METHOD OF MAKING PULVERISED COAL Russian patent published in 2013 - IPC C10B57/10 B02C23/34 B02C23/24 B02C21/00 F26B21/10 

FIELD: process engineering.

SUBSTANCE: proposed method comprises the following jobs: heating of drying gas in hot gas generator 26 to preset temperature, feeding said gas to coal mill 20 and feeding raw coal to mill 20. Note here that said mill pulverizes coal. Besides it includes collection of drying gas and coal dust therefrom and feeding said mix to filter 34. Note here that filter 34 separates dried coal dust from drying coal, collects said powder and feeds drying gas from filter to circulation line 34 for return of drying gas to generator 26. Oxygen content in drying gas and its comparison with preset threshold value are defined and estimated. Oxygen content in drying gas is set at grinding cycle. Note here that heated drying gas is fed via mill 20 while raw coal is fed therein. In case preset amount of oxygen in grinding exceeding preset threshold water is injected to heated drying gas prior to its feed into mill 20. Note also that injected water volume is calculated to reduce oxygen content to below preset threshold.

EFFECT: oxygen level reduced to tolerable level, ruled plant damages or switching off of grinding and drying units.

16 cl, 1 dwg