Abstract
Controlling excessive water production in mature oil fields has always been a desired objective of the oil and gas industry. This objective calls for planning of more effective water-control gel treatments with optimized designs to obtain more attractive outcomes. Unfortunately, planning such effective treatments remains a dilemma for reservoir engineers due to the lack of methodical design tools in the industry. This paper presents a novel systematic design approach for polyacrylamide-based bulk gel treatments by classifying their field projects according to the gel volume-concentration ratio (VCR) into three design types. In terms of one another, the approach estimates either the gel volume or the gel concentration based on the average gel VCR of each design and formation type. First, field data was collected from SPE papers and reports of US Department of Energy for 65 gel projects conducted between 1985 and 2020. Stacked histograms were then used to examine distributions of field projects according to the gel VCR and the formation type. A comprehensive review of channeling strength indicators in field gel projects was performed to identify the classification criterion and design types of gel treatments. Based on the mean-per-group concept, the average gel VCR was assessed for each design type and formation type to build the design approach. Approximations for the overall gel concentration and correlations for extremum designs were established and included in the approach. The study showed that the gel VCR is a superior design criterion for in-situ forming bulk gel treatments. It aggregates gel treatments into three project groups and ranks them according to the channeling strength. The three project groups have clear separating VCR intervals (3 bbl/ppm) and each of them is mostly dominated by one formation type. The VCR range of each project group represents one design type of the bulk gel treatments. The channeling type is the criterion of grouping and group-wise ranking of gel projects with respect to the gel VCR. In design type I, VCRs/ppm are used to treat pipe-like channeling usually exhibited by unconsolidated sandstones. More balanced VCRs of 1–3 bbl/ppm are designed for fracture-channeling frequently presented in naturally-fractured formations (design type II). Large gel treatments with VCR>3 bbl/ppm are performed to address matrix-channeling often shown in matrix-rock formations (design type III). Prediction results demonstrated that the VCR approach reasonably estimates volumes and concentrations of both single gel treatments and averaged field projects in training and validation samples. Besides its novelty, the new approach is systematic, accurate, practical, and will facilitate the optimization of future gel treatments to improve their performances and success rate.
Recommended Citation
M. Aldhaheri et al., "A Systematic Design Approach For Bulk Gel Treatments Based On Gel Volume-concentration Ratio In Field Projects," Geoenergy Science and Engineering, vol. 221, article no. 211393, Elsevier, Feb 2023.
The definitive version is available at https://doi.org/10.1016/j.geoen.2022.211393
Department(s)
Geosciences and Geological and Petroleum Engineering
Second Department
Chemical and Biochemical Engineering
Keywords and Phrases
Bulk gel treatments; Enhanced oil recovery; Formation and channeling type; Gel volume-concentration ratio; Systematic design approach; Water control
International Standard Serial Number (ISSN)
2949-8910
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2023 Elsevier, All rights reserved.
Publication Date
01 Feb 2023
Included in
Biochemical and Biomolecular Engineering Commons, Geological Engineering Commons, Petroleum Engineering Commons
