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Shi Y, Wang J, Wan H, Wan D, Wang Y, Li Y. Effective removal of nitrate in water by continuous-flow electro-dialysis ion exchange membrane bioreactor (CF-EDIMB): Performance optimization and microbial analysis. CHEMOSPHERE 2023; 341:139880. [PMID: 37619757 DOI: 10.1016/j.chemosphere.2023.139880] [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: 05/06/2023] [Revised: 07/11/2023] [Accepted: 08/17/2023] [Indexed: 08/26/2023]
Abstract
The use of nitrogen fertilizer has been causing nitrate pollution in groundwater, and there is an urgent need for efficient approach to remove nitrate from groundwater. In our job, a novel continuous-flow electrodialysis ion exchange membrane bioreactor system (CF-EDIMB) was set up to remove nitrate (NO3-) from water for the first time. Nitrate removal was positively dependent on water chamber HRT and voltage; voltage had significant effect on the water chamber effluent pH; acetate utilization efficiency was closely correlated with acetate dosage. The optimal conditions forecasted through response surface method (RSM) were given as follows: water chamber HRT was 20 h, biological chamber HRT was 24 h, voltage was 6.65 V and acetate dosage was 454.99 mg/L, dedicating to nitrate removal of 81.90% (83.70% in prediction), water chamber effluent pH of 7.10 (7.00 in prediction) and acetate utilization efficiency of 92.87% (96.51% in prediction). Meanwhile, microorganisms are crucial for nitrate removal, and the microbial community was not sensitive to the variation of acetate dosage. The microbial analysis results indicated that when CF-EDIMB system was operated for 20 d, the sulfate-reducing bacteria Sediminibacterium appeared in the biological chamber, and the effluent sulfate concentration of biological chamber was decreased. During the whole operation, Thauera was the dominant genus. Denitrifying functional genes nirS presented a better expression than the gene narG, and there was no accumulation of nitrite.
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Affiliation(s)
- Yahui Shi
- College of Environmental Engineering, Henan University of Technology, Zhengzhou, Henan, 450001, China; Zhengzhou Key Laboratory of Water Safety and Water Ecology Technology, Henan University of Technology, Zhengzhou, Henan, 450001, China.
| | - Jiekai Wang
- College of Environmental Engineering, Henan University of Technology, Zhengzhou, Henan, 450001, China; Zhengzhou Key Laboratory of Water Safety and Water Ecology Technology, Henan University of Technology, Zhengzhou, Henan, 450001, China
| | - Heyu Wan
- College of Environmental Engineering, Henan University of Technology, Zhengzhou, Henan, 450001, China; Zhengzhou Key Laboratory of Water Safety and Water Ecology Technology, Henan University of Technology, Zhengzhou, Henan, 450001, China
| | - Dongjin Wan
- College of Environmental Engineering, Henan University of Technology, Zhengzhou, Henan, 450001, China; Zhengzhou Key Laboratory of Water Safety and Water Ecology Technology, Henan University of Technology, Zhengzhou, Henan, 450001, China.
| | - Yanan Wang
- College of Environmental Engineering, Henan University of Technology, Zhengzhou, Henan, 450001, China
| | - Ying Li
- College of Environmental Engineering, Henan University of Technology, Zhengzhou, Henan, 450001, China; Zhengzhou Key Laboratory of Water Safety and Water Ecology Technology, Henan University of Technology, Zhengzhou, Henan, 450001, China
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Wang B, Hu H, Huang S, Yuan H, Wang Y, Zhao T, Gong Z, Xu X. Simultaneous nitrate and sulfate biotransformation driven by different substrates: comparison of carbon sources and metabolic pathways at different C/N ratios. RSC Adv 2023; 13:19265-19275. [PMID: 37377876 PMCID: PMC10291280 DOI: 10.1039/d3ra02749j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 06/20/2023] [Indexed: 06/29/2023] Open
Abstract
Nitrate (NO3-) and sulfate (SO42-) often coexist in organic wastewater. The effects of different substrates on NO3- and SO42- biotransformation pathways at various C/N ratios were investigated in this study. This study used an activated sludge process for simultaneous desulfurization and denitrification in an integrated sequencing batch bioreactor. The results revealed that the most complete removals of NO3- and SO42- were achieved at a C/N ratio of 5 in integrated simultaneous desulfurization and denitrification (ISDD). Reactor Rb (sodium succinate) displayed a higher SO42- removal efficiency (93.79%) with lower chemical oxygen demand (COD) consumption (85.72%) than reactor Ra (sodium acetate) on account of almost 100% removal of NO3- in both Ra and Rb. Ra produced more S2- (5.96 mg L-1) and H2S (25 mg L-1) than Rb, which regulated the biotransformation of NO3- from denitrification to dissimilatory nitrate reduction to ammonium (DNRA), whereas almost no H2S accumulated in Rb which can avoid secondary pollution. Sodium acetate-supported systems were found to favor the growth of DNRA bacteria (Desulfovibrio); although denitrifying bacteria (DNB) and sulfate-reducing bacteria (SRB) were found to co-exist in both systems, Rb has a greater keystone taxa diversity. Furthermore, the potential carbon metabolic pathways of the two carbon sources have been predicted. Both succinate and acetate could be generated in reactor Rb through the citrate cycle and the acetyl-CoA pathway. The high prevalence of four-carbon metabolism in Ra suggests that the carbon metabolism of sodium acetate is significantly improved at a C/N ratio of 5. This study has clarified the biotransformation mechanisms of NO3- and SO42- in the presence of different substrates and the potential carbon metabolism pathway, which is expected to provide new ideas for the simultaneous removal of NO3- and SO42- from different media.
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Affiliation(s)
| | - Heping Hu
- China Water Resources Pearl River Planning Surveying & Designing Co. Ltd China
| | | | | | | | | | - Zerui Gong
- South China University of Technology China
| | - Xinyue Xu
- South China University of Technology China
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Lu Y, Yan Y, Qin J, Ou L, Yang X, Liu F, Xu Y. Arbuscular mycorrhizal fungi enhance phosphate uptake and alter bacterial communities in maize rhizosphere soil. FRONTIERS IN PLANT SCIENCE 2023; 14:1206870. [PMID: 37426987 PMCID: PMC10325641 DOI: 10.3389/fpls.2023.1206870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Accepted: 05/31/2023] [Indexed: 07/11/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) can symbiose with many plants and improve nutrient uptake for their host plant. Rhizosphere microorganisms have been pointed to play important roles in helping AMF to mobilize soil insoluble nutrients, especially phosphorus. Whether the change in phosphate transport under AMF colonization will affect rhizosphere microorganisms is still unknown. Here, we evaluated the links of interactions among AMF and the rhizosphere bacterial community of maize (Zea mays L.) by using a maize mycorrhizal defective mutant. Loss of mycorrhizal symbiosis function reduced the phosphorus concentration, biomass, and shoot length of maize colonized by AMF. Using 16S rRNA gene amplicon high-throughput sequencing, we found that the mutant material shifted the bacterial community in the rhizosphere under AMF colonization. Further functional prediction based on amplicon sequencing indicated that rhizosphere bacteria involved in sulfur reduction were recruited by the AMF colonized mutant but reduced in the AMF- colonized wild type. These bacteria harbored much abundance of sulfur metabolism-related genes and negatively correlated with biomass and phosphorus concentrations of maize. Collectively, this study shows that AMF symbiosis recruited rhizosphere bacterial communities to improve soil phosphate mobilization, which may also play a potential role in regulating sulfur uptake. This study provides a theoretical basis for improving crop adaptation to nutrient deficiency through soil microbial management practices.
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Affiliation(s)
- Yufan Lu
- School of Agriculture, Yunnan University, Kunming, China
| | - Yixiu Yan
- School of Agriculture, Yunnan University, Kunming, China
| | - Jie Qin
- School of Agriculture, Yunnan University, Kunming, China
| | - Luyan Ou
- School of Agriculture, Yunnan University, Kunming, China
| | - Xinyu Yang
- School of Agriculture, Yunnan University, Kunming, China
| | - Fang Liu
- School of Agriculture, Yunnan University, Kunming, China
| | - Yunjian Xu
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Institute of Biodiversity, Yunnan University, Kunming, China
- School of Ecology and Environmental Science, Yunnan University, Kunming, Yunnan, China
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Li C, Maqbool T, Kang H, Zhang Z. In-Situ Sludge Reduction Performance and Mechanism in Sulfidogenic Anoxic-Oxic-Anoxic Membrane Bioreactors. MEMBRANES 2022; 12:865. [PMID: 36135885 PMCID: PMC9502630 DOI: 10.3390/membranes12090865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 08/31/2022] [Accepted: 09/05/2022] [Indexed: 06/16/2023]
Abstract
The excess sludge generated from the activated sludge process remains a big issue. Sustainable approaches that achieve in situ sludge reduction with satisfactory effluent quality deserve attention. This study explored the sludge reduction performance of sulfidogenic anoxic-oxic-anoxic (AOA) membrane bioreactors. The dynamics of the microbial community and metabolic pathways were further analyzed to elucidate the internal mechanism of sludge reduction. Compared with the conventional anoxic-oxic-oxic membrane bioreactor (MBRcontrol), AOAS150 (150 mg/L SO42- in the membrane tank) and AOAS300 (300 mg/L SO42- in the membrane tank) reduced biomass production by 40.39% and 47.45%, respectively. The sulfide reduced from sulfate could enhance the sludge decay rate and decrease sludge production. Extracellular polymeric substances (EPSs) destruction and aerobic lysis contributed to sludge reduction in AOA bioreactors. The relative abundance of Bacteroidetes (phylum), sulfate-reducing bacteria (SRB, genus), and Ignavibacterium (genus) increased in AOA bioreactors compared with MBRcontrol. Our metagenomic analysis indicated that the total enzyme-encoding genes involved in glycolysis, denitrification, and sulfate-reduction processes decreased over time in AOAS300 and were lower in AOAS300 than AOAS150 at the final stage of operation. The excess accumulation of sulfide in AOAS300 may inactive the functional bacteria, and sulfide inhibition induced sludge reduction.
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Affiliation(s)
- Chengyue Li
- Institute of Environmental Engineering & Nano-Technology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- Guangdong Provincial Engineering Research Centre for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Tahir Maqbool
- Institute of Environmental Engineering & Nano-Technology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- Guangdong Provincial Engineering Research Centre for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Hongyu Kang
- Institute of Environmental Engineering & Nano-Technology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- Guangdong Provincial Engineering Research Centre for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Zhenghua Zhang
- Institute of Environmental Engineering & Nano-Technology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- Guangdong Provincial Engineering Research Centre for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- School of Environment, Tsinghua University, Beijing 100084, China
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Azizan NAZ, Kamyab H, Yuzir A, Abdullah N, Vasseghian Y, Ali IH, Elboughdiri N, Sohrabi M. The selectivity of electron acceptors for the removal of caffeine, gliclazide, and prazosin in an up-flow anaerobic sludge blanket (UASB) reactor. CHEMOSPHERE 2022; 303:134828. [PMID: 35526684 DOI: 10.1016/j.chemosphere.2022.134828] [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: 03/02/2022] [Revised: 04/17/2022] [Accepted: 04/29/2022] [Indexed: 06/14/2023]
Abstract
This study attempts to investigate the relationship between the dominance of reducing conditions and the biotransformation of pharmaceutical compounds, which has been scarcely reported in a continuous anaerobic treatment process. Previous batch experiments have discovered the possible implications of different reducing conditions on the biotransformation process, but have failed to reflect actual removal performance due to substrate limitations and other operational factors. Continuously operating reactors commonly receive wastewater stream containing a wide range of electron acceptors that diversify the growth of microorganisms in anaerobic treatment. The alteration of the dominance of reducing conditions in a continuous anaerobic reactor may result in the improvement of biotransformation performance compared to a single reducing condition in a substrate-limited batch experiment. The removal of psychostimulant caffeine (CAF), anti-diabetic drug gliclazide (GCZ), and anti-hypertensive drug prazosin (PRZ) were examined through the operation of an up-flow anaerobic sludge blanket (UASB) reactor under predominant methanogenic condition (Phase I) and simultaneous reducing conditions provided by a nitrate supplement (Phase II). The results revealed high biotransformation performance for all three compounds (73-> 99%) in both Phase I and Phase II experiments and fitted the pseudo-first-order model. The biotransformation rate of CAF and PRZ were relatively lower by 25% and 29%, while the GCZ rate improvement doubled in Phase II compared to Phase I. The outcome from 16s rRNA sequencing suggested that the biotransformation of the compounds may be driven by Firmicutes and Bacteroidota in both phases, and Burkhorderiales and sulfate-reducing bacteria species in Phase II. This study proved preferential of reducing conditions does not negatively affect the biotransformation performance of each pharmaceutical compound in a continuous anaerobic reactor, but they led to varying biotransformation rate, hence shifting the microbial diversity.
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Affiliation(s)
- Nur Alyaa Zahida Azizan
- Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
| | - Hesam Kamyab
- Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia; Department of Biomaterials, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Chennai, 600 077, India.
| | - Ali Yuzir
- Department of Chemical and Environmental Engineering (ChEE), Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia.
| | - Norhayati Abdullah
- Department of Chemical and Environmental Engineering (ChEE), Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
| | - Yasser Vasseghian
- Department of Chemistry, Soongsil University, Seoul, 06978, South Korea; The University of Johannesburg, Department of Chemical Engineering, P.O. Box 17011, Doornfontein, 2088, South Africa
| | - Ismat H Ali
- Department of Chemistry, College of Science, King Khalid University, P.O. Box 9004, Abha, 61413, Saudi Arabia
| | - Noureddine Elboughdiri
- Chemical Engineering Department, College of Engineering, University of Ha'il, P.O. Box 2440, Ha'il, 81441, Saudi Arabia
| | - Mohsen Sohrabi
- Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
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Application of the EGSB-CMBR Process to High-Concentration Organic Wastewater Treatment. Processes (Basel) 2022. [DOI: 10.3390/pr10051039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
To decrease the cost of wastewater treatment at the plant, the Wuzhou Shenguan Protein Enteric Coating Production Plant designed and built an expanded granular sludge bed (EGSB)-ceramic membrane bioreactor reactor (CMBR) process for treating high-concentration organic wastewater with a capacity of 25 m3/d. The EGSB is divided into anaerobic and microaerobic sections. The purpose of the anaerobic section is to substantially degrade COD, and the main functions of the microaerobic section are to coordinate the relationship between hydrolytic acid-producing bacteria, methanogenic bacteria (MBP), and sulfate-reducing bacteria (SRB) and to mitigate the inhibitory effects between them to simultaneously remove COD and sulfate. Anaerobic ammonia-oxidizing bacteria were added to the CMBR reactor to remove both COD and ammonia nitrogen. The results of the operation showed that more than 99% of the COD was removed by the EGSB-CMBR process, while the removal rates of NH4+-N and SS were greater than 70% and 90%, respectively. In addition, the effluent met the requirements of the secondary standard of the Comprehensive Wastewater Discharge Standard (8978-1996). Economic and technical analyses showed that the modified EGSB-CMBR reactor has a high treatment efficiency, which greatly saves on the cost of the “commissioned treatment” of high-concentration organic waste liquid in the plant. Specifically, it can save more than 800,000 CNY for the plant annually.
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Zhou L, Ou P, Shao Z, Shen Y, Lu J, Zhuang WQ. Dissimilatory sulfate reduction in the cake layer of a full-scale anaerobic dynamic membrane bioreactor for hotel laundry wastewater treatment: Bacterial community and functional genes. BIORESOURCE TECHNOLOGY 2022; 351:127026. [PMID: 35314309 DOI: 10.1016/j.biortech.2022.127026] [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: 02/16/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 06/14/2023]
Abstract
Dissimilatory sulfate reduction (DSR) in cake layer of full-scale anaerobic dynamic membrane bioreactor for treating hotel laundry wastewater was studied. Change (Δ) of sulfate concentration (ΔSO42-) was positively correlated to dynamic cake layer (DCL) development, while ΔS2- was negatively correlated. ΔSO32- and ΔSorganic sulfur remained around 1.5-2.5 and 1.2-2.3 mg-S/L, respectively. Thus, DSR was the predominant sulfate reduction process in DCL. 33 binned genomes from DCL microbiome samples possessed one or more DSR functional genes. But only four binned genomes possess all functional genes, and thus can achieve complete DSR. However, no significant variations of these DSR bacteria was obseared during DCL development. Metagenomic analysis predicted that sulfate reduction in DCL was mainly carried out by collaborations between bacteria with incomplete DSR pathways. Among which, sulfite → sulfide by dissimilatory-sulfite-reductase expression bacteria was the key process. Overall results suggested that controlling dissimilatory-sulfite-reductase activities could prevent sulfide buildup in the effluent.
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Affiliation(s)
- Lijie Zhou
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China.
| | - Pingxiang Ou
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China
| | - Zhiyuan Shao
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China
| | - Yichang Shen
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China
| | - Jiahao Lu
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China
| | - Wei-Qin Zhuang
- Department of Civil and Environmental Engineering, The University of Auckland, Auckland 1142, New Zealand
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Zhu Y, Yang S, Wang W, Meng L, Guo J. Applications of Sponge Iron and Effects of Organic Carbon Source on Sulfate-Reducing Ammonium Oxidation Process. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19042283. [PMID: 35206470 PMCID: PMC8872479 DOI: 10.3390/ijerph19042283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 02/01/2022] [Accepted: 02/15/2022] [Indexed: 02/01/2023]
Abstract
The typical characteristics of wastewater produced from seafood, chemical, textile, and paper industries are that it contains ammonia, sulfate, and a certain amount of chemical oxygen demand (COD). The sulfate-reducing ammonium oxidation process is a biochemical reaction that allows both ammonia and sulfate removal, but its low growth rate and harsh reaction conditions limit its practical application. Due to the adsorption properties of the iron sponge and its robust structure, it provides a suitable living environment for microorganisms. To reduce the negative impact on the environment, we employed 4.8 kg of sponge iron in a 2.0 dm3 anaerobic sequencing batch reactor (ASBR). We investigated the effects of the type and concentration of carbon sources on the performance of the sulfate-reducing ammonium oxidation (SRAO) process. The results demonstrated that during a start-up period of 90 days, the average ammonium removal efficiency and the sulfate conversion efficiency of the reactor containing the sponge iron were 4.42% and 8.37% higher than those of the reactor without the sponge iron. The addition of the sponge iron shortens the start-up time of this greenhouse gas-free denitrification process and reduces future costs in practical applications. The removal of total nitrogen (TN) significantly increased after adding organic carbon sources and then declined sharply, while the most considerable reduction of ammonium removal efficiency from 98.4% to 30.5% was observed with adding phenol. The performance of the group employing glucose as the carbon source was recovered on the 28th day, with the average ammonium removal efficiency increasing from 49.03% to 83.5%. The results of this simulation study will help the rapid start-up of SRAO in the water treatment industry and can precisely guide the application of the SRAO process for wastewater containing different organic carbon sources.
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Characteristics and Rates of Microbial Processes in Clays of Different Mineral and Elemental Composition in Relation to Safety Prediction for ESB Clay Materials. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12041843] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Microbial activity in clay barrier materials during radioactive waste disposal can lead to a violation of important physicochemical properties of the barrier system as a whole, thereby reducing the safety of the storage facility. This work evaluates the activity of the microbial complex of five bentonite and two kaolin clays. All clay materials were found to contain microorganisms, mostly with organotrophic aerobic and anaerobic metabolism capable of forming hydrogen sulfide and transforming basic and impurity clay minerals. The activity of microorganisms can increase with the ingress of degradation products of aluminophosphate matrices and cement barriers, as well as radiolysis products. For all clay the rates of microbial processes were shown to exhibit a direct correlation with the content of organic matter, kaolinite, and potassium feldspar, and an inverse correlation with montmorillonite content. A systematic methodological approach is proposed for clay materials and their susceptibility to microbial processes. The approach makes it possible, based on the content of organic matter, biophilic elements in the samples, parameters of the respiratory activity of the microbial complex, the formation of hydrogen sulfide, and other parameters, to assess in advance the possibility of using them in barriers.
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