Influence factors and effect prediction model of the tertiary migrations of remaining oil
- PDF / 1,339,707 Bytes
- 10 Pages / 595.276 x 790.866 pts Page_size
- 115 Downloads / 163 Views
ORIGINAL PAPER-PRODUCTION ENGINEERING
Influence factors and effect prediction model of the tertiary migrations of remaining oil Rongda Zhang1,2 · Guanghui Yang1 · Kang Ma2 · Zhichao Song3 · Junjian Li1 · Hanqiao Jiang1 Received: 5 August 2020 / Accepted: 10 October 2020 © The Author(s) 2020
Abstract Worldwide, for older fields that are in the late stages of production period, production wells that lose production value due to high water cut are usually shut down. In this situation, the remaining oil in the reservoir will be re-enriched under the influence of gravity differentiation and capillary forces. Production practices find when the production well is closed for a long time and then opened for restarting production, the water cut drops dramatically and the output rise sharply. In order to anticipate the effects of enrichment of remaining oil in the reservoir, this paper analyzes 10 influencing factors respectively. Secondly, change of water cut before and after shut-in is used as the evaluation index of residual oil enrichment effect. Numerical simulation method is used to simulate the influence of different factors on the effect of external migrations of remaining oil at different levels. Grey correlation analysis is utilized to rank the correlation of 10 factors on residual oil enrichment and then we can get the main controlling factors affecting residual oil enrichment. Finally, the response surface analysis method is used to establish a 5-factor 3-level model, and the corresponding prediction results are obtained through numerical simulation experiments. The main control factors are fitted to obtain the prediction formula of the remaining oil enrichment effect. As a result, we can use the prediction formula to forecast the enrichment effect of remaining oil under different reservoir parameters. Keywords Remaining oil · Correlation analysis · Prediction model · Response surface analysis
Introduction Fault-block reservoirs in China generally enter the late stage of development, and the production cost increases due to the high water cut of production wells (Cui et al. 2017; Kang et al. 2019; Jianmin Wang et al. 2011). Therefore, many Electronic supplementary material The online version of this article (https://doi.org/10.1007/s13202-020-01023-y) contains supplementary material, which is available to authorized users. * Junjian Li [email protected] Rongda Zhang [email protected] 1
Petroleum Engineering Institute, China University of Petroleum (Beijing), Beijing, China
2
State Key Laboratory of Oil and Gas Resources and Exploration, China University of Petroleum (Beijing), Beijing, China
3
Research Institute of Exploration and Development, SINOPEC Shengli Oilfield, Dongying, China
production wells stop to product because of the high water cut and low production value (Han 2010). Yang et al. (2015) point out that residual oil in the formation will enrich under the action of gravity, buoyancy and capillary force. The enrichment process of remaining oil after shut-in is referred to t
Data Loading...
