异常高压气藏地质储量动态分析的半解析压降法

SEMI-ANALYSIS PRESSURE DROP METHOD OF GAS-IN-PLACE DYNAMIC ANALYSIS FOR ABNORMAL HIGH PRESSURE GAS RESERVOIRS

异常高压气藏的开发过程复杂、成本高.为了合理地开发异常高压气藏应合理地进行气藏开发动态分析,文章提出了关于异常高压气藏地质储量计算的新方法.此方法仅需要生产数据不需要考虑地层和流体压缩系数,基于广义物质平衡方程,再结合两个新的函数图版: e(p i-p)～(p/Z)/(p i/Z i)与(p/Z)/(p i/Z i)～G p/G图版,利用图版并结合由图版得到的典型动态曲线匹配技术来确定油气地质储量,运用5个异常高压气藏的生产数据进行分析,实例分析的结果论证了新方法的可靠性.最后推导出一个相关经验公式来估算拐点,这就大大简化了异常高压气藏地质储量的计算,为气藏勘探开发工作提供方便.

Development of abnormal high-pressure gas reservoirs is complicated and of high cost. To develop abnormal high-pressure gas reservoirs properly, the production performance analysis of the gas reservoirs should be conducted properly. The article proposes a new method to calculate the gas-in-place of abnormal high-pressure gas reservoirs. The method requires only the production data, but not the compressibility of formations and fluids.: Based on the generalized material equilibrium equation, combining the 2 new plotting functions: Ce (Pi-P) versus (P/Z)/(Pi/Zi) and (P/Z)/(Pi/Zi) versus Gp/G, the plots, and the matching techniques of the typical dynamic curves derived from the plotting functions are used to determine the oil/gas in place. With the analysis of the production data of 5 abnormal high-pressure gas reservoirs, the analysis results prove the new method is reliable. At last, a related experience formula is derived to estimate the turning point. It is much easier to calculate the gas-in-place of abnormal high-pressure gas reservoirs. It is in favor of exploration and production of gas reservoirs.