Research On The Rule Of Dust Distribution In Fully-mechanized Coal Face

Fully-mechanized coal face is the biggest dust source in the coal mine.The concentration of dust,which is often ten or ever hundreds of times over the national hygienic standard,seriously endangers the health or even life of miners.The control of dust in fully-mechanized working face has become one of the biggest difficulties in coal mine nowadays.A lot of designing for dust prevention system and the layout of the collect-dust facilities can not achieve the best results or can not be used on the key point, the problem is the indistinct of dust distribution.So researching the dust distribution in the Fully-mechanized coalface has great significance for develop effective dust prevent and control programme.This paper set out from the real difficult in the fully-mechanized coal face dust prevention, the high level of dust distribution,the indistinct of dust distribution,focuses on 1303 coal face in Zhaozhuang mine,the method of on-site investigation,date measurement, theoretical analysisand and numerical simulation have been adopted in order to obtain the airflow distribution rule and the dust distribution rule.Based on the research conclusions, combining with the field situation,the author provides some suggestion to prevent and remove the dust of fully-mechanized coalface.The main conclusions of the paper are showed as following:(1) Airflow into the face,wind speed in the space of shearer is greater than it in the sidewalk space,in the face of Shearer position than other parts,in the all coal face.(2) Research the distribution of dust that contained in the drum and produced in cutting and moving the Hydraulic Shield Support,get the dust distribution in the coal face.(3) The dust contained in the drum and the dust produced in cutting,mainly move along the wall,and descent little by little,the majority of dust was trapped on the coal wall,on the floor and the top face,then the trajector terminate.The coal dust's spread speed is limited,only a small number of dust spread to the sidewalk space,from drummed out the face with the airflow.(4) In the coal face,concentration of dust gradual decrease along the way,and the concentration in the space of shearer is greater than the sidewalk space.In the section of space,the concentration of dust is greater near the floor,when cutting coal against the wind, from the face,the concentration of dust is greater near the roof,when cutting coal along the wind.(5) In the fully-mechanized coal face when Shearer cutting the coal body,the mass middle diameter are 19μm～43μm,and less than 7.1μm of respirable dust of the total of 8.5%to 22%.Classify the dust that produce from cutting the coal body in the fully-mechanized coal face,by particle size,analysis:the dust in the size section of 0μm～40μm,it's mass percentage is increase gradually along the way,the dust in the size section of 40μm～100μm,it's mass percentage is decrease gradually along the way;the dust in the size section of 0μm～10μm,it's concentration is keep fixed along the way, the dust in the size section of 10μm～80μm,it's concentration is increase first and decrease later,the dust in the size section of 80μm～100μm,it's concentration is decrease along the way.The innovation of this paper is showed as following:Classify the dust that produce from cutting the coal body in the fully-mechanized coal face,by particle size,analysis:the dust in the size section of 0μm～40μm,it's mass percentage increase gradually along the way,the dust in the size section of 40μm～100μm,it's mass percentage decrease gradually along the way;the dust in the size section of 0μm～10μm,it's concentration is keep fixed along the way,the dust in the size section of 10μm～80μm,it's concentration increase first and decrease later,the dust in the size section of 80μm～100μm,it's concentration decrease along the way.