Affects the safe operation of the fan and system of great. Using the spray, spray and a lining corundum surface abrasion proof measures, can only play a role in certain conditions. A fine collection of ash and dust: after the classification of fine ash has larger specific surface area, the inter particle static power is strong, the adsorption of water is strong, easy to cause the reunion, compaction and the bypass, resulting in decreased collector efficiency; electrostatic precipitator corona wires and anode system of dust collection and filter bag ash blockage caused by dust and ash hopper shed efficiency decreases.

So that the whole classification system operation failure or interruption. In a single point of feeding system feeding stability control: in large volume positive pressure ash storehouse apparent, with changes within the State Library, the feeding quantity to stochastic control, general difficult.

The detection and evaluation standard of performance of vertical roller mill and systems: because the vertical roller mill and technology is a new technology system, the domestic need unified industry management, the establishment of the nature of the industry technology management departments, make relevant standards and norms, the performance of equipment and system of classification for scientific evaluation and standard in order to avoid commercial publicity, unrealistic and vicious competition. There are some technical indicators are not unified standard formulation, such as classifier processing capacity, efficiency of separation, recovery and so on, need to be normalized.