Study On Green Mining Technologies And Environmental Impact Assessment Of Open Coal Mining

In recent years,the output and proportion of coal mining has been increased year by year in China,and the total output has been increased from 5%to 18.6%.With the development of open coal mining to the direction of production and technology and equipment large-scale,which further accelerates the destruction of ecological environment,the ecological environment in open coal mining area is deteriorating rapidly,and its influence range is also expanding.It get us to adopt green mining technology in the process of open coal mining to reduce the damage to the ecological environment.Based on the analysis the degree and the way of the influence to ecological environment,gas environment,water environment and solid environment in the process of open coal mining,put forward the support system of green mining technology,including the technology of land consolidation and recovery,gas and water environmental protection technology,environmental protection within the steep slope mining and stripping technology.The effect of adding corn stalk biochar and rice straw biochar on soil improvement of reclaimed land was verified by experimental research,The results showed that medium and high amount of biochar can significantly improve soil fertility,and the effect of rice straw biochar on the soil improvement of open coal mine drainage field is better than that of corn stalk biochar.In order to reveal the influence of section shape on the slope stability of open pit mine,the stability change law of the nonlinear slope including original design slope and different outer convexity was obtained through simplified Bishop method and numerical simulation calculation based on strength reduction method.put forward the concept,connotation,classification and reasonable matching relation of green mining process system in opencast coal mine,According to the classification types of open coal fields in China,the characteristics and applicable conditions of the green mining technology system,the optimization model of opencast coal mining technology selection is constructed.Based on the concept of green mining of open coal mine,this paper puts forward the concept,connotation and function of "greenness",which based on the green mining technology of open coal mine.Based on the analysis of the impact of open coal mining on the environment,a three-level evaluation index system was established to evaluate the greenness of open-pit coal mines."Green factor" is introduced as the evaluation index value at all levels,and the three-level evaluation index is determined by using the fuzzy membership function..The paper divided the evaluation index of "greenness" into five grades.The analytic hierarchy process(ahp)is used to determine the weight of evaluation indexes.The extension matter-element model and fuzzy comprehensive evaluation model are proposed as the mathematic evaluation model of green degree evaluation of opencast coal mining,and the extension matter-element evaluation model,classical domain and joint domain are established to describe.The extension element evaluation model is used to obtain:I=2,then the grade of greenness of the open-pit mine is grade II,which is consistent with the calculation results of the fuzzy comprehensive evaluation model.