页岩气压裂水平井产量预测模型研究

Research on Production Prediction Model of Shale Gas Fracturing Horizontal Well

摘要: 准确预测页岩气井生产动态特征是页岩气藏开发的关键。然而，页岩气井通常具有初期产量递减快、后期产量低的生产变化特征，导致页岩气井产量预测难度大。因此，通过考虑页岩气赋存特征，结合等值渗流阻力法，建立了考虑吸附作用下的页岩气压裂水平井产量预测模型，并完成了模型的校验及分析。研究表明：页岩气吸附作用对气井产量影响显著，其中页岩气井产量受Langmuir体积因素影响高于Langmuir压力因素；裂缝半长和压裂段数对页岩气产量影响也是不可忽略的，尽管页岩气井产量与裂缝半长和压裂段数都呈正相关，但裂缝半长对于页岩气井整个生产阶段都有较大的影响，而压裂段数对气井产量的影响会随生产时间的增加而逐渐减小。

Abstract: Accurate prediction of the production dynamic characteristics of shale gas wells is crucial and essential for the development of shale gas reservoirs. However, shale gas wells typically exhibit characteristics of rapid initial production decline and low output in later stages, which is difficult to accurately estimate the ultimate output of shale gas wells during the shale gas development process. Therefore, by considering the characteristics of shale gas occurrence, the production prediction model of shale gas fractured horizontal well under the consideration of adsorption is established with equivalent seepage resistance method, and then the model is verified and analyzed. The results show that shale gas adsorption has a significant effect on gas well production, and the effect of Langmuir volume factor is higher than that of Langmuir pressure factor. The impact of fracture half-length and number of fracturing stages on shale gas production cannot be ignored. Although the production of shale gas wells is positively correlated with the fracture half-length and number of fracturing stages, the fracture half-length has a great impact on the entire production stage of shale gas wells, and the impact of fracturing stages on the production of gas wells will gradually decrease with the increase of production time.