Study On The Coalbed Methane Economic Evaluation Model Based On DEA

The exploration and development of coalbed methane(CBM) have important strategic significances, on one hand it improves China's energy structure and forms a new clean energy industry;On the other hand the exploration of CBM prevents coal mine gas accidents, improves coal mine's safety production condition, reduces gas emission which causes the strong greenhouse effect and protects the global environment. Although of so many benefits, CBM exploration is an industry of high input, high risk and high technology under the current conditions. For reducing the risk, raising reservoir implement efficency and getting the best invest benifits, CBM economical evaluation theories and technologies need to be researched.Based on Project Economics, Technology Economics, Economic Evaluation of Mine, The CBM exploration procedures and difficulties are analyzed firstly.Then the factors and its models affecting CBM project value are defined.However the above parameters distribution characters and change rules are important for CBM economic evaluation model creation by affecting CBM economic evaluation index and DEA model choosing. So some quantity models of the rules from main parameters change are created including the production, reservior parameters, and economic parameters. And the results show that the permeability and CBM price are main effective factors of projects value.Based on above parameters and its functions, the CBM economical economic index system is created. For solving the problem of the parameters often express using interval, Bounded DEA model for CBM economic evaluation is created by combining BNDDEA(Bounded DEA) model and CBM economic evaluation index system. Moreover using this model and some examples, the difference between foreign and domestic CBM plan is founded. And the dfifference tell us which factors are main elements for increasing CBM Production of Panzhuang, so the way for raising production benefits of Panzhuange is proposed.The CBM economic evaluation BNDDEA model only concerns about the whole decision making units.However risk evaluation needs to discove the risk at different points in interval.So it is difficult to study the insides of DMU parameters.For this reason, the method of interval DEA combining montecalo simulation is proposed for determining the effency interval of CBM horizontal well exploration.As a result, the problem of defining CBM exploration optimum scope by DEA model is solved.Finally, with an example of Panzhuang, the production curves of three styles different distance vertical well nets and four styles different length horizontal wells are simulated.In addition the best vertical well plan and horizontal plan are choosen.By comparision of vertical well plan's and horizontal plan's economic parameters,the horizontal well plan is selected. Moreover to discover the uncertainty of horizontal well plan, coefficient of variations and efficency intervals of horizontal well are difined by stastical analysis method and interval DEA-Montecarlo method respectively.The dissertation innovations are as follows.(1)The CBM production curve is analyzied by nolinear theory,and the results show the CBM production curve is long term correlated and chaostic.(2)Using the new created CBM economic evaluation model based on BNDDEA, the difference between foreign and domestic CBM plans is founded. And the dfifference tell us which factors are main elements for increasing CBM Production of Panzhuang, so the way for raising production benefits of Panzhuange is proposed.The results show this method is avoiding human intervention of index weight and give quantity parameters description of increasing CBM projets benefit.(3)Combing interval DEA and montecarlo method,the created uncertainty analysis method of CBM economic evaluation based on interval DEA is used to definite the effency interval of selected horizontal well plan bounded parameters.And the optimum selecting exploration scope is determined.