A core flood and microfluidics investigation of nanocellulose as a chemical additive to water flooding for eorShow others and affiliations
2020 (English)In: Nanomaterials, E-ISSN 2079-4991, Vol. 10, no 7, article id 1296Article in journal (Refereed) Published
Abstract [en]
Cellulose nanocrystals (CNCs) and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)- oxidized cellulose nanofibrils (T-CNFs) were tested as enhanced oil recovery (EOR) agents through core floods and microfluidic experiments. Both particles were mixed with low salinity water (LSW). The core floods were grouped into three parts based on the research objectives. In Part 1, secondary core flood using CNCs was compared to regular water flooding at fixed conditions, by reusing the same core plug to maintain the same pore structure. CNCs produced 5.8% of original oil in place (OOIP) more oil than LSW. For Part 2, the effect of injection scheme, temperature, and rock wettability was investigated using CNCs. The same trend was observed for the secondary floods, with CNCs performing better than their parallel experiment using LSW. Furthermore, the particles seemed to perform better under mixed-wet conditions. Additional oil (2.9–15.7% of OOIP) was produced when CNCs were injected as a tertiary EOR agent, with more incremental oil produced at high temperature. In the final part, the effect of particle type was studied. T-CNFs produced significantly more oil compared to CNCs. However, the injection of T-CNF particles resulted in a steep increase in pressure, which never stabilized. Furthermore, a filter cake was observed at the core face after the experiment was completed. Microfluidic experiments showed that both T-CNF and CNC nanofluids led to a better sweep efficiency compared to low salinity water flooding. T- CNF particles showed the ability to enhance the oil recovery by breaking up events and reducing the trapping efficiency of the porous medium. A higher flow rate resulted in lower oil recovery factors and higher remaining oil connectivity. Contact angle and interfacial tension measurements were conducted to understand the oil recovery mechanisms. CNCs altered the interfacial tension the most, while T-CNFs had the largest effect on the contact angle. However, the changes were not significant enough for them to be considered primary EOR mechanisms.
Place, publisher, year, edition, pages
MDPI AG , 2020. Vol. 10, no 7, article id 1296
Keywords [en]
Cellulose nanocrystals, Chemical flooding, Enhanced oil recovery, Microfluidics, Nanocellulose, TEMPO-oxidized cellulose nanofibrils
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:ri:diva-45376DOI: 10.3390/nano10071296Scopus ID: 2-s2.0-85087418270OAI: oai:DiVA.org:ri-45376DiVA, id: diva2:1455149
Note
Funding details: Norges Forskningsråd, 244615/E30; Funding details: 262644; Funding text 1: Funding: This research was funded by the Research Council of Norway through grant 244615/E30 in the Petromaks2 program, and trough the Centres of Excellence funding scheme, project number 262644.; Funding text 2: Acknowledgments: The authors would like to thank the Research Council of Norway for their financial support through the GreenEOR project (grant 244615/E30) in the Petromaks2 program, and through the Centres of Excellence funding scheme, project number 262644. The authors would also like to thank master students Yuntian Teng and Hang Bian for collaboration on the core flood experiments. Thank you to NTNU laboratory engineer Roger Overå for assistance, and RISE PFI engineers Ingebjørg Leirset and Mirjana Filipovic for their work with production of the TEMPO‐oxidized CNFs and Per Olav Johnsen for acquiring AFM images.
2020-07-222020-07-222023-05-25Bibliographically approved