WATER RESEARCH
·
2022
·
IF 13.4
Xiaowei Li,Xuan Wang,Lubei Chen,Xiang Huang,Fengying Pan,Lulu Liu,Bin Dong,Hongtao Liu,Hui Li,Xiaohu Dai,Jin Hur
Sewage sludge is an important source for microplastics (MPs) entering into environment. Hydrothermal treatment has been considered a promising method for reducing MPs in sewage sludge. However, MPs degradation characteristics and mechanism during sludge hydrothermal treatment are not fully understood. In the study, three common MPs, i.e. polyethylene (PE), polystyrene (PS) and polyethylene terephthalate (PET) were used to explore the effect of hydrothermal treatment on the properties of MPs in sewage sludge. The hydrothermally-treated (HT) MPs in sludge feature more broken and rougher surfaces with higher O-containing functional groups in the sludge than those in water. The dissolved leachates from the HT MPs in the sludge show higher concentrations than the counterparts, implying that certain components in sludge serve to promote the MP degradation and leaching during hydrothermal treatment. Three model components in the sludge, including protein, carbohydrate, and SiO 2 , were further investigated for their individual effects on the hydrothermal degradation of MPs. Compared with those in water, the HT MPs in the protein and carbohydrate solutions show greater changes in the surface micro-morphologies and carbonyl index, and generate more leachates. However, the SiO 2 solution results in similar difference in the MPs changes with the water solution, indicating that organic components of sludge play a more critical role in the enhanced MPs hydrothermal degradation than inorganic components. The HT PET leads to more pronounced changes in the physicochemical and leaching characteristics than the HT PE and PS, possibly due to more susceptible hydrolysis of the PET. Hydrothermal degradation of the MPs is found to be mainly driven by depolymerization of the polymer and leaching of the plastics additives. The findings imply that the sludge organic components significantly promote the MPs aging and degradation during hydrothermal treatment, and potential changes in the environmental risk of the treated MPs upon their subsequent land applications.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Haonan Zhang,Shaoqing Chen,Nianji Zhang,Huihuang Chen,Yutong Yang,Yang Tu,Chuanlai Jiao,Zian Xu,Yu Xia,Hongri Suo,Zesheng Li,Chongxuan Liu,Hsing-Lin Wang
Electrochemical advanced oxidation processes (EAOPs) are promising technologies for the elimination of organic pollutants in water, but the high cost of the catalysts and treatment process restrict their large-scale application. Herein, highly efficient carbon-based catalysts for EAOPs were obtained by directly pyrolyzing low-cost sewage sludge, over which the elimination rates were up to 98% for methyl orange (MO) and 88% for tetracycline (TC). A precise electrochemical testing system demonstrated that the S-9/Ti electrode with 1.2 g catalyst loading owns the specific energy consumption value for 98% MO (5 mg/L) degradation was only 0.0112 kWh/g, and the value for 88% TC (1*10 -4 M) degradation was only 0.0039 kWh/g, in 8 h. Furthermore, active species capture experiments demonstrated that the •OH and •O 2 – radicals produced over the catalysts were the main oxidants for the elimination of pollutants. This study broadens the horizon for the resource utilization of sewage sludge and provides a strategy to realize the concept of “treating pollution with waste”.
研究领域:
环境科学
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化学工程
·
材料科学
·
水处理
✓ 已验证
产品关联
DOI
高影响因子
Results in Engineering
·
2023
·
IF 5
Shuting Zeng,Jing Sun,Xuyang Lü,Zitong Peng,Bin Dong,Xiaohu Dai,Bing-Jie Ni
Norfloxacin is a broad-spectrum antibiotic which has been frequently detected in the sewage sludge. However, whether norfloxacin in sewage sludge would affect the anaerobic digestion for bioenergy generation and induce environmental risks remained unclear. Therefore, this study investigated the impact of norfloxacin on sewage sludge anaerobic digestion and evaluated potential environmental risks by exploring related antibiotic resistance genes (ARGs) and norfloxacin transformation pathways. The results showed that norfloxacin at environmental relevant concentration ranges would not significantly affect methane production (p < 0.05) during the sludge anaerobic digestion, as the sludge solubilization and hydrolysis is unaffected. However, the individual methanogenesis process was enhanced with the increase of Methanosaeta abundances. Meanwhile, the increase of norfloxacin concentration will not decrease the removal efficiencies of fluoroquinolones-family ARGs by the anaerobic digestion process. However, the norfloxacin concentration is found to be increased during the anaerobic digestion process, which could probably be due to the desorption from the sludge due to cell lysis. In addition, 13 norfloxacin transformation metabolites were identified with 5 potential norfloxacin degradation pathways being constructed. The metabolites of levofloxacin/ofloxacin could be generated through Eschweiler-Clarke reaction, which may be more toxic than norfloxacin. Thus, the results of this study suggested that although norfloxacin would not affect the bioenergy generation and ARG removal during sludge anaerobic digestion, measures should be taken to deal with the potential environmental risks caused by norfloxacin release and formation of more toxic metabolites.
研究领域:
环境科学
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微生物学
·
污水处理
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
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2020
·
IF 5.778
Tianyu Li,Yuzhe He,Xingxing Peng
Sewerage sludge-derived biochars (SSDBCs) with high adsorption capacity and excellent recyclability were synthesized to remove tetrabromobisphenol A (TBBPA) in aqueous system. Scanning electron microscopy, elemental mapping via energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy were used to characterize the morphology, composition, and microstructures. The maximum adsorption capacity of SSDBCs was about 87.02 mg g −1 at 303 K and pH 7.5. The Langmuir isotherm demonstrated that the adsorption was mainly homogeneous and chemical processes. The kinetics of TBBPA removal well fitted the second-order dynamic model. Thermodynamic analysis showed that the adsorption was exothermic. The effect of π−π dispersive force and hydrogen bonding was proven as the main adsorption mechanism. Multiple cycle runs experiment revealed the excellent stability of recycled SSDBCs. This work provided a promising method of sludge resourceful treatment using an efficient, economic, cyclic, and convenient material for typical organic contaminant in the environment.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
ENERGY & FUELS
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2013
·
IF 2.853
Jianzhong Liu,Ruikun Wang,Yourui Hu,Junhu Zhou,Kefa Cen
Municipal wastewater sludge (denoted as sludge hereafter) can be economically and effectively used by mixing it with coal to prepare slurry fuels. However, the abundant extracellular polymeric substances (EPSs) and strong water-holding capacity of raw sludge cause the viscosity of slurry fuel to increase remarkably, which is disadvantageous for industrial applications. The slurrying properties of sludge can be improved by alkaline treatment. This study examined the effects of calcium oxide (CaO) on EPSs, water-holding capacity, floc structure of sludge, and co-slurrying properties of sludge with coal. Results showed that, after CaO modification, the relative amount of EPSs with a number-average molecular weight (Mn) > 5000 Da noticeably decreased, whereas the relative amount of EPSs with Mn < 5000 Da increased. Moreover, the soluble chemical oxygen demand (SCOD) of sludge increased, and its volatile suspended solid (VSS) content decreased. Raw sludge had a SCOD of 16.2 mg of O2/g of dry sludge (DS) and VSS of 58.19%. After treatment with 0.2 g of CaO/g of DS for 24 h, SCOD increased to 153.6 mg of O2/g of DS, VSS decreased to 45.61%, the water-holding capacity of the sludge decreased, and the saturated water content of raw sludge decreased from 84.71 to 79.10%. The characteristic viscosity ηc of the raw sludge–coal slurry was 1635.3 mPa s, which decreased to 1082.2 mPa s after treatment with 0.2 g of CaO/g of DS for 24 h. These findings strongly suggested that sludge solubilization can help improve slurrying.
研究领域:
环境工程
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能源利用
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废物资源化
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胶体与界面化学
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燃料科学
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污泥处理
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化学工程
✓ 已验证
DOI
高影响因子
Nature Water
·
2024
·Vol. 2
·期 7
·649-662
·
IF 0
Gu Chao-Hai,Pan Ya,Wei Ting-Ting,Zhang Ai-Yong,Si Yang,Liu Chang,Sun Zhi-Hu,Chen Jie-Jie,Yu Han-Qing
The worldwide generation of waste sludge emanating from municipal wastewater treatment plants amounts to 80–90 million tons of dry matter annually and continues to escalate, posing a substantial economic and environmental challenge for society. Although waste sludge offers a tantalizing resource to be harnessed, highly efficient and effective strategies for its repurposing remain elusive due to its complex compositions and low concentration of recoverable metallic elements. Here we devise a straightforward methodology for adept transformation of waste sludge into high-value single-atom catalysts (SACs) for water purification. This process involves in situ upcycling of trace redox-reactive transition metals present in sludge into single-atom speciation by carbon, nitrogen, sulfur, phosphorus, silicon and aluminium via the formation of reactive anchoring sites and selective chemical bonds. Sludge-derived SACs demonstrate remarkable reactivity, stability and selectivity in Fenton-like degradation of various contaminants. Structural analyses and density functional theory calculations reveal that co-coordinated iron single atoms act as the principal reactive sites in the catalysts. In addition, other single-atom transition metals with distinct coordination structures form and contribute to catalytic performance. Furthermore, we employ life cycle assessment and payback period analysis to conduct an evaluation of sludge upcycling to SACs with considerations of environmental impacts and production costs at an industrial level. Compared with conventional incineration, the overall life cycle impacts of our upcycling approach on human health, ecosystems and resources are much lower and exhibit a greater potential for reduction of emissions. This innovative technology promises financial benefits, obviates the substantial economic burdens of sludge disposal and charts a new trajectory for waste sludge disposal, promoting the genesis of more sustainable wastewater and waste management frameworks.
研究领域:
环境科学
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催化化学
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废水处理
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材料科学
✓ 已验证
DOI
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Fuhao Zhang,Cheng Shen,Yaqian Zhao,Lingwei Kong,Feng Ju,Bin Ji,Yu Bon Man,Shengdao Shan,Yuliang Li,Jin Zhang
Per- and polyfluoroalkyl substances (PFAS) pose significant risks to human health and ecosystems. Constructed wetlands (CWs), as a nature-based solution, are a promising and cost-effective approach for PFAS remediation. However, most studies have focused on plant uptake and substrate adsorption, neglecting the role of biofilms on CW substrates in PFAS removal. This study examines the differences in biofilms on functional (Sewage Sludge Biochar, SSB) and conventional (gravel) materials and their impact on the removal of perfluorobutane sulfonic acid (PFBS), a typical PFAS substitute. Experimental results show that the biofilm adsorption is the dominant way for PFBS removal in SSB-CW, as the SSB-biofilm adsorption capacity (809.0 ± 9.799 μg/g) significantly higher than that of SSB itself and the gravel-biofilm ( P < 0.05). The high conductivity of SSB, attributed to its graphitic nitrogen content, facilitates the enrichment of electroactive microorganisms and regulates synergistic interactions between electroactive and non-electroactive microbial communities. This, in turn, modifies the biofilm structure and physicochemical properties, leading to increased zeta potential, enhanced hydrophobicity, and altered extracellular polymeric substance (EPS) composition. Consequently, these effects contribute to an improvement in PFBS removal efficiency, reaching 51.162 % ± 0.08. Undoubtedly, biofilms in CWs offer a promising approach for PFAS removal, where their adsorption capacity for PFBS can be regulated through material properties. This regulation reduces PFBS uptake by plants, thereby lowering environmental risks. Given the widespread occurrence of emerging contaminants in aquatic and terrestrial environments, this strategy provides valuable insights for PFAS remediation in surface water, groundwater, and soil systems.
研究领域:
环境工程
·
水处理
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微生物学
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生态毒理学
·
吸附科学
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材料科学
·
环境修复
✓ 已验证
产品关联
DOI
高影响因子
PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2014
·
IF 3.828
Shuai Liu,Mengmeng Wei,Yu Qiao,Zhenle Yang,Ben Gui,Yun Yu,Minghou Xu
This study reports the release of five sulfur-containing odorants (H 2 S, SO 2 , COS, CS 2 and CH 3 SH) during the pyrolysis of sewage sludge. Pyrolysis experiments using both raw sewage sludge and seven sludge samples loaded with various organic sulfur compounds were performed to determine the effects of the type of organic sulfur on the release of sulfur-containing gases. It was observed that the formation of H 2 S, the predominant odorant, significantly increases at temperatures above 150 °C. Aliphatic and aromatic sulfur compounds were found to be the two main organic sulfur sources for the release of sulfur-containing gases. The release of sulfur-containing gases from aliphatic sulfur greatly increases at 250 °C, whereas significant sulfur-containing gases are released from aromatic sulfur at relatively high temperatures of 350–450 °C. It was also observed that the presence of sulphonic acid and thiophene in sludge does not significantly affect the release of sulfur-containing gases.
研究领域:
环境科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Zengming Tang,Dong Xie,Suzhe Li,Xiaomin Yang
Finding an inexpensive and efficient porous adsorbent to capture the gaseous radioiodine generated during spent fuel reprocessing has been challenging. Herein, we present a design philosophy for waste control to develop porous carbon for gaseous iodine capture from sewage sludge waste. Among them, the novel in situ etching of polytetrafluoroethylene was employed to improve pore accessibility. The hazards of the conventional preparation of sludge-derived carbon using highly corrosive NaOH and HF solutions were overcome. Polytetrafluoroethylene etched porous carbon with large specific surface area (1103 m 2 /g), interconnected hierarchical porous structure, and excellent hydrophobicity (water contact angle 126.52°), providing efficient adsorption of gaseous iodine in hot (30–150 °C) and humid (50–96% relative humidity [RH]) environments. The iodine adsorption of hierarchical porous carbon was tested under static and dynamic conditions, and high records have been achieved. Notably, due to the structural advantage of hydrophobicity, a considerable dynamic adsorption capacity (1746.77 mg/g) was also maintained in a mixed iodine gas stream containing water vapor in a humid (50% RH) hot (75 °C) condition. This study is the first to use an in situ etching strategy for polytetrafluoroethylene, which opens a new avenue for converting sludge waste into low-cost porous carbon and provides an attractive option for capturing iodine in hot and humid environments.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2019
·
IF 7.913
Jingjing Chen,Siqi Tang,Feng Yan,Zuotai Zhang
Reclaiming abundant phosphorus from sewage sludge (SS) via pyrolysis for use as a fertilizer has gained increasing attention owing to the rapid depletion of global P reserves. In this study, the enhancement effect of Ca-based additives on sludge P transformation to hydroxylapatite through pyrolysis was systematically investigated. Three Ca-based additives were added in the pyrolysis of SS, and they were found to promote the conversion of sludge P to hydroxylapatite , which is bioavailable to plants. The characterization of the sludge-derived pyrochars indicated that the addition of 10% CaO, 5% Ca(OH) 2 , or 10% Ca 3 (PO 4 ) 2 facilitated peak hydroxylapatite production. The thermodynamic simulation of the production of hydroxylapatite during pyrolysis showed that these additives increased the enthalpy of the pyrolysis system. Furthermore, the pyrolysis with CaO addition had the lowest enthalpy, thereby suggesting that the addition of CaO during sludge pyrolysis was preferable for recovering sludge P in the form of hydroxylapatite. Moreover, the hydroxylapatite produced with these additives was unstable when the pyrolysis temperature was above 900 °C. The pot experiment demonstrated the feasibility using the sludge-derived pyrochars as P fertilizer for plant growth. Therefore, changing the Ca form and/or Ca/P ratio with the addition of Ca-based additives could be an effective strategy for reclaiming P from SS in the form of hydroxylapatite, and this demonstrates a pathway for global P sustainability by recycling P from P-abundant wastes.
研究领域:
环境科学
·
废物管理
·
农业化学
✓ 已验证
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2020
·
IF 2.627
Nanhang Dong,Ruiqiang Huo,Ming Liu,Lisheng Deng,Zhengbing Deng,Guozhang Chang,Zhen Huang,Hongyu Huang
Chemical looping gasification (CLG) provides a novel approach to dispose the sewage sludge. In order to improve the reactivity of the calcined copper slag , NiO modification is considered as one of the good solutions. The copper slag calcined at 1100 °C doped with 20 wt% NiO (Ni20-CS) was used as an oxygen carrier (OC) in sludge CLG in the work. The modification of NiO can evidently enhance the reactivity of copper slag to promote the sludge conversion, especially for sludge char conversion. The carbon conversion and valid gas yield ( V g ) increase from 67.02% and 0.23 m 3 ·kg −1 using the original OC to 78.34% and 0.29 m 3 ·kg −1 using the Ni20-CS OC, respectively. The increase of equivalent coefficient ( Ω ) facilitates the sludge conversion and a suitable Ω value is determined at 0.47 to obtain the highest valid gas yield (0.29 m 3 ·kg −1 ). A suitable steam content is assigned at 27.22% to obtain the maximum carbon conversion of 87.09%, where an acceptable LHV of 12.63 MJ·m −3 and V g of 0.39 m 3 ·kg −1 are obtained. Although the reactivity of Ni20-CS OC gradually decreases with the increase in cycle numbers because of the generation of NiFe 2 O 4- δ species, the deposition of sludge ash containing many metallic elements is beneficial to the sludge conversion. As a result, the carbon conversion shows a slight uptrend with the increase of cycle numbers in sludge CLG. It indicates that the Ni20-CS sample is a good OC for sludge CLG.
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Ying Xu,Yiqing Lu,Linke Zheng,Zhiwei Wang,Xiaohu Dai
A sludge structure perspective of the effects of humic matter (HM) on the anaerobic digestion (AD) of sewage sludge was proposed and investigated in this study. It was observed that the net cumulative methane production of sludge was significantly lower in the presence of HM. The fractal dimension values of sludge samples were increased by the addition of HM, whilst their total surface energy values were decreased, indicating that HM reinforced the stability of the sludge structure. Analyses of the physicochemical properties of different sludge samples revealed that HM enhanced the structural stability of sludge organic substances and restricted its organic solubility by interacting with the biopolymers to form a dense granular aggregate, thereby reducing the random-coil degree of extracellular organic substances and its active sites for enzymes, which suggested that HM could inhibit AD by changing the sludge structure. It was further confirmed by the biochemical methane potential (BMP) assay process. The BMP tests and corresponding kinetic analyses revealed that HM can restrict the potentials of sludge organic solubilisation , hydrolysis and acidification processes, but not necessarily the rates of these processes by enhancing the structural stability of high molecular weight readily biodegradable organic matter (RBOM) and restricting the mobility of low molecular weight RBOM (i.e., hydrolysis products). These findings can enrich understanding of the AD of sludge and may thus aid in the development of more effective methods to improve sludge treatment .
研究领域:
环境科学
·
微生物学
·
污水处理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）