Evaluating the Criteria affecting Methane Drainage in Underground Coal Mines Using Interpretive Structural Modeling

The Coal Mine Methane (CMM) process involves: exploration, extraction and drainage of methane gas in underground mining during extraction process. Various factors affect the CMM operation efficiency. Investigating the relationship between these factors and their effect on the process of CMM is very important which has been less attractive to researchers so far. In this research, the effective criteria on the efficiency of CMM were identified using previous studies and expert opinions. Then, the criteria were classified in different levels using the Interpretative Structural Modeling (ISM) method. Then, the underlying relationships between the variables were determined using the experience and practical knowledge of the experts. Finally, a multi-level structural model was created. The results of this study indicated that the coal rank, geomechanical parameters and technical specifications of drilling holes of gas drainage are in the first level with the maximum impact on the process of CMM of underground coal mines. The capital and operational costs related to the CMM process are also at the fifth level of the model and have the least effect on CMM operation. Eventually, by charting the “Matrice d’Impacts Croises-Multiplication Appliqúe an Classment” (MICMAC) and its review, the categorization was done for each criterion based on the degree of influence and dependency. The results of this research can be used for management purposes and methane optimization of underground coal mines.