The Coal Powder Mill is a medium-speed roller-type coal mill, powered by a 450kW electric motor. After passing through three-stage reducers, the output speed is 26.5 rpm. The three grinding rolls on the grinding disc rotate with the disc, grinding the raw coal that falls into the disc from the coal chute; the coal powder, after grinding, is ejected tangentially from the disc and blown into the separator by a single wind; in the separator, coarse powder is separated and returned to the disc for re-grinding, while the qualified fine powder is carried out of the separator and sent to the boiler for combustion. The grinding force for the coal powder is provided by 18 compressed springs at the top, with the pressure and pressure adjustment coming from an external loading device. The single wind enters the wind chamber and flows through the nozzle into the mill, serving to dry the raw coal and transport the ground coal powder. The velocity of the single wind through the nozzle determines the coal powder that is blown into the separator; heavier stones, pyrites, iron pieces, etc., that cannot be blown up fall through the nozzle into the single wind chamber and are scraped into the slag box by a scraper, to be cleared manually on a regular basis. The grinding rolls are located between the grinding disc and the lower pressure ring, with an inclination angle of 12°, and are positioned by the lower pressure ring. The grinding rolls are components for grinding coal powder, with their roller bodies made of the same material as the disc lining, ensuring their service life and matching replacement with the lining. During operation, the roller bodies experience unilateral wear; once the wear reaches a certain degree, they should be flipped to utilize the material properly.

How much do you know about the working process of a coal mill atomizer?

Operation of the coal powder atomizing equipment: As the piston assembly moves forward within the pump cylinder, the liquid in front of the piston pushes the piston diaphragm and bracket backward, pressing against the flat surface, preventing backflow. The liquid is then forced through the discharge ring and into the air chamber, where it is ejected through the atomizing nozzle. When the piston assembly moves backward within the pump cylinder, the piston diaphragm and bracket move forward, creating a space between the flat surface and the bracket. Liquid flows through the diaphragm bracket and the triangular support body, entering the front of the piston assembly through a front hole in the flat plate. At this point, suction of liquid occurs. The pressure regulating valve can adjust the spray pressure. When the liquid pressure exceeds the adjusted spring pressure, the liquid pushes open the valve and flows back into the pump cylinder at the rear of the piston assembly through the conduit. The pressure regulating valve is equipped with a pressure relief valve at the bottom, which can be used to release the pressure on the valve body exerted by the spring, allowing a large amount of pressure liquid to return through the return pipe, reducing the pressure in the pressure system to below 5 kg/cm². The pressure indicator device displays the working pressure within the pressure system during operation.

The coal pulverizer first grinds the coal into powder, then further pulverizes it into standardized coal powder, which is then sent into the combustion chamber for efficient combustion to achieve energy-saving purposes. It is driven electrically via a reduction unit and a vertically arranged main shaft that rotates the grinding disc or ring. Raw coal enters the surface of the two sets of counter-rotating grinding components through a feed pipe, where it is compressed and ground under pressure, becoming coal powder. The ground coal powder rotates with the grinding components, being propelled to the top of the air ring by centrifugal force and the continuous pushing of coal and coal powder being ground. The hot air, after being streamlined through a wind ring equipped with even-flow guide vanes, enters the annular drying space at the corresponding wind speed to dry the coal powder and is carried up to the upper coal powder separator. Unqualified coarse coal powder is separated in the separator and returned to the grinding area for re-grinding, while qualified coal powder is carried out of the mill by a drying agent and enters the primary air duct, directly passing through the burner into the combustion chamber to participate in the combustion. The fuel is coal, which serves as a key heat source for various industrial furnaces. The coal pulverizer is a combined mechanical unit of hammer-milling and centrifugal air delivery, used for粉碎 coal lumps and directly spraying coal powder into combustion chambers for burning in various radiant furnaces, boilers, drying kilns, and smelting furnaces. It is available for factories, mines, and institutions as a配套 for various furnaces.

The coal pulverizer transforms coal into 80-120 mesh particles through a series of crushing processes, which are then suspended and combusted in the furnace at a pressure of over 130 mm water column, achieving complete combustion and contributing to energy conservation efforts. Common types include flat disk mills, bowl mills, E-type mills, and roller mills. They operate at speeds ranging from 500 to 1500 RPM and come in various types. Their common feature is that the crushing components consist of two sets of opposing grinding bodies. Coal pieces are crushed between these grinding bodies through compression and grinding. Additionally, the hot air introduced into the coal pulverizer dries the coal and transports the coal powder to the separator at the top of the grinding area. After separation, coal powder of the corresponding particle size is carried out of the mill with the air flow, while the coarse particles are returned to the grinding area for further grinding.