Adaptability of Organic Matter and Solid Content to Fe2+/Persulfate and Skeleton Builder Conditioner for Waste Activated Sludge Dewatering

Adaptability of Organic Matter and Solid Content to Fe2+/Persulfate and Skeleton Builder Conditioner for Waste Activated Sludge Dewatering | 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 Adaptability of Organic Matter and Solid Content to Fe 2+ /Persulfate and Skeleton Builder Conditioner for Waste Activated Sludge Dewatering Xiaoran Li, Yafei Shi, Xi Zhou, Lu Wang, Huiqin Zhang, Kewu Pi, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-341579/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 07 Oct, 2021 Read the published version in Environmental Science and Pollution Research → Version 1 posted 4 You are reading this latest preprint version Abstract Sludge conditioning is important for improved dewatering, with the sludge characteristics impacting the effect of conditioning. A composite conditioner, Fe 2+ activated sodium persulfate (Fe 2+ /SPS) combined with phosphogypsum (PG), was used to examine its impact on sludges with different organic content or different solid content. Response surface optimization analysis shows that when the best conditioning is achieved, the reduction of the specific resistance to filtration is not sensitive to organic matter content, but the dewatering performance of the sludge is greatly affected by the solid content. The oxidation role of Fe 2+ /SPS and the skeleton builder role of PG, together, affect the conditioning, with oxidation playing a major role in conditioning, especially for greater organic matter content. The organic content also affects the effectiveness of the skeleton builder more than the solid content. Changes in PG significantly impacts the optimal molar ratio and dosage of Fe 2+ /SPS. Sludge with greater solid content requires greater Fe 2+ /SPS dosage to provide stronger oxidation to destroy flocs. The composite conditioning decreases the content of extracellular polymeric substances and proteins/polysaccharides with the decrease in protein content being significantly greater than that of polysaccharides, these decreases improve the sludge dewaterability. Environmental Engineering Environmental Policy Sewage sludge Conditioning Persulfate oxidation Skeleton builder Dewaterability Extracellular polymeric substances Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Full Text Tables Table 1 Basic characteristics of the raw sewage sludge samples. Sludge samples SC ( ±0.2, wt %) OMC ( ±0.1, %) pH ( ±0.2) Viscosity (±0.02, Pa·s) SRF ( ±0.1, × 10 13 m/kg) S 1 4.7 34.6 8.1 0.72 3.6 S 2 4.6 39.3 7.1 0.58 2.1 S 3 4.7 41.3 8.1 0.95 3.4 S 4 4.6 43.8 7.5 0.81 3.5 S 5 5.9 39.3 8.3 5.88 2.5 S 6 4.9 37.2 7.5 0.65 2.4 S 7 3.8 38.2 7.3 0.21 2.2 S 8 2.8 36.7 8.1 0.27 2.6 Table 2 Ranges and levels of factors in the optimization experiments in the design. Conditioning methods Factors (mg/g DS) Level -1 1 Fe 2+ /SPS-PG a (3 wt% SC sludge) A: SPS 80 140 B: Fe 2+ 15 30 C: PG 200 400 Fe 2+ /SPS-PG b (5 wt% SC sludge) A: SPS 80 140 B: Fe 2+ 15 30 C: PG 100 300 Table 3 Summary of optimal conditioning effect of different OMC. SPS, Fe 2+ and PG are in units of mg/g DS. Sludge sample SC of RS ( ±0.2, wt%) SC of CS ( ±0.2, wt%) OMC ( ±0.1, %) SPS (±1) Fe 2+ (±0.2) PG ( ±1) SRF (±0.002, ×10 13 m/kg) Reduction of SRF (%) (Y N ) opt (Y N ) 0 η SOL S 1 4.7 7.0 34.6 118 30.0 300 0.068 98.14±0.07 0.874±0.003 0.783±0.004 0.105±0.001 S 6 4.9 7.0 37.2 115 20.8 300 0.043 98.23±0.09 1.365±0.005 1.186±0.005 0.131±0.008 S 2 4.6 6.7 39.3 115 20.8 300 0.030 98.60±0.10 1.919±0.001 1.559±0.001 0.187±0.001 S 3 4.7 6.7 41.3 139 23.3 210 0.067 98.02±0.06 0.901±0.003 0.771±0.001 0.145±0.005 S 4 4.6 6.7 43.8 115 20.8 300 0.067 98.09±0.06 0.712±0.003 0.656±0.002 0.078±0.002 Table 4 Summary of optimal conditioning effects for different SC. SPS, Fe 2+ and PG are in units of mg/g DS. Sludge sample SC of RS ( ±0.2, wt%) SC of CS ( ±0.2, wt%) SC ( ±0.2, wt%) SPS (±1) Fe 2+ (±0.2) PG (±1) SRF (±0.002, ×10 13 m/kg) Reduction of SRF (%) (Y N ) opt (Y N ) 0 η SOL S 5 5.9 8.4 5.9 115 20.8 300 0.064 97.43±0.08 1.074±0.003 0.942±0.004 0.123±0.002 S 6 4.9 7.0 4.9 115 20.8 300 0.043 98.23±0.09 1.365±0.005 1.186±0.003 0.131±0.008 S 7 3.8 5.5 3.8 115 20.8 300 0.030 98.64±0.08 1.414±0.004 1.205±0.002 0.147±0.005 S 8 2.8 4.1 2.8 115 20.8 300 0.063 97.52±0.09 0.816±0.004 0.726±0.001 0.110±0.003 Supplementary Files Supplementarymaterial.docx Cite Share Download PDF Status: Published Journal Publication published 07 Oct, 2021 Read the published version in Environmental Science and Pollution Research → Version 1 posted Reviews received at journal 04 May, 2021 Reviewers invited by journal 02 May, 2021 Editor assigned by journal 22 Mar, 2021 First submitted to journal 16 Mar, 2021 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-341579","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":24999767,"identity":"0e9e4030-5202-44cc-9151-d3a2bffa7bc1","order_by":0,"name":"Xiaoran Li","email":"","orcid":"","institution":"Hubei University of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Xiaoran","middleName":"","lastName":"Li","suffix":""},{"id":24999768,"identity":"176e06df-b238-4495-8537-7f5f2a7b684f","order_by":1,"name":"Yafei Shi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAxElEQVRIiWNgGAWjYDAC5gNsDAkVBxLAHB6itLAlALWcAWphI0kLYxspWgyOsT978HDenTyD+w2MD962McibE9bCY26QuO1ZscExBmbDuW0MhjsbCGm538MmkbjtcOKGYwxs0rxtDAkGB4hwmETiHLAW9t9EamEwk0hsgNjCTJQWyWM8ZhIJxw4XSx5LbJacc07CcAMhLXxAh0n+qDmcx3f48MEPb8ps5AnaooBQwNgAJCQIqAcC+QbCakbBKBgFo2CkAwAuDES/KXhUDgAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0001-7713-0813","institution":"Hubei University of Technology","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Yafei","middleName":"","lastName":"Shi","suffix":""},{"id":24999769,"identity":"61136c75-5c3a-4878-8ffa-8658852f5af0","order_by":2,"name":"Xi Zhou","email":"","orcid":"","institution":"Hubei University of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Xi","middleName":"","lastName":"Zhou","suffix":""},{"id":24999770,"identity":"d6bfd2eb-2666-43c7-a504-d692551ca556","order_by":3,"name":"Lu Wang","email":"","orcid":"","institution":"Hubei University of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Lu","middleName":"","lastName":"Wang","suffix":""},{"id":24999771,"identity":"1dbfd8d9-7192-4509-9ed9-c34eda4b17bb","order_by":4,"name":"Huiqin Zhang","email":"","orcid":"","institution":"Hubei University of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Huiqin","middleName":"","lastName":"Zhang","suffix":""},{"id":24999772,"identity":"bd64e583-6275-48b3-8d9f-8d0a511076c1","order_by":5,"name":"Kewu Pi","email":"","orcid":"","institution":"Hubei University of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Kewu","middleName":"","lastName":"Pi","suffix":""},{"id":24999773,"identity":"c2c2b2fb-cc35-4ba4-a877-695b236a0378","order_by":6,"name":"Andrea R Gerson","email":"","orcid":"","institution":"Blue Minerals Consultancy","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Andrea","middleName":"R","lastName":"Gerson","suffix":""},{"id":24999774,"identity":"de7e085d-4646-4639-9fb9-f4f73036bb55","order_by":7,"name":"Defu Liu","email":"","orcid":"","institution":"Hubei University of Technology","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Defu","middleName":"","lastName":"Liu","suffix":""}],"badges":[],"createdAt":"2021-03-18 08:08:40","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-341579/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-341579/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s11356-021-16404-x","type":"published","date":"2021-10-07T07:42:22+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":8876745,"identity":"fecef5c6-b384-4834-976a-056474c3fe69","added_by":"auto","created_at":"2021-05-06 20:09:09","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":37773,"visible":true,"origin":"","legend":"Influence of different organic matter content on the optimal response value SRF. RS ─ raw sludge; CS ─ conditioned sludge.","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-341579/v1/834ab04310dcaaef79d1720a.png"},{"id":8876969,"identity":"73c28f5f-dee1-49ab-90ab-183a6b00f408","added_by":"auto","created_at":"2021-05-06 20:12:09","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":73637,"visible":true,"origin":"","legend":"Influence of different organic matter content on sludge dewaterability. PG dosages (mg/g DS) of (a) 100, (b) 200 and (c) 300. (bars refer to SRF and lines refer to reduction of SRF).","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-341579/v1/38445cd528d3fa7ef4351ddf.png"},{"id":8876547,"identity":"6248eecb-9d9b-4987-9621-e1480080b2f7","added_by":"auto","created_at":"2021-05-06 20:06:09","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":52316,"visible":true,"origin":"","legend":"The dynamic relationship between dosage of PG (mg/g DS) and Fe2+:SPS mol ratio with different organic matter contents.","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-341579/v1/8a135ea8cfe1fdbc273921f4.png"},{"id":8876548,"identity":"4141c497-f287-4694-b196-e928e9b2c29a","added_by":"auto","created_at":"2021-05-06 20:06:09","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":29924,"visible":true,"origin":"","legend":"Influence of different solid contents on the optimal response value SRF. RS ─ raw sludge; CS ─ conditioned sludge.","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-341579/v1/69b6f736ad5e1ba8b1bb55db.png"},{"id":8876553,"identity":"31fecc51-ea6b-4a45-8fce-c086998b011b","added_by":"auto","created_at":"2021-05-06 20:06:09","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":48206,"visible":true,"origin":"","legend":"Influence of different solid content on the sludge dewaterability for PG doses (mg/g DS) of (a) 100, (b) 200 and (c) 300.","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-341579/v1/56d6e1fbeebb6f763053b854.png"},{"id":8876747,"identity":"e81c38c3-90a4-4818-87d4-87dfc61b96ed","added_by":"auto","created_at":"2021-05-06 20:09:09","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":50020,"visible":true,"origin":"","legend":"The dynamic relationship between dosage of PG and Fe2+:SPS mol ratio with different solid contents.","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-341579/v1/065318765854eceeab7788dc.png"},{"id":8876748,"identity":"d4dc2a5f-fed5-4221-a8c1-16b66726ed41","added_by":"auto","created_at":"2021-05-06 20:09:09","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":53062,"visible":true,"origin":"","legend":"The changes of EPS content (mg/g DS) before and after sludge conditioning. RS ─ raw sludge; CS ─ conditioned sludge. TB ─ tightly bound; LB ─ loosely bound; S ─ slime. PN ─ protein; PS ─ polysaccharide.","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-341579/v1/6eb95a911b32b902bc835064.png"},{"id":17865741,"identity":"fbe306e6-c603-472e-b161-d02783b93ce8","added_by":"auto","created_at":"2022-02-02 07:42:31","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":847368,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-341579/v1_covered.pdf"},{"id":13629157,"identity":"72e869f8-8984-41b6-a9f7-3fb4228197e6","added_by":"auto","created_at":"2021-09-17 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20:06:09","extension":"docx","order_by":7,"title":"","display":"","copyAsset":false,"role":"supplement","size":90346,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementarymaterial.docx","url":"https://assets-eu.researchsquare.com/files/rs-341579/v1/ae9106aa2a66bf990da69694.docx"}],"financialInterests":"","formattedTitle":"\u003cp\u003eAdaptability of Organic Matter and Solid Content to Fe\u003csup\u003e2+\u003c/sup\u003e/Persulfate and Skeleton Builder Conditioner for Waste Activated Sludge Dewatering\u003c/p\u003e","fulltext":[{"header":"Full Text","content":"This preprint is available for \u003ca href='/article/rs-341579/latest.pdf' target='_blank'\u003edownload as a PDF\u003c/a\u003e."},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1\u003c/strong\u003e Basic characteristics of the raw sewage sludge samples.\u003c/p\u003e\n\u003ctable border=\"1\" width=\"0\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"69\"\u003e\n\u003cp\u003e\u003cstrong\u003eSludge\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003esamples\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u003cstrong\u003eSC\u003cbr /\u003e \u003c/strong\u003e\u003cstrong\u003e(\u003c/strong\u003e\u003cstrong\u003e\u0026plusmn;0.2, wt\u003c/strong\u003e\u003cstrong\u003e%)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e\u003cstrong\u003eOMC\u003cbr /\u003e \u003c/strong\u003e\u003cstrong\u003e(\u003c/strong\u003e\u003cstrong\u003e\u0026plusmn;0.1, \u003c/strong\u003e\u003cstrong\u003e%)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"68\"\u003e\n\u003cp\u003e\u003cstrong\u003epH\u003cbr /\u003e (\u003c/strong\u003e\u003cstrong\u003e\u0026plusmn;0.2)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"101\"\u003e\n\u003cp\u003e\u003cstrong\u003eViscosity\u003c/strong\u003e\u003cstrong\u003e\u003cbr /\u003e \u003c/strong\u003e\u003cstrong\u003e(\u0026plusmn;0.02, Pa\u0026middot;s)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"132\"\u003e\n\u003cp\u003e\u003cstrong\u003eSRF \u003c/strong\u003e\u003cstrong\u003e\u003cbr /\u003e \u003c/strong\u003e\u003cstrong\u003e(\u003c/strong\u003e\u003cstrong\u003e\u0026plusmn;0.1, \u0026times;\u003c/strong\u003e\u003cstrong\u003e10\u003csup\u003e13\u003c/sup\u003e m/kg)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"69\"\u003e\n\u003cp\u003eS\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e4.7\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e34.6\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"68\"\u003e\n\u003cp\u003e8.1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"101\"\u003e\n\u003cp\u003e0.72\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"132\"\u003e\n\u003cp\u003e3.6\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"69\"\u003e\n\u003cp\u003eS\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e4.6\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e39.3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"68\"\u003e\n\u003cp\u003e7.1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"101\"\u003e\n\u003cp\u003e0.58\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"132\"\u003e\n\u003cp\u003e2.1\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"69\"\u003e\n\u003cp\u003eS\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e4.7\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e41.3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"68\"\u003e\n\u003cp\u003e8.1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"101\"\u003e\n\u003cp\u003e0.95\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"132\"\u003e\n\u003cp\u003e3.4\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"69\"\u003e\n\u003cp\u003eS\u003csub\u003e4\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e4.6\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e43.8\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"68\"\u003e\n\u003cp\u003e7.5\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"101\"\u003e\n\u003cp\u003e0.81\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"132\"\u003e\n\u003cp\u003e3.5\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"69\"\u003e\n\u003cp\u003eS\u003csub\u003e5\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e5.9\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e39.3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"68\"\u003e\n\u003cp\u003e8.3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"101\"\u003e\n\u003cp\u003e5.88\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"132\"\u003e\n\u003cp\u003e2.5\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"69\"\u003e\n\u003cp\u003eS\u003csub\u003e6\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e4.9\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e37.2\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"68\"\u003e\n\u003cp\u003e7.5\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"101\"\u003e\n\u003cp\u003e0.65\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"132\"\u003e\n\u003cp\u003e2.4\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"69\"\u003e\n\u003cp\u003eS\u003csub\u003e7\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e3.8\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e38.2\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"68\"\u003e\n\u003cp\u003e7.3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"101\"\u003e\n\u003cp\u003e0.21\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"132\"\u003e\n\u003cp\u003e2.2\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"69\"\u003e\n\u003cp\u003eS\u003csub\u003e8\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e2.8\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e36.7\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"68\"\u003e\n\u003cp\u003e8.1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"101\"\u003e\n\u003cp\u003e0.27\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"132\"\u003e\n\u003cp\u003e2.6\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2\u003c/strong\u003e Ranges and levels of factors in the optimization experiments in the design.\u003c/p\u003e\n\u003ctable border=\"1\" width=\"0\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd rowspan=\"2\" width=\"145\"\u003e\n\u003cp\u003e\u003cstrong\u003eConditioning\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003emethods\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd rowspan=\"2\" width=\"152\"\u003e\n\u003cp\u003e\u003cstrong\u003eFactors\u003cbr /\u003e (mg/g DS)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"270\"\u003e\n\u003cp\u003e\u003cstrong\u003eLevel\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"146\"\u003e\n\u003cp\u003e\u003cstrong\u003e-1\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd rowspan=\"3\" width=\"145\"\u003e\n\u003cp\u003eFe\u003csup\u003e2+\u003c/sup\u003e/SPS-PG\u003csup\u003e a\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003e(3 wt% SC sludge)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eA: SPS\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"146\"\u003e\n\u003cp\u003e80\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e140\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eB: Fe\u003csup\u003e2+\u003c/sup\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"146\"\u003e\n\u003cp\u003e15\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e30\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eC: PG\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"146\"\u003e\n\u003cp\u003e200\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e400\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd rowspan=\"3\" width=\"145\"\u003e\n\u003cp\u003eFe\u003csup\u003e2+\u003c/sup\u003e/SPS-PG\u003csup\u003e b\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003e(5 wt% SC sludge)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eA: SPS\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"146\"\u003e\n\u003cp\u003e80\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e140\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eB: Fe\u003csup\u003e2+\u003c/sup\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"146\"\u003e\n\u003cp\u003e15\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e30\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"152\"\u003e\n\u003cp\u003eC: PG\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"146\"\u003e\n\u003cp\u003e100\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"125\"\u003e\n\u003cp\u003e300\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eTable 3\u003c/strong\u003e Summary of optimal conditioning effect of different OMC. SPS, Fe\u003csup\u003e2+\u003c/sup\u003e and PG are in units of mg/g DS.\u003c/p\u003e\n\u003ctable border=\"1\" width=\"0\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"6%\"\u003e\n\u003cp\u003e\u003cstrong\u003eSludge sample\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e\u003cstrong\u003eSC of RS\u003cbr /\u003e (\u003c/strong\u003e\u003cstrong\u003e\u0026plusmn;0.2, wt%)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e\u003cstrong\u003eSC of CS\u003cbr /\u003e (\u003c/strong\u003e\u003cstrong\u003e\u0026plusmn;0.2, wt%)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"6%\"\u003e\n\u003cp\u003e\u003cstrong\u003eOMC\u003cbr /\u003e (\u003c/strong\u003e\u003cstrong\u003e\u0026plusmn;0.1, %)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"4%\"\u003e\n\u003cp\u003e\u003cstrong\u003eSPS\u003cbr /\u003e \u003c/strong\u003e\u003cstrong\u003e(\u0026plusmn;1)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"5%\"\u003e\n\u003cp\u003e\u003cstrong\u003eFe\u003csup\u003e2+\u003c/sup\u003e\u003cbr /\u003e \u003c/strong\u003e\u003cstrong\u003e(\u0026plusmn;0.2)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"4%\"\u003e\n\u003cp\u003e\u003cstrong\u003ePG\u003cbr /\u003e (\u003c/strong\u003e\u003cstrong\u003e\u0026plusmn;1)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"10%\"\u003e\n\u003cp\u003e\u003cstrong\u003eSRF\u003cbr /\u003e \u003c/strong\u003e\u003cstrong\u003e(\u0026plusmn;0.002,\u003cbr /\u003e \u0026times;10\u003csup\u003e13\u003c/sup\u003e m/kg)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e\u003cstrong\u003eReduction \u003c/strong\u003e\u003cstrong\u003eof SRF (%)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"12%\"\u003e\n\u003cp\u003e\u003cstrong\u003e(Y\u003csub\u003eN\u003c/sub\u003e)\u003csub\u003eopt\u003c/sub\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"9%\"\u003e\n\u003cp\u003e\u003cstrong\u003e(Y\u003csub\u003eN\u003c/sub\u003e)\u003csub\u003e0\u003c/sub\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"13%\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026eta;\u003csub\u003eSOL\u003c/sub\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"6%\"\u003e\n\u003cp\u003eS\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e4.7\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e7.0\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"6%\"\u003e\n\u003cp\u003e34.6\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"4%\"\u003e\n\u003cp\u003e118\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"5%\"\u003e\n\u003cp\u003e30.0\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"4%\"\u003e\n\u003cp\u003e300\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"10%\"\u003e\n\u003cp\u003e0.068\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e98.14\u0026plusmn;0.07\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"12%\"\u003e\n\u003cp\u003e0.874\u0026plusmn;0.003\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"9%\"\u003e\n\u003cp\u003e0.783\u0026plusmn;0.004\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"13%\"\u003e\n\u003cp\u003e0.105\u0026plusmn;0.001\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"6%\"\u003e\n\u003cp\u003eS\u003csub\u003e6\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e4.9\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e7.0\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"6%\"\u003e\n\u003cp\u003e37.2\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"4%\"\u003e\n\u003cp\u003e115\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"5%\"\u003e\n\u003cp\u003e20.8\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"4%\"\u003e\n\u003cp\u003e300\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"10%\"\u003e\n\u003cp\u003e0.043\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e98.23\u0026plusmn;0.09\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"12%\"\u003e\n\u003cp\u003e1.365\u0026plusmn;0.005\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"9%\"\u003e\n\u003cp\u003e1.186\u0026plusmn;0.005\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"13%\"\u003e\n\u003cp\u003e0.131\u0026plusmn;0.008\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"6%\"\u003e\n\u003cp\u003eS\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e4.6\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e6.7\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"6%\"\u003e\n\u003cp\u003e39.3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"4%\"\u003e\n\u003cp\u003e115\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"5%\"\u003e\n\u003cp\u003e20.8\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"4%\"\u003e\n\u003cp\u003e300\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"10%\"\u003e\n\u003cp\u003e0.030\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"8%\"\u003e\n\u003cp\u003e98.60\u0026plusmn;0.10\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"12%\"\u003e\n\u003cp\u003e1.919\u0026plusmn;0.001\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"9%\"\u003e\n\u003cp\u003e1.559\u0026plusmn;0.001\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"13%\"\u003e\n\u003cp\u003e0.187\u0026plusmn;0.001\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd 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width=\"9%\"\u003e\n\u003cp\u003e0.656\u0026plusmn;0.002\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"13%\"\u003e\n\u003cp\u003e0.078\u0026plusmn;0.002\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4\u003c/strong\u003e Summary of optimal conditioning effects for different SC. 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width=\"11%\"\u003e\n\u003cp\u003e0.110\u0026plusmn;0.003\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"environmental-science-and-pollution-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"espr","sideBox":"Learn more about [Environmental Science and Pollution Research](https://www.springer.com/journal/11356)","snPcode":"11356","submissionUrl":"https://submission.nature.com/new-submission/11356/3","title":"Environmental Science and Pollution Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Sewage sludge, Conditioning, Persulfate oxidation, Skeleton builder, Dewaterability, Extracellular polymeric substances","lastPublishedDoi":"10.21203/rs.3.rs-341579/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-341579/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eSludge conditioning is important for improved dewatering, with the sludge characteristics impacting the effect of conditioning. A composite conditioner, Fe\u003csup\u003e2+\u003c/sup\u003e activated sodium persulfate (Fe\u003csup\u003e2+\u003c/sup\u003e/SPS) combined with phosphogypsum (PG), was used to examine its impact on sludges with different organic content or different solid content. Response surface optimization analysis shows that when the best conditioning is achieved, the reduction of the specific resistance to filtration is not sensitive to organic matter content, but the dewatering performance of the sludge is greatly affected by the solid content. The oxidation role of Fe\u003csup\u003e2+\u003c/sup\u003e/SPS and the skeleton builder role of PG, together, affect the conditioning, with oxidation playing a major role in conditioning, especially for greater organic matter content. The organic content also affects the effectiveness of the skeleton builder more than the solid content. Changes in PG significantly impacts the optimal molar ratio and dosage of Fe\u003csup\u003e2+\u003c/sup\u003e/SPS. Sludge with greater solid content requires greater Fe\u003csup\u003e2+\u003c/sup\u003e/SPS dosage to provide stronger oxidation to destroy flocs. The composite conditioning decreases the content of extracellular polymeric substances and proteins/polysaccharides with the decrease in protein content being significantly greater than that of polysaccharides, these decreases improve the sludge dewaterability.\u003c/p\u003e","manuscriptTitle":"Adaptability of Organic Matter and Solid Content to Fe2+/Persulfate and Skeleton Builder Conditioner for Waste Activated Sludge Dewatering","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2021-05-06 20:06:07","doi":"10.21203/rs.3.rs-341579/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2021-05-05T00:01:00+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2021-05-03T00:00:00+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2021-03-23T00:00:00+00:00","index":"","fulltext":""},{"type":"submitted","content":"Environmental Science and Pollution Research","date":"2021-03-16T10:03:22+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"environmental-science-and-pollution-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"espr","sideBox":"Learn more about [Environmental Science and Pollution Research](https://www.springer.com/journal/11356)","snPcode":"11356","submissionUrl":"https://submission.nature.com/new-submission/11356/3","title":"Environmental Science and Pollution Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"9ae168ed-0b61-4ec6-a8da-0fcf38e15baa","owner":[],"postedDate":"May 6th, 2021","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":4120624,"name":"Environmental Engineering"},{"id":4120625,"name":"Environmental Policy"}],"tags":[],"updatedAt":"2022-02-02T07:42:22+00:00","versionOfRecord":{"articleIdentity":"rs-341579","link":"https://doi.org/10.1007/s11356-021-16404-x","journal":{"identity":"environmental-science-and-pollution-research","isVorOnly":false,"title":"Environmental Science and Pollution Research"},"publishedOn":"2021-10-07 07:42:22","publishedOnDateReadable":"October 7th, 2021"},"versionCreatedAt":"2021-05-06 20:06:07","video":"","vorDoi":"10.1007/s11356-021-16404-x","vorDoiUrl":"https://doi.org/10.1007/s11356-021-16404-x","workflowStages":[]},"version":"v1","identity":"rs-341579","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-341579","identity":"rs-341579","version":["v1"]},"buildId":"-HB7Z8yhvgn0wM9Nzuekk","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}