引用本文:
【打印本页】   【下载PDF全文】   查看/发表评论  【EndNote】   【RefMan】   【BibTex】
←前一篇|后一篇→ 过刊浏览    高级检索
本文已被:浏览次   下载 本文二维码信息
码上扫一扫!
分享到: 微信 更多
Assessment of fracturing treatment of horizontal wells using SRV technique for Chang-7 tight oil reservoir in Ordos Basin
FAN Jianming1,2, YANG Ziqing1,2, LI Weibing1,2, WANG Chong1,2, HE Youan1,2
(1.Exploration & Development Institute of Changqing Oilfield Company, PetroChina, Xi 'an 710018, China;2.National Engineering Laboratory for Low-Permeability Petroleum Exploration & Development,Xi 'an 710018, China)
Abstract:
A stimulated reservoir volume (SRV) technique was used in a tight oil reservoir (Chang-7) in Ordos Basin of China to increase oil production. The production process in a horizontal well with the SRV treatment was analyzed, and three stages can be characterized, including an initial stable production, a rapid decline period and a stable decline stage. The initial stable production is mainly influenced by the remaining fluids in the SRV that can supply energy for production. During the rapid decline period, the transfer of the energy-supplying from the SRV fluids to dissolved gas driving occurs. In the stable decline stage, oil production is mainly controlled by dissolved gas driving, which is basically conformed to a hyperbolic decline pattern. The SRV treatment and production parameters were optimized based on the data analysis of existing wells. It is suggested that the optimum horizontal well spacing is 500 to 600 m, and the interspace distance of hydraulic fracturing intervals is best of 90 m. The injection rate of the fracturing fluid can be set as 10 to 12 m3/min, with the total fluid volume of 1100 m3 during each treatment and with 100 m3 sands. The bottomhole flow pressure is better retained approximately greater than the bubble pressure in the initial stable stage, and can be slightly less than the bubble pressure in the rapid decline stage, while it should be not less than 2/3 of the bubble pressure in the stable decline stage. The initial production rate of the wells treated by the SRV technique is 8-10 times higher than that of the un-treated, and the annually cumulative production of the SRV treated horizontal wells is 1.4 to 1.8 times of those fractured vertical wells with the same coverage area.
Key words:  tight oil  stimulated reservoir volume  horizontal wells  fracturing  Ordos Basin