1
|
Guo X, Tang X, Zhang M, Ma X, Wang J, Liang H. New progress in the deep understanding of the biocake layer property: Combined effect of neglected protein secondary structure, morphology, and mechanism. WATER RESEARCH 2024; 250:121038. [PMID: 38157600 DOI: 10.1016/j.watres.2023.121038] [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: 09/28/2023] [Revised: 12/02/2023] [Accepted: 12/18/2023] [Indexed: 01/03/2024]
Abstract
The application of magnetic fields (MFs) and magnetic particles (MPs) in water treatment has attracted widespread attention due to their stability, strong biological compatibility, and less chemical consumption. This study introduced MPs and MFs to GDM and probed their effects on filtration performance. Predeposited large MPs (P-large) and batch-added little MPs (B-little) intervened biocake layer development, forming more open and porous structures, they also reduced biomass secretion, resulting in flux increases of 13 % in P-large and 40 % in B-little than P-little, respectively. Besides, MFs controlled MPs distribution on the biocake layer, resulting in forming of more rough and open structures. A relatively lower magnetic field of 20 mT facilitated biomass secretion, while a higher magnetic field of 50 mT decreased biomass. Furthermore, applying magnetic fields decreased the ratios of α-helix and β-sheet, and increased random coil percentage. Thus, applying magnetic field mediation would contribute to the flux improvements in I-20 and I-50 by 29 % and 32 % relative to I-0. Economic analysis suggested introducing MPs and MFs to GDM was economically feasible, synergy of MPs and MFs had more economic advantages on the community scale and MPs-assisted GDM had significant economic advantages on both community and household scales. Future works should focus on developing new technologies for the recycling of MPs and membranes. This study provided new insight into the protein secondary structures associated with GDM performance and would encourage new sustainable MFs and MPs-assisted GDM technological developments.
Collapse
Affiliation(s)
- Xishou Guo
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Xiaobin Tang
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, PR China.
| | - Meng Zhang
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Xiaobin Ma
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Jinlong Wang
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Heng Liang
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, PR China.
| |
Collapse
|
2
|
Song X, Zhang G, Luan J, Liu G, Wang J. Effect of magnetic fields on simultaneous nitrification and denitrification microbial systems. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 88:517-529. [PMID: 37578871 PMCID: wst_2023_250 DOI: 10.2166/wst.2023.250] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
Magnetic fields positively influence the nitrogen removal efficiency in activated sludge systems. However, the structural succession pattern of microorganisms by magnetic fields still remains further explored. In this paper, a magnetic simultaneous nitrification and denitrification (MSND) reactor was constructed, and the influence of optimized magnetic field intensity (0, 10, 20 and 30 mT) on the nitrogen removal efficiency was investigated at HRT 6 h, 28.0-30.0 °C, and pH 7.0-8.0. Molecular biology was used to investigate the succession process of the dominant microbial flora and the functional gene structure of MSND systems. The results showed that the denitrification effects of the MSND system were significantly enhanced, which contributed to the lower concentration of total nitrogen in the effluent of the magnetic reactor than that of the nonmagnetic group reactor. The magnetic fields induced the succession of microbial community structure and improved the stability of microbial communities, thereby the relative abundances of nitrifying and denitrifying bacteria, and the functional genes were improved. In particular, the abundance of functional genes related to gene proliferation and transmembrane transport was increased. Therefore, the efficient nitrogen removal was achieved, which gives inspiration in the enhanced wastewater treatment by magnetic fields.
Collapse
Affiliation(s)
- Xintong Song
- School of Civil Engineering and Architecture, University of Jinan, Jinan 250022, China E-mail:
| | - Guanglu Zhang
- Jinan Urban Construction Group Co., Ltd, Jinan 250014, China
| | - Jiajia Luan
- Logistics Service Office of Weifang Vocational College, Weifang 262737, China
| | - Guicai Liu
- School of Civil Engineering and Architecture, University of Jinan, Jinan 250022, China
| | - Jiabin Wang
- School of Civil Engineering and Architecture, University of Jinan, Jinan 250022, China
| |
Collapse
|
3
|
Chen J, Cui YW, Huang MQ, Yan HJ, Li D. Static magnetic field increases aerobic nitrogen removal from hypersaline wastewater in activated sludge with coexistence of fungi and bacteria. BIORESOURCE TECHNOLOGY 2023; 382:129194. [PMID: 37196737 DOI: 10.1016/j.biortech.2023.129194] [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: 03/09/2023] [Revised: 05/04/2023] [Accepted: 05/14/2023] [Indexed: 05/19/2023]
Abstract
Fungi have been found to exist in activated sludge treating saline wastewater, but their role in removing pollution has been neglected. This study explored the aerobic removal of total inorganic nitrogen (TIN) from saline wastewater under static magnetic fields (SMFs) with several strengths. Compared to the control, the aerobic removal of TIN was significantly increased by 1.47 times in 50 mT SMF, due to the increased dissimilation nitrogen removal by fungi and bacteria. Under SMF, fungal nitrogen dissimilation removal was significantly increased by 3.65 times. The fungal population size decreased, and its community composition changed significantly under SMF. In contrast, bacterial community composition and population remained relatively stable. Under SMFs, heterotrophic nitrification - aerobic denitrification bacteria Paracoccus and the fungi denitrifying Candida formed a synergistic interaction. This study elucidates the fungal role in aerobic TIN removal and provides an efficient solution to improve TIN removal from saline wastewater by SMF.
Collapse
Affiliation(s)
- Jun Chen
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China
| | - You-Wei Cui
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China.
| | - Mei-Qi Huang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China
| | - Hui-Juan Yan
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China
| | - Dong Li
- Beijing Capital Eco-Environment Protection Group Co., Ltd, Beijing 100044, China
| |
Collapse
|
4
|
Li D, Dong Y, Li S, Jiang P, Zhang J. Biological carbon promotes the recovery of anammox granular sludge after starvation. BIORESOURCE TECHNOLOGY 2023:129305. [PMID: 37311527 DOI: 10.1016/j.biortech.2023.129305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/02/2023] [Accepted: 06/07/2023] [Indexed: 06/15/2023]
Abstract
This article adopts the strategy of adding biochar and increasing HRT to accelerate the performance and particle morphology recovery of anaerobic ammonia oxidation granular sludge stored at room temperature for 68 days. The results showed that biochar accelerated the death of heterotrophic bacteria, shortened the cell lysis and lag period of the recovery process by 4 days, and it only took 28 days for the nitrogen removal performance of the reactor to recover to the original level, and 56 days for re-granulation. Biochar promoted the secretion of EPS (56.96 mg gVSS-1), and the sludge volume and nitrogen removal performance of the bioreactor remain stable. Biochar also accelerated the growth of Anammox bacteria. The abundance of Anammox bacteria in the biochar reactor reached 38.76% on the 28th day. The high abundance of functional bacteria and the optimized community structure of biochar made system (Candidatus_Kuenenia: 38.30%) more risk-resistant than control reactor.
Collapse
Affiliation(s)
- Dong Li
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100123, China.
| | - Yiwen Dong
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100123, China
| | - Shuai Li
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100123, China
| | - Pengfei Jiang
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100123, China
| | - Jie Zhang
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100123, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| |
Collapse
|
5
|
Xu J, Yuan T, Wang L, Zhang C, Lei Z, Shimizu K, Zhang Z. Enhanced fixation of dissolved inorganic carbon by algal-bacterial aerobic granular sludge during treatment of low-organic-content wastewater. BIORESOURCE TECHNOLOGY 2023; 378:128951. [PMID: 36963698 DOI: 10.1016/j.biortech.2023.128951] [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: 01/29/2023] [Revised: 03/18/2023] [Accepted: 03/20/2023] [Indexed: 06/18/2023]
Abstract
The microalgae-based wastewater treatment technologies are believed to contribute to carbon neutrality. This study investigated the inorganic carbon fixation performance in the algal-bacterial aerobic granular sludge (A-BAGS) process under cultivation at different concentrations of organic carbon (OC) and inorganic carbon (IC). The results indicated that A-BAGS in treating wastewater containing organics of 77 mg-C/L contributed little to the fixation of inorganic carbon, while the highest inorganic carbon removal efficiency of 50 % was achieved at the influent IC of 100 mg/L and OC of 7 mg/L. This high IC condition contributed to enhanced biomass growth rate and enhanced extracellular polymeric substances, while it did not affect the granular stability and nitrification efficiency. The microbial diversity was also largely enhanced. The results demonstrated the great potential of A-BAGS for simultaneous resource recovery in wastewater and inorganic carbon fixation, while operation conditions need to be further optimized.
Collapse
Affiliation(s)
- Jing Xu
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Tian Yuan
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
| | - Lanting Wang
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Chi Zhang
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhongfang Lei
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Kazuya Shimizu
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; Faculty of Life Sciences, Toyo University, 1-1-1 Izumino, Oura-gun Itakura, Gunma 374-0193, Japan
| | - Zhenya Zhang
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| |
Collapse
|
6
|
Chen R, Shuai J, Xie Y, Wang B, Hu X, Guo W, Lyu W, Zhou D, Mosa A, Wang H. Aerobic granulation and microbial community succession in sequencing batch reactors treating the low strength wastewater: The dual effects of weak magnetic field and exogenous signal molecule. CHEMOSPHERE 2022; 309:136762. [PMID: 36209862 DOI: 10.1016/j.chemosphere.2022.136762] [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: 04/16/2022] [Revised: 10/02/2022] [Accepted: 10/03/2022] [Indexed: 06/16/2023]
Abstract
The application of magneto-biological effects in wastewater treatment has been brought under the spotlight recently. This work explored the dual effects of magnetic field (MF) and exogenous N-hexanoyl-l-homoserine lactone (C6-HSL) on activated sludge granulation. Results showed that exposure to MF and C6-HSL obviously accelerated the aerobic granulation process and promoted the secretion of extracellular polymeric substances, especially polysaccharides, humic acid-like substances, aromatic proteins, and tryptophan-like substrates. Illumina MiSeq sequencing results indicated that the introduction of MF and C6-HSL can increase the diversity and richness of microbial community without antagonism, and the biological basis for rapid granulation process in this study was the enrichment of slow-growing bacteria Candidatus_Competibacter. Besides, the overgrowth of filamentous bacteria Thiothrix could be suppressed due to the presence of MF, improving the stabilities of aerobic granular sludge. This study provides a new understanding of the MF and C6-HSL effects on rapid aerobic granulation when treating the low-strength wastewater.
Collapse
Affiliation(s)
- Rongfan Chen
- School of Civil Engineering, Wuhan University, Wuhan, 430072, China
| | - Jia Shuai
- China Energy Engineering Group Guangdong Electric Power Design Institute Co., Ltd., Guangzhou, 510663, China
| | - Yijia Xie
- Central and Southern China Municipal Engineering Design & Research Institute Co., Ltd., Wuhan, 430010, China
| | - Bin Wang
- School of Civil Engineering, Wuhan University, Wuhan, 430072, China
| | - Xiaoling Hu
- School of Civil Engineering, Wuhan University, Wuhan, 430072, China
| | - Wenbin Guo
- School of Civil Engineering, Wuhan University, Wuhan, 430072, China
| | - Wanlin Lyu
- School of Civil Engineering, Wuhan University, Wuhan, 430072, China
| | - Dao Zhou
- School of Civil Engineering, Wuhan University, Wuhan, 430072, China
| | - Ahmed Mosa
- Soils Department, Faculty of Agriculture, Mansoura University, Mansoura, 35516, Egypt
| | - Hongyu Wang
- School of Civil Engineering, Wuhan University, Wuhan, 430072, China.
| |
Collapse
|
7
|
The use of the electromagnetic field in microbial process bioengineering. ADVANCES IN APPLIED MICROBIOLOGY 2022; 121:27-72. [PMID: 36328731 DOI: 10.1016/bs.aambs.2022.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
An electromagnetic field (EMF) has been shown to have various stimulatory or inhibitory effects on microorganisms. Over the years, growing interest in this topic led to numerous discoveries suggesting the potential applicability of EMF in biotechnological processes. Among these observations are stimulative effects of this physical influence resulting in intensified biomass production, modification of metabolic activity, or pigments secretion. In this review, we present the current state of the art and underline the main findings of the application of EMF in bioprocessing and their practical meaning in process engineering using examples selected from studies on bacteria, archaea, microscopic fungi and yeasts, viruses, and microalgae. All biological data are presented concerning the classification of EMF. Furthermore, we aimed to highlight missing parts of contemporary knowledge and indicate weak spots in the approaches found in the literature.
Collapse
|
8
|
Chen Y, Geng N, Hu T, Baeyens J, Wang S, Su H. Adaptive regulation of activated sludge's core functional flora based on granular internal spatial microenvironment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 319:115714. [PMID: 35839647 DOI: 10.1016/j.jenvman.2022.115714] [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: 06/05/2022] [Revised: 07/04/2022] [Accepted: 07/07/2022] [Indexed: 06/15/2023]
Abstract
A great deal of efforts has been put into studying the influence of the external macroenvironment for activated sludge to survive on microbial community succession, while granular internal spatial microenvironment should be given equal attention, because it is more directly involved in the information exchange and material transfer among microorganisms. This study systematically investigated the effects of granular microenvironment on spatial colonization and composition of sludge's core functional flora, and the corresponding difference of biological treatment performance. High content of extracellular-proteins (67.53 mg/gVSS) or extracellular-polysaccharide (65.02 mg/gVSS) stimulated the microbial flocculation and aggregation of 0.5-1.5 mm granules (GS) or 1.5-3.0 mm granules (GM), respectively, which was resulted from excellent cell hydrophobicity (59.26%) or viscosity (3.47 mPa s), therefore, constituted relatively dense porous frame. More hollow space existed in 3.0-5.0 mm granules (GL), which formed loose skeleton with 0.213 mL/g of total pore volume and 17.21 nm of average pore size. Combining scanning electron microscope images and fluorescent in-situ hybridization based microbiological analysis, aerobic nitrifiers were observed to wrap or surround anaerobic bacteria, or facultative/anaerobic bacteria were self-encapsulated, which created granule's unique microenvironment with alternating aerobic and anaerobic zones. GS has the most rich organic matter degrading bacteria and anaerobic heterotrophic denitrifiers, while GM and GL presented the greatest relative abundance of facultative and aerobic denitrifiers, respectively. The activity of dehydrogenase and nitrogen invertase of GM showed be 1.32-3.09 times higher than those of GS and GL, contributing to its higher carbon and nitrogen removal. These findings highlight the importance of granular microenvironment to adaptive regulation of activated sludge's core functional flora and corresponding pollutant removal performance.
Collapse
Affiliation(s)
- Yingyun Chen
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Nanfei Geng
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Tenghui Hu
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Jan Baeyens
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Shaojie Wang
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China.
| | - Haijia Su
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China.
| |
Collapse
|
9
|
Song T, Zhang X, Li J. The formation and distinct characteristics of aerobic granular sludge with filamentous bacteria in low strength wastewater. BIORESOURCE TECHNOLOGY 2022; 360:127409. [PMID: 35667533 DOI: 10.1016/j.biortech.2022.127409] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/27/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
In low strength wastewater, aerobic granular sludge (AGS) with filamentous bacteria is often found and regarded as unstable AGS. However, in this study, a new view is proposed that AGS with filamentous bacteria (FAGS) may be the result of low strength wastewater selection. FAGS was found when AGS was cultivated for 30 days. By increasing the settling time, FAGS could keep the mixed liquid suspension (MLSS) at 0.89 g/L. FAGS showed excellent ammonia nitrogen removal performance. The ammonia nitrogen oxidation rate and denitrification rate of FAGS were 1.72 and 1.20 times higher than that of AGS, respectively. FAGS have large specific surface area (15.99 m2/g), high extracellular polymeric substances (EPS) content (>200 mg/gVSS), and strong stability (integrity coefficient: 2 ∼ 8%). Furthermore, FAGS showed higher potential than AGS in many aspects such as carbon metabolism, nitrogen metabolism, and toxicant degradation.
Collapse
Affiliation(s)
- Tao Song
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, Shenzhen, Guangdong 518055, PR China
| | - Xiaolei Zhang
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, Shenzhen, Guangdong 518055, PR China
| | - Ji Li
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, Shenzhen, Guangdong 518055, PR China; Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, Shenzhen 518055, PR China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| |
Collapse
|
10
|
Wang H, Guo L, Ren X, Gao M, Jin C, Zhao Y, Ji J, She Z. Enhanced aerobic granular sludge by static magnetic field to treat saline wastewater via simultaneous partial nitrification and denitrification (SPND) process. BIORESOURCE TECHNOLOGY 2022; 350:126891. [PMID: 35217165 DOI: 10.1016/j.biortech.2022.126891] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/16/2022] [Accepted: 02/18/2022] [Indexed: 05/12/2023]
Abstract
Saline wastewater poses a threat to biological nitrogen removal. This study investigated whether and how static magnetic field (SMF) can improve the salt-tolerance of aerobic granular sludge (AGS) in two simultaneous partial nitrification and denitrification (SPND) reactors. Results confirmed that the SMF improved the mean size and settleability of granules, stimulated secretion of extracellular polymeric substances with high protein content, in turn enhancing the aerobic granulation. Although high salt stress inhibited functional microorganisms, the SMF maintained better SPND performance with average COD removal, TN removal and nitrite accumulation ratio finally recovering to 100%, 72.9% and 91.1% respectively. High throughput sequencing revealed that functional bacteria evolved from Paracoccus to halotolerant genera Xanthomarina, Thauera, Pseudofulvimonas and Azoarcus with stepwise increasing salinity. The enhanced salt-tolerance may be because the SMF promoted the activity of these halotolerant bacteria. Therefore, this study proposes an economic, effective and environmental biotechnology for saline wastewater treatment.
Collapse
Affiliation(s)
- Hutao Wang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Liang Guo
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; Key Laboratory of Marine Environmental and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
| | - Xiaomin Ren
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Mengchun Gao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Chunji Jin
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Yangguo Zhao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Junyuan Ji
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Zonglian She
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| |
Collapse
|