Fan coal mill

Description

Fan mill is the main equipment of direct-fired pulverizing system for lignite-fired boiler in thermal power plant, and it also meets the pulverizing requirements of power boiler in chemical industry and papermaking factory. The fan mill is a kind of high efficiency pulverizing equipment which can simultaneously satisfy with grinding, drying and delivering. The fan mill has been widely used in direct-fired pulverizing system of lignite-fired boilers with its feature of the simple system, low power consumption and metal consumption, easy operation and low noise.

Our company can provide N and S series of 50 specifications products. For the N series it is properly used for grinding lignite and the lignite with moisture of 40-70%, whose maximum output is 200t/h. And for the S series it is properly used for grinding bituminous coal and hard lignite with moisture of less than 40%, whose maximum output is 90t/h.

How the fan mill works? The raw coal is fed into the gas pipeline and is heated by hot gas then is delivered into the mill. When coal and gas enter the mill the coal is distributed along the inner diameter of the impact wheel, and crushed under the attack and friction of the rotating impact wheel, in which the moisture in the coal also is mostly eliminated and dried. The gas and coal pulverized are moving in the volute then they enter the coal pipeline or the separator at the outlet of the mill.

The impact wheel plays a role of grinding and ventilation. The ventilation volume of the fan mill system includes the gas extracted from the boiler combustion chamber, hot air from air preheater, steam evaporated from raw coal and air leakage. The hot air blown into the side mantles from the bear is used as a seal to prevent leaking dust from the gap of the main shaft and body shell.

The fan mill has sturdy impact wheels and reliable double-row bears which can withstand the instantaneous overload therefore it can handle impurity coal, and that cantilever structure designed for wheel is easy to disassemble and be replaced in a short time.