grades. When customers choose grinding equipment, it is necessary to clarify their grinding requirements and the size of finished products according to the actual production needs. Usually, it starts from two aspects, one is material hardness, the other is the size of finished materials. High hardness materials can be selected as superfine powder. Fine vertical mill can provide perfect mill equipment according to customers'needs. For the demand of Ultra-fine Coal Gangue powder, we can use high-quality coal grinding mill.
In the process of vertical grinding mill production, it is necessary to regularly adjust the fineness of air volume. In order to meet the needs of production, it is necessary to master some common knowledge of grinder conditioning, such as the size of the diaphragm determines the particle residence time in the grinding chamber. The bigger the diameter of the separator ring, the shorter the residence time of particles, the bigger the particle size of crushed products, the higher the output, and vice versa. The air flow can be controlled by adjusting the butterfly valve at the outlet of the mill. The particle size of vertical grinding mill increases with the increase of air volume, and vice versa. The quality and purity of the product can be improved by adjusting the size of the discharging hole of the discharging device. The clearance between the grading impeller and the diaphragm ring decreases, the clearance between the product becomes finer and the product becomes thicker.