Survey and Data Analysis of the Pilot and Field Polymer Flooding Projects in China
Enhanced oil recovery (EOR) processes are regarded as important methods to recover remaining oil after primary and secondary recovery. It is important to select the most appropriate EOR process among the possible techniques for a candidate reservoir. Therefore, EOR screening criteria have been constructed using available EOR data sets and serve as the first step to compare the suitability of each EOR method for a particular reservoir. Most screening criteria for polymer flooding are based on data sets from EOR surveys published biannually by the Oil & Gas Journal. These surveys missed significant polymer flooding parameters such as formation water salinity and hardness, polymer types and molecular weight, polymer concentration, reservoir heterogeneity, and so on. All of these topics are covered in this paper with data from relevant literature and records provided by oil companies in China. Polymer flooding has been widely applied in China for over 20 years and a large number of pilot and field projects have been conducted. These projects include important information to quantify the development of polymer flooding as an EOR method. Nevertheless, most of them have been published in Chinese, and are not accessible to the global research community due to the language barrier. This paper represents an effort to collect all relevant information of polymer flooding from available Chinese publications and reports from all of the major oil companies in China. The primary objectives of this survey is to reveal EOR advances, to trace the development of the polymer flooding EOR methodology in China, and to benefit EOR worldwide. This project collected information on 55 polymer flooding projects after reviewing nearly 200 publications in Chinese, including 31 pilot projects and 24 field projects from 1991 to 2014. A data set was constructed by collecting all relevant information for polymer flooding. Statistical analyses and graphical methods were used to analyze the whole data set. Box plots combined with violin plots were used to show the distribution and the range of each parameter. By defining and calculating lower and upper limits in box plots, special projects were identified and explained. Scatter plots, which show multiple parameters in one plot, were used to identify significant relationships among different parameters, especially for dependent parameters. This method overcomes some disadvantages of the range method, which is traditionally used for EOR screening. For example, using polymers with high concentration in low salinity reservoirs can lead to higher incremental oil recovery than in high salinity ones, and lower permeability usually correlates with the use of polymers with lower molecular weight. However, the traditional range method cannot show this relationship. Finally, comprehensive screening criteria for polymer flooding were updated based on information revealed in the field application projects.
Y. Zhang et al., "Survey and Data Analysis of the Pilot and Field Polymer Flooding Projects in China," Proceedings of the SPE Improved Oil Recovery Conference (2016, Tulsa, OK), vol. 2016-January, Society of Petroleum Engineers (SPE), Apr 2016.
The definitive version is available at https://doi.org/10.2118/179616-MS
SPE Improved Oil Recovery Conference (2016: Apr. 11-13, Tulsa, OK)
Geosciences and Geological and Petroleum Engineering
Keywords and Phrases
Floods; Low Permeability Reservoirs; Molecular Weight; Oil Well Flooding; Petroleum Engineering; Petroleum Industry; Petroleum Reservoir Engineering; Petroleum Reservoir Evaluation; Petroleum Reservoirs; Polymers; Publishing; Reservoirs (Water); Secondary Recovery; Surveys; Water Hardness; Well Flooding, Enhanced Oil Recovery; Field Application; Formation-Water Salinity; Language Barriers; Multiple Parameters; Polymer Concentrations; Research Communities; Reservoir Heterogeneity; Enhanced Recovery
International Standard Book Number (ISBN)
Article - Conference proceedings
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