Vertical mill production issues to consider

(A) must be kept vertical mill rollers and the material layer disc produced sufficient grinding pressure, so that the material being compacted and crushed. That pressure grinding roller pressure, it is contacted with the material grindability, moisture, yield requirements, wind speed and vertical grinding mill type and size and other factors. Grindability, low moisture materials, and low production requirements,the pressure of the roller can be smaller. Roll pressure dependent hydraulic system pressure for pressurizing device (rod) is applied and the weight roller is generated and can be adjusted during operation. In addition, the material layer on the disc must have sufficient stability and to maintain a certain height of the material layer. As shown in Figure, the bulk material by first rolling mill rolls, roll pressure focused on the role of large pieces of particulate material, or when the pressure increases the compressive strength of the roll over of materials, namely crushed material. other larger Materials  particles are then continuously rolling so that the particle size decreases until the fine particles are extruded disc overflow.

(B) vertical mill grinding efficiency not only with the roll pressure, but also with the height of material layer. There are plenty of contact surfaces in contact with the material must be maintained between the roller and the disc. And materials to maintain a certain height, so that the material to withstand the constant pressure roller. For material to form a stable layer of material more difficult, we must take measures to control. As for the feeding of dry material or more powder material on the disc easily flow, the material layer is unstable, so need to take water spray to stabilize the material layer. Also can automatically adjust roller pressure to adapt to erratic changes in the material layer.
(C) vertical roller mill is a grinding and drying winds swept mill, the large body cavity, allows greater airflow, so that the mill of fine particulate material in suspension, due to vertical mill grinding the raw material or coal, the higher its drying efficiency. Vertical mill and supporting the use of dry-process cement kilns, can take advantage of the preheater exhaust into the hot exhaust gases through drying mill in materials. Usually vertical mill can dry up to l5% moisture of raw materials.
(D) Grinding and separator is as a whole in the vertical mill . When the material particles leaving the disc edge, is a high-speed air stream blowing collar rises, the fine particulate material is brought to a separator, finer particles are selected, coarse particles from the gas stream settle to the disc , there are some coarse particles at a reduced speed into the classification zone, may be pulling away from the rotor blades hit and fell onto the disc, Forming a grinding cycle.