天 然 气 工 业Natural Gas Industry 第41卷第2期2021年 2月· 100 ·苏里格气田致密砂岩气藏开发认识与稳产建议王继平1,2 张城玮3 李建阳4 李娅1,2 李小锋1,2 刘平1,2 陆佳春51.中国石油长庆油田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.中国石油大学(北京)石油工程学院4.中国石油长庆油田公司气田开发事业部5.中国石油长庆油田公司苏里格气田开发分公司摘要:鄂尔多斯盆地苏里格气田致密砂岩气藏的天然气储量规模和年产气量目前都位居全国第一。
为了进一步延长该气田致密砂岩气藏的稳产时间、提高气藏采收率,总结了该气田致密砂岩气开发过程中所取得的地质与气藏工程认识,梳理了影响气田持续稳产的难点问题,提出了该气田致密砂岩气藏下一步的开发建议。
研究结果表明:①苏里格气田致密砂岩气藏有效砂体规模、储层物性、含气性等都具有强非均质性特征,并且局部气水关系复杂;②不同区域气井产量、累计产气量、产量递减率等存在着明显的差异,气藏采收率受储层品质和开发井网的影响大;③优质储层储量动用程度高、储量劣质化趋势明显、剩余储量碎片化现象严重,导致该气田致密砂岩气藏稳产难度大;④为了实现该气田的长期稳产,针对致密砂岩气藏强非均质性的特征,需要进一步推广“基础井组+基础井网+差异化加密”的井网部署策略,持续推进动/静态分析相结合的储层精细描述技术和混合井型部署技术,运用老井查层补孔、侧钻水平井及重复改造等手段提高储量动用程度,配合地质工程一体化改造工艺技术提升储层改造的有效性,采用智能化和水平井高效排水采气工艺技术提升气田精细化管理水平,并且尽早推广“负压”开采技术,以恢复濒临废弃井的生产能力;⑤寻求必要的财税政策支持是实现致密气资源充分利用的重要保障。
关键词:鄂尔多斯盆地;苏里格气田;致密砂岩气藏;储集层特征;开发指标;剩余储量;挖潜对策DOI: 10.3787/j.issn.1000-0976.2021.02.012Tight sandstone gas reservoirs in the Sulige Gas Field:Development understandings and stable-production proposals WANG Jiping1,2, ZHANG Chengwei3, LI Jianyang4, LI Ya1,2, LI Xiaofeng1,2, LIU Ping1,2, LU Jiachun5(1. Exploration and Development Research Institute, PetroChina Changqing Oilfield Company, Xi'an, Shaanxi 710018, China;2. Nation-al Engineering Laboratory of Low-Permeability Oil & Gas Exploration and Development, Xi'an, Shaanxi 710018, China;3. School of Petroleum Engineering, China University of Petroleum, Beijing 100249, China;4. Development Department, PetroChina Changqing Oil-field Company, Xi'an, Shaanxi 710018, China;5. Sulige Gas Field Development Branch, PetroChina Changqing Oilfield Company, Xi'an, Shaanxi 710018, China)Natural Gas Industry, vol.41, No.2, p.100-110, 2/25/2021. (ISSN 1000-0976; In Chinese)Abstract: The Sulige Gas Field in the Ordos Basin ranks the first in China in terms of reserve scale and annual gas production of tight sandstone gas reservoirs. In order to further extend the stable production time and enhance the recovery factor of tight sandstone gas reservoirs in the Sulige Gas Field, this paper summarizes the geological and gas reservoir engineering understandings obtained in the development process of tight sandstone gas in this gas field, sorts out the difficulties impacting its sustainable stable production, and pro-poses suggestions for the following development of tight sandstone gas reservoirs in this field. And the following research results were obtained. First, the effective sand body scale, reservoir physical property and gas bearing property are strongly heterogeneous and the lo-cal gas–water relationship is complex in the tight sandstone gas reservoirs of the Sulige Gas Field. Second, there are obvious differences in gas well production, accumulative gas production and decline rate in different regions. The recovery factor of the gas reservoirs is af-fected more by reservoir quality and development well pattern. Third, the reserve producing degree of good-quality reservoirs is high, the tendency of poor-quality reserves is obvious and the fragmentation of remaining reserves is serious, which increases the production sta-bilization difficulty in the tight sandstone gas reservoirs of the Sulige Gas Field. Fourth, in order to realize sustainable stable production in the Sulige Gas Field, considering the strong heterogeneity characteristics of tight sandstone gas reservoirs, it is recommended to popu-larize the well pattern deployment strategy of "basic well group + basic well pattern + differential infilling" further, continuously improve fine reservoir description technology and mixed well deployment technology with combined dynamic and static analysis, apply layer reviewing and reperforating of old wells, horizontal well sidetracking and re-stimulation to improve the reserve producing degree, adopt the geology–engineering integrated stimulation technology to improve the effectiveness of reservoir stimulation, make use of intelligent and efficient drainage gas recovery technology by horizontal well to improve the fine management level of gas field, and popularize the "negative pressure" production technology as soon as possible to recover the production capacity of wells on the verge of abandonment. Fifth, seeking for the necessary fiscal and tax support is an important guarantee for the full utilization of tight gas resources. Keywords: Ordos Basin; Sulige Gas Field; Tight sandstone gas reservoir; Reservoir characteristics; Development indexes; Remaining re-serves; Potential tapping countermeasures基金项目:国家科技重大专项“鄂尔多斯盆地大型低渗透岩性地层油气藏开发示范工程”(编号:2016ZX05050)、中国石油天然气股份有限公司重大科技专项“长庆气田稳产及提高采收率技术研究”(编号:2016E-0509)。