技术经济最优配置的采气速度优化

Optimization of reasonable gas offtake rate considering technical and economic factors

采气速度是气藏最重要的开发指标之一,前人多从稳产期、采出程度等技术方面研究其合理性,而较少考虑经济效益。对于特定地质特征的气藏,存在一个合理的采气速度,使得在技术上满足较高的稳产期采出程度,同时又能在经济上保证较高的效益,以实现动用储量、累计采出程度、经济效益三者的最优配置。文中以澳大利亚海上Bk气田为研究对象,首先,从采出程度、稳产时间等技术指标因素确定了合理开发井数为10口;其次,建立经济效益评价模型,研究了不同采气速度的净现值;最后,构建综合考虑稳产期采出程度和净现值的目标评价函数,确定了Bk气田最优采气速度范围是3.57%~3.93%,与既有规划的3.75%基本一致。研究成果为后续整个项目的产能部署工作奠定了基础。

Offtake rate is one of the most important natural gas reservoir development indexes, most of existing studies focuse on determining its reasonability from technical aspects, such as plateau duration and recovery factor, economic benefits are seldom considered. For a gas reservoir with specific geology features, there is an optimum offtake rate, which makes producing reserve, recovery factor and economic benefits meet at the optimum point. For offshore Bk Gas Field in Australia, ten development wells are deployed considering the recovery factor and plateau duration; economic estimation model is established and the net present values （NPV） for different offtake rates are calculated; considering duration period recovery factor and NPV, the optimal offtake rate range of Bk Gas Field is between 3.57% and 3.93%, which is very close to 3.75% set up by the joint ventures. The research results can be served as the foundation for the whole project＇s subsequent development plan.