| 摘要 |
FIELD: preparation of solid fuel for burning; thermal power stations working on lower-grade coals. SUBSTANCE: dust concentrator has housing 1 made in the form of symmetrical horizontal polygonal prims with horizontal discharge pipes 3-6 mounted centrally, inlet branch pipe located under housing, coarse dust discharge branch pipes 8-11 arranged in lower portion of housing and baffle plate mounted before other inlet branch pipe located between vertical projection of discharge pipes 3-6 above housing 1. Guide plates 14 used for acceleration of air mixture are also arranged inside housing. From the mill air mixture flows to inlet branch pipe 7 where it is accelerated between plates 14 and strikes against baffle plate 12 where it is crushed. Hot flue gases are fed to housing 1 through other inlet branch pipe. Hot flue gases are mixed with duct escaping from under baffle plate and explode dust particles due to vaporization of moisture contained in particles. Then several impacts against edges of walls of housing 1 occur; as a result, dust is crushed finally and enters coarse dust branch pipes 6-11 connected with furnace burners. Waste drying agent and volatile matter separating from fuel during thermal preparation inside housing 1 escape through discharge pipes 3-6 to burners. Dust has high specific surface due to porosity of particles and uniform granulometric composition, thus ensuring sudden ignition and quick burning-out of dust in furnace which excludes drawing-in of jet into convective shaft and slugging and reduces incomplete burning. EFFECT: enhanced efficiency due to increased service life of mill beaters, facilitated kindling and reduced slugging due to thermomechanical re-crushing and thermal preparation of fuel in dust concentrator. 3 dwg |
