摘要
异常高压页岩气藏生产中表现为初期产量迅速递减的特征,这种情况一方面和页岩气低渗透压裂投产的方式有关,另一方面可能和储层及压裂缝应力敏感有关。分析了页岩气井储层及压裂缝应力敏感特征,认为储层和压裂缝在力学性质上有较大差别,应分别进行考虑,采用数值模拟方法计算了考虑应力敏感和配产大小对最终采气量的影响,结果表明,储层的应力敏感对页岩气的生产影响较小,压裂缝应力敏感影响相对较大,如果考虑渗透率应力敏感只和压力有关,则配产大小对最终采气量影响不大,而假设高产下具有更强的渗透率应力敏感衰竭曲线,则初期配产对最终采气量影响较大,并采用图形诊断法进行分析,证实了这种情况下初期低配产气井生产潜能更大,研究成果可以用于高压页岩气井的合理配产优化。
Production of abnormal high pressure shale gas reservoir is characteristic of rapid decline of initial production. On the one hand, this is related to the well production by fracturing of low permeability shale gas; on the other hand, it may be related to the pressure-dependent permeability of reservoir and fracture. This paper analyzes the stress- sensitivity of hydraulic fracture and shale gas reservoir, and find out that there is a big difference in the mechanical properties between them, so they should be taken into account separately. By using numerical simulation method, we calculate the effect of pressure-dependent permeability and production allocationon the estimated ultimate recovery （E UR）, and the results show that the effect of stress sensitivity on shale gas reservoir is little, while the influence of hydraulic fracture stress sensitivity is stronger. If stress sensitive permeability is only related to pressure, the production allocation has very little influence on EUR. But if under the high production rate and with stronger permeability stress sensitivity decay curve, the initial production proration has a greater influence on EUR. With graphics diagnosis method, we confirmed that gas wells with lower initial allocation are of greater production potential. The research results can be used for reasonable proration optimization of high pressure shale gas wells.
出处
《西南石油大学学报（自然科学版）》
CAS
CSCD
北大核心
2016年第2期115-121,共7页
Journal of Southwest Petroleum University(Science & Technology Edition)
关键词
页岩气
应力敏感
配产
异常高压
数值模拟
shale gas
stress sensitivity
allocation
abnormal high pressure
reservoir simulation
