Multi-scale synergistic modification of CO2 carbonation coal-based solid waste backfill utilizing high-salinity mine water: Balancing carbon sequestration and engineering performance

Multi-scale synergistic modification of CO2 carbonation coal-based solid waste backfill utilizing high-salinity mine water: Balancing carbon sequestration and engineering performance | 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 Article Multi-scale synergistic modification of CO 2 carbonation coal-based solid waste backfill utilizing high-salinity mine water: Balancing carbon sequestration and engineering performance Zhishang Zhang, Liqiang Ma, Ichhuy Ngo, Yan Ma, Jiangtao Zhai, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8654806/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 16 You are reading this latest preprint version Abstract Addressing the dual challenges of solid and liquid waste management and carbon emissions in the coal industry, this study developed a novel CO 2 -carbonated backfill material (CCB) by synergistically utilizing high salinity mine water (HSW), coal-based solid wastes, and a multi-scale modifier system. The modifiers-rick husk biochar (RHB), natural clinoptilolite (NCP), sepiolite (SEP), and γ-nano Al 2 O 3 (NA)-were incorporated to enhance CO 2 sequestration and engineering performance. Results demonstrate that the composite modifiers significantly improved the carbonation efficiency, achieving a CO 2 uptake of 9.33 mg-CO 2 /g-CCB in the optimal group (CCB-RNn), representing a 25.9% increase over the control. Rheological analysis confirmed the modified slurry retained suitable shear-thinning behavior for transport, while mechanical strength reached 7.48 MPa due to synergistic pore-filling and fiber-reinforcement effects. Microstructural characterization revealed that the modifiers promoted the formation of dense gel networks and finely dispersed carbonate crystals (calcite/magnesite), with NA effectively densifying the matrix and serving as nucleation sites. This work provides a feasible strategy for integrated management of mine water streams and carbon emission, contributing to the development of high-performance, carbon negative backfill technology. Physical sciences/Energy science and technology Physical sciences/Engineering Earth and environmental sciences/Environmental sciences Physical sciences/Materials science CO2 carbonation Carbon-negative backfill High-salinity mine water γ-nano Al2O3 Synergistic modification Carbon sequestration theory Full Text Additional Declarations No competing interests reported. Supplementary Files SupplementaryInformationfiles.docx Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 30 Mar, 2026 Reviews received at journal 29 Mar, 2026 Reviews received at journal 29 Mar, 2026 Reviews received at journal 24 Mar, 2026 Reviewers agreed at journal 23 Mar, 2026 Reviewers agreed at journal 15 Mar, 2026 Reviewers agreed at journal 13 Mar, 2026 Reviews received at journal 06 Mar, 2026 Reviewers agreed at journal 02 Mar, 2026 Reviewers agreed at journal 12 Feb, 2026 Reviewers agreed at journal 03 Feb, 2026 Reviewers invited by journal 27 Jan, 2026 Editor invited by journal 27 Jan, 2026 Editor assigned by journal 22 Jan, 2026 Submission checks completed at journal 22 Jan, 2026 First submitted to journal 20 Jan, 2026 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. 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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-8654806","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":581599207,"identity":"8035f606-fe7d-47e1-a1e9-297bfd547963","order_by":0,"name":"Zhishang Zhang","email":"","orcid":"","institution":"Xinjiang Institute of Engineering","correspondingAuthor":false,"prefix":"","firstName":"Zhishang","middleName":"","lastName":"Zhang","suffix":""},{"id":581599209,"identity":"3abed147-8773-4e7a-ac15-0756d8451d78","order_by":1,"name":"Liqiang 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carbon sequestration and engineering performance\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":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"CO2 carbonation, Carbon-negative backfill, High-salinity mine water, γ-nano Al2O3, Synergistic modification, Carbon sequestration theory","lastPublishedDoi":"10.21203/rs.3.rs-8654806/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8654806/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAddressing the dual challenges of solid and liquid waste management and carbon emissions in the coal industry, this study developed a novel CO\u003csub\u003e2\u003c/sub\u003e-carbonated backfill material (CCB) by synergistically utilizing high salinity mine water (HSW), coal-based solid wastes, and a multi-scale modifier system. The modifiers-rick husk biochar (RHB), natural clinoptilolite (NCP), sepiolite (SEP), and γ-nano Al\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e (NA)-were incorporated to enhance CO\u003csub\u003e2\u003c/sub\u003e sequestration and engineering performance. Results demonstrate that the composite modifiers significantly improved the carbonation efficiency, achieving a CO\u003csub\u003e2\u003c/sub\u003e uptake of 9.33 mg-CO\u003csub\u003e2\u003c/sub\u003e/g-CCB in the optimal group (CCB-RNn), representing a 25.9% increase over the control. Rheological analysis confirmed the modified slurry retained suitable shear-thinning behavior for transport, while mechanical strength reached 7.48 MPa due to synergistic pore-filling and fiber-reinforcement effects. 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This work provides a feasible strategy for integrated management of mine water streams and carbon emission, contributing to the development of high-performance, carbon negative backfill technology.\u003c/p\u003e","manuscriptTitle":"Multi-scale synergistic modification of CO2 carbonation coal-based solid waste backfill utilizing high-salinity mine water: Balancing carbon sequestration and engineering performance","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-29 07:34:57","doi":"10.21203/rs.3.rs-8654806/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-31T00:26:37+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-29T15:33:25+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-29T13:34:05+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-24T09:02:25+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"73113853064832138477102151308002039125","date":"2026-03-23T09:15:35+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"69084916794368377944421186456896124783","date":"2026-03-15T04:39:08+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"220715772561925371876611313785733571843","date":"2026-03-13T04:48:49+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-07T04:38:37+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"236146404436234110563553837691874039798","date":"2026-03-03T04:58:58+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"129224951166892904913006910662385527319","date":"2026-02-12T11:28:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"93829361583658409925440870381356540423","date":"2026-02-03T11:14:57+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-27T16:23:30+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-01-27T15:52:20+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-01-23T01:49:54+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-23T01:49:43+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2026-01-21T03:43:40+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"835dd18f-3726-4f87-97a8-c02f2760a003","owner":[],"postedDate":"January 29th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[{"id":61944404,"name":"Physical sciences/Energy science and technology"},{"id":61944405,"name":"Physical sciences/Engineering"},{"id":61944406,"name":"Earth and environmental sciences/Environmental sciences"},{"id":61944407,"name":"Physical sciences/Materials science"}],"tags":[],"updatedAt":"2026-03-31T00:39:05+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-29 07:34:57","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8654806","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8654806","identity":"rs-8654806","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}