| 摘要 |
A solids pulverizing mill for producing fine particles such as coal dust, which includes a housing having a centrally located coal feed chute and enclosing an annular-shaped air port ring containing multiple nozzles located around a rotatable grinding table. Multiple grinding rollers press down and rotate upon the coal on the rotatable grinding table so as to pulverize the coal, which is then entrained by multiple intersecting and strongly interacting air jet streams upwardly from the grinding table through a classifier section to an exit conduit. The air port nozzle ring is fitted with multiple angled flow passages from which adjacent air jet streams intersect and interact strongly with the adjacent streams to product intense turbulence, which prevents undesirable acoustic vibration of the upflowing air/coal material within the mill housing. The centerlines of adjacent air jet nozzles intersect at an included angle of at least 20 DEG and not exceeding 90 DEG , each nozzle has cross-sectional area of 10-50 in.2, and provides nozzle exit air flow velocities of 140-250 ft/sec so as to prevent undesired acoustic resonance vibrations within the pulverizer mill.
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