Experimental Study on CO2 Flooding for Enhanced Oil Recovery in Ultra-Low Permeability Reservoirs of the Songliao Basin

Experimental Study on CO2 Flooding for Enhanced Oil Recovery in Ultra-Low Permeability Reservoirs of the Songliao Basin | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Experimental Study on CO 2 Flooding for Enhanced Oil Recovery in Ultra-Low Permeability Reservoirs of the Songliao Basin Zhongcheng Li, Li Chen, Bin Yue, Hongxue Wang, Wei Chen, Yu He, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8140075/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 12 You are reading this latest preprint version Abstract The Daqingzijing Oilfield in the Songliao Basin is characterized by low porosity and ultra-low permeability, exhibiting significant potential for CO 2 flooding. To further clarify the impact of different CO 2 injection methods on enhanced oil recovery (EOR), long core flooding experiments were conducted, including water flooding, gas flooding, and gas-water alternative flooding with different slug ratios. The results demonstrate that in such ultra-low permeability reservoirs, gas-water alternative flooding can effectively plug CO 2 channeling pathways by forming dynamic Jamin effect slugs, overcoming the limitations of using either gas or water injection alone, achieving a synergistic enhancement effect. Multi-cycle injection significantly enhances oil recovery, with increases of 10.83% and 7.82% observed at slug ratios of 1:2 and 2:1, respectively. A slug ratio of 1:1 was identified as the most suitable for reservoir characteristics, yielding an oil recovery increase of 12.28%. Macroscopically, the slug ratio considerably influences mobility control and sweep efficiency; microscopically, the mass transfer between CO 2 and crude oil predominantly governs flooding efficiency. The composite flooding method of water-alternating-gas can effectively overcome the recovery bottlenecks at different flooding stages, providing technical support for the development of ultra-low permeability reservoirs. CO2 flooding low-permeability reservoir gas-water alternative injection enhanced oil recovery (EOR) Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 25 Apr, 2026 Reviews received at journal 23 Dec, 2025 Reviews received at journal 18 Dec, 2025 Reviews received at journal 16 Dec, 2025 Reviewers agreed at journal 08 Dec, 2025 Reviewers agreed at journal 05 Dec, 2025 Reviewers agreed at journal 03 Dec, 2025 Reviewers agreed at journal 03 Dec, 2025 Reviewers invited by journal 03 Dec, 2025 Editor assigned by journal 21 Nov, 2025 Submission checks completed at journal 21 Nov, 2025 First submitted to journal 17 Nov, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8140075","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":554859792,"identity":"c706e1ed-00bb-4742-9423-8a927eb0f11e","order_by":0,"name":"Zhongcheng Li","email":"","orcid":"","institution":"Exploration and Development Research Institute of Jilin Oilfield","correspondingAuthor":false,"prefix":"","firstName":"Zhongcheng","middleName":"","lastName":"Li","suffix":""},{"id":554859795,"identity":"bc749f6c-e247-4a0f-a545-ddee0111c15e","order_by":1,"name":"Li 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Recovery in Ultra-Low Permeability Reservoirs of the Songliao Basin\u003c/strong\u003e\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":false,"email":"","identity":"journal-of-petroleum-exploration-and-production-technology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"","title":"Journal of Petroleum Exploration and Production Technology","twitterHandle":"","acdcEnabled":false,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"VoR Journals","inReviewEnabled":false,"inReviewRevisionsEnabled":false},"keywords":"CO2 flooding, low-permeability reservoir, gas-water alternative injection, enhanced oil recovery (EOR)","lastPublishedDoi":"10.21203/rs.3.rs-8140075/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8140075/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe Daqingzijing Oilfield in the Songliao Basin is characterized by low porosity and ultra-low permeability, exhibiting significant potential for CO\u003csub\u003e2\u003c/sub\u003e flooding. To further clarify the impact of different CO\u003csub\u003e2\u003c/sub\u003e injection methods on enhanced oil recovery (EOR), long core flooding experiments were conducted, including water flooding, gas flooding, and gas-water alternative flooding with different slug ratios. The results demonstrate that in such ultra-low permeability reservoirs, gas-water alternative flooding can effectively plug CO\u003csub\u003e2\u003c/sub\u003e channeling pathways by forming dynamic Jamin effect slugs, overcoming the limitations of using either gas or water injection alone, achieving a synergistic enhancement effect. Multi-cycle injection significantly enhances oil recovery, with increases of 10.83% and 7.82% observed at slug ratios of 1:2 and 2:1, respectively. A slug ratio of 1:1 was identified as the most suitable for reservoir characteristics, yielding an oil recovery increase of 12.28%. Macroscopically, the slug ratio considerably influences mobility control and sweep efficiency; microscopically, the mass transfer between CO\u003csub\u003e2\u003c/sub\u003e and crude oil predominantly governs flooding efficiency. The composite flooding method of water-alternating-gas can effectively overcome the recovery bottlenecks at different flooding stages, providing technical support for the development of ultra-low permeability reservoirs.\u003c/p\u003e","manuscriptTitle":"Experimental Study on CO2 Flooding for Enhanced Oil Recovery in Ultra-Low Permeability Reservoirs of the Songliao Basin","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-05 14:07:00","doi":"10.21203/rs.3.rs-8140075/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-25T07:35:17+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-23T17:13:05+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-18T14:20:42+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-16T08:10:19+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"80987303249337346039608801099709314940","date":"2025-12-08T10:09:02+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"136005968864349300534067827073618291238","date":"2025-12-05T08:52:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"16131555974609295866081032745786065454","date":"2025-12-03T14:32:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"288879630750395407893674554240632007179","date":"2025-12-03T08:52:55+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-12-03T08:43:07+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-11-21T10:07:19+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-11-21T10:04:19+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Petroleum Exploration and Production Technology","date":"2025-11-18T02:36:09+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":false,"email":"","identity":"journal-of-petroleum-exploration-and-production-technology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"","title":"Journal of Petroleum Exploration and Production Technology","twitterHandle":"","acdcEnabled":false,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"VoR Journals","inReviewEnabled":false,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"fb72a213-03e9-4b6e-ae97-b1cbb8552fb3","owner":[],"postedDate":"December 5th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-04-25T07:39:39+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-05 14:07:00","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8140075","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8140075","identity":"rs-8140075","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}