Abstract: According to the enironment pollation problem caused by the coal dustaccunulation resulted from closed producion environment during the productionprocess in Tunian Coal Preparation Plan,based on the analysis on the coal dust danger of the coal preparation plant.accoding to the sie cal dust sourcesoccured mod diferent cal paricle grade and sSite coal dust mass density analysis,the folowing measures were conducted individual y. According to the link features of the primary coal dust and secondary coal dustoccured.cosures were made to the vibration screen.coal crusher.coalfeeder and stage chute and the bag dustc llctors were applied to the dust clcion. As for the key coal transer links and the secondar high dust links adtonal dust colection and water spraying mode were appiedto the dust collction.Before and aiter the reonstruction.the dection resuts of the cal dust mass densty showed that withthe combined role of the bag dust collctor and te dust cllecion and water spraying system,ywhen the system was nmormally operated,the coal dust mas density would be reduced by abou 3 mg / ms. Afier an operaton stopped temporarily in the equipment restarting pro.ess.he average coal dust densty would be reduced by about mg / n3.Thus the dust cotrolefect was obious and the site operation environment was effectively improved.