Permeability-dependent retention of polymer in heterogeneous reservoirs

B. Choi, K. Yu, K. S. Lee

Research output: Chapter in Book/Report/Conference proceedingConference contribution

4 Scopus citations

Abstract

Polymer retention occurring in porous media induces significant mobility reduction as well as poor sweep efficiency. In the heterogeneous reservoir, it is very complicated and difficult to analyze performance of polymer due to permeability-dependent retention. Among various mechanisms of retention, mechanical entrapment of polymer affects mainly the propagation of injected polymer solution by forming macromolecular polymer plugging into pore throats, especially occurring in low permeability zone. Besides, polymer adsorption contributes to mobility reduction and polymer retention. The influence of heterogeneity on polymer retention has been not investigated accurately in the reservoir scale and limited to experimental studies, even though both mechanisms are highly dependent on permeability. In this paper, extensive numerical simulations incorporating mathematical modeling on the retention mechanisms have been performed to examine polymer propagation and flow behavior at various heterogeneous reservoir models. All reservoir models have same average permeability and different Dykstra-Parsons' coefficients (VDP) to represent wide range of reservoir heterogeneity. The results show the amount of polymer adsorption is at high level in low permeability zone. The mechanical entrapment also exhibits same trend with adsorption. Most of polymer retention is accumulated in the low permeability zone, which causes a substantial increase resistance factor in the area. After polymer flooding, total amount of polymer accumulated by retention in the reservoir with VDP=0.72 is 2.5 times more than that of homogeneous reservoir. Furthermore, flow path of polymer solution is restricted to only high permeability zone in the highly heterogeneous reservoir. Thus, the polymer propagates through small pores at a lower rate, giving very poor sweep and irregular propagation path. Sweep efficiency of polymer flooding in the case ofVDP=0.72 is reduced about 33% compared to the case of VDP=0.14. This paper could be helpful for an accurate assessment of polymer retention during polymer floods in the heterogeneous reservoirs.

Original languageEnglish
Title of host publicationOffshore Technology Conference Asia, OTC ASIA 2014
Subtitle of host publicationMeeting the Challenges for Asia's Growth
PublisherOffshore Technology Conference
Pages1809-1827
Number of pages19
ISBN (Print)9781632663870
Publication statusPublished - 2014 Jan 1
EventOffshore Technology Conference Asia: Meeting the Challenges for Asia's Growth, OTC ASIA 2014 - Kuala Lumpur, Malaysia
Duration: 2014 Mar 252014 Mar 28

Publication series

NameProceedings of the Annual Offshore Technology Conference
Volume3
ISSN (Print)0160-3663

Other

OtherOffshore Technology Conference Asia: Meeting the Challenges for Asia's Growth, OTC ASIA 2014
CountryMalaysia
CityKuala Lumpur
Period14/03/2514/03/28

    Fingerprint

Cite this

Choi, B., Yu, K., & Lee, K. S. (2014). Permeability-dependent retention of polymer in heterogeneous reservoirs. In Offshore Technology Conference Asia, OTC ASIA 2014: Meeting the Challenges for Asia's Growth (pp. 1809-1827). (Proceedings of the Annual Offshore Technology Conference; Vol. 3). Offshore Technology Conference.