{"title":"同时好氧稳定的污水污泥和螯合剂辅助去除有毒金属在一个闭环过程","authors":"Barbara Fojkar, Domen Lestan","doi":"10.1016/j.watres.2025.124653","DOIUrl":null,"url":null,"abstract":"<div><div>Sewage sludge is a valuable source of phosphorus but contains toxic metals that hinder its use as fertilizer. We present a novel process that simultaneously stabilises sludge through post-aerobic digestion (12 days, pH 5.8–7.6, solid-to-liquid ratio 1:25 (dry w/v)) and removes toxic metals using ethylenediaminetetraacetate (EDTA, 10 mM). On average, 74.4% of EDTA was successfully recycled by alkalinization of process solution with quicklime (CaO) to pH 12.5 and reused in subsequent batches. Chelator losses were compensated by the addition of Na-EDTA. Toxic metals, along with excess Ca and Na, were effectively removed from the recycled process solution, enabling closed-loop operation without wastewater generation. During five consecutive batches, total solids in the sludge were reduced by an average of 23.2%, and 74, 61, 26, and 43% of Zn, Cu, Cr, and Pb, respectively, were removed. The leaching of residual toxic metals from the stabilised and decontaminated sludge was further reduced by 55–88% through the addition of zero-valent iron (3% dry w/w). The process also increased the phosphorus concentration in the sludge by 15% and improved its phytoavailability up to 1.8-fold (as determined by ammonium-lactate extraction). This process is sustainable: it preserves valuable nutrients, can be integrated into existing wastewater treatment plant operations, generates only 17% solid waste (relative to the dry weight of the sludge), and produces no wastewater. Due to the recycling of costly EDTA, reagent costs were halved, reaching €73 t<sup>-1</sup> of dry sludge.</div></div>","PeriodicalId":443,"journal":{"name":"Water Research","volume":"288 ","pages":"Article 124653"},"PeriodicalIF":12.4000,"publicationDate":"2025-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Simultaneous aerobic stabilisation of sewage sludge and chelator-assisted removal of toxic metals in a closed-loop process\",\"authors\":\"Barbara Fojkar, Domen Lestan\",\"doi\":\"10.1016/j.watres.2025.124653\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Sewage sludge is a valuable source of phosphorus but contains toxic metals that hinder its use as fertilizer. We present a novel process that simultaneously stabilises sludge through post-aerobic digestion (12 days, pH 5.8–7.6, solid-to-liquid ratio 1:25 (dry w/v)) and removes toxic metals using ethylenediaminetetraacetate (EDTA, 10 mM). On average, 74.4% of EDTA was successfully recycled by alkalinization of process solution with quicklime (CaO) to pH 12.5 and reused in subsequent batches. Chelator losses were compensated by the addition of Na-EDTA. Toxic metals, along with excess Ca and Na, were effectively removed from the recycled process solution, enabling closed-loop operation without wastewater generation. During five consecutive batches, total solids in the sludge were reduced by an average of 23.2%, and 74, 61, 26, and 43% of Zn, Cu, Cr, and Pb, respectively, were removed. The leaching of residual toxic metals from the stabilised and decontaminated sludge was further reduced by 55–88% through the addition of zero-valent iron (3% dry w/w). The process also increased the phosphorus concentration in the sludge by 15% and improved its phytoavailability up to 1.8-fold (as determined by ammonium-lactate extraction). This process is sustainable: it preserves valuable nutrients, can be integrated into existing wastewater treatment plant operations, generates only 17% solid waste (relative to the dry weight of the sludge), and produces no wastewater. Due to the recycling of costly EDTA, reagent costs were halved, reaching €73 t<sup>-1</sup> of dry sludge.</div></div>\",\"PeriodicalId\":443,\"journal\":{\"name\":\"Water Research\",\"volume\":\"288 \",\"pages\":\"Article 124653\"},\"PeriodicalIF\":12.4000,\"publicationDate\":\"2025-09-21\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Water Research\",\"FirstCategoryId\":\"93\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0043135425015568\",\"RegionNum\":1,\"RegionCategory\":\"环境科学与生态学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ENGINEERING, ENVIRONMENTAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Water Research","FirstCategoryId":"93","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0043135425015568","RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, ENVIRONMENTAL","Score":null,"Total":0}
Simultaneous aerobic stabilisation of sewage sludge and chelator-assisted removal of toxic metals in a closed-loop process
Sewage sludge is a valuable source of phosphorus but contains toxic metals that hinder its use as fertilizer. We present a novel process that simultaneously stabilises sludge through post-aerobic digestion (12 days, pH 5.8–7.6, solid-to-liquid ratio 1:25 (dry w/v)) and removes toxic metals using ethylenediaminetetraacetate (EDTA, 10 mM). On average, 74.4% of EDTA was successfully recycled by alkalinization of process solution with quicklime (CaO) to pH 12.5 and reused in subsequent batches. Chelator losses were compensated by the addition of Na-EDTA. Toxic metals, along with excess Ca and Na, were effectively removed from the recycled process solution, enabling closed-loop operation without wastewater generation. During five consecutive batches, total solids in the sludge were reduced by an average of 23.2%, and 74, 61, 26, and 43% of Zn, Cu, Cr, and Pb, respectively, were removed. The leaching of residual toxic metals from the stabilised and decontaminated sludge was further reduced by 55–88% through the addition of zero-valent iron (3% dry w/w). The process also increased the phosphorus concentration in the sludge by 15% and improved its phytoavailability up to 1.8-fold (as determined by ammonium-lactate extraction). This process is sustainable: it preserves valuable nutrients, can be integrated into existing wastewater treatment plant operations, generates only 17% solid waste (relative to the dry weight of the sludge), and produces no wastewater. Due to the recycling of costly EDTA, reagent costs were halved, reaching €73 t-1 of dry sludge.
期刊介绍:
Water Research, along with its open access companion journal Water Research X, serves as a platform for publishing original research papers covering various aspects of the science and technology related to the anthropogenic water cycle, water quality, and its management worldwide. The audience targeted by the journal comprises biologists, chemical engineers, chemists, civil engineers, environmental engineers, limnologists, and microbiologists. The scope of the journal include:
•Treatment processes for water and wastewaters (municipal, agricultural, industrial, and on-site treatment), including resource recovery and residuals management;
•Urban hydrology including sewer systems, stormwater management, and green infrastructure;
•Drinking water treatment and distribution;
•Potable and non-potable water reuse;
•Sanitation, public health, and risk assessment;
•Anaerobic digestion, solid and hazardous waste management, including source characterization and the effects and control of leachates and gaseous emissions;
•Contaminants (chemical, microbial, anthropogenic particles such as nanoparticles or microplastics) and related water quality sensing, monitoring, fate, and assessment;
•Anthropogenic impacts on inland, tidal, coastal and urban waters, focusing on surface and ground waters, and point and non-point sources of pollution;
•Environmental restoration, linked to surface water, groundwater and groundwater remediation;
•Analysis of the interfaces between sediments and water, and between water and atmosphere, focusing specifically on anthropogenic impacts;
•Mathematical modelling, systems analysis, machine learning, and beneficial use of big data related to the anthropogenic water cycle;
•Socio-economic, policy, and regulations studies.