无因次产气图版在樊庄煤层气产能预测中的应用

数值模拟方法能够较好地描述煤层气的储存特征及流动机理,是目前研究煤层气产能较为有效的方法,但该方法应用费时、复杂,实用性较差。以沁水煤层气田樊庄区块为例,基于煤层气数值模拟方法,建立樊庄无因次产气曲线,研究了13种地质、排采参数对无因次产气曲线的影响,选择影响较大的参数绘制出无因次产气图版。研究结果表明,无因次产气图版能够方便地确定已投产和未投产煤层气井产能、最大产气量及其出现时间、煤层原始含气量等重要参数。实例验证可知,使用无因次产气图版在预测煤层气井产能和确定最大产气量等参数方面,具有较高的准确性。 

Type curves for coalbed methane production prediction in Fanzhuang

Numerical simulation method is the most effective method for coalbed methane production prediction, can describe the storage characteristics and complex flow mechanism of coalbed methane. But it is time-consuming and cumbersome to conduct for production prediction with a reservoir simulator. In this paper, taking Fanzhuang block in Qinshui basin for example, a dimensionless gas production curves were established based on numerical simulation method. Parameters studies were conducted to evaluate the impacts of reservoir properties on the dimensionless gas production curves. On this basis, dimensionless gas production curves were established. The results show that dimensionless gas production curves can be used easily to forecast production of CBM wells which begin production or not and to determine the maximum gas production, gas content and other parameters. An example shows that the prediction results of dimensionless gas production curves is accurate, providing a new method for production prediction for Fanzhuang block in Qinshui basin.