Vertical mills and ball mills are the first things people think of when choosing a milling equipment, but what is the difference between the two, how do we choose? Next, the SBM heavy machine will introduce the difference between the two to everyone!
The efficiency of the vertical roller mill combines grinding, grading and drying (when the material moisture is large). The vertical roller mill uses the material bed grinding principle to grind the material, which is 30% lower than the ball milling system. Therefore, in terms of grinding efficiency, the vertical roller mill is superior to the ball mill. Moreover, the vertical roller mill uses hot air to transport materials, and can control the inlet air temperature when grinding relatively large materials (such as coal, slag, etc.), so that the product reaches the final moisture, and the vertical roller mill can dry the water by 12-15%. The material; even the drying ball mill can only dry the material with 3-4% moisture; this not only saves economic costs, but also saves time cost.
In the case of the same raw material abrasiveness and product particle size, the power consumption of the vertical roller mill can be reduced by 30% to 50% compared to the energy consumption of the ball mill.
Compared with the ball mill, the vertical roller mill process is relatively simple, and the capital investment is small. The vertical roller mill feeds the material directly through the hot gas stream through the separator. This saves the cost of the classifier and the hoist. The dust-containing gas is directly collected into the collector, so the vertical roller mill system has simple process, low failure rate, high operation rate and compact layout. The construction area is 70% of the ball mill, and the construction space is 50-60% of the ball mill; investment The cost is low.
Compared to ball mills, vertical roller mill products have a higher degree of homogenization and higher purity. This is because the time taken for the finished powder to be classified during the vertical roller mill is short, and over-grinding is avoided. In addition, due to the unique working principle of the vertical roller mill, during the operation of the vertical roller mill, no metal is in direct contact with each other, the metal wear is small, and the pollution of the finished material is small. Vertical mill grinding adjusts the separator speed, wind speed and roller pressure to facilitate the convenient adjustment of product fineness. The ball mill is easy to over-grind, the limestone unit wear is generally 4-6 g/ton, and the ball mill is up to 500 g/ton. When white minerals are ground, the effect on whiteness is much smaller than that of ball mills.
The vertical roller mill is soft at work, usually around 80 decibels. The grinding roller is not in direct contact with the grinding disc, and the noise is about 20-25 decibels lower than that of the ball mill. The vertical roller mill adopts integral sealing, and the system operates under negative pressure, with less dust and clean environment.
As a kind of high-efficiency and energy-saving grinding equipment, vertical roller mill is more and more widely used in the new dry process cement production line. In the raw material preparation process, the production capacity of the vertical roller mill has reached 400-600 t / h. From the scale and quantity, it has been confirmed that it will replace the ball mill as the main grinding equipment of the large cement production line. At the same time, due to its excellent performance, vertical roller mills are gradually applied to slag grinding, cement clinker grinding, power plant desulfurization, phosphate rock grinding, manganese ore grinding and many other industries, becoming the preferred milling for energy saving, environmental protection and environmental protection. device.