BIORESOURCE TECHNOLOGY
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2019
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IF 6.669
Jiehui Ren,Wen Cheng,Tian Wan,Min Wang,Ting Meng,Taotao Lv
In this study, the compositional characteristics of extracellular polymeric substances (EPS) were systematically explored to reveal their relationship with microbial community under different conditions in an up-flow biological aerated filter reactor. The aeration rates had a significant positive correlation (0.898 ≤ R ≤ 0.979) with the tightly bound (TB)-EPS contents, but basically showed an opposite trend (R < −0.631) with the loosely bound (LB)-EPS. Moreover, the filter medium heights also affected EPS distribution. The microbial biofilm produced more LB-EPS and TB-EPS to withdraw from the extreme environment. Five fluorescent substances were identified in the EPS by EEM-PARAFAC modeling; namely, two protein-like components (protein-like C1 and tryptophan-like C2) and three humic-like components (UVA marine humic-like C3, hydrophobic humic acid-like C4, and humic acid-like C5). Under different conditions, the relative abundance of Proteobacteria and Nitrospirae had a significant positive correlation with C5 and C4, respectively. These results demonstrated that microbial community distribution could affect EPS composition.
研究领域:
环境工程
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微生物学
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DOI
PubMed
高影响因子
Environmental Chemistry Letters
·
2022
·Vol. 20
·期 4
·2243-2251
·
IF 13.615
Zhu Guocheng,Chen Junming,Zhang Shanshan,Zhao Zilong,Luo Huihao,Hursthouse Andrew S.,Wan Peng,Fan Gongduan
Black-odorous waters are an increasingly common phenomenon characterized by excessive levels of nutrients, the formation of metal sufide precipitates, volatile sulfurous compounds, low dissolved oxygen and high chemical oxygen demand. Black-odorous waters frequently occur in lake and river systems where inputs have restricted circulation. The key remediation issue is the removal of nitrogen and phosphorus. Here, we present a novel aeration-adsorption system using fiber balls and we study treatment parameters and removal mechanism. Kinetics and changes of the solid phase were followed using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. Results show complete removal of ammonia N, initially at 31 mg/L, and 92.8% removal of total nitrogen, initially at 29 mg/L, after a 24 h reaction time at pH 9.67. At pH 5.67 and 9.67, total phosphorus and phosphate could be significantly reduced by 90–92% at 3.2–5.2 mg/L after 24 h. Treatment met China’s integrated wastewater discharge standards, demonstrating an effective and robust treatment capability. First-order and second-order kinetic models provided a good fit to the treatment data, indicating physical and chemical adsorption were involved in the treatment reactions. The reaction mechanism involved hydrogen substitution and binding to oxygen. These results present a cost effective and robust approach for the removal of N and P from black, odorous water, providing opportunity to abate environmental contamination.
研究领域:
环境工程
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水污染治理
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生态修复
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环境化学
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DOI
高影响因子
Catalysts
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2022
·Vol. 12
·期 7
·711
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IF 4.501
Zhijie Zheng,Julin Yuan,Xinwei Jiang,Gang Han,Yufang Tao,Xiaogang Wu
Ultraviolet photolysis (UVC, 254 nm) was coupled with an electrochemical oxidation process to degrade three kinds of veterinary sulfonamide (sulfamethazine [SMZ] tablets, sulfamonomethoxine [SMM] tablets, and compound sulfamethoxazole [SMX] tablets). The treatment was applied using a flat ceramic microfiltration membrane to study the effects of photocatalysts. The effectiveness of degradation of the three sulfonamides was evaluated under different conditions. Dissolved oxygen was provided via aeration, but this resulted in a large decrease in the degradation effectiveness due to the inhibition of free chlorine electrogeneration. The photocatalysts had no promotional effect on sulfonamide removal from wastewater due to reduced UV penetration. Because of the different distribution coefficients of sulfonamides, UV irradiation had different effects on different sulfonamide species. For SMZ and SMM, anionic species exhibited a higher degradation rate, whereas for SMX, degradation was most effective for neutral species. In addition, the free chlorine yield increased as the pH increased. Free chlorine conversion reactions occurred under UV irradiation, with the reactions possibly restrained by sulfonamides. Reactive chlorine species promoted SMM degradation. Compared to UV irradiation or electrochemical oxidation alone, the UV/in-situ electrochemical oxidation process was more effective and is suitable for treating real wastewater under various environmental pH levels.Keywords:ultraviolet photolysis;in-situ electrochemical oxidation;sulfonamides;aeration
研究领域:
环境科学
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水处理工程
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DOI
高影响因子
Journal of Water Process Engineering
·
2020
·
IF 3.465
Zhiling Ma,Qunpeng Jia,Yanzhe Shi,Xiaofei Duan,Bing Han
TXP-10 is a commercial member of alkylphenol polyethoxylate surfactant family that is widely adopted as emulsifier, detergent and dispersing agent in agriculture and industry. However, it has adverse effects on environmental and public health due to the risk of eutrophication, oestrogenic activities and anti-precipitation properties. Here, we evaluated critical parameters and addressed the mechanism of aeration-assisted photodegradation of TXP-10 by using TiO 2 particulates as model photocatalysts. It was found that O 2 aeration could significantly enhance photocatalytic degradation efficiencies with a high synergetic index of 3.30 at an optimum rutile composition of 90 wt.%. Trapping experiments and superoxide radical quantification suggest two parallel mechanism pathways (O 2 -sensitive and -insensitive) dependent on phase composition of photocatalyst and irradiation intensity. Furthermore, the anti-precipitation property of TXP-10 solution during photocatalysis was evaluated and correlated to transformation of hydrophobic groups to hydrophilic derivatives. This work would gain important enlightenment into the mechanism of synergistic effect of aeration-assisted photocatalysis and its essential role in the environmental remediation.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
International Journal of Environmental Research and Public Health
·
2021
·Vol. 18
·期 7
·3633
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IF 3.39
Qianqian Lu,Nannan Zhang,Chen Chen,Miao Zhang,Dehua Zhao,Shuqing An
Lab-scale simulated biofilm reactors, including aerated reactors disturbed by short-term aeration interruption (AE-D) and non-aerated reactors disturbed by short-term aeration (AN-D), were established to study the stable-state (SS) formation and recovery after disturbance for nitrogen transformation in terms of dissolved oxygen (DO), removal efficiency (RE) of NH4+-N and NO3−-N and activity of key nitrogen-cycle functional genesamoA andnirS (RNA level abundance, per ball). SS formation and recovery of DO were completed in 0.56–7.75 h after transition between aeration (Ae) and aeration stop (As). In terms of pollutant REs, new temporary SS formation required 30.7–52.3 h after Ae and As interruptions, and seven-day Ae/As interruptions required 5.0% to 115.5% longer recovery times compared to one-day interruptions in AE-D and AN-D systems. According toamoA activity, 60.8 h were required in AE-D systems to establish new temporary SS after As interruptions, and RNAamoA copies (copy number/microliter) decreased 88.5%, while 287.2 h were required in AN-D systems, and RNAamoA copies (copy number/microliter) increased 36.4 times. FornirS activity, 75.2–85.8 h were required to establish new SSs after Ae and As interruptions. The results suggested that new temporary SS formation and recovery in terms of DO, pollutant REs andamoA andnirS gene activities could be modelled by logistic functions. It is concluded that temporary SS formation and recovery after Ae and As interruptions occurred at asynchronous rates in terms of DO, pollutant REs andamoA andnirS gene activities. Because of DO fluctuations, the quantitative relationship between gene activity and pollutant RE remains a challenge.Keywords:simulated biofilm reactor;stable state;nitrogen cycle;dissolved oxygen;gene activity
研究领域:
环境工程
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微生物学
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水处理
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DOI
PubMed
高影响因子
Membranes
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2023
·Vol. 13
·期 4
·443
·
IF 4.2
Xinqiang Xu,Hua Zhang,Jiang Jin
A novel approach to evaporate brine wastewater using a ceramic aeration membrane was proposed. A high-porosity ceramic membrane was selected as the aeration membrane and was modified with hydrophobic modifiers to avoid undesired surface wetting. The water contact angle of the ceramic aeration membrane reached 130° after hydrophobic modification. The hydrophobic ceramic aeration membrane showed excellent operational stability (up to 100 h), high salinity (25 wt.%) tolerance, and excellent regeneration performance. The evaporative rate reached 98 kg m−2h−1,which could be restored by ultrasonic cleaning after the membrane fouling occurred. Furthermore, this novel approach shows great promise for practical applications toward a low cost of only 66 kW·h·m−3.Keywords:high-porosity ceramic membrane;hydrophobic modification;brine wastewater;aeration evaporation
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2025
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IF 11.3
Zi-Chen Yang,Lu Peng,Zi-Bo Jing,Wen-Long Wang,Han-Ying Cai,Yi-Qing Jiang,Long-Di Li,Bei Ye,Qian-Yuan Wu
Ozone has been widely applied in water disinfection because of its high oxidation potential (2.07 V). However, slow ozone gas–liquid mass transfer results in high ozone requirements and operating costs. Micro-bubble aeration can effectively increase the ozone mass transfer efficiency while reducing ozone dose. Here, we used a ceramic ultrafiltration membrane for ozone micro-bubble aeration. The disinfection performance and mechanism of ozone micro-bubble aeration towards pathogenic microorganisms were studied. Micro-bubble aeration reduced the total ozone dose by > 60% for 6-log inactivation of Escherichia coli and MS2 coliphage. It also improved the disinfection efficiencies for Gram-positive bacteria by 3-log. Both ozone and • OH oxidation was enhanced via micro-bubble aeration because of efficient gas–liquid transfer. The equilibrium aquatic ozone concentration increased by 1.38 times and the • OH yield increased by 2.40 times compared with those with milli-bubble aeration. Consequently, ozone micro-bubble aeration caused severe membrane damage to bacterial cells and fragmented the bacterial DNA, which caused a rapid decrease in the bacterial metabolic activity (> 80%). This study demonstrates that ozone micro-bubble aeration can boost broad spectrum disinfection and effectively reduce the ozone dose, which will facilitate the application of ozonation with a lower cost and reduced environmental impact.
研究领域:
环境科学
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微生物学
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产品关联
DOI
PubMed
高影响因子
Journal of Water Process Engineering
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2025
·
IF 6.7
Linjun Wu,Huan Li,Yuexi Zhou,Zhiqiang Shen,Jiane Zuo
This research evaluated the efficacy of self-sustaining alkalinity driven gas permeable membrane (SSAD-GPM) in ammonia recovery under low-rate aeration. This research initially confirmed the role of HCO 3 − and CO 3 2− in enhancing alkalinity release and ammonia conversion. It was determined that providing alkalinity through HCO 3 − necessitates the consumption of inorganic carbon (IC), and highlighting the criticality of maintaining a HCO 3 − /NH 4 + ratio exceeding 1.0 to optimize ammonia removal efficiency (>90.5 %). Alkalinity via CO 3 2− involves a two-stage hydrolysis process, consuming IC only in the second phase. Then, comparing SSAD-GPM with alkalinity addition driven GPM (AAD-GPM) for real anaerobic digestate treatment, SSAD-GPM demonstrated an initial ammonia removal efficiency of 99.1 %, which reduced to 82.8 % after 40 days of operation. In contrast, the efficiency of AAD-GPM decreased to 62.6 %. Superior anti-fouling performance of SSAD-GPM, due to aeration-induced turbulence, mitigated concentration polarization and fouling. Efficiency was restored to 98.1 % post-cleaning with tap water. Lastly, this research assessed the alkalinity consumption and cost of various ammonia removal/recovery strategies, demonstrating that SSAD-GPM can substantially lower operating costs, yielding a net profit of $0.081/kg N. These findings underscore the potential of SSAD-GPM as a cost-effective approach for treating high ammonia‑nitrogen wastewater with sufficient self-sustaining alkalinity (HCO 3 − /NH 4 + > 1.0).
研究领域:
环境科学
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污水处理
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DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2022
·
IF 4.326
Keda Zhi,Chao Yang,Yu Zheng,Runnan Zhang,Omojayogbe Toyosi E,Hong Wu,Zhongyi Jiang
Electro-Fenton is a widely used electrochemical advanced oxidation process for the treatment of refractory organic pollutants, in which O2 input is required to generate hydrogen peroxide. The aeration mode directly affects the dissolution and stability of O2 bubbles in the solution, thus the rate of degradation. Herein, membrane aeration was introduced to the electro-Fenton degradation of ciprofloxacin in which O2 was dispersed into the liquid phase in the form of microbubbles through the ceramic membrane. Microbubbles can greatly improve the gas–liquid mass transfer efficiency of unit volume O2 to obtain an ultrahigh concentration of dissolved O2 up to 46 mg/L, thus improving the reaction rate. The effects of aeration mode, applied current, membrane aperture, aeration rate, and ciprofloxacin concentration on degradation rate were studied. Compared with the conventional electro-Fenton process using plastic pipe aeration, the membrane aeration-enhanced electro-Fenton (MAEF) system achieved a significant improvement in the degradation rate, and the reaction time required to achieve a 97% degradation ratio was remarkably reduced from 4 h to 10 min. Membrane aeration is an efficient approach to facilitating heterogeneous catalysis reactions involving the gas phase.
研究领域:
环境科学
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化学工程
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水处理技术
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产品关联
DOI
高影响因子
Journal of Cleaner Production
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2020
·
IF 7.246
Hongping He,Mei Sun,Deli Wu,Guanglan Di,Xunchang Fei
Heterogeneous Fenton dominated by ·OH is limited in its application, as pre-acidification is required to maximize the generation amount and redox potential of ·OH. It is thus featured to consume resources and generate pollutants. In this study, both CuS/H 2 O 2 and Cu 2 S/H 2 O 2 are found to show better performances under close-to-neutral condition (pH 5.0 to 9.0) than acidic condition (pH 3.0) when degrading a model contaminant, sulfamethazine (SMZ), because ·OH does not play a major role in both systems. The Cu valence-dependent catalytic mechanisms are responsible for the varied kinetics between CuS/H 2 O 2 and Cu 2 S/H 2 O 2 . In CuS/H 2 O 2 , Cu(III) and 1 O 2 contribute to the SMZ degradation, and their contributions are pH-dependent. In Cu 2 S/H 2 O 2 , Cu(III) is responsible for the degradation regardless of the pH. Both systems with optimal performances under neutral condition are advantageous as pre-acidification can be avoided. In addition, air sparging induces additional 16% SMZ degradation in Cu 2 S/H 2 O 2 under acidic condition, because the sparged O 2 reacts with dissolved Cu(I). The more O 2 reacts with the dissolved Cu(I), the less generated Cu(III) is ineffectively depleted. Air sparging is readily applicable to different operations, thus its combination with Cu 2 S/H 2 O 2 potentially benefits the development of environmentally-friendly treatment process for industrial wastewater .
研究领域:
环境科学
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化学工程
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DOI
高影响因子
DESALINATION
·
2024
·
IF 8.3
Wei Zhang,Qian Xiao,Shuili Yu,Xingli Ji,Rongsheng Ning,Ying Xu,Pan Li
In this work, a bench-scale vacuum membrane distillation crystallization (VMDC) system coupled with microbubble aeration (MBA) was developed for treating high-salinity feed brine. Herein, the effect of seeding dose on membrane fouling and wetting control in the VMDC system was studied by using synthetic saturated calcium sulfate solution. The results showed that introducing gypsum seeds at a dose of 0.5 g/L effectively restricted membrane fouling and wetting. Subsequently, seeding-induced crystallization coupled with MBA was employed to investigate the control effect on membrane fouling and wetting during VMDC with simulated high-salinity feed brine treatment. As 0.5 g/L gypsum seeds were directly added at 7 h in the VMDC experiment while employing MBA, membrane fouling and wetting were effectively controlled. Finally, the mechanism behind the control of membrane fouling and wetting was elucidated during VMDC operation by integrating seeding-induced crystallization with MBA. This could be ascribed to the synergic effect of gypsum seeds and microbubbles in bulk solution. In brief, this work offers a promising approach to control membrane fouling and wetting during concentrating high-salinity wastewater by VMD.
研究领域:
环境工程
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水处理技术
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DOI
高影响因子
Materials Chemistry Frontiers
·
2019
·Vol. 3
·期 10
·2102-2109
·
IF 0
Guo-Jun Wang,Bai-Heng Wu,Zhi-Kang Xu,Ling-Shu Wan
Mussel-inspired surface modification has attracted great attention in recent years. Porous membranes with opposite surface properties play an important role in various fields such as ion rectification, unidirectional oil/water separation, and nanofiltration. In this paper, we report a spray coating method to prepare a series of single-side modified membranes. Two solutions containing dopamine and NaIO4/NaOH are alternately sprayed onto membrane surfaces. Each spray process can be finished in tens of seconds. Results indicate that this method is suitable for various substrates varying from hydrophilic to hydrophobic surfaces. By introducing charged polymers such as poly(sodium 4-styrenesulfonate) into the spray solution for co-deposition, Janus membranes with differently charged surfaces have been fabricated. Such Janus membranes can remove both positively and negatively-charged dyes, while the traditionally bulk modified membranes adsorb only one kind of the dyes. We further demonstrated that the Janus membrane with asymmetric wettability has potential in promoting bubbling efficiency while reducing the energy consumption. The proposed spray coating method is fast and effective and can be applied to different membrane materials for various applications.
研究领域:
材料科学
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环境工程
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产品关联
DOI
危险品化学品经营许可证（带存储）