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Pereira Almeida FD, Bandeira de Carvalho C, Mendes Barros AR, Amancio Frutuoso FK, Bezerra Dos Santos A. Aerobic granulation and resource production under continuous and intermittent saline stress. CHEMOSPHERE 2024; 360:142402. [PMID: 38777193 DOI: 10.1016/j.chemosphere.2024.142402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 05/09/2024] [Accepted: 05/20/2024] [Indexed: 05/25/2024]
Abstract
Three sequential batch reactors (SBR) were operated to evaluate salt addition's impact on granulation, performance, and biopolymer production in aerobic granular sludge (AGS) systems. System R1 was fed without adding salt (control); system R2 operated with saline pulses, i.e., one cycle with salt (2.5 g NaCl/L) addition followed by another without salt; and R3 received continuous supplementation of 2.5 g NaCl/L. The results indicated that the reactors supplemented with salt presented higher concentrations of mixed liquor volatile suspended solids (MLVSS) and better settleability than R1, showing that osmotic pressure contributed to biomass growth, accelerated granulation, and improved physical characteristics. The faster granulation occurred in R2, thus proving the beneficial effects of intermittent salt addition through alternating pulses. Salt addition did not impair the simultaneous removal of carbon, nitrogen, and phosphorus. In fact, R2 showed better carbon removals. In conclusion, continuous or intermittent (pulsed) supplementation of 2.5 g NaCl/L did not lead to increased production of extracellular polymeric substances (EPS) and alginate-like exopolymers (ALE). This outcome could be attributed to the low saline concentration employed, a higher food-to-microorganism (F/M) ratio observed in R1, and possibly greater endogenous consumption of biopolymers in the famine period in R2 and R3 due to the greater solids retention time (SRT). Therefore, this study brings important results that contribute to a better understanding of the effect of salt in continuous dosing or in pulses as a selection pressure strategy to accelerate granulation, as well as the behavior of the AGS systems for saline effluents.
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Affiliation(s)
| | - Clara Bandeira de Carvalho
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | | | | | - André Bezerra Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil.
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2
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Zhao Y, Zhang J, Ni M, Pan Y, Li L, Ding Y. Cultivation of phosphate-accumulating biofilm: Study of the effects of acyl-homoserine lactones (AHLs) and cyclic dimeric guanosine monophosphate (c-di-GMP) on the formation of biofilm and the enhancement of phosphate metabolism capacity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 928:172408. [PMID: 38608880 DOI: 10.1016/j.scitotenv.2024.172408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 04/05/2024] [Accepted: 04/09/2024] [Indexed: 04/14/2024]
Abstract
This study investigated the mechanisms of microbial growth and metabolism during biofilm cultivation in the biofilm sequencing batch reactor (BSBR) process for phosphate (P) enrichment. The results showed that the sludge discharge was key to biofilm growth, as it terminated the competition for carbon (C) source between the nascent biofilm and the activated sludge. For the tested reactor, after the sludge discharge on 18 d, P metabolism and C source utilization improved significantly, and the biofilm grew rapidly. The P concentration of the recovery liquid reached up to 157.08 mg/L, which was sufficient for further P recovery via mineralization. Meta-omics methods were used to analyze metabolic pathways and functional genes in microbial growth during biofilm cultivation. It appeared that the sludge discharge activated the key genes of P metabolism and inhibited the key genes of C metabolism, which strengthened the polyphosphate-accumulating metabolism (PAM) as a result. The sludge discharge not only changed the types of polyphosphate-accumulating organisms (PAOs) but also promoted the growth of dominant PAOs. Before the sludge discharge, the necessary metabolic abilities that were spread among different microorganisms gradually concentrated into a small number of PAOs, and after the sludge discharge, they further concentrated into Candidatus_Contendobacter (P3) and Candidatus_Accumulibacter (P17). The messenger molecule C-di-GMP, produced mostly by P3 and P17, facilitated P enrichment by regulating cellular P and C metabolism. The glycogen-accumulating organism (GAO) Candidatus_Competibacter secreted N-Acyl homoserine lactones (AHLs), which stimulated the secretion of protein in extracellular polymeric substances (EPS), thus promoting the adhesion of microorganisms to biofilm and improving P metabolism via EPS-based P adsorption. Under the combined action of the dominant GAOs and PAOs, AHLs and C-di-GMP mediated QS to promote biofilm development and P enrichment. The research provides theoretical support for the cultivation of biofilm and its wider application.
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Affiliation(s)
- Yimeng Zhao
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Jun Zhang
- Suzhou Drainage Company Limited, Suzhou 215009, China
| | - Min Ni
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; Jiangsu Key Laboratory of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Yang Pan
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou 215009, China.
| | - Lu Li
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Yanyan Ding
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou 215009, China
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3
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Liu W, Li J, Liu T, Zheng M, Meng J, Li J. Temperature-resilient superior performances by coupling partial nitritation/anammox and iron-based denitrification with granular formation. WATER RESEARCH 2024; 254:121424. [PMID: 38460226 DOI: 10.1016/j.watres.2024.121424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Revised: 03/03/2024] [Accepted: 03/04/2024] [Indexed: 03/11/2024]
Abstract
Partial nitritation-anammox (PN/A), an energy-neutral process, is widely employed in the treatment of nitrogen-rich wastewater. However, the intrinsic nitrate accumulation limits the total nitrogen (TN) removal, and the practical application of PN/A continues to face a significant challenge at low temperatures (<15 °C). Here, an integrated partial nitritation-anammox and iron-based denitrification (PNAID) system was developed to address the concern. Two up-flow bioreactors were set up and operated for 400 days, with one as the control group and the other as the experiment group with the addition of Fe0. In comparison to the control group, the experiment group with the Fe0 supplement showed better nitrogen removal during the entire course of the experiment at different temperature levels. Specifically, the TN removal efficiency of the control group decreased from 82.9 % to 53.9 % when the temperature decreased from 30 to 12 °C, while in stark contrast, the experiment group consistently achieved 80 % of TN removal in the same condition. Apart from the enhanced nitrogen removal, the experiment group also exhibited better phosphorus removal (10.6 % versus 74.1 %) and organics removal (49.5 % versus 65.1 %). The enhanced and resilient nutrient removal performance of the proposed integrated process under low temperatures appeared to be attributed to the compact structure of granules and the increased microbial metabolism with Fe0 supplement, elucidated by a comprehensive analysis including microbial-specific activity, apparent activation energy, characteristics of granular sludge, and metagenomic sequencing. These results clearly confirmed that Fe0 supplement not only improved nitrogen removal of PN/A process, but also conferred a certain degree of robustness to the system in the face of temperature fluctuations.
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Affiliation(s)
- Wenbin Liu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Jianzheng Li
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Tao Liu
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong 999077, China
| | - Min Zheng
- Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Jia Meng
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China.
| | - Jiuling Li
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland 4072, Australia
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Zhao C, Lei J, Han F, Jiao T, Han Y, Zhou W. Novel strategy for treating high salinity oilfield produced water: Pyrite-activated peroxymonosulfate coupled with heterotrophic ammonia assimilation. WATER RESEARCH 2023; 247:120772. [PMID: 37898003 DOI: 10.1016/j.watres.2023.120772] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 10/19/2023] [Accepted: 10/20/2023] [Indexed: 10/30/2023]
Abstract
Existing conventional biological treatment techniques face numerous limitations in effectively removing total petroleum hydrocarbons (TPHs) and ammonia (NH4+-N) from oilfield-produced water (OPW), highlighting the pressing need for innovative pre-oxidation and biological treatment processes. In this study, a pyrite-activated peroxymonosulfate (PMS)-coupled heterotrophic ammonia assimilation (HAA) system was established to achieve satisfactory system performance for OPW treatment. Pyrite sustained-release Fe2+-activated PMS was used to produce SO4•- and •OH, and 71.0 % of TPHs were effectively removed from the oil wastewater. The average TPHs and NH4+-N removal efficiencies in the test group with pre-oxidation were 96.9 and 98.3 %, compared to 46.5 and 77.1 % in the control group, respectively. The maximum fluorescence intensities of tryptophan protein and aromatic protein in the test group declined by 83.7 %. Fourier transform ion cyclotron resonance mass spectrometry revealed that pre-oxidation degraded more long-chain hydrocarbons and aromatic family compound, whereas the HAA process produced more proteins and carbohydrates. Pyrite-PMS promoted the enrichment of ammonia-assimilating bacteria, alleviating the explosive increase in extracellular polymeric substances and reducing sludge settleability. The low cost, efficiency, green chemistry principles, and synergies of this approach make it a powerful solution for practical OPW treatment to reduce environmental impacts and promote sustainable wastewater treatment.
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Affiliation(s)
- Chuanfu Zhao
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of water-sediment regulation and eco-decontamination, Jinan, Shandong, PR China
| | - Jianhua Lei
- Laboratory of water-sediment regulation and eco-decontamination, Jinan, Shandong, PR China; School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong, PR China
| | - Fei Han
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of water-sediment regulation and eco-decontamination, Jinan, Shandong, PR China
| | - Tong Jiao
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of water-sediment regulation and eco-decontamination, Jinan, Shandong, PR China
| | - Yufei Han
- Laboratory of water-sediment regulation and eco-decontamination, Jinan, Shandong, PR China; School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong, PR China
| | - Weizhi Zhou
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of water-sediment regulation and eco-decontamination, Jinan, Shandong, PR China.
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Zhang M, Jiao T, Chen S, Zhou W. A review of microbial nitrogen transformations and microbiome engineering for biological nitrogen removal under salinity stress. CHEMOSPHERE 2023; 341:139949. [PMID: 37648161 DOI: 10.1016/j.chemosphere.2023.139949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 07/30/2023] [Accepted: 08/22/2023] [Indexed: 09/01/2023]
Abstract
The osmotic stress caused by salinity exerts severe inhibition on the process of biological nitrogen removal (BNR), leading to the deterioration of biosystems and the discharge of nitrogen with saline wastewater. Feasible strategies to solve the bottleneck in saline wastewater treatment have attracted great attention, but relevant studies to improve nitrogen transformations and enhance the salt-tolerance of biosystems in terms of microbiome engineering have not been systematically reviewed and discussed. This work attempted to provide a more comprehensive explanation of both BNR and microbiome engineering approaches for saline wastewater treatment. The effect of salinity on conventional BNR pathways, nitrification-denitrification and anammox, was summarized at cellular and metabolic levels, including the nitrogen metabolic pathways, the functional microorganisms, and the inhibition threshold of salinity. Promising nitrogen transformations, such as heterotrophic nitrification-aerobic denitrification, ammonium assimilation and the coupling of conventional pathways, were introduced and compared based on advantages and challenges in detail. Strategies to improve the salt tolerance of biosystems were proposed and evaluated from the perspective of microbiome engineering. Finally, prospects of future investigation and applications on halophilic microbiomes in saline wastewater treatment were discussed.
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Affiliation(s)
- Mengru Zhang
- School of Civil Engineering, Shandong University, 250061 Jinan, China; Laboratory of Water-Sediment Regulation and Eco-decontamination, 250061, Jinan, China
| | - Tong Jiao
- School of Civil Engineering, Shandong University, 250061 Jinan, China; Laboratory of Water-Sediment Regulation and Eco-decontamination, 250061, Jinan, China
| | - Shigeng Chen
- Shandong Nongda Fertilizer Sci.&Tech. Co., Ltd., Taian, Shandong, PR China
| | - Weizhi Zhou
- School of Civil Engineering, Shandong University, 250061 Jinan, China; Laboratory of Water-Sediment Regulation and Eco-decontamination, 250061, Jinan, China.
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Zhang Y, Li J, Pang Y, Shu Y, Liu S, Sang P, Sun X, Liu J, Yang Y, Chen M, Hong P. Systematic investigation of simultaneous copper biosorption and nitrogen removal from wastewater by an aerobic denitrifying bacterium of auto-aggregation. ENVIRONMENTAL RESEARCH 2023; 235:116602. [PMID: 37429397 DOI: 10.1016/j.envres.2023.116602] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 07/02/2023] [Accepted: 07/07/2023] [Indexed: 07/12/2023]
Abstract
Finding effective methods for simultaneous removal of eutrophic nutrients and heavy metals has attracted increasing concerns for the environmental remediation. Herein, a novel auto-aggregating aerobic denitrifying strain (Aeromonas veronii YL-41) was isolated with capacities for copper tolerance and biosorption. The denitrification efficiency and nitrogen removal pathway of the strain were investigated by nitrogen balance analysis and amplification of key denitrification functional genes. Moreover, the changes in the auto-aggregation properties of the strain caused by extracellular polymeric substances (EPS) production were focused on. The biosorption capacity and mechanisms of copper tolerance during denitrification were further explored by measuring changes in copper tolerance and adsorption indices, as well as by variations in extracellular functional groups. The strain showed extremely strong total nitrogen removal ability, with 67.5%, 82.08% and 78.48% of total nitrogen removal when NH4+-N, NO2--N, and NO3--N were used as the only initial nitrogen source, respectively. The successful amplification of napA, nirK, norR, and nosZ genes further demonstrated that the strain accomplished nitrate removal through a complete aerobic denitrification pathway. The production of protein-rich EPS of up to 23.31 mg/g and an auto-aggregation index of up to 76.42% may confer a strong biofilm-forming potential to the strain. Under the stress of 20 mg/L copper ions, the removal of nitrate-nitrogen was still as high as 71.4%. In addition, the strain could achieve an efficient removal of 96.9% of copper ions at an initial concentration of 80 mg/L. Scanning electron microscopy and deconvolution analysis of characteristic peaks confirmed that the strains encapsulate heavy metals by secreting EPS and, meanwhile, form strong hydrogen bonding structures to enhance intermolecular forces to resist copper ion stress. This study provides an innovative and effective biological approach for the synergistic bioaugmentation removal of eutrophic substances and heavy metals from aquatic environments.
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Affiliation(s)
- Yancheng Zhang
- College of Life Sciences, School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China
| | - Jing Li
- College of Life Sciences, School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China
| | - Yu Pang
- College of Life Sciences, School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China
| | - Yilin Shu
- College of Life Sciences, School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China
| | - Shu Liu
- College of Life Sciences, School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China
| | - Pengcheng Sang
- College of Life Sciences, School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China
| | - Xiaohui Sun
- College of Life Sciences, School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China
| | - Jiexiu Liu
- College of Life Sciences, School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China
| | - Yanfang Yang
- College of Life Sciences, School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China
| | - Minglin Chen
- College of Life Sciences, School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China.
| | - Pei Hong
- College of Life Sciences, School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China.
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7
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Han F, Zhao C, Zhang W, Jiao T, Zhang Z, Zhou W. Responses of halophilic microbial communities to changes in salt composition: Comparison between autotrophic nitrification and heterotrophic ammonia assimilation biosystems. BIORESOURCE TECHNOLOGY 2023; 386:129500. [PMID: 37468014 DOI: 10.1016/j.biortech.2023.129500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 07/13/2023] [Accepted: 07/15/2023] [Indexed: 07/21/2023]
Abstract
The concentration and proportion of chlorine (Cl-) and sulfate ions (SO42-) in actual high salinity wastewater exhibit significant fluctuations due to their diverse sources. This study compared the response of halophilic autotrophic nitrification (AN) and heterotrophic ammonia assimilation (HAA) sludges to changes in salt composition. The results demonstrated that both the AN and HAA systems maintained high ammonia removal efficiency even when exposed to mixed salt ions or pure sulfate conditions. Increasing the concentration of SO42- resulted in an increase in extracellular polymeric substances content, sludge settleability, sludge hydrophobicity, and the relative abundance of Nitrosomonas in the AN system (from 2.3% to 10.4%). The dominant heterotrophic bacteria in the HAA system underwent turnover in response to changes in salt composition conditions. The robustness and the cooperation between microorganisms of the HAA system surpassed those of the AN system. This study provides scientific foundation for treating multi-ion high salinity wastewater.
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Affiliation(s)
- Fei Han
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China; School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong, PR China
| | - Chuanfu Zhao
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China
| | - Wenchao Zhang
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China
| | - Tong Jiao
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China
| | - Zixuan Zhang
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China
| | - Weizhi Zhou
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China; School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong, PR China.
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8
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Nuid M, Aris A, Abdullah S, Fulazzaky MA, Muda K. Bioaugmentation and enhanced formation of biogranules for degradation of oil and grease: Start-up, kinetic and mass transfer studies. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 341:118032. [PMID: 37163834 DOI: 10.1016/j.jenvman.2023.118032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 04/16/2023] [Accepted: 04/25/2023] [Indexed: 05/12/2023]
Abstract
Biogranulation technology is an emerging biological process in treating various wastewater. However, the development of biogranules requires an extended period of time when treating wastewaters with high oil and grease (O&G) content. A study was therefore conducted to assess the formation of biogranules through bioaugmentation with the Serratia marcescens SA30 strain, in treating real anaerobically digested palm oil mill effluent (AD-POME), with O&G of about 4600 mg/L. The biogranules were developed in a lab-scale sequencing batch reactor (SBR) system under alternating anaerobic and aerobic conditions. The experimental data were assessed using the modified mass transfer factor (MMTF) models to understand the mechanisms of biosorption of O&G on the biogranules. The system was run with variable organic loading rates (OLR) of 0.69-9.90 kg/m3d and superficial air velocity (SAV) of 2 cm/s. After 60 days of being bioaugmented with the Serratia marcescens SA30 strain, the flocculent biomass transformed into biogranules with excellent settleability with improved treatment efficiency. The biogranules showed a compact structure and good settling ability with an average diameter of about 2 mm, a sludge volume index at 5 min (SVI5) of 43 mL/g, and a settling velocity (SV) of 81 m/h after 256 days of operation. The average removal efficiencies of O&G increased from 6 to 99.92%, respectively. The application of the MMTF model verified that the resistance to O&G biosorption is controlled via film mass transfer. This research indicates successful bioaugmentation of biogranules using the Serratia marcescens SA30 strain for enhanced biodegradation of O&G and is capable to treat real AD-POME.
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Affiliation(s)
- Maria Nuid
- Centre for Environmental Sustainability and Water Security, Research Institute for Sustainable Environment, Universiti Teknologi Malaysia, 81310, UTM Skudai, Johor Bahru, Malaysia
| | - Azmi Aris
- Centre for Environmental Sustainability and Water Security, Research Institute for Sustainable Environment, Universiti Teknologi Malaysia, 81310, UTM Skudai, Johor Bahru, Malaysia; Department of Water and Environmental Engineering, Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310, UTM Skudai, Johor Bahru, Malaysia.
| | - Shakila Abdullah
- Faculty of Applied Sciences and Technology Universiti Tun Hussein Onn Malaysia, Pagoh Education Hub, Panchor, 84600, Muar, Johor, Malaysia
| | - Mohamad Ali Fulazzaky
- School of Postgraduate Studies, Universitas Djuanda, Jalan Tol Ciawi No. 1, Ciawi, Bogor, 16700, Indonesia
| | - Khalida Muda
- Department of Water and Environmental Engineering, Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310, UTM Skudai, Johor Bahru, Malaysia
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9
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Amancio Frutuoso FK, Ferreira Dos Santos A, da Silva França LL, Mendes Barros AR, Bezerra Dos Santos A. Influence of operating regime on resource recovery in aerobic granulation systems under osmotic stress. BIORESOURCE TECHNOLOGY 2023; 376:128850. [PMID: 36898562 DOI: 10.1016/j.biortech.2023.128850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/03/2023] [Accepted: 03/06/2023] [Indexed: 06/18/2023]
Abstract
Aerobic granular sludge (AGS) systems have great potential for biopolymers recovery, especially when subjected to adverse conditions. This work aimed to study the production of alginate-like exopolymers (ALE) and tryptophan (TRY) under osmotic pressure in conventional and staggered feeding regimes. The results revealed that systems operated with conventional feed accelerated the granulation, although less resistant to saline pressures. The staggered feeding systems favored better denitrification conditions and long-term stability. Salt addition gradient increase influenced biopolymers' production. However, staggered feeding, despite decreasing the famine period, did not influence the production of resources and extracellular polymeric substances (EPS). Sludge retention time (SRT), which was not controlled, proved to be an important operational parameter with negative influences on biopolymers' production in values greater than 20 days. Thus, the principal component analysis confirmed that the production of ALE at low SRT is related to better-formed granules with good sedimentation characteristics and good AGS performances.
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Affiliation(s)
| | - Amanda Ferreira Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | | | | | - André Bezerra Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil.
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10
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Oliveira AS, Alves M, Leitão F, Tacão M, Henriques I, Castro PML, Amorim CL. Bioremediation of coastal aquaculture effluents spiked with florfenicol using microalgae-based granular sludge - a promising solution for recirculating aquaculture systems. WATER RESEARCH 2023; 233:119733. [PMID: 36801579 DOI: 10.1016/j.watres.2023.119733] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 02/04/2023] [Accepted: 02/10/2023] [Indexed: 06/18/2023]
Abstract
Aquaculture is a crucial industry in the agri-food sector, but it is linked to serious environmental problems. There is a need for efficient treatment systems that allow water recirculation to mitigate pollution and water scarcity. This work aimed to evaluate the self-granulation process of a microalgae-based consortium and its capacity to bioremediate coastal aquaculture streams that sporadically contain the antibiotic florfenicol (FF). A photo-sequencing batch reactor was inoculated with an autochthonous phototrophic microbial consortium and was fed with wastewater mimicking coastal aquaculture streams. A rapid granulation process occurred within ca. 21 days, accompanied by a substantially increase of extracellular polymeric substances in the biomass. The developed microalgae-based granules exhibited high and stable organic carbon removal (83-100%). Sporadically wastewater contained FF which was partially removed (ca. 5.5-11.4%) from the effluent. In periods of FF load, the ammonium removal slightly decreased (from 100 to ca. 70%), recovering 2 days after FF feeding ceased. A high-chemical quality effluent was obtained, complying with ammonium, nitrite, and nitrate concentrations for water recirculation within a coastal aquaculture farm, even during FF feeding periods. Members belonging to the Chloroidium genus were predominant in the reactor inoculum (ca. 99%) but were replaced from day-22 onwards by an unidentified microalga from the phylum Chlorophyta (>61%). A bacterial community proliferated in the granules after reactor inoculation, whose composition varied in response to feeding conditions. Bacteria from the Muricauda and Filomicrobium genera, Rhizobiaceae, Balneolaceae, and Parvularculaceae families, thrived upon FF feeding. This study demonstrates the robustness of microalgae-based granular systems for aquaculture effluent bioremediation, even during periods of FF loading, highlighting their potential as a feasible and compact solution in recirculation aquaculture systems.
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Affiliation(s)
- Ana S Oliveira
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, Porto 4169-005, Portugal
| | - Marta Alves
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, Porto 4169-005, Portugal
| | - Frederico Leitão
- CESAM and Biology Department, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal; Center for Functional Ecology, Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, Calçada Martim de Freitas, Coimbra 3000-456, Portugal
| | - Marta Tacão
- CESAM and Biology Department, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - Isabel Henriques
- Center for Functional Ecology, Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, Calçada Martim de Freitas, Coimbra 3000-456, Portugal
| | - Paula M L Castro
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, Porto 4169-005, Portugal
| | - Catarina L Amorim
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, Porto 4169-005, Portugal.
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11
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Zhou Y, Lian Y, Liu T, Jin X, Wang Z, Liu X, Zhou M, Jing D, Yin W, Feng J, Wang H, Zhang D. Impacts of high-quality coal mine drainage recycling for replenishment of aquatic ecosystems in arid regions of China: Bacterial community responses. ENVIRONMENTAL RESEARCH 2023; 223:115083. [PMID: 36529333 DOI: 10.1016/j.envres.2022.115083] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 12/05/2022] [Accepted: 12/14/2022] [Indexed: 06/17/2023]
Abstract
Coal mine water is usually recycled as supplementary water for aquatic ecosystems in arid and semiarid mining regions of China. To ensure ecosystem health, the coal mine water is rigorously treated using several processes, including reverse osmosis, to meet surface water quality standards. However, the potential environmental impacts of this management pattern on the ecological function of receiving water bodies are unclear. In this study, we built several microcosm water ecosystems to simulate the receiving water bodies. High-quality treated coal mine drainage was mixed into the model water bodies at different concentrations, and the sediment bacterial community response and functional changes were systematically investigated. The results showed that the high-quality coal mine drainage could still shape bacterial taxonomic diversity, community composition and structure, with a concentration threshold of approximately 50%. Moreover, both the Mantel test and the structural equation model indicated that the salinity fluctuation caused by the receiving of coal mine drainage was the primary factor shaping the bacterial communities. 10 core taxa in the molecular ecological network influenced by coal mine drainage were identified, with the most critical taxa being patescibacteria and g_Geothermobacter. Furthermore, the pathway of carbohydrate metabolism as well as signaling molecules and interactions was up-regulated, whereas amino acid metabolism showed the opposite trend. All results suggested that the complex physical-chemical and biochemical processes in water ecosystems may be affected by the coal mine drainage. The bacterial community response and underlying functional changes may accelerate internal nutrient cycling, which may have a potential impact on algal bloom outbreaks.
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Affiliation(s)
- Yaqian Zhou
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China; Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou University of Science and Technology, Suzhou, Jiangsu, 215009, PR China
| | - Ying Lian
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Tengxiang Liu
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Xian Jin
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Zhigang Wang
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Xin Liu
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Mengling Zhou
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Dan Jing
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Weiwen Yin
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Jiaying Feng
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Heli Wang
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China; Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou University of Science and Technology, Suzhou, Jiangsu, 215009, PR China.
| | - Daxin Zhang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, PR China; School of Soil & Water Conservation, Beijing Forestry University, Beijing, 100083, PR China.
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12
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Zhao C, Wang Y, Meng S, Zhang W, Zhang X, Yan L, Wei Q, Wei D. Solid slow-release carbon source assembled microbial fuel cell for promoting superior nitrogen removal in an aerobic granular sludge bioreactor. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 325:116430. [PMID: 36240640 DOI: 10.1016/j.jenvman.2022.116430] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 09/15/2022] [Accepted: 10/01/2022] [Indexed: 06/16/2023]
Abstract
Although the coupling process of microbial fuel cell (MFC) and activated sludge is widely used for organic matter removal and electric energy recovery, the problem of high effluent nitrate still exists due to the lack of influent carbon source. Herein, a poly (butanediol succinate) (PBS) assembled MFC was established in an aerobic granular sludge (AGS) bioreactor for simultaneous promoting nitrogen removal and electricity generation. Compared to AGS-Control group, the total inorganic nitrogen (TIN) and COD removal efficiencies of AGS-MFC group were improved to 84.3 ± 2.6% and 93.5 ± 0.5% after 100-days operation. The average output voltage and the maximum power density of the MFC module were 223.7 mV and 59.6 mW/m2, respectively. Through high-throughput sequencing analysis, Thauera-related denitrifying bacteria had the highest relative abundances (20.0% and 31.4%) in both bioreactors. The relative abundance of Nitrosomonas-related ammonia oxidizing bacteria (AOB) in AGS-MFC (1.8%) was enriched than AGS-Control (1.1%). In MFC module, Thauera (16.2%) with denitrification and power generation was dominant in anodic biofilms under PBS enhancement. This study provides scientific basis for the application of submersible MFC enhanced deep nitrogen removal under aerobic conditions.
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Affiliation(s)
- Chuanfu Zhao
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, PR China
| | - Yibing Wang
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, PR China
| | - Shuangyu Meng
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, PR China
| | - Wenhao Zhang
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, PR China
| | - Xinwen Zhang
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, PR China
| | - Liangguo Yan
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, PR China
| | - Qin Wei
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China
| | - Dong Wei
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, PR China.
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13
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Amancio Frutuoso FK, Ferreira Dos Santos A, da Silva França LL, Mendes Barros AR, Bezerra Dos Santos A. Influence of salt addition to stimulating biopolymers production in aerobic granular sludge systems. CHEMOSPHERE 2023; 311:137006. [PMID: 36330972 DOI: 10.1016/j.chemosphere.2022.137006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 09/27/2022] [Accepted: 10/23/2022] [Indexed: 06/16/2023]
Abstract
The influence of salt addition to stimulating biopolymers production in aerobic granular sludge (AGS) systems was evaluated. The control systems (R1: acetate and R2: propionate) initially obtained less accumulation of mixed liquor volatile suspended solids (MLVSS), indicating that the osmotic pressure in the salt-supplemented systems (R3: acetate and R4: propionate) contributed to biomass growth. However, the salt-supplemented systems collapsed between days 110 and 130 of operation. R3 and R4 showed better performance regarding nutrients removal due to the greater abundance of nitrifying and denitrifying bacteria and phosphate-accumulating organisms. Salt also contributed to the higher production of biopolymers such as alginate-like exopolymers (ALE) per gram of volatile suspended solids (VSS) (R1: 397 mgALE∙gVSS-1, R2: 140 mgALE∙gVSS-1, R3: 483 mgALE∙gVSS-1, R4: 311 mgALE∙gVSS-1). Amino acids like tyrosine and tryptophan were better identified in extracellular polymeric substances extract from salt-operated reactors. This study brings important results in the context of resource recovery by treating saline effluents.
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Affiliation(s)
| | - Amanda Ferreira Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | | | | | - André Bezerra Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil.
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14
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Han F, Li Z, Li Q, Liu Z, Han Y, Li Q, Zhou W. Cooperation of heterotrophic bacteria enables stronger resilience of halophilic assimilation biosystem than nitrification system under long-term stagnation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 848:157806. [PMID: 35932852 DOI: 10.1016/j.scitotenv.2022.157806] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 07/30/2022] [Accepted: 07/30/2022] [Indexed: 06/15/2023]
Abstract
Long-term stagnation of biosystems (with no or very little wastewater) owing to seasonal downtime or failure maintenance brings great challenges to the performance recovery after system restart. In particular, the reduction of microbial activity and change of dissolved organic matter (DOM) affect the effluent quality and subsequent treatment procedures. Monitoring the dynamics and resilience of biosystems after long-term stagnation is important to formulate targeted countermeasures for system stability. However, the influence of long-term stagnation on autotrophic nitrification (AN) and heterotrophic assimilation (HA) biosystems has not been systematically explored. Here, we used halophilic AN and HA systems to study the stability and resilience of two nitrogen removal consortia after long-term stagnation. The results showed that 97.5 % and 93 % of ammonium and 47.0 % and 90.1 % of total nitrogen were removed using the halophilic AN and HA systems, respectively, in the stable period. After four weeks of stagnation, the HA system showed stronger resilience than AN system, in terms of faster recovery of treatment performance, and less fluctuations in sludge settleability and extracellular polymeric substances. In addition, after the stagnation period, the DOM of AN system was rich in low-molecular refractory humic acid, whereas that of HA system was rich in high-molecular proteins. The stagnation period led to the replacement of the dominant heterotrophic functional microorganisms, Paracoccus and Halomonas, with Muricauda and Marinobacterium in the HA system. The microbial network results revealed that the cooperation of heterotrophic bacteria enables stronger resilience of the HA system from prolonged stagnation than the AN system. In addition, the nitrogen removal efficiency, protein to polysaccharide ratio of EPS and fluorescence intensity of DOM were significantly correlated with the microbial community composition. These results suggest that AN system has greater risks in terms of treatment performance and sludge stability than the system after long-term stagnation.
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Affiliation(s)
- Fei Han
- School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266000, China
| | - Zhe Li
- School of Civil Engineering, Shandong University, Jinan, Shandong 250002, China
| | - Qinyang Li
- School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266000, China
| | - Zhe Liu
- School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266000, China
| | - Yufei Han
- School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266000, China
| | - Qian Li
- School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266000, China
| | - Weizhi Zhou
- School of Civil Engineering, Shandong University, Jinan, Shandong 250002, China.
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15
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Lin D, Li X, Hou M, Chen Y, Zeng J, Yi X. Aerobic granular sludge cultivated from Fe-loaded activated carbon as carrier working low-strength wastewater conditions by bioreactor. CHEMOSPHERE 2022; 306:135532. [PMID: 35798157 DOI: 10.1016/j.chemosphere.2022.135532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 04/17/2022] [Accepted: 06/26/2022] [Indexed: 06/15/2023]
Abstract
This study proposes a new method to promote the granulation process while accelerating the degradation efficiency of nutrients. The new strategy could involve preparing Fe-loaded activated carbon (FAC) before start-up of granular cultivation and then cultivating the process of aerobic granular sludge (AGS) with such materials. In addition, this experiment could further comprehend how the preparation and characteristics of FAC affect the formation and properties of AGS. The conclusions showed that compared with the control, FAC enhanced the sedimentation performance and significant removal efficiency. Meanwhile, the values of protein (PN) and polysaccharide (PS) also increased significantly in the addition of FAC, indicating the production of substances were induced by FAC. Molecular biology methods indicated that the rapid production of granulation and removal of nutrients were considered as the abundance of various microbes and denitrifying bacteria at the addition of FAC. This research showed that the presence of FAC is a useful strategy for the initiation of sludge particle formation to promote the treatment of wastewater, containing COD and NH4+ at about 150-100 and 30 mg L-1.
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Affiliation(s)
- Dexin Lin
- College of Ecology and Environment, Hainan University, Haikou, Hainan, 570228, China
| | - Xinzhi Li
- College of Ecology and Environment, Hainan University, Haikou, Hainan, 570228, China
| | - Mingxiu Hou
- College of Ecology and Environment, Hainan University, Haikou, Hainan, 570228, China
| | - Yuliang Chen
- College of Ecology and Environment, Hainan University, Haikou, Hainan, 570228, China
| | - Jie Zeng
- College of Ecology and Environment, Hainan University, Haikou, Hainan, 570228, China
| | - Xuesong Yi
- College of Ecology and Environment, Hainan University, Haikou, Hainan, 570228, China.
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16
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Han F, Zhou W. Nitrogen recovery from wastewater by microbial assimilation - A review. BIORESOURCE TECHNOLOGY 2022; 363:127933. [PMID: 36100188 DOI: 10.1016/j.biortech.2022.127933] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 09/03/2022] [Accepted: 09/06/2022] [Indexed: 06/15/2023]
Abstract
The increased nitrogen (N) input with low utilization rate in artificial N management has led to massive reactive N (Nr) flows, putting the Earth in a high-risk state. It is essential to recover and recycle Nr during or after Nr removal from wastewater to reduce N input while simultaneously mitigate Nr pollution in addressing the N stress. However, mechanisms for efficient Nr recovery during or after Nr removal remain unclear. Here, the occurrence of N risk and progress in wastewater treatment in recent years as well as challenges of the current technologies for N recovery from wastewater were reviewed. Through analyzing N conversion fluxes in biogeochemical N-cycling networks, microbial N assimilation through photosynthetic and heterotrophic microorganisms was highlighted as promising alternative for synergistic N removal and recovery in wastewater treatment. In addition, the prospects and gaps of Nr recovery from wastewater through microbial assimilation are discussed.
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Affiliation(s)
- Fei Han
- School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266000, China
| | - Weizhi Zhou
- School of Civil Engineering, Shandong University, Jinan, Shandong 250002, China.
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