METHOD AND SYSTEM FOR PRE-COMBUSTION FUEL PULVERIZING Russian patent published in 2003 - IPC

FIELD: solid-fuel burning boiler units of power stations; heating steam and hot-water boilers. SUBSTANCE: method includes pre-crushing of solid fuel to particle size of below 5 mm followed by its pulverizing and conveying pulverized fuel in a gas flow to burners. Pulverization is made in oxidizing medium by dry mechanical destruction in the field of centrifugal forces to particle size of 6-15 mcm due to interaction with blades disposed on concentrically mounted disks rotating in opposite directions; prior to fuel combustion steam is injected in dust-gas flow in the amount of 1.0-3.0 mass percent. Fuel pulverizing system has bin, mill, fan whose inlet pipe is joined with air inlet and/or furnace-gas outlet pipeline, and burners communicating through dust line with mill. In addition system has jet-type rotary mill incorporating several concentrically mounted rotors made in the form of disks with blades forming nozzle channels and rotating in opposite directions. Burners are also connected to steam pipeline. Proposed system provides for pulverizing solid fuel to fractional composition optimal for combustion process at minimal cost. EFFECT: simplified design, enhanced efficiency of pulverized-fuel combustion and reliability of system. 3 cl, 1 dwg