普光气田开发过程水侵特征分析  

Characteristics of water influx in the development of the Puguang Gas Field,Sichuan Basin

作　　者：李涛[1] 

机构地区：[1]中国石化中原油田普光分公司

出　　处：《天然气工业》2014年第6期65-71,共7页Natural Gas Industry

基　　金：国家重大科技专项"四川盆地普光大型高含硫气田开发示范工程"(编号:2008ZX05048)

摘　　要：四川盆地普光气田为受构造—岩性控制的边水碳酸盐岩孔隙型高含硫气藏,开发过程不希望气藏过早见水而导致产能和采收率下降,以及对管柱和地面工艺设施产生严重的腐蚀。因此,有必要尽早搞清楚该气田的边底水体大小、气藏目前水侵程度、水侵特征及主控因素等问题。为此,首先利用气藏开采过程中的地层压力变化,结合地质情况和生产动态,采用快速褶积积分法和水体影响函数法对水体大小和水体能量进行估算,同时分析水侵量的大小以及水侵速度随时间的变化关系,确定了气田目前水侵动态;然后,在对生产井地层压力和产水量变化特征进行分析的基础上,结合气田地质特征运用克里金插值等分析方法,从气藏工程角度对气田水侵动态进行宏观分析,给出了气田水侵方向趋势图;并运用气藏数值模拟分析方法,通过气田生产历史拟合进一步分析了气田纵横向上来水方向和水侵程度;最后,基于气水两相渗流过程相渗滞后效应设定束缚水饱和度,通过近似模拟水侵形成水封气的程度,进一步分析了水封气对该气田可采储量及采收率的影响。该成果为提高普光气田整体开发效果提供了技术支撑。High sour gas reservoirs were found in the Puguang Gas Field, Sichuan Basin, with edge water and carbonate pores and were controlled by tectonic setting and lithologic features. It is necessary to analyze edge-bottom water volume, water level, water influx characteristics, and main controlling factors so as to avoid poor productivity, low recovery efficiency and the corrosion of pipe strings and surface process facilities, all of which are caused by premature water influx. First, on the basis of formation pressure changes in gas reservoir development as well as geological conditions and production performance, the fast convolution method and water influence function method were adopted to compute water volume and energy and simultaneously analyzed the water influx vol- ume and the relationships between water influx rate and time, thereby to determine the water influx dynamic state in this field. Second, the Kriging and other analysis methods were applied to conduct a macro analysis from the perspective of a gas reservoir project about the produced water influx dynamic status and figured out a produced water influx direction diagram based on the change lea tures of formation pressure and water yield in the production wells and in combination with reservoir geological conditions. Also, the reservoir numerical simulation method was employed to the vertical and horizontal upward water invasion direction and degree through fitting with the production history of this field. Finally, when the irreducible brine saturation was set on the basis of the hys teresis effect of gas-water permeability process, the impact of water-seal gas on recoverable reserves and recovery efficiency was further analyzed through approximate simulation of wate-seal gas formed by water influx. This study provides a technical support for improving the overall development of the Puguang Gas Field.

关 键 词：四川盆地 普光气田 开发 地层水 水侵特征 采收率 腐蚀 控制 

分 类 号：TE37[石油与天然气工程—油气田开发工程]