庆城油田页岩油水平井压增渗一体化体积压裂技术  

Horizontal Well Volumetric Fracturing Technology Integrating Fracturing,Energy Enhancement,and Imbibition for Shale Oil in Qingcheng Oilfield

作　　者：张矿生[1] 唐梅荣[1] 陶亮[1] 杜现飞[1] ZHANG Kuangsheng;TANG Meirong;TAO Liang;DU Xianfei(Oil and Gas Technology Research Institute,PetroChina Changqing Oilfield Company,Xi’an,Shaanxi,710018,China)

机构地区：[1]中国石油长庆油田分公司油气工艺研究院,陕西西安710018

出　　处：《石油钻探技术》2022年第2期9-15,共7页Petroleum Drilling Techniques

基　　金：国家科技重大专项“鄂尔多斯盆地致密油开发示范工程”(编号:2017ZX05069)资助。

摘　　要：庆城油田页岩油储层低压、低脆性指数特征明显,是阻碍体积压裂后建立高效驱替渗流系统的重要因素,为此,研究了压裂、增能和渗吸(压增渗)一体化体积压裂技术。建立了页岩油储层类型精细划分方法;基于长期产液剖面测试所得矿场大数据,优化了不同储层类型改造策略;利用油藏数值模拟方法,优化了压增渗体积压裂技术关键参数。研究表明:Ⅰ+Ⅱ类储层改造段数占比83.6%,产出占比95.5%,为主要产能贡献段;Ⅲ类储层产出占比仅4.5%,对产能贡献有限,因此,应优先改造Ⅰ+Ⅱ类储层,选择性改造Ⅲ类储层;Ⅰ类和Ⅱ类储层进液强度最优区间分别为20~25 m^(3)/m和15~20 m^(3)/m,增能方式为同步增能。庆城油田200余口页岩油水平井应用了压增渗一体化体积压裂技术,单井初期产油量由9.6 t/d提高至18.0 t/d,单井1年累计产油量由2380 t提高至5256 t,单井估计最终可采量由1.8×10^(4) t提高至2.6×10^(4) t,取得了显著效果。该技术为其他同类非常规页岩油藏高效开发提供了技术借鉴。Shale oil reservoirs in Qingcheng Oilfield have distinct characteristics of low pressure and low brittleness index,which significantly hinder the establishment of an efficient displacement seepage system after volumetric fracturing.In light of this,a volumetric fracturing technology was developed integrating fracturing,energy enhancement,and imbibition.A new method for refined and detailed classification of shale oil reservoirs was formulated.Then,stimulation strategies for different reservoir types were optimized with field big data obtained from tests on long-term fluid production profiles.Finally,the key parameters of the volumetric fracturing technology integrating fracturing,energy enhancement,and imbibition were optimized through the numerical simulation of oil reservoirs.The research results showed that typeⅠand typeⅡreservoirs,making up 83.6%of the stimulated sections and 95.5%of the total production,were the main contributions to productivity.In contrast,the productivity contribution of typeⅢreservoirs accounted for only 4.5%of the total production.Therefore,stimulation treatment priority should be given to typeⅠand typeⅡreservoirs while only some selective sections of typeⅢreservoirs should be stimulated.The optimal intervals of fluid injection intensity for type I and type II reservoirs are 20-25 m^(3)/m and 15-20 m^(3)/m respectively,with synchronous energy enhancement.The volumetric fracturing technology was applied to more than 200 horizontal shale oil wells in Qingcheng Oilfield.The initial single-well production was increased from 9.6 t/d to 18.0 t/d,the single-well annual cumulative oil production was enhanced from 2380 t to 5256 t,and the single-well estimated ultimate recovery(EUR)was improved from 1.8×10^(4) t to 2.6×10^(4) t.This technology has provided a technical reference for the efficient development of similar unconventional shale oil reservoirs.

关 键 词：页岩油 水平井 体积压裂 产液剖面 单井产量 庆城油田 

分 类 号：TE357.1[石油与天然气工程—油气田开发工程]