摘要
水平井是高效开发高含硫气藏的主要井型。高含硫气藏在开发过程中,井筒附近压力下降,导致水平井井筒周围形成不规则的硫沉积区,严重的可能导致部分井筒单元没有气体流入。为了更好地对该类气藏进行气井稳产能力预测,构建了水平井分段渗流双区复合物理模型,建立了不稳定渗流数学模型,并采用Laplace积分变换、边界元和压降叠加对井底压力进行了求解。结合不稳定渗流数学模型与高含硫气藏物质平衡方程,构建气井稳产能力预测模型,分析了不同参数对稳产时间和井底压力的影响。研究结果表明:含硫饱和度、堵塞段与渗流段长度比值和水平段长度等对稳产时间和井底压力有着非常明显的影响,含硫饱和度和水平段长度与气井稳产时间呈指数变化关系。通过对元坝气藏某水平井进行实例分析,验证了该方法的准确性,该模型和方法的建立为高含硫气藏水平井稳产能力预测提供了理论依据。
Horizontal wells are main well types of efficient development of high sulfur gas reservoirs.Because of the wellbore pressure decline of the wellbore during the development of high sulfur gas reservoirs,irregular sulfur deposition region will be formed around the horizontal wells,which may seriously lead to no flow in some wellbore units.In order to better predict the stable production capacity of gas wells,a two-zone composite physical model of staged flow in horizontal wells is constructed,and the mathematical model of unstable seepage is established.The wellbore pressure is solved by Laplace transformation,boundary element and pressure drop superposition.The stable production capacity prediction model of gas wells is established by combining the unstable seepage mathematical model and the material balance equation of high sulfur gas reservoirs.The influence of different parameters on stable production time and bottom hole pressure curve is analyzed.The research results show that sulfur saturation,ratio of plugging and seepage section length,and horizontal section length have a very significant impact on stable production time and bottom hole pressure.The relationship between sulfur saturation and horizontal well length and stable production time is exponential.The accuracy of the method is verified by the case analysis of a horizontal well in Yuanba gas reservoir.The establishment of the model and method provides a theoretical basis for the stable production capacity prediction of horizontal wells in high sulfur gas reservoirs.
作者
王勇飞
刘言
梁中红
向祖平
WANG Yongfei;LIU Yan;LIANG Zhonghong;XIANG Zuping(No.2 Gas Production Plant,Southwest Oil&Gas Company,SINOPEC,Nanchong 637000,China;Southwest Oil&Gas Company,SINOPEC,Chengdu 610095,China;Chongqing University of Science and Technology,Chongqing 400041,China)
出处
《断块油气田》
CAS
CSCD
北大核心
2024年第1期140-146,共7页
Fault-Block Oil & Gas Field
基金
中国石化科技项目“高含硫复杂生物礁底水气藏稳产关键技术研究”(P21025)。
关键词
高含硫气藏
硫沉积
水平井
边界元
稳产能力
high sulfur gas reservoir
sulfur deposition
horizontal well
boundary element
stable production capacity
