Airflow transportation method for vertical roller mill airflow device of cement raw material slag

Abstract

An airflow transportation method for a vertical roller mill airflow device of cement raw material slag. A millstone top edge is provided with a material barrier ring; a nozzle ring is arranged at an upper part of a lower barrel body of the millstone; both sides of the lower barrel of the millstone are symmetrically preserved with an air intake; a lower port of a feed returning end air intake box is provided with a revert collection cone and an air-lock turnover plate unloading valve; fixed wear scraping plates are uniformly arranged under the millstone; for working, heat flow upraises into the nozzle ring, and a nozzle ring wear-resistant guide vane inclined in a direction adjusts the airflow to rotates at high speed, impacts, shears and overflows a block material extruded into a cake at an external side of the material barrier ring; the moisture of the block material rapidly evaporates and disperses into powder after high temperature; the powder rises to the top of the mill for further classification process; the millstone drives the wear scraping plates fixed below the periphery; coarse particles and metal impurities at the middle and bottom of the lower barrel are scraped into a returning material collection cone; and air-lock turnover plate unloading valve discharges the coarse particles and metal impurities out of the mill.

Description

technical field [0001] The invention relates to a vertical roller mill for cement raw material and slag, in particular to a vertical roller mill airflow device for cement raw material slag and an airflow delivery method thereof. Background technique [0002] Looking at domestic and foreign vertical roller mills, the finished materials are obtained through the airflow dispersion, drying and pneumatic conveying of the airflow conveying device. The wear-resistant guide vanes of the nozzle ring need to have a suitable horizontal angle. The size of the angle It has a great influence on the dispersion of cakes or granules, the drying of the material surface and the effect of powder pneumatic conveying, and the angle changes with the composition of the material, the moisture content of the material and the air velocity. It must pass the vertical roller mill test bench experiment and CFD Only by analysis can it be determined, and most of the current vertical roller mill airflow conv...

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Problems solved by technology

[0002] Looking at domestic and foreign vertical roller mills, the finished materials are obtained through the airflow dispersion, drying and pneumatic conveying of the airflow conveying device. The wear-resistant guide vanes of the nozzle ring need to have a suitable horizontal angle. The size of the angle It has a great influence on the dispersion of cakes or granules, the drying of the material surface and the effect of powder pneumatic conveying, and the angle changes with the composition of the material, the moisture content of the material and the air velocity. It must pass the vertical roller mill test bench experiment and CFD Only by analysis can it be determined, and most of the current vertical roller mill airflow conveying devices have nozzle rings with wear-resistant guide blades whose angles cannot be adjusted, which affects the airflow conveying effect of the vertical roller mill and the long-term stable operation of the equipment; secondly, At present, the equal-width structural design of the wear-resistant guide blades of the nozzle ring makes the front and rear widths of the cross-section consistent, which increases the local resistance loss of the nozzle ring and the inlet resistance loss of the nozzle ring, resulting in an increase in the operating power of the system fan, which is not conducive to energy saving and consumption reduction. macro goals

Moreover, the excessively high flow velocity of the nozzle ring will also cause the wear of the nozzle ring to increase, and the number of downtime maintenance will increase, which is not conducive to ensuring the annual operation rate target of the vertical roller mill; thirdly, although the double air inlet structure is widely used in the industry However, the shape and size of the air inlet vary greatly and the internal flow guide and material guide structure design of the air inlet cannot form a stable pressure difference and a stable air velocity in the inner area of ​​​​the air inlet, so it is impossible to form a stable air flow. field, so that it cannot become a real high-efficiency air delivery device

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