Development of a Drip-Biofilter Microbial Fuel Cell System with Air-Gap Isolation for Enhanced Wastewater Treatment and Power Generation

Development of a Drip-Biofilter Microbial Fuel Cell System with Air-Gap Isolation for Enhanced Wastewater Treatment and Power Generation | 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 Development of a Drip-Biofilter Microbial Fuel Cell System with Air-Gap Isolation for Enhanced Wastewater Treatment and Power Generation Chih-Hung Wu, Xiang Wang, Xiaowen Liu, Jiahua Zhang, Le Li This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7298179/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Traditional stacked microbial fuel cell (MFC) systems exhibit significant limitations in continuous-flow wastewater treatment due to cross-interference from interconnected anolyte solutions, leading to voltage stacking failure and impeding scale-up. To address this, a novel drip biofilter-based tubular air-cathode MFC (DB-TAC-MFC) system was developed by integrating a drip-biofilter box with a tubular air-cathode MFC and introducing an air-gap isolation design. Key innovations include: (1) a uniform drip distribution mechanism for stable mass transfer via liquid film; (2) an air-gap modular configuration (8 mm spacing) that prevents substrate cross-conduction; and (3) a synergistic 3D electrode–biofilm system using conductive filter media for electroactive microbial enrichment. Operated under an influent COD of 1100 mg/L, the three-unit DB-TAC-MFC achieved a peak voltage of 1.14 V, a volumetric power density of 5218.3 mW/m 3 at 1.2 MΩ, and maintained 75% COD removal over 72 h. This design effectively resolves voltage stacking issues, enhances energy stability, and provides a scalable solution for decentralized wastewater treatment with integrated energy recovery. Physical sciences/Energy science and technology/Fuel cells Physical sciences/Energy science and technology/Renewable energy/Bioenergy/Biofuels/Crop waste Earth and environmental sciences/Environmental sciences/Environmental chemistry/Pollution remediation Scientific community and society/Energy and society/Energy access air-gap isolation uniform drip distribution serial voltage stacking Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Full Text Additional Declarations There is NO Competing Interest. none Table 1 is available in the Supplementary Files section. Supplementary Files Tables.docx Table 1. Power generation performance of different MFCs stack systems Cite Share Download PDF Status: Posted Version 1 posted 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-7298179","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":498661799,"identity":"94bd469c-a12e-4551-91b2-775a5343680f","order_by":0,"name":"Chih-Hung Wu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAx0lEQVRIiWNgGAWjYDACCcY2ZhDND8TMpGmRbIBq4SGshYENrNLgALFa+Gc3tz0ubLtjt/lG8sHPBQx35OwJWnLnYLvxzLZnydtupCVLz2B4ZkzQFgOJxDZp3rbDyWY3cgykeRgOJ/YQrcV4Rv7n30At9URrsTOQyGED2ZJA0GESN4BaeM4dTpA488zMmsfgsGHPAQJa+GekP5PmKTtsz9+e/Pg2T8VhefYGQtZAQWKDQALInUQqBwF7Bn5CDhoFo2AUjIIRCwBM2zz6gMODygAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0002-2295-1013","institution":"Sanming university","correspondingAuthor":true,"prefix":"","firstName":"Chih-Hung","middleName":"","lastName":"Wu","suffix":""},{"id":498661800,"identity":"df098f07-c848-404b-a3a0-1fa42548be35","order_by":1,"name":"Xiang Wang","email":"","orcid":"","institution":"Sanming university","correspondingAuthor":false,"prefix":"","firstName":"Xiang","middleName":"","lastName":"Wang","suffix":""},{"id":498661801,"identity":"75499a85-5678-46a0-b0e0-bf7a013e4c6e","order_by":2,"name":"Xiaowen Liu","email":"","orcid":"","institution":"Sanming university","correspondingAuthor":false,"prefix":"","firstName":"Xiaowen","middleName":"","lastName":"Liu","suffix":""},{"id":498661802,"identity":"138d1169-0f20-4f05-b9d5-6fd315b10ca5","order_by":3,"name":"Jiahua Zhang","email":"","orcid":"","institution":"Sanming university","correspondingAuthor":false,"prefix":"","firstName":"Jiahua","middleName":"","lastName":"Zhang","suffix":""},{"id":498661803,"identity":"a5f8babb-1f3f-4f65-8cc5-d5a2227c9cdd","order_by":4,"name":"Le Li","email":"","orcid":"","institution":"Sanming university","correspondingAuthor":false,"prefix":"","firstName":"Le","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2025-08-05 08:35:28","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7298179/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7298179/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":88923176,"identity":"d1457d92-64ea-4f20-9a49-b4a191cfc97d","added_by":"auto","created_at":"2025-08-12 18:02:04","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":79250,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of the tubular air-cathode microbial fuel cell system\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7298179/v1/920b94b37330be3607818904.png"},{"id":88923706,"identity":"0036e65e-c92c-4c8d-9afa-9f26aad946c8","added_by":"auto","created_at":"2025-08-12 18:10:04","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":205812,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of the TAC-MFC; 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To address this, a novel drip biofilter-based tubular air-cathode MFC (DB-TAC-MFC) system was developed by integrating a drip-biofilter box with a tubular air-cathode MFC and introducing an air-gap isolation design. Key innovations include: (1) a uniform drip distribution mechanism for stable mass transfer via liquid film; (2) an air-gap modular configuration (8 mm spacing) that prevents substrate cross-conduction; and (3) a synergistic 3D electrode–biofilm system using conductive filter media for electroactive microbial enrichment. Operated under an influent COD of 1100 mg/L, the three-unit DB-TAC-MFC achieved a peak voltage of 1.14 V, a volumetric power density of 5218.3 mW/m\u003csup\u003e3\u003c/sup\u003e at 1.2 MΩ, and maintained 75% COD removal over 72 h. 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