长庆油田致密油水平井开发规律  

Researches on the law of oil tight oil reservoir development with horizontal wells of Changqing

作　　者：蒋远征[1,2] 车起君[1,2] 李玉霞 李德生[1,2] 焦军[1,2] 

机构地区：[1]中国石油长庆油田分公司勘探开发研究院 [2]低渗透油气田勘探开发国家工程实验室 [3]中国石油长庆油田分公司第二采油厂地质研究所

出　　处：《低渗透油气田》2015年第2期57-60,共4页

摘　　要：考虑到致密油纳米级孔喉系统，相比超低渗透油藏尺度效应、非牛顿特性、启动压力梯度更强，由水平井产量Joshi公式推导，致密油水平井产量递减呈双曲递减规律；致密油层中水、油流动性更差，油井注水几乎不见效；致密油水平井开发，先是出现产量快速递减，后保持单井产量较低的稳产，属接近自然能量开发模式；致密油层相渗研究，相渗曲线等渗点右移，两相流动区域变窄，油相相对渗透率第1点到第2点下降很快，无渐变点，水相相对渗透率上升快，致密油层最终采收率低；致密油层水平井开发可以提高单井初期产能，但后期补充能量成为难点。In consideration of the nano-level pore-throat system in tight oil reservoirs, compared with those of the uhra-low-permeability reservoirs, the scale effect, non-Newtonian behavior, and starting pressure gradient are stronger in tight oil reservoirs. Derived by the Jostfi formula of horizontal well production, horizontal well production decline of tight reservoirs assumes a hyperbolically diminishing law. The water and oil mobility in tight reservoirs is even worse, leading to the hardly waterflooding response of oil wells. A rapid production rate decline emerges first in tight reservoir development with horizontal wells, then maintains a low individual well production rate, be- longing to as model of nearly natural energy development. According to the study of relative permeability of tight oil reservoirs, isotonic permeability point in relative permeability curves moves right ; two-phase flow area is narrowed. The oil phase relative permeability drops quickly from point 1 to point 2 without a gradual-changing point; while the water phase relative permeability rise fast, leading to low ulti- mate recovery ratio of tight oil reservoirs. Horizontal well development of tight reservoirs can improve the well productivity at initial stage, but difficult to supplement energy later.

关 键 词：递减规律 注水见效 采收率 致密油 

分 类 号：TE341[石油与天然气工程—油气田开发工程]