Risk evaluation model and empirical research for CBM development

The high risk of CBM development project restricts the development of CBM industry in China.Therefore,based on the analysis of main risk factor for the CBM development,we established the index system for CBM development risk evaluation.The index system consists of 7 level indicators and 36 secondary indicators.Considering to the disadvantages of determining factor weight by traditional analytic hierarchy process,the method of determining risk factors weight based on triangular fuzzy numbers is proposed by fuzzy mathematics.The memberships of qualitative and quantitative risk factors are determined.The risk evaluation model for CBM development project is established.A case study using the CBM well data observed from Qinshui basin verifies the applicability of the proposed model.The results indicate that the value for the risk factors of CBM project ranked in descending order:geological resource;technical;economic;political and legal;security;organizational and managerial;social environment.The main reason of the high risk of geological resources is caused by the heterogeneity of coal reservoir and the uncertainty of geological conditions,but such risks can not directly control,it is recommended by improving the drainage technology to try to reduce the risk caused by the geological resources.