Processes
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2019
·Vol. 7
·期 11
·827
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IF 1.963
Yong Li,Siyuan Zhao,Jiejie Zhang,Yang He,Jianqiang Zhang,Rong Ge
The aerobic denitrifying phosphate accumulating bacteria (ADPB) use NO3−as an electron acceptor and remove nitrate by denitrification and concomitant uptake of excessive phosphorus in aerobic conditions. Activated sludge was collected from the A2O aerobic biological pool of the sewage treatment plant at Hezuo Town, Chengdu City. The candidate ADPB strains were obtained by cultivation in the enriched denitrification media, followed by repeated isolation and purification on bromothymol blue (BTB) solid plates. The obtained candidates were further screened for ADPB strains by phosphorus uptake experiment, nitrate reduction test, metachromatic granules staining, and poly-β-hydroxybutyrate (PHB) staining. The 16 sedimentation ribosome deoxyribonucleic acid (16 S rDNA) molecular technique was used to determine their taxonomy. Further, the denitrification and dephosphorization capacities of ADPB strains were ascertained through their growth characteristics in nitrogen-phosphorus-rich liquid media. The results revealed a total of 25 ADPB strains screened from the activated sludge of the A2O aerobic biological pool of the sewage treatment plant at Hezuo Town. These strains belonged to two classes, four orders, and five genera. Among them, the strain SW18NP2 was a potentially new species in theAcinetobactergenus, while the strain SW18NP24 was a potential new species in thePseudomonasgenus at the time of their characterization. TheAcinetobacterwas the dominant genus. The obtained ADPB strains demonstrated a rich diversity. The ADPB strains had significant variations in denitrification and dephosphorization capacities. Twenty-three strains exhibited a total phosphorus removal rate of above 50%, and 19 strains exhibited a total nitrogen removal rate of above 50%. The strain SW18NP2 showed the best denitrifying phosphorus removal (DPR) capacity, with a dephosphorization rate of 82.32% and a denitrification rate of 73.73%. The ADPB in the A2O aerobic biological pool of the sewage treatment plant at Hezuo Town demonstrated a rich diversity and a strong DPR capacity.Keywords:aerobic denitrifying phosphate accumulating bacteria (ADPB);diversity;denitrifying phosphorus removal
研究领域:
环境微生物学
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污水处理
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产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Hongbo Chen,Yefeng Zhou,Xiayi Hu,Ke Tian,Junfeng Zhang
Due to the widespread use of antibiotics in healthcare and livestock production , antibiotic resistance genes and residual antimicrobials would enter environment and further discharge into the municipal sewage system. The objective of this work was to explore the potential effect of chlortetracycline (CTC) on biological nutrient removal from wastewater. Thus, the effects of CTC on biological phosphorus and nitrogen removal were investigated with respect to the viability of bacteria, the activities of key metabolic enzymes, and the transformations of intermediate metabolites. Results showed that the presence of 0.1 mg·L −1 CTC did not show any impact on biological phosphorus and nitrogen removal. Nevertheless, the long-term exposure to 1 and 10 mg·L −1 CTC decreased TN removal efficiency from 77.4% to 64.1% and 53.4%, respectively. Meanwhile, the presence of 10 mg·L −1 CTC decreased the SOP removal efficiency from 96.3% to 78.1%. Mechanism studies indicated that CTC could affect the activities of reductase and the transformations of polyhydroxyalkanoates and glycogen, resulting in inhibition of denitrification and phosphorus uptake, which may be the major reason for the high level of CTC showing adverse influence on wastewater biological nutrient removal.
研究领域:
环境科学
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微生物学
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污水处理
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DOI
PubMed
高影响因子
ACS ES&T Engineering
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2021
·
IF 0
Yanyang Zhang,Bo Kong,Zhaoyang Shen,Jieshu Qian,Bingcai Pan
In situ immobilization of phosphorus (P) by using P binding agents is a facile and effective strategy for eutrophication control. Currently, the most successful commercial agent (Phoslock, a lanthanum modified bentonite, LMB) still suffers low P removal efficiency from natural waters of complex chemistry, largely due to the competitive complexation of the active La species by humic substances (HAs) and bicarbonate. Herein, we describe an attempt to address these issues by intercalating La into Mg/Fe layered double hydroxides, a pyroaurite-like anionic clay, to obtain a hybrid agent (denoted L-CMF-1.0) of phosphate capacity five times higher than that of LMB. More attractively, the binding stability and capacity of L-CMF-1.0 toward P were significantly enhanced in the presence of HAs and bicarbonate, resulting in a high La usage (P/La ratio at ∼1.30). A continuous P immobilization test in the simulated natural waters validates that the addition of L-CMF-1.0 at 0.12 g/L could result in an efficient P removal from 580 μg/L to <100 μg/L within 38 days, outperforming LMB within 10 days only under otherwise identical conditions. Such improvement results from the rational design of the agent structure, i.e., the host, not only contributes to the direct P uptake but also provides a flexible nanoshelter microenvironment to favor the specific La–P interaction under complex solution chemistry. This work is believed to shed new light on the rational design of P binding agent for enhanced eutrophication control.
研究领域:
环境科学
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水处理技术
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DOI
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2018
·Vol. 25
·期 10
·9342-9350
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IF 2.8
Hu Zhetai,Sun Peide,Han Jingyi,Wang Ruyi,Jiao Liang,Yang Pengfei,Cai Jing
Since extensive application, an increasing amount of antibiotics has been released into wastewater treatment plants. In this study, the enhanced biological phosphorus removal (EBPR) system was fed with synthetic wastewater containing erythromycin (ERY) and oxytetracycline (OTC) for 7 days to evaluate the variations of solution ortho-P (SOP), volatile fatty acid (VFA), poly-bhydroxyalkanoates (PHAs), specific oxygen uptake rater (SOUR), and microbial community in the EBPR system. The obtained results showed that the P-removal efficiency decreased to 0.0%, and at the end of the experiment, only less than 20% of the VFA could be consumed. Besides, the variable processes of P and PHAs were destroyed. Moreover, to better grasp the inhibitory mechanism of antibiotics, microbial community compositions of activated sludge sampled in all reactors were investigated by high-throughput sequencing techniques. Results of comparative and evolutionary analysis revealed that high concentrations (5 and 10 mg/L) of ERY and OTC could seriously shift microbial communities, while combined antibiotics could induce more. Additionally, Accumulibacter and Competibacter were two primary microorganisms at the genus level in the EBPR system. Accumulibacter decreased seriously for exposure to antibiotics, while Competibacter increased in all experimental reactors especially in combined antibiotics reactor.
研究领域:
环境科学
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微生物学
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DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2021
·
IF 7.963
Ligui Wu,Quantao Wei,Yingying Zhang,Yuxing Fan,Mi Li,Lingling Rong,Xiaoyu Xiao,Xiangfeng Huang,Xiaoming Zou
Many kinds of antibiotics are continuously discharged into wastewater and typically cause a great decrease in sewage treatment performance, whereas mechanisms of differences in the impacts of commonly used antibiotics on phosphate removal are still elusive. Thus, an enhanced biological phosphorus removal (EBPR) system, as an effective method of phosphate removal, was developed, and its performance in the treatment of artificial wastewater containing antibiotics at short- (8 h) and long-term (15 days) exposure was investigated. The results show that phosphorus removal was consistently inhibited by the addition of antibiotics with a significant difference (P < 0.05). To interpret the phenomena, mechanistic equations were developed, and the results indicate that for short-term tests, the difference was mainly caused by the suppression of polyhydroxyalkanoate (PHA) degradation and the activity of polyphosphate kinase (PPK), resulting in the different inhibition of the soluble orthophosphorus (SOP) uptake process. For long-term tests, the difference in SOP uptake was principally caused by the inhibition of PHA degradation and the activity of PPK, whereas the difference in SOP release resulted from the inhibition of activities of exopolyphosphatase (PPX) and adenylate kinase (ADK). Moreover, micro-mechanisms of such inhibition were identified from molecular docking and electrostatic potential.
研究领域:
环境科学
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
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2024
·
IF 8
Ruyi Wang,Juqing Lou,Jing Cai
The inhibiting effects of ciprofloxacin (CIP) on enhanced biological phosphorus removal (EBPR) were investigated with no change in reactor operation and with increased aeration rate and sludge retention time (SRT) to explore inhibition-alleviating solutions. Additionally, performance recoverability was evaluated. The results showed that the phosphorus removal efficiency in the presence of 0.002–0.092 mg/L CIP for 7 days was only 12.5%. Increasing the aeration rate relieved inhibition (33.5% phosphorus removal efficiency on Day 7), and increasing SRT slowed EBPR performance deterioration. The EBPR performance recovered from CIP inhibition and increases in the aeration rate and SRT resulted in different recovery phenomena. The maximum PO 4 3- -P release rate continued to decrease in the first 2 days of the recovery stage and then gradually increased. However, the maximum PO 4 3- -P uptake rate immediately increased at different rates among reactors, which might be attributed to variations in the microbial community structure, decreased poly-P content, and enhanced abundances of ABC transporters and quorum sensing. It was found that some microorganisms associated with phosphorus removal were more tolerant to CIP than glycogen accumulating organisms. Moreover, the increased relative abundance of the qepA gene indicated that the microorganisms in the EBPR system had strong antibiotic resistance capacity. The bacterial community structure was significantly affected by CIP and could not recover to the initial structure. The results help to provide technical support for the operation of the EBPR process in the presence of CIP and to increase the understanding of system recoverability.
研究领域:
环境工程
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微生物学
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产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
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2015
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IF 4.494
Hongjie Wang,Wengyi Dong,Ting Li,Tongzhou Liu
The performance of a BAF system configuring simultaneous chemical phosphorus precipitation in the pre-denitrification stage was examined using a continuously operated setup to treat real domestic wastewater. The effects of using no chemical, dosing sole Fe 2+ , and dosing combined Fe 2+ , PAM, and NaHCO 3 in the pre-denitrification tank were assessed by monitoring COD, nitrogen, and phosphorus removal and hydraulic headloss development in the BAF column. Though dosing sole Fe 2+ significantly enhanced phosphorus removal, it would consume alkalinity through hydrolysis and form smaller-sized sludge flocs in the pre-denitrification tank, and hence resulted in affected NH 4 + -N, insoluble COD, and SS removal in the BAF. Dosing combined Fe 2+ , PAM, and NaHCO 3 can enhance sludge flocculation to form larger flocs and compensate alkalinity consumption. It exhibited sound performance on COD, nitrogen, and phosphorus removal, and led to less frequent BAF backwashing by slowing clogging development in the BAF filter layer.
研究领域:
环境工程
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污水处理
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2020
·
IF 9.038
Kun Li,Jin Qian,Peifang Wang,Chao Wang,Bianhe Lu,Wen Jin,Xixian He,Sijing Tang,Chao Zhang,Pan Gao
The effect of nanomaterials aging, namely the transformation of comprehensive characteristics after experiencing real or complex environmental behaviors, on their ecotoxicology is still lacking. Moreover, the mechanisms by which NPs influence biological phosphorus (P) removal during sewage treatment require further elucidation. Therefore, we used both pristine and aged anatase (TiO 2 -A) and rutile (TiO 2 -R) NPs to investigate the mechanisms by which NPs affect P removal in a SBR. At 0.1 mg/L, the four types of NPs (pristine and aged) had no significant effect on sludge purification after acute (72-h) exposure under simulated sunlight. However, at 50 mg/L—regardless of the crystalline phase of the NPs—SOP and COD removal efficiency dropped steeply to approximately 42.2–82.4 % (p < 0.05) and 69.8–83.3 % (p < 0.05), respectively, especially in the pristine TiO 2 -NPs groups because of decrease of richness and diversity of genus level of PAOs and enzyme activity of both PPK and PPX, and the sluggish transformation of PHA and glycogen. Aging reduced the ability of NPs toxicity. The toxicity mechanisms of TiO 2 -NPs included lipid peroxidation and contact damage, or leakage from bacterial cytoplasmic membrane, which are closely related to photooxidation capacity and aqueous solution stability—i.e., nanoscale effects—and the impacts of aging or inclusion.
研究领域:
环境科学
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微生物学
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生态毒理学
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DOI
PubMed
高影响因子
Environmental Science-Nano
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2018
·Vol. 5
·期 12
·2936-2944
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IF 6.087
Xiaoying Zheng,Dan Lu,Yuan Zhang,Wei Chen,Mengqi Jin,Xiaoyao Shao,Mengmeng Yang
The increasing use of cerium dioxide nanoparticles (CeO2 NPs) has raised concerns about their potential environmental toxicity. Denitrifying phosphorus removal-aerobic granular sludge (DPR-AGS) is a distinct form of microbial aggregates. In this study, the phosphorus removal efficiencies, the metabolic intermediates of polyhydroxyalkanoates (PHA) and glycogen, the enzyme activities of exophosphatase (PPX) and polyphosphate kinase (PPK), and the microbial community of DPR-AGS under long-term exposure to CeO2 NPs (0 (the control), 1, and 10 mg L−1) in anaerobic/oxic/anoxic (A/O/A) sequencing batch reactors (SBRs) were investigated. The results showed that chronic toxicity caused by 10 mg L−1 CeO2 NPs resulted in increased reactive oxygen species (ROS) production and lactate dehydrogenase (LDH) release, which reached 176.32% and 237.35%, respectively, when compared with the control (100%). High-throughput sequencing showed that denitrifying-phosphorus-accumulating organisms (DPAOs) were more sensitive to CeO2 NPs than phosphorus-accumulating organisms (PAOs), which was in accordance with phosphorus transformations during one cycle. However, the abundance of Dechloromonas and Defluviicoccus increased from 4.68% and 3.08% (R0) to 9.95% and 7.06% (R10), respectively, indicating that the tolerance of glycogen-accumulating organisms to CeO2 NPs was stronger than that of PAOs, which was consistent with the transformation of the metabolic pathway from polyphosphate accumulation (PAM) to glycogen accumulation (GAM).
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
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 6
·4230-4243
·
IF 3.9
Qianyi Zhao,Qiang Geng,Guoqiang Huang
Polysilicon is widely used in the field of semiconductors and solar energy. Trichlorosilane feedstocks that are used to produce polysilicon in the mainstream production process contain PCl3 impurities that have adverse effects on the quality of the polysilicon. Traditional methods for dephosphorization cannot achieve the effect of complete removal, whereas oxidizing PCl3 to POCl3 in the presence of oxygen for removal via adsorption is a promising and appealing route for establishing a dephosphorization process; it has a high phosphorous removal rate due to the strong Lewis-base property of POCl3 in comparison with PCl3. In this work, we synthesized an active catalyst with an active interface between Au nanoparticles (NPs) and a manganese-oxide support (Mn3O4) by calcination of a corresponding composite, where Au NPs were embedded uniformly in a metal–organic framework (MOF). The catalyst shows a significantly active catalytic performance for trace PCl3 oxidation in an organic system that is an imitation of a trichlorosilane system, with a 99.13% yield of POCl3 in an 80 °C and 0.6 MPa reaction environment. The structure–performance–mechanism analysis shows that the possible reaction and catalytic mechanism is PCl3 oxidation by interface lattice oxygens, which bridge the Au NPs and the support, in a Mars van Krevelen (MvK) process; this process was promoted by the interaction between the Au NPs and Mn3O4 in terms of charge transfer and chemical potential changes. This work provides an effective way to dephosphorize trichlorosilane feedstocks in the polysilicon industry and gives guidance for constructing an efficient catalyst via the study of the structure and mechanism.
研究领域:
化学工程
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材料科学
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催化
·
半导体材料
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产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Qian Ping,Bingqian Zhang,Zhipeng Zhang,Kexin Lu,Yongmei Li
Iron (Fe) salt was applied extensively to remove phosphorus (P) in wastewater treatment plants (WWTPs). Exploring the formation mechanism of iron-phosphorus compounds (FePs) during the chemical P removal (CPR) process is beneficial to P recovery. In this study, the performance of P removal, FePs speciation analysis and the kinetics of P removal under different conditions (pH, Fe/P molar ratio (Fe/P mol ), type of Fe salt, dissolved organic matters) were comprehensively investigated. More than 95% of P was removed under the optimal conditions with pH = 4.7, Fe/P mol = 2, FeCl 3 or polymeric ferric sulfate (PFS) as the coagulant. The FePs formation mechanism was considerably influenced by reaction conditions. Iron-phosphate compounds were the dominant FePs species (>76%) at pH < 6.2, while more iron oxides were formed at pH ≥ 6.2 with decreased P removal efficiency. When the initial Fe/P mol was 2, iron-phosphate compound was the only product that was formed by the reaction between PO 4 3− and Fe(III) or Fe(II) ions directly. More iron oxides were generated when the initial Fe/P mol was 1 or 3. At Fe/P mol = 1, the Fe(III) was hydrolyzed to form iron oxides and trapped PO 4 3− , while at Fe/P mol = 3, iron-phosphate compounds were produced firstly and the remaining Fe(III) was hydrolyzed to form iron oxides. The pseudo-second-order kinetic model simulated the chemical P removal process well. The reaction rate of P with Fe(II) was slower than that with Fe(III), but complete removal was still achieved when the reaction time was more than 30 min. Poly-Fe salt exhibited a fast P removal rate, while the removal efficiency depended on its iron content. Organic matters in wastewater with large molecular weight and multiple functional groups (such as humic acids) inhibited P removal rate but hardly affect the removal amount. This study provides an insight into CPR by Fe salts and is beneficial for P recovery in WWTPs.
研究领域:
环境工程
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水处理
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化学工程
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产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2023
·
IF 9.8
Ligui Wu,Qiaofeng Wu,Jingcheng Xu,Lingling Rong,Xiaoli Yu,Chen Cai,Xiangfeng Huang,Xiaoming Zou
The effects of antibiotics on the proliferation of antibiotic resistant genes (ARGs) in WWTPs have drawn great attention in recent years. The effects of antibiotics on ARGs in the enhanced biological phosphorus removal (EBPR) system and its mechanisms, however, are still not well understood. In this study, EBPR systems were constructed using activated sludge to investigate the effects of ten commonly detected antibiotics in the environment on the proliferation of ARGs and the mechanisms involved. The results showed that the total abundance of ARGs increased to varying degrees with the addition of different antibiotics (0.05 mmol/L), and the top 30 ARGs increased by 271.1 % to 370.0 %. Mobile genetic elements (MGEs), functional modules, and the bacteria community were consistently related to the changes in ARGs. Refractory antibiotics, in particular, have a stronger promoting effect on transduction in the EBPR system. The insertion sequence common region (ISCR) and transposon (Tnp) were identified as crucial factors in the proliferation of ARGs. Moreover, the risk of polyphosphate accumulating organisms (PAOs) carrying ARGs in the presence of antibiotics should not be ignored. Our findings emphasize the potential efficacy of employing strategies that target the reduction of MGEs, regulation of cellular communication, and management of microbial communities to effectively mitigate the risks associated with ARGs.
研究领域:
环境工程
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微生物学
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污水处理
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遗传学
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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）