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Removal Behavior of Typical Micropollutants in Membrane Bioreactor Process by Different Temperature

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SSRN 2023年

作者： Wang, Qiaoying Zheng, Wenjia Wang, Yan Zhang, Tong Zhou, Zhen Wu, Zhichao State Key Laboratory of Pollution Control and Resource Reuse Shanghai Institute of Pollution Control and Ecological Security College of Environmental Science and Engineering Tongji University Shanghai200092 China College of Environmental and Chemical Engineering Shanghai Institute of Pollution Control and Ecological Security Shanghai University of Electric Power Shanghai200090 China

In this study, the removal efficiency and mechanism of 8 kinds of typical micropollutants by membrane bioreactor (MBR) at different temperatures (15, 25 and 35 °C) were investigated. MBR exhibited the high removal rate (> 85%) for 3 kinds of industrial synthetic organic micropollutants (i.e. bisphenol A (BPA), 4-tert-octylphenol (TB) and 4-n-nonylphenol (NP)) with similar functional groups, structures and high hydrophobicity (Log D > 3.2). However, the removal rates of ibuprofen (IBU), carbamazepine (CBZ) and sulfamethoxazole (SMX) with pharmaceutical activity showed great discrepancy (i.e. 93%, 14.2% and 29%, respectively), while that of pesticides (i.e. acetochlor (Ac) and 2,4-dichlorophenoxy acetic acid (2,4-D) were both lower than 10%. Operating temperature played a significant role in microbial growth and activities. High temperature (35 °C) led to a decreased removal efficiency for most of hydrophobic organic micropollutants, and was also not conducive for refractory CBZ due to the temperature *** lower temperature (15 °C), a large amount of exopolysaccharides and proteins were released by microorganisms, which caused the inhibited microbial activity, poor flocculation and sedimentation, resulting in the polysaccharide-type membrane fouling. It was proved that dominant microbial degradation and auxiliary adsorption were the main mechanisms for micropollutant removal in MBR system. Therefore, 25 °C was most conductive for micropollutant removal due to the high activity sludge so as to enhance microbial adsorption and degradation. © 2023, The Authors. All rights reserved.

关键词： Bioreactors

Fast Complete Reduction of Chlorite to Chloride from Drinking Water in Al(Iii)/Sulfite System: Kinetics, Mechanisms, and Applications

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SSRN 2024年

作者： Ji, Xingli Yu, Shuili Hou, Li-An Xu, Ying Gao, Menghong Zhang, Wei Xiao, Qi Xi’an High-Tech Institute China State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and Engineering Tongji University Shanghai200092 China Shanghai Institute of Pollution Control and Ecological Security Shanghai200092 China Department of Civil Engineering The University of Hong Kong 999077 Hong Kong

Advanced reduction processes (ARPs) hold the potential for fast reducing chlorite (ClO2‒), a harmful by-product of chlorine dioxide (ClO2) disinfection. In this study, we developed aluminum(III)/sulfite (Al(III)/S(IV)) ARPs for reduction of chlorite from drinking water. The Al(III)/S(IV) system exhibited a fast removal of 13.5 mg/L ClO2‒ within one min by 1.4 mg/L Al(III) and 80 mg/L S(IV), with a first-order rate constant of 0.126 ± 0.009 s-1. The removal rate constant was up to over two orders of magnitude faster than previous studies. Reduction of chlorite was further enhanced by increasing Al(III) and S(IV) dosage, and decreasing solution pH and dissolved oxygen levels. The electron paramagnetic resonance spectra and mass balance of chlorine revealed that sulfite radicals generated through HSO3‒ activation with Al3+ and Al(OH)2+ were responsible for chlorite reduction to chloride. Pathways for chlorite reduction were proposed accordingly. Moreover, the presence of organics and some anions (i.e., 0.5−1.0 mM Cl‒ and NO2‒) and cations (i.e., 0.5−1.0 mM K+ and Na+) little influenced chlorite reduction, while the addition of 0.5−1.0 mM HPO42‒, HCO3‒, Ca2+, and Mg2+ inhibited the reduction. Under realistic conditions relevant to water plants using ClO2 disinfection, >72.1% of 1.4 mg/L chlorite was reduced in one min with a lower electrical energy per order (EE/O = 1.78 ± 0.10 kWh/m3), meeting the Drinking Water Standard for both residue chlorite ( © 2024, The Authors. All rights reserved.

关键词： Rate constants

Enhancing Efficient Reclaim of Phosphorus from Simulated Urine by Magnesium-Functionalized Biochar: Adsorption Behaviors, Molecular-Level Mechanistic Explanations and its Potential Application

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SSRN 2023年

作者： Zhang, Lei Yang, Libin Chen, Jiabin Zhang, Yalei Zhou, Xuefei State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and Engineering Tongji University Shanghai200092 China Key Laboratory of Yangtze Water Environment Ministry of Education Tongji University Shanghai200092 China Shanghai Institute of Pollution Control and Ecological Security Tongji University Shanghai200092 China

Magnesium-functionalized Magnolia grandiflora Linn leaf-derived biochar (MBC) capable of efficiently reclaiming phosphorus from urine was synthesized by slow co-pyrolysis. Four adsorption kinetic and seven adsorption isotherm models were fitted to the batch adsorption and desorption experimental data, and it was found that pseudo-first-order kinetic model and multilayer model with saturation best described the phosphate-phosphorus (PO43-P) adsorption process by MBC. MBC and phosphorus-saturated MBC (P-MBC) were found to offer outstanding phosphorus adsorption and slow release properties, respectively. Based on material characterization, statistical physics, adsorption energy distribution and statistical thermodynamics, a multi-ionic, inclined orientation, entropy-driven spontaneous endothermic process of MBC on PO43-P was proposed, involving physicochemical interactions (porous filling, electrostatic attraction, ligand exchange and surface precipitation). Further, seed germination and early seedling growth experiments proved that P-MBC can be used as a slow-release fertilizer. Overall, MBC offers prospective applications as an efficient phosphorus adsorbent and then as a slow-release fertilizer. © 2023, The Authors. All rights reserved.

关键词： Magnesium

Nanoconfinement boosts affinity of hydrated zirconium oxides to arsenate: Surface complexation modeling study

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Chemosphere 2024年 349卷 140912页

作者： Shen, Pengfei Pan, Siyuan Huang, Xianfeng Zhang, Xiaolin State Key Laboratory of Pollution Control and Resource Reuse School of Environment Nanjing University Nanjing210023 China Nanjing University Nanjing210023 China National and Local Joint Engineering Research Center for Ecological Treatment Technology of Urban Water Pollution School of Life and Environmental Science Wenzhou University Wenzhou325035 China

Nanoscale hydrated zirconium oxide (HZO) holds great potential in groundwater purification due to its ability to form inner-sphere coordination with arsenate. Despite being frequently used, especially as encapsulations in host materials for practical application in water treatment, the adsorption mechanisms of solutes on HZO are not appropriately explored, in particular for arsenate adsorption. In this study, we investigated the Zr–As coordination configuration and identified the most credible Zr–As configuration using surface complexation modeling (SCM), XPS and FT-IR analysis. The corresponding intrinsic coordination constants (Kintr) values was calculated by SCM, and the nanoconfinement effects were distinguished by comparing bare HZO with the HZO nanoparticles (NPs) encapsulated inside the strongly basic anion exchanger D201. Potentiometric titration suggests that the surface Zirconium hydroxyl groups (≡ZrOH) mainly exist in protonated form (≡ZrOH2+). Batch adsorption experiments demonstrate that the D201 hosts could adsorb As(V) through ion exchange by the quaternary ammonium groups under the low ionic strength (≤0.01 M NaNO3) and at pH > 6. The nanocomposite (HZO@D201) exhibits a higher adsorption capacity in a wide range of pH (3-10) and ionic strength (0.001–0.1 M NaNO3) than bare HZO. SCM simulations reveal that the coordination configuration of diprotonated monodentate mononuclear (MM-H2) dominates at pH 3–6, while deprotonated bidentate binuclear (BB–H0) dominates at pH > 7. For each configuration, the intrinsic coordination constants (Kintr) of HZO@D201 (10−0.66 and 10−16.10, respectively) are significantly higher than those of bare HZO (10−12.24 and 10−44.42, respectively), indicating a superior chemical bonding affinity caused by nanoconfinement. The obtained Kintr values are used to predict arsenate adsorption isotherms in pH 3 and 9, and the results align with the SCM simulation outcomes. This study may offer a feasible method for investigating the n

关键词： Nanocomposites

Direct Lactic Acid Production from Household Food Waste by Lactic Acid Bacteria

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SSRN 2022年

作者： Song, Liang Liu, Shiyu Liu, Rui Yang, Donghai Dai, Xiaohu State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and Engineering Tongji University Shanghai200092 China

China is vigorously promoting garbage classification, but the treatment of classified waste, especially household food waste (HFW) remains to be studied. We aimed to analyze the comprehensive properties of classified HFW in Shanghai, then to produce lactic acid (LA), a high value-added platform molecule by inoculating lactic acid bacteria (LAB) directly. The effects of strains, temperature, sterilized or not, initial pH, inoculum size, and substrate concentration on LA production were investigated. The results showed that LA concentration of 30.25 g/L at 37 °C , pH 6.8 could be obtained by inoculating Lactobacillus rhamnosus ATCC 7469 from sterilized HFW. High inoculum size and substrate concentration resulted in high LA concentration, but not high LA yield. In addition, an average LA concentration of 26.8 g/L, LA yield of 0.20 g COD/g TCOD was obtained by repeated batch fermentation for 32 d. © 2022, The Authors. All rights reserved.

关键词： Lactic acid

Mercury transformation processes in nature: Critical knowledge gaps and perspectives for moving forward

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Journal of Environmental Sciences 2022年第9期34卷 152-165页

作者： Zhiyuan Gao Wang Zheng Yanbin Li Yurong Liu Mengjie Wu Shouying Li Ping Li Guangliang Liu Xuewu Fu Shuxiao Wang Feiyue Wang Yong Cai Xinbin Feng Baohua Gu Huan Zhong Yongguang Yin Centre for Earth Observation Science and Department of Environment and GeographyUniversity of ManitobaWinnipegMB R3T 2N2Canada Institute of Surface-Earth System Science Tianjin UniversityTianjin 300192China Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education and College of Chemistry and Chemical EngineeringOcean University of ChinaQingdao 266100China State Key Laboratory of Agricultural Microbiology Huazhong Agricultural UniversityWuhan 430070China School of the Environment Nanjing UniversityState Key Laboratory of Pollution Control and Resource ReuseNanjing 210023China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Department of Chemistry and Biochemistry Florida International UniversityMiamiFL 33199USA School of Environment and State Key Joint Laboratory of Environment Simulation and Pollution Control Tsinghua UniversityBeijing 100084China Environmental Sciences Division Oak Ridge National LaboratoryOak RidgeTennessee 37831USA Environmental and Life Sciences Program(EnLS) Trent UniversityPeterboroughOntario K9L 0G2Canada Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China

The transformation of mercury(Hg) in the environment plays a vital role in the cycling of Hg and its risk to the ecosystem and human health. Of particular importance are Hg oxidation/reduction and methylation/demethylation processes driven or mediated by the dynamics of light, microorganisms, and organic carbon, among others. Advances in understanding those Hg transformation processes determine our capacity of projecting and mitigating Hg risk. Here, we provide a critical analysis of major knowledge gaps in our understanding of Hg transformation in nature, with perspectives on approaches moving forward. Our analysis focuses on Hg transformation processes in the environment, as well as emerging methodology in exploring these processes. Future avenues for improving the understanding of Hg transformation processes to protect ecosystem and human health are also explored.

关键词： Mercury oxidation reduction methylation demethylation isotope fractionation

Sewer sediment adhesion degeneration and gelatinous biopolymer deconstruction by structural cation chelation and alkaline macromolecule hydrolysis for improving hydraulic erosion

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Chemosphere 2024年 356卷 141902页

作者： Lu, Jinsuo Liu, Jinxuan Li, Xingwang Zhang, Zhiqiang Wang, Sheping Pang, Heliang School of Environmental and Municipal Engineering Xi'an University of Architecture and Technology Xi'an710055 China Shaanxi Key Laboratory of Environmental Engineering Xi'an710055 China State Key Laboratory of Pollution Control and Resource Reuse Shanghai200092 China Xi ‘an Municipal Design and Research Institute Co. LTD Xi'an710055 China

Sediment siltation has been regarded as the serious challenge in sewer system, which dominantly root in the gelatinous extracellular polymeric substance (EPS) structure and cohesive ability. Considering the crucial roles of divalent cation bridging and macromolecular biopolymer winding in sediment EPS formation and adhesive behavior, an innovative combination strategy of sodium pyrophosphate (SP)-mediated divalent cation chelation and alkaline biopolymer hydrolysis was developed to degenerate sediment adhesion. At the SP dosage of 0.25 g/g TS and the alkaline pH 12, the SP + pH 12 treatment triggered structural transformation of aromatic proteins (α-helix to β-turn) and functional group shifts of macromolecular biopolymers. In this case, the deconstruction and outward dissolution of gelatinous biopolymers were achievable, including proteins (tyrosine-like proteins, tryptophan-like proteins), humic acids, fulvic acids, polysaccharides and various soluble microbial products. These were identified as the major driving forces for sediment EPS matrix disintegration and bio-aggregation deflocculation. The extraction EPS content was obviously increased by 18.88 mg COD/g TS. The sediment adhesion was sensitive to EPS matrix damage and gelatinous biopolymer deconstruction, leading to considerable average adhesion degeneration to 0.98 nN with reduction rate of 78.32%. As such, the sediments could be disrupted into dispersive fragments with increased surface electronegativity and electric repulsion (up to −45.6 mV), thereby the sediment resistance to hydraulic erosion was impaired, providing feasibility for in-situ sediment floating and removal by gravity sewage flow in sewer. © 2024

关键词： Adhesion

Investigation on the role of ·OH for BPA removal in coastal sediments: The important mediation of low reactivity Fe(II)

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Chemosphere 2024年 353卷 141575页

作者： Yue, Jingyuan Hu, Xiaojin Xie, Huijun Hu, Zhen Wu, Haiming Zhang, Jian Sun, Bo Wang, Lushan Environment Research Institute Shandong University Qingdao266237 China Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse Shandong Key Laboratory of Environmental Processes and Health School of Environmental Science and Engineering Shandong University Qingdao266237 China State Key Laboratory of Microbial Technology Institute of Microbial Technology Shandong University Shandong Qingdao266237 China

Bisphenol A (BPA) in seawater tends to be deposited in coastal sediments. However, its degradation under tidal oscillations has not been explored comprehensively. Hydroxyl radicals (·OH) can be generated through Fe cycling under redox oscillations, which have a strong oxidizing capacity. This study focused on the contribution of Fe-mediated production of ·OH in BPA degradation under darkness. The removal of BPA was investigated by reoxygenating six natural coastal sediments, and three redox cycles were applied to prove the sustainability of the process. The importance of low reactivity Fe(II) in the production of ·OH was investigated, specifically, Fe(II) with carbonate and Fe(II) within goethite, hematite and magnetite. The degradation efficiency of BPA during reoxygenation of sediments was 76.78–94.82%, and the contribution of ·OH ranged from 36.74% to 74.51%. The path coefficient of ·OH on BPA degradation reached 0.6985 and the indirect effect of low reactivity Fe(II) on BPA degradation by mediating ·OH production reached 0.5240 obtained via partial least squares path modeling (PLS-PM). This study emphasizes the importance of low reactivity Fe(II) in ·OH production and provides a new perspective for the role of tidal-induced ·OH on the fate of refractory organic pollutants under darkness. © 2024 Elsevier Ltd

关键词： Degradation

The elevation of salinity above 1% deteriorated nitrification performance and reshaped nitrifier community of an MBR: An often overlooked factor in the treatment of high-strength ammonium wastewater

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Chemosphere 2023年第1期335卷 139072页

作者： Zou, Jie Zhang, Kaoming Wang, Sifang Li, Mingji Wang, Zijia Wang, Shu Li, Yangkai Deng, Yuepeng Li, Xiuying Wang, Depeng Yang, Yunhua Feng, Yiping Hu, Chun Wang, Zhu Institute of Environmental Research at Greater Bay Key Laboratory for Water Quality and Conservation of the Pearl River Delta Ministry of Education Guangzhou University Guangzhou510006 China State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University Nanjing210023 China Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control School of Environmental Science and Engineering Institute of Environmental Health and Pollution Control Guangdong University of Technology Guangzhou510006 China

The effects of synchronous variations of influent salinity with the elevation of NH4+-N concentration on nitrification performance and microbial community structure of bioreactor are often ignored. In this study, we investigated the dynamic response of nitrifying activated sludge to synchronously increased salinity and ammonia loading rate (ALR) in a nitrification membrane bioreactor (MBR). We found that the increase in influent salinity above 1% (from 0.91 to 1.32%) led to the deterioration of the nitrification performance of the MBR. The combined inhibition effect of salinity (1.32%), free ammonia (FA, an average of 1.37 mg/L), and free nitrous acid (FNA, an average of 0.155 mg/L) on nitrite-oxidizing bacteria (NOB) resulted in long-term (35 days) nitrite accumulation. The further increase of salinity and ALR exhibited little influence on the nitrification performance of MBR after the activated sludge had adapted to high salinity (>1%), effective nitrification performance was achieved at high ALR up to 1.71 kg NH4+-N/m3·d and high salinity (2.13%). The microbial analysis showed that the elevated salinity and accumulation of FNA reshaped the microbial community structure of ammonia-oxidizing bacteria (AOB) and NOB. The dominant species of AOB and NOB shifted from the salinity-resistant species Nitrosomonas aestuarii to the species Nitrosomonas mobilis with dual resistant to salinity and FNA, and from non-salinity-resistant species Candidatus Nitrospira defluvii to salinity-resistant species Nitrobacter winogradskyi and Nitrospira marina, respectively. Therefore, the salinity of 1% may be a critical level for the nitrification performance and the shift in the nitrifier community of activated sludge without salinity acclimation. © 2023 Elsevier Ltd

关键词： Bioreactors