The main equipment of the pulverized coal preparation system is the coal mill vertical mill.If pulverized coal is to be produced, the coal mill equipment is first required, which is the main equipment of the pulverized coal preparation system.
At present, the commonly used coal grinding equipment in the industry include vertical mill and European mill (Raymond Mill upgraded products), among them, the European mill system is applicable to small and medium-sized pulverized coal production line projects, with a unit hour of 3-50 tons; The vertical mill system is applicable to medium and large-scale pulverized coal production line projects, with a unit hour of 6-100 tons.
In view of the particularity of pulverized coal processing, the vertical coal mill is different from the ordinary vertical coal mill. The system adopts a five-level explosion-proof device to ensure the safety of production.At the same time, vertical coal mill system drying and pulverizing two in one, can realize drying while grinding, the system has stable operation, low noise, energy conservation and environmental protection.
What is the working principle of the vertical coal mill?
The raw coal from the raw coal storage yard falls onto the high angle belt conveyor or hoist after passing through the lattice screen, after the iron is removed by the electromagnetic iron remover, the belt conveyor or hoist sends the raw coal to the raw coal bunker for storage.
After the pulverizing system has been started, open the rod valve at the bottom of the raw coal bunker, start the sealed metering belt coal feeder, and the raw coal enters the vertical coal mill for drying and grinding.
The hot air or waste gas from the hot blast stove enters the vertical coal mill under the suction of the system fan, after full heat exchange with the ground raw coal in the mill, the pulverized coal is picked up and sorted at the separator. The coarse pulverized coal with unqualified fineness falls back to the grinding plate for grinding. The qualified pulverized coal enters the explosion-proof air box pulse dust collector with the air flow and is collected and discharged into the pulverized coal bunker through the dividing wheel. Sundries in raw coal, such as some coal gangues and metal blocks, are excluded from the mill through the air ring and slag spitting port.
The whole process is equipped with a CO-O2 online analysis system. When processing coal with high volatile content, nitrogen protection, CO2 automatic fire extinguishing system and other safety measures can be set.
