Abstract
The incentive to revive brownfield oil production extends the interest to apply polymer gel treatments in injection wells. Virtually, volumes of previous remediations implemented in similar reservoir types are used to size new jobs. Such an analogy-based design procedure imposes a need to evaluate the most frequent designs for each reservoir type based on a comprehensive field survey. This survey provides a new treatment sizing strategy for polyacrylamide-polymer bulk gels by reviewing their field applications in 653 injection wells. The new strategy proposes using the average and most frequent gel volumes per reservoir type as an initial estimate of the sizes of new treatments. Five parameters of gel volume were assessed from 65 field projects (1985–2020) using descriptive statistics and stacked bar histograms. Underdesigned or overdesigned projects were identified using the outlier detecting interquartile range method. Multiple scatterplots were employed to determine how treatment timing and reservoir temperature affect treatment sizes. To identify the possible reasons for the failure of gel treatments, unsuccessful pilots were contrasted with effective projects. The review indicates that bulk gel treatments have successfully treated reservoir thief zones with a moveable-pore-volume (mpv) of 30 up to 1,036,000 barrels. Treatment sizes range between 240 and 60,000 barrels; however, gel volumes 20,000 barrels are uncommon in the field. The average size of gel treatments is 10,300 barrels, 300 barrels per foot of perforation, and 21% of thief zone mpvs. In general, the formation type strongly influences treatment sizes and bigger treatments are injected in sandstones and matrix-rock formations than other reservoir types. Treatment sizes decrease with the timing of gel treatments and increase with the formation temperature. The most common cause of gel pilots' failure is the inadequate sizing of gel treatments. For unconventional reservoirs, treatment sizes range between 300 and 590 barrels, with a mean of 414 barrels or 15.8 Barrels per perforated foot. The results also revealed that all gel treatment responses improve for all reservoir types as the gel volume increases, not just oil production and not just for matrix formations. Consequently, the 'bigger-is-better' strategy is also advised for unconsolidated and fractured reservoirs as with matrix formations. Rather than using designs of a few similar treatments, the present review supplies a profound idea of gel treatment volumes for various reservoir types. It will significantly facilitate gel treatment sizing and reduce the time required to find analogues for a candidate reservoir.
Recommended Citation
M. Aldhaheri et al., "A New Design Strategy for Sizes of Polymer Gel Treatments Derived from a Comprehensive Assessment of their Case Histories," Geoenergy Science and Engineering, vol. 237, article no. 212782, Elsevier, Jun 2024.
The definitive version is available at https://doi.org/10.1016/j.geoen.2024.212782
Department(s)
Geosciences and Geological and Petroleum Engineering
Second Department
Chemical and Biochemical Engineering
Keywords and Phrases
Brownfields; EOR floods; Field projects; Gel treatment volume; HPAM-Cr3 gels; Treatment-sizing strategy
International Standard Serial Number (ISSN)
2949-8910
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 Elsevier, All rights reserved.
Publication Date
01 Jun 2024
Included in
Biochemical and Biomolecular Engineering Commons, Geological Engineering Commons, Petroleum Engineering Commons
