Study On Mechanism And Control Technology Of Blasting Dust In Da NanHu No 2 Open-pit Mine

Now big south lake no.2 of open-pit mine production operation has entered into the firstⅣfire area,at the firstⅣfire area in the process of rock blasting operation steps exist the problem of dust concentration,blasting operation to produce the large amount of dust and pollute the environment seriously affect the subsequent production,in order to make big south lake no.2 pit can be better for production and reduce the pollution on the surrounding environment,Dust generation mechanism of rock step blasting in burning area of Da Nanhu No.2 open-pit mine is studied deeply,and the blasting operation of rock step in burning area is optimized.The blasting numerical simulation of rock step in the burning area of Da Nanhu No.2 open-pit mine was carried out,and the stress and strain neographs of the numerical simulation were analyzed to find out the root cause and main influencing factors of the high dust concentration in the blasting operation of rock step in the burning area of Da Nanhu No.2 open-pit mine.Three representative measurement points were selected on the rock steps in the numerical simulation of the burning area for detailed research on the reasons for the large dust concentration in the rock steps blasting in the burning area of the Da Nanhu No.2 open-pit mine by combining macroscopic and microscopic methods.The parameters of rock step blasting operation in the burning area of Da Nanhu No.2open-pit mine are 6m hole spacing,5m row spacing,0.23kg/m~3unit explosive consumption,continuous charging and single-initiation blasting.Orthogonal experiment is used to optimize the rock step blasting operation in the burning area of Da Nanhu No.2 open-pit mine.It is obtained that the blasting scheme of rock step blasting in the burning area of Da Nanhu No.2 open-pit mine has the minimum dust concentration as follows:hole spacing 7m,row spacing 6m,unit explosive consumption 0.21kg/m~3,interval charging distance 1m and differential difference between rows55ms.The analysis shows that the blasting scheme has the effect of reducing the dust concentration of rock step blasting in the burning area of Da Nanhu No.2 open-pit mine.This paper not only provides a theoretical basis for the optimization of rock step blasting operation in the burning area of No.2 Da Nanhu open-pit mine,but also provides a reference value for the similar situation in other open-pit mines.