煤层气开发项目风险评估方法  

Risk evaluation methods of CBM development projects

作　　者：夏良玉[1] 罗东坤[1] 代由进[2] 

机构地区：[1]中国石油大学(北京) [2]中联煤层气国家工程研究中心有限责任公司

出　　处：《天然气工业》2012年第3期117-120,135,共4页Natural Gas Industry

基　　金：国家科技重大专项课题"煤层气开发经济评价技术研究"(编号:2011ZX05038-004);国家社科基金重大项目"基于中国石油安全视角的海外油气资源接替战略研究"(批准号:11&ZD164)

摘　　要：蒙特卡洛模拟是油气风险评估的理想方法,但由于国内煤层气产业起步时间短,缺乏模拟所需的历史数据,该方法尚不能用于煤层气领域。为此,在借鉴蒙特卡洛情景模拟及概率分析思想的基础上,采用单因素敏感性分析法筛选风险因素,运用专家调查法估计风险因素的状态值和概率,通过组合各种风险因素状态值模拟决策情景,按照风险识别、风险估计、风险评价的流程构建了煤层气开发项目风险评估模型,再计算出各种情景下的效益值及概率,进而达到评价项目风险的目的。考虑到传统以标准差及标准差系数表征油气开发项目风险与实际投资决策需要不相符,引入了扩展半标准差及扩展半标准差系数作为煤层气开发项目风险评价指标。应用结果表明,在合理评估风险基础上计算得到的期望净现值较无风险净现值更接近项目的真实收益,扩展半标准差系数与标准差系数相比能够更好地表征项目风险。构建的风险评价流程及评估方法可操作性强,可应用于现阶段煤层气开发项目投资决策。The Monte-Carlo Simulation is an ideal method for risk evaluation of oil and gas projects,but unfortunately can not be adaptable for the CBM gas projects for lack of enough historical data,especially under the present situation of CBM gas development at its initial stage.In view of this,based on the basic theories of scenario simulation and probability analysis in the Monte-Carlo Simulation Method,risk factors are first selected by the Sensitivity Analysis,the discrete value and probability of each risk factor are then estimated by use of the Delphi Method.The discrete values of all types of risk factors are combined to simulate the decision context,and a risk evaluation model is built for CBM gas development projects according to the process from risk identification to risk estimation then to risk assessment,on this basis,the profit values and possibility are calculated under different contexts,and thus the risk assessment of a CBM gas project is fulfilled in the end.Because the traditional method based on the standard deviation and its coefficient can not meet the demand of actual investment decisions,the extended semi-standard deviation and its coefficient are introduced as important risk evaluation indexes for CBM projects.Application shows that expected net present value（NPV） which is calculated based on reasonable risk evaluation is more approaching to the real value than that calculated without any risk considered,and the extended half standard deviation and its coefficient are better to characterize the project risk than the standard deviation and its coefficient.The risk evaluation process and method is highly feasible and can be used for decision-making in CBM gas development projects at present.

关 键 词：煤层气开发 概率分析 情景模拟 扩展半标准差 风险评估 投资决策 

分 类 号：TE37[石油与天然气工程—油气田开发工程]