SCIENCE OF THE TOTAL ENVIRONMENT
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2023
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IF 9.8
Longfei Xie,Le Gou,Donghai Xu,Krzysztof Kapusta,Liyi Dai,Yuanyuan Wang
Nitrogen (N) in sewage sludge (SS) should be reduced if it is to be used to produce clean solid fuels. However, the N transformation during hydrothermal carbonization (HTC) of SS is not yet fully understood. Since the composition of SS is complex, it is wise to study a model compound, which should have typical functional groups of organic components. Hence, in this study, six model components (protein, lipid, cellulose, hemicellulose, humic acid , and lignin) representing the main organic components in SS were mixed with SS and treated at 150–270 °C for 1 h. The influence of the organic component and reaction temperature on hydrochar yield, hydrochar characterization, and N distribution in the products was investigated. Except for proteins and lipids, all the other components were found to contribute to the N content and aromatization of the hydrochar. Humus shows the best comprehensive performance in terms of both reducing the N content and increasing the aromaticity. The strongest effects of hemicellulose and cellulose on N retention in hydrochar are found to occur at 210 °C and 240 °C, respectively. The N retention caused by lignin is correlated with the Mannich reaction at 240 °C, while humus significantly promotes N transformation at 240 °C. For carbohydrates, lignin, and humus, the temperatures required for increasing the N content and aromaticity maintain a high degree of consistency. Although protein pulls down the energy recovery (ER) and yield of the hydrochar, observations indicate that it favors the carbonization process. This finding can be used for estimating the N content and quality of hydrochar and provides references for future research targeting the upgrading of hydrochar.
研究领域:
环境科学
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能源科学
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Yingying Cai,Aikelaimu Aihemaiti,Yiping Su,Yongqi Sun,Xin Sun,Heng Li,Kezhen Chen,Xuehua Shen,Feng Yan,Fan Qu,Heijin Chen,Zuotai Zhang
In this study, the CO 2 -looping system was firstly attempted to build for exploring the effect of calcium-based (Ca-based) additives on pyrolytic characteristics and products in co-pyrolysis of sewage sludge (SS) and biomass. Then, an innovation method for the consumption of CO 2 (CP CO2 ) evaluation was proposed and carried out in the CO 2 -looping system, in which it was evaluated based on the syngas volume and CO 2 proportion. The results revealed that the addition of CaO and Ca(OH) 2 could significantly improve CP CO2 by 21.2% in the co-pyrolysis of 500 ℃, while the CaCO 3 addition decreased the CP CO2 by 1.0%. Besides, the co-pyrolysis temperature more than 700 ℃ would play more significant role on the CP CO2 than the addition of Ca-based additives. Then the effect of Ca-based types on biochar characteristics was also identified accompanied by the bio-oil composition. Results showed that the CaO and Ca(OH) 2 additives not only increased biochar mass and pH, but also enhanced the dissolved organic carbon content and the variety of dissolved organic matter, and reduced the total HMs content. Meanwhile, it was 15 types of components that was identified in bio-oil by NIST mass spectral library, found that the intensity of heptadecanenitrile and estra-1,3,5(10)-trien-17 beta-ol was influenced by Ca-based additives. Moreover, the CaO and Ca(OH) 2 played important roles for improving the CP CO2 in the CO 2 -looping system, which was further verified by Fact Sage. Finally, the mechanism for the Ca-based additives on CP CO2 was proposed at different co-pyrolysis temperatures. These findings can widen paths for biochar application and development of CO 2 capture materials.
研究领域:
环境科学
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化学工程
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL TECHNOLOGY
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2021
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IF 3.247
Yan-Qin Yang,Min-Hua Cui,Jian-Chao Guo,Jing-Jing Du,Zhi-Yong Zheng,He Liu
In this study, biochars were produced by co-pyrolysis of rice husk and sewage sludge, the environmental risk of heavy metal (Pd and Cd) in the biochars was assessed. Co-pyrolysis resulted in a lower yield but a higher C content compared with sewage sludge pyrolysis alone, the relative contents of Pb and Cd in biochars were declined. Co-pyrolysis process transformed the bioavailable heavy metals into stable speciation. The environmental risk assessment codes of Pb and Cd were reduced by 1–2 grades. The co-pyrolysis technology provides a feasible method for the safe disposal of heavy metal-contaminated sewage sludge.
研究领域:
环境科学
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土壤学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
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2022
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IF 7.968
Chengcheng Shen,Li Gu,Sihao Chen,Yajuan Jiang,Peng Huang,Heng Li,Huayang Yu,Dong Xia
Effective utilization and resourcelization of sewage sludge into value-added by-products and insights into its environmental impacts during the fabrication process are urgent tasks to be tackled. Here, we adopt FeCl 3 to activate and functionalize sewage sludge to form FeCl 3 -activated biochars, which exhibited high adsorption capabilities for the treatment of toxic As(III) and Cr(VI) containing wastewaters. Kinetic studies suggested that the adsorption of As(III) and Cr(VI) species onto the biochar surface was attributed to physisorption and chemosorption, respectively. Equilibrium was reached after 3 h for the adsorption of Cr(VI), and slightly slower for that of As(III). Additionally, the structural stability of the adsorbent was maintained even in wastewater with high acidity (pH = 1), as corroborated by microscopic observations. Structural characterization of the adsorbents after adsorption showed that the excellent adsorption performance originated from adsorptive functionalities of the surface functional groups and the active Fe 3 O 4 particles forming Fe-O-As(III)/Fe-O-Cr(VI) complexes with the As(III)/Cr(VI) adsorbates. Evaluation via the green degree method demonstrated that transforming sewage sludge into biochar exerts very low impacts on the environment. Hence, this work offers a green alternative to convert the hazardous sewage sludge into value-added biochar materials, which can be further exploited as supporting frameworks for multifunctional catalysts or expanded to be investigated in reducing carbon footprints and energy conversion areas.
研究领域:
环境科学
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废物管理
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水处理
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材料科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2025
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IF 7.2
Yanjun Liu,Zhengju Lyu,Sheng Wang,Yanfeng Zhang,Junbo Wang,Zhuowen Chen,Jianbing Wang
Biomass treatment and efficient energy recovery pose formidable challenges in solid waste management. The activation and functionalization of biochar-based catalysts (BC) derived from the co-pyrolysis of municipal sewage sludge (MSS) and cotton stalks (CS) were systematically investigated. These catalysts were then reintroduced into the same co-pyrolysis system of MSS and CS to evaluate their role in enhancing hydrogen-rich gas production efficiency through in-situ catalytic upgrading. The response surface methodology (RSM) was used to identify the best co-pyrolyzed biochar preparation conditions that would obtain the maximum specific surface area (SSA). BC with the maximum SSA was prepared at a pyrolysis temperature of 900°C, a CS-to-MSS mass ratio of 6:4, and a residence time of 66 min. Potassium hydroxide (KOH), calcium nitrate anhydrous (Ca(NO 3 ) 2 ), and nickel nitrate (Ni(NO 3 ) 2 ) were used for the activation and functionalization of BC. Ni/Ca@KWBC with 30% active components (15% Ni and 15% Ca) loading was the best catalyst with the highest H 2 yield (5.03 mmol/g) and production rate (20.30%). After reuse of the catalyst for five cycles, no serious reduction of H 2 yield is found. Ni primarily promoted reforming reactions that directly increased the H 2 yield, such as the water–gas shift reaction and the steam–methane reforming reaction. Ca adsorbed CO 2 and reduced the activation energy of the reaction, assisting in shifting the equilibrium of the water–gas shift reaction toward H 2 generation. This closed-loop system uniquely repurposes biochar—a traditional low-value byproduct—as a catalyst, offering a novel pathway for integrated waste management and energy production.
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2025
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IF 7.2
Le Gou,Zhentao Ping,Liyi Dai,Yuanyuan Wang
Organic acids are commonly used additives in the hydrothermal carbonization (HTC) of sewage sludge (SS). Previous studies have demonstrated that organic acids can effectively increase the carbon content of hydrochar, reduce its nitrogen content, and improve its combustion performance. Due to significant differences in molecular structure and chemical reactivity among organic acids with varying carbon chain lengths, they may exert distinct influences on hydrochar yield, carbon content, and combustion behavior. However, there remains a lack of systematic research on the effects of organic acids with varying carbon chain lengths during the HTC process. In this study, an orthogonal experimental design was employed to investigate the influence of C1 to C9 organic acids on the carbon content of hydrochar under various temperatures (170–230 °C) and concentrations (0.1–0.5 mol/L). The results showed that as the carbon chain length increased, organic acids were more likely to incorporate into the hydrochar structure through chemical reactions, resulting in a gradual increase in both carbon content and calorific value. Furthermore, the addition of long-chain organic acids led to a reduction in nitrogen content and enhancement of the combustion characteristics of the hydrochar. Meanwhile, long-chain organic acids were also beneficial for the recovery of nutrients from the aqueous phase. These findings provide a systematic reference for improving hydrochar quality and promoting aqueous phase resource recovery in the HTC of SS using organic acids.
研究领域:
环境工程
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能源工程
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化学工程
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废弃物管理
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Jishao Jiang,Huilin Cui,Zhuyu Tang,Shipeng Wang,Ke Cheng,Chunyan Zhang,Tonghuan Yu,Jinghua Lv,Fuqiang Yu,Dong Liu
This study investigates the effects of biochar, laccase, and their combined application on nitrogen transformation, the degradation of sucralose (SUC) and acesulfame (ACE), and the dynamics of bacterial communities during sewage sludge composting. The results indicated that NH 3 emissions were reduced by 41.2 %, 17.5%, and 40.8 % in the biochar, laccase, and biochar-laccase treatments, respectively, compared to the control. Meanwhile, N 2 O emissions decreased significantly by 26.8 % and 16.0 % for the biochar and biochar-laccase treatments, respectively, but increased by 8.1 % for the laccase treatment. Additionally, the biochar, laccase, and biochar-laccase treatments enhanced the degradation of SUC and ACE by 36.6–68.3 % and 49.2–69.8 %, relative to the control, respectively. Network analysis showed that the additive-treatment enhanced the cooperation within bacterial communities, and solidified artificial sweeteners degradation, especially under biochar-laccase application. Phylogenetic investigation of communities by reconstruction of unobserved states further indicated that biochar, laccase, biochar-laccase treatment increased enzymes associated with the degradations of organic matter and artificial sweeteners. In conclusion, it suggested that a combined addition of biochar and laccase was an effectively way to reduce nitrogen loss and promote artificial sweeteners degradations during sewage sludge composting.
研究领域:
环境科学
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微生物学
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废物管理
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生物技术
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
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2021
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IF 11.236
Jinxi Feng,Tiantian Zhang,Jingxiang Sun,Jinzhu Zhu,Wen Yan,Shuanghong Tian,Ya Xiong
Piezoelectric effect was firstly employed to improve dewatering efficiency of sludge. It was found that the piezoelectric effect could be driven directly by the pressure of pressure filtration process, without any additional energy. This piezo-dewatering process coupled piezoelectric effect with pressure filtration could efficiently remove moisture of sludge. Under 0.6 MPa for 2 h, moisture content (MC) and weight of sludge could be reduced to 63.9% and 3.2 g from 96.7% and 50 g by the piezo-dewatering process with 0.45 g t -BaTiO 3 . This piezo-dewatering efficiency was much higher than that of usual conditioning-pressure filtrations using CaO, FeCl 3 or polyacrylamide (PAM) as the conditioners. And the piezo-dewatering process assisted by PAM could further decrease MC and weight of the sludge to 54.9% and 2.1 g, correspondingly, which complied to the advanced dewatering requirement (MC < 60%). The favorable piezo-dewatering efficiency was contributed to the piezo-catalytic oxidation and the electric role of remnant piezo-field. The finding of this piezo-dewatering mechanism offered an inspiring look at developing the emerging dewatering technology.
研究领域:
环境工程
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废物管理
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SUPERCRITICAL FLUIDS
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2018
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IF 3.122
Chenyu Wang,Wei Zhu,Cheng Chen,Hao Zhang,Naixi Lin,Ying Su
Dewatered sewage sludge with different moisture contents was treated with a nickel catalyst in supercritical water in a batch quartz tube micro-reactor at different temperatures and reaction times. The catalytic activity of the nickel wire catalyst was investigated. Because of the gradual deactivation of the catalyst, the hydrogen yield decreased by 8–72% after five catalytic cycles. The temperature has the largest influence on the deactivation rate of the nickel catalyst. The decline rate of the hydrogen yield decreased from 67% to 8% when the temperature was increased from 400 °C to 500 °C. SEM, EDS and TPO were used to characterize the spent catalyst. The results showed that the deactivation of the nickel catalyst is caused by the deposition of char/coke on the catalyst surface. Finally, the relationship between the reaction conditions and catalyst deactivation was investigated from the viewpoint of the organic matter degradation pathway.
研究领域:
环境工程
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化学工程
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催化
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废物管理
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
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2020
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IF 7.246
Liping Wang,Yuzhi Chang,Xuejing Zhang,Fan Yang,Yao Li,Xinran Yang,Shaogang Dong
Hydrothermal carbonization has proven to be an effective method to convert sewage sludge into solid carbon-rich hydrochar , of which the high ash content is generally regarded as limiting factor for energy-related potential application. Hydrothermal co-carbonization of sewage sludge and high concentration phenolic wastewater was firstly investigated in this study as a scenario for production of clean solid biofuel with increased calorific value and decreased ash content, by means of polycondensation reactions between phenols and highly reactive intermediates of biopolymers in sewage sludge. Results showed that addition of phenolic wastewater into sewage sludge led to a substantial increase of hydrochar yield (1.83–31.11%) and higher heating value (1.01–10.01%) and a remarkable decrease of ash content (1.39–25.68%). The reaction temperature and residence time had a complicated impact on the contribution of phenol to hydrochar production. An increase in phenol mixing ratio was beneficial to the improvement of mass yield and higher heating value but showed a less influence on the reduction of ash content. The synergistic effects between phenols and sewage sludge on the production of solid biofuel were closely related to the phenolic species, which followed the order in the aspects of hydrochar yield increase and ash content decrease: phloroglucinol > p -nitrophenol > m -cresol > phenol. The changes of phenols content in liquid phase and variations of functional groups in hydrochars implied that phenols interacted with sewage sludge and incorporated into hydrochars during the hydrothermal co-carbonization. TG-DSC confirmed the improved combustion reactivity of the phenols-sludge-derived hydrochars.
研究领域:
环境科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
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2021
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IF 9.297
Zhihui Pan,Haoyong Guo,Tingjian Huang,Gang Wen,Fangshu Qu,Junguo He,Huarong Yu
In this study, a novel and environmentally friendly technology for sludge incineration ash disposal was developed. We proposed to enhance the performance of thermo-sensitive hydrogel as draw agent for forward osmosis (FO) application by loading sewage sludge ash (SSA). The effect of SSA contents on the swelling and deswelling properties and FO performance of the hydrogels was evaluated. Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and diffusion model were applied to characterize a series of hydrogels with various SSA contents (0–4.5 wt%). The results showed that as the SSA increased, the swelling ratio of hydrogel and the water flux of SSA-hydrogel-based FO increased initially and then declined. This was due to the combined effects of hydrogen bonding and high-density crosslinking within the hydrogels. In addition, the water diffusion mechanism of all hydrogels was super Case II diffusion type. Furthermore, the SSA-loaded hydrogels not only had excellent swelling property but also exhibited good deswelling performance (water recovery ratios of them were almost 90% at 60 °C water bath for 5 min). Moreover, all hydrogels in this study showed promising reusability with almost no flux drop in four consecutive FO permeation-regeneration cycles.
研究领域:
环境科学
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材料科学
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水处理技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
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IF 14.224
Wan Yang,Chen Cai,Rui Wang,Xiaohu Dai
Wide commercial applications of antimicrobial quaternary ammonium compounds (QACs) inevitably lead to the release into wastewater and enrichment in sewage sludge . This study evaluated the impacts of levels and structures of QACs on sewage sludge properties, microbial community , and methane production during anaerobic digestion . Methane production was stimulated or not affected at low QACs concentrations, but significantly inhibited at high QACs concentrations. Compared with benzyl and alkyltrimethyl QACs, dialkyl QACs showed least toxicity on digestion performance. Meanwhile, microbial community analysis indicated that shifts in bacterial communities mainly depended on QACs doses, but the archaeal communities were affected by both QACs doses and types. The dominant methanogenic pathway shifted from acetotrophic/methylotrophic methanogens to mixotrophic methanogens by low levels of benzyl and alkyltrimethyl QACs but not dialkyl QACs, and further to hydrogenotrophic methanogens at high QACs concentration. Mechanism exploration revealed that the presence of QACs promoted sludge solubilization by the integrated effects of cell lysis, electric neutralization, and hydrophobicity improvement, but inhibited methanogenesis due to the accumulation of volatile fatty acids and susceptibility of methanogens to QACs. These findings provided a reference for potential impacts of different QACs on sludge biological treatment, which had implications for the use and selection of QACs disinfectants.
研究领域:
环境工程
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微生物学
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废物管理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）