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Valencia‐Agami SS, Cerqueda‐García D, Gamboa‐Muñoz AM, Aguirre‐Macedo ML, García‐Maldonado JQ. Structure and composition of microbial communities in the water column from Southern Gulf of Mexico and detection of putative hydrocarbon-degrading microorganisms. ENVIRONMENTAL MICROBIOLOGY REPORTS 2024; 16:e13264. [PMID: 38692840 PMCID: PMC11062854 DOI: 10.1111/1758-2229.13264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 04/06/2024] [Indexed: 05/03/2024]
Abstract
This study assessed the bacterioplankton community and its relationship with environmental variables, including total petroleum hydrocarbon (TPH) concentration, in the Yucatan shelf area of the Southern Gulf of Mexico. Beta diversity analyses based on 16S rRNA sequences indicated variations in the bacterioplankton community structure among sampling sites. PERMANOVA indicated that these variations could be mainly related to changes in depth (5 to 180 m), dissolved oxygen concentration (2.06 to 5.93 mg L-1), and chlorophyll-a concentration (0.184 to 7.65 mg m3). Moreover, SIMPER and one-way ANOVA analyses showed that the shifts in the relative abundances of Synechococcus and Prochlorococcus were related to changes in microbial community composition and chlorophyll-a values. Despite the low TPH content measured in the studied sites (0.01 to 0.86 μL L-1), putative hydrocarbon-degrading bacteria such as Alteromonas, Acinetobacter, Balneola, Erythrobacter, Oleibacter, Roseibacillus, and the MWH-UniP1 aquatic group were detected. The relatively high copy number of the alkB gene detected in the water column by qPCR and the enrichment of hydrocarbon-degrading bacteria obtained during lab crude oil tests exhibited the potential of bacterioplankton communities from the Yucatan shelf to respond to potential hydrocarbon impacts in this important area of the Gulf Mexico.
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Affiliation(s)
- Sonia S. Valencia‐Agami
- Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de MéxicoMexico CityMexico
- Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Unidad Mérida, Departamento de Recursos del MarMeridaYucatánMexico
| | - Daniel Cerqueda‐García
- Clúster Científico y Tecnológico BioMimic®, Red de Manejo Biorracional de Plagas y VectoresInstituto de Ecología, AC–INECOLXalapaVeracruzMexico
| | - Abril M. Gamboa‐Muñoz
- Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Unidad Mérida, Departamento de Recursos del MarMeridaYucatánMexico
| | - M. Leopoldina Aguirre‐Macedo
- Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Unidad Mérida, Departamento de Recursos del MarMeridaYucatánMexico
| | - José Q. García‐Maldonado
- Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Unidad Mérida, Departamento de Recursos del MarMeridaYucatánMexico
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Fitriani N, Theresia L, O'Marga TTN, Kurniawan SB, Supriyanto A, Abdullah SRS, Rietveld LC. Performance of a modified and intermittently operated slow sand filter with two different mediums in removing turbidity, ammonia, and phosphate with varying acclimatization periods. Heliyon 2023; 9:e22577. [PMID: 38046171 PMCID: PMC10686868 DOI: 10.1016/j.heliyon.2023.e22577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 11/14/2023] [Accepted: 11/15/2023] [Indexed: 12/05/2023] Open
Abstract
The present study investigated the utilization of blood clam shells as a potential substitute for conventional media, as well as the influence of the acclimation time on the efficacy of an intermittent slow sand filter (ISSF) in the treatment of real domestic wastewater. ISSF was operated with 16 h on and 8 h off, focusing on the parameters of turbidity, ammonia, and phosphate. Two media combinations (only blood clam shells [CC] and sand + blood clam shells [SC]) were operated under two different acclimatization periods (14 and 28 d). Results showed that SC medium exhibited significantly higher removal of turbidity (p < 0.05) as compared to CC medium (45.99 ± 26.84 % vs. 3.79 ± 9.35 %), while CC exhibited slightly higher (p > 0.05) removal of ammonia (23.12 ± 20.2 % vs. 16.77 ± 16.8 %) and phosphate (18.03 ± 11.96 % vs 13.48 ± 12 %). Comparing the acclimatization periods, the 28 d of acclimatization period showed higher overall performances than the 14 d. Further optimizations need to be conducted to obtain an effluent value below the national permissible limit, since the ammonia and phosphate parameters are still slightly higher. SEM analysis confirmed the formation of biofilm on both mediums after 28 d of acclimatization; with further analysis of schmutzdecke formation need to be carried out to enrich the results.
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Affiliation(s)
- Nurina Fitriani
- Department of Biology, Faculty of Science and Technology, Universitas Airlangga, Kampus C UNAIR, Jalan Mulyorejo, Surabaya 60115, Indonesia
| | - Ledy Theresia
- Department of Biology, Faculty of Science and Technology, Universitas Airlangga, Kampus C UNAIR, Jalan Mulyorejo, Surabaya 60115, Indonesia
| | - Timothy Tjahja Nugraha O'Marga
- Department of Biology, Faculty of Science and Technology, Universitas Airlangga, Kampus C UNAIR, Jalan Mulyorejo, Surabaya 60115, Indonesia
| | - Setyo Budi Kurniawan
- Laboratory of Algal Biotechnology, Centre Algatech, Institute of Microbiology of the Czech Academy of Sciences, Opatovický mlýn, Novohradská 237, 379 81 Třeboň, Czech Republic
| | - Agus Supriyanto
- Department of Biology, Faculty of Science and Technology, Universitas Airlangga, Kampus C UNAIR, Jalan Mulyorejo, Surabaya 60115, Indonesia
| | - Siti Rozaimah Sheikh Abdullah
- Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia
| | - Luuk C. Rietveld
- Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Stevinweg 1, CN Delft 2628, Netherlands
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Progress in Deployment of Biomass-Based Activated Carbon in Point-of-Use Filters for Removal of Emerging Contaminants from Water: A Review. Chem Eng Res Des 2023. [DOI: 10.1016/j.cherd.2023.02.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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Maiyo JK, Dasika S, Jafvert CT. Slow Sand Filters for the 21st Century: A Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:1019. [PMID: 36673775 PMCID: PMC9859083 DOI: 10.3390/ijerph20021019] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/24/2022] [Accepted: 12/30/2022] [Indexed: 06/17/2023]
Abstract
Safe drinking water remains a major global challenge, especially in rural areas where, according to UNICEF, 80% of those without access to improved water systems reside. While water, sanitation, and hygiene (WASH)-related diseases and deaths are common outcomes of unsafe water, there is also an economic burden associated with unsafe water. These burdens are most prominent in rural areas in less-developed nations. Slow sand filters (SSFs), or biological sand filters (BSFs), are ideal water treatment solutions for these low-resource regions. SSFs are the oldest municipal drinking water treatment systems and improve water quality by removing suspended particles, dissolved organic chemicals, and other contaminants, effectively reducing turbidity and associated taste and odor problems. The removal of turbidity and dissolved organic compounds from the water enables the use of low-cost disinfection methods, such as chlorination. While the working principles of slow sand filtration have remained the same for over two centuries, the design, sizes, and application of slow sand filters have been customized over the years. This paper reviews these adaptations and recent reports on performance regarding contaminant removal. We specifically address the removal of turbidity and microbial contaminants, which are of great concern to rural populations in developing countries.
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Affiliation(s)
- John K. Maiyo
- Division of Environmental and Ecological Engineering, Purdue University, 500 Central Drive, West Lafayette, IN 47907, USA
| | - Sruthi Dasika
- Division of Environmental and Ecological Engineering, Purdue University, 500 Central Drive, West Lafayette, IN 47907, USA
| | - Chad T. Jafvert
- Lyles School of Civil Engineering, Division of Environmental and Ecological Engineering, Purdue University, 550 Stadium Mall Drive, West Lafayette, IN 47907, USA
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Li J, Campos LC, Zhang L, Xie W. Sand and sand-GAC filtration technologies in removing PPCPs: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 848:157680. [PMID: 35907530 DOI: 10.1016/j.scitotenv.2022.157680] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 07/24/2022] [Accepted: 07/24/2022] [Indexed: 06/15/2023]
Abstract
Concerns have been raised about the risks that pharmaceuticals and personal care products (PPCPs) in aquatic environments posed to humans and the environment. In recent years, sand filtration has been used to potentially remove these emerging contaminants from water. However, there has been no review of the effectiveness of this technology to date. This paper presents a brief introduction of sand filtration types, reviews the current progress in PPCPs removal through sand filtration, and discusses the mechanisms behind this process and the combination of granular activated carbon (GAC) and sand as an enhanced sand-GAC filtration technology. Sand filtration achieves a reasonable but highly variable degree of PPCPs removal. Biodegradation and adsorption are the two main mechanisms of PPCPs removal, in particular the biodegradation since adsorption capacity of sand is relatively low. Other processes, such as bio-sorption and indirect adsorption, may also contribute to PPCPs removal. To compensate for the inadequate PPCPs removal through sand filtration, porous GAC has been combined with sand to develop sand-GAC filtration technologies. Serial, dual, and sandwich filters have been investigated, and significant removal enhancement has been observed, due to the strengthened adsorption capacity, suggesting the applicability of these variants. Future research focus, such as investigating the influence of different operational conditions on sand filter performance, obtaining a deeper understanding of the various removal mechanisms, and investigating of long-term performance of the filter used for PPCPs removal, are suggested.
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Affiliation(s)
- Jianan Li
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Luiza C Campos
- Department of Civil, Environmental & Geomatic Engineering, Faculty of Engineering, University College London, London WC1E 6BT, UK
| | - Linyang Zhang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266520, China
| | - Wenjun Xie
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266520, China.
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Morgado ME, Hudson CL, Chattopadhyay S, Ta K, East C, Purser N, Allard S, Ferrier MD, Sapkota AR, Sharma M, Goldstein RR. The effect of a first flush rainwater harvesting and subsurface irrigation system on E. coli and pathogen concentrations in irrigation water, soil, and produce. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 843:156976. [PMID: 35768032 DOI: 10.1016/j.scitotenv.2022.156976] [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: 04/12/2022] [Revised: 06/10/2022] [Accepted: 06/21/2022] [Indexed: 06/15/2023]
Abstract
Climate change is stressing irrigation water sources, necessitating the evaluation of alternative waters such as harvested rainwater to determine if they meet water quality and food safety standards. We collected water, soil, and produce samples between June and August 2019 from two vegetable rain garden (VRG) sites in Frederick, Maryland that harvest rainwater using a first flush system, and deliver this water to produce through subsurface irrigation. The raised VRG beds include layers of gravel, sand, and soil that act as filters. We recorded the average surface soil moisture in each bed as well as antecedent precipitation. All water (n = 29), soil (n = 55), and produce (n = 57) samples were tested for generic E. coli using standard membrane filtration, and water samples were also tested for Salmonella spp. and Listeria monocytogenes by selective enrichment. No Salmonella spp. or L. monocytogenes isolates were detected in any water samples throughout the study period. Average E. coli levels from all harvested rainwater samples at both sites (1.2 and 24.4 CFU/100 mL) were well below the Good Agricultural Practices food safety guidelines. Only 7 % (3/44) of produce samples from beds irrigated with harvested rainwater were positive for E. coli. E. coli levels in soil samples were positively associated with average surface soil moisture (r2 = 0.13, p = 0.007). Additionally, E. coli presence in water samples was marginally associated with a shorter length of antecedent dry period (fewer days since preceding rainfall) (p = 0.058). Our results suggest that harvested rainwater collected through a first flush system and applied to produce through subsurface irrigation meets current food safety standards. Soil moisture monitoring could further reduce E. coli contamination risks from harvested rainwater-irrigated produce. First flush and subsurface irrigation systems could help mitigate climate change-related water challenges while protecting food safety and security.
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Affiliation(s)
- Michele E Morgado
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
| | - Claire L Hudson
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, USA; Department of Biology, Hood College, Frederick, MD, USA.
| | - Suhana Chattopadhyay
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
| | - Kaitlin Ta
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
| | - Cheryl East
- United States Department of Agriculture, Agricultural Research Service, Northeast Area, Beltsville Agricultural Research Center, Environmental Microbial and Food Safety Laboratory, Beltsville, MD, USA.
| | - Nathan Purser
- Department of Biology, Hood College, Frederick, MD, USA.
| | - Sarah Allard
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
| | - M Drew Ferrier
- Department of Biology, Hood College, Frederick, MD, USA.
| | - Amy R Sapkota
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
| | - Manan Sharma
- United States Department of Agriculture, Agricultural Research Service, Northeast Area, Beltsville Agricultural Research Center, Environmental Microbial and Food Safety Laboratory, Beltsville, MD, USA.
| | - Rachel Rosenberg Goldstein
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
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Qian S, Hou R, Yuan R, Zhou B, Chen Z, Chen H. Removal of Escherichia coli from domestic sewage using biological sand filters: Reduction effect and microbial community analysis. ENVIRONMENTAL RESEARCH 2022; 209:112908. [PMID: 35150718 DOI: 10.1016/j.envres.2022.112908] [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: 12/12/2021] [Revised: 01/28/2022] [Accepted: 02/05/2022] [Indexed: 06/14/2023]
Abstract
The recycling of sewage is an economical option to solve the water resource pressure. However, to avoid health risks to humans, pathogens in sewage must be removed before reuse. In this study, a biological sand filter (BSF) was used to remove pathogen indicator Escherichia coli (E. coli) from sewage. The biolayer (schmutzdecke layer) formation process of BSFs, operation performance, factors affecting E. coli removal and microbial community structure were evaluated. The results of schmutzdecke layer culture showed that a large number of microorganisms were attached to the upper medium of BSFs. At the same time, the BSFs could reduce both conventional contaminants and E. coli. The E. coli removal experiments revealed that the removal rate of E. coli was about 96.1% at higher effective medium depth (50 cm), the removal rate was about 95% when set hydraulic loading rate (HLR) to 0.16 m3/m2/h and the removal efficiency reached 93.6% at lower influent bacteria concentration. Finally, the microbial community analysis indicated that different BSFs had similar microbial structure, and the microbial abundance in the schmutzdecke layer was higher than that in the bottom layer in the same BSFs. Besides, Biological action played a significant role in the removal of E. coli, including the bacteriolysis of Bdellovibrio and the competition between other bacteria and E. coli. In summary, BSF was a promising technology for removing E. coli from sewage.
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Affiliation(s)
- Shengtao Qian
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083, China
| | - Rongrong Hou
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083, China
| | - Rongfang Yuan
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083, China.
| | - Beihai Zhou
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083, China
| | - Zhongbing Chen
- Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 16500, Prague, Czech Republic
| | - Huilun Chen
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083, China.
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8
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Zhao Y, Wang X, Yang J, Liu C, Wang S. A modified slow sand filtration system of epikarst spring water in karst mountainous areas, China. JOURNAL OF WATER AND HEALTH 2021; 19:229-241. [PMID: 33901020 DOI: 10.2166/wh.2021.242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Epikarst springs are commonly used for drinking water in karst mountainous areas, but they tend to bring health risks to residents because of their vulnerability. In this work, a modified slow sand filtration system (M-SSF) was established as a case study to purify and conserve the epikarst spring water. The outcomes indicate that the purification of M-SSF relies mainly on the adsorption and ion exchange of the filter medium (mixtures of heat-treated red clay and crushed limestone, MHRCCL) during the schmutzdecke juvenility, and on the schmutzdecke-formed food chain of pollutants → bacteria → protozoa after the schmutzdecke maturity. The closed water cellar lined with ceramic tiles could reduce the deterioration of epikarst spring water during storage. Via 16S rRNA sequencing, it was found that the high abundance of TM6_Dependentiae in purified epikarst spring water (PESW) suggested that the M-SSF system relies on the formation of a closed food chain to achieve effective water purification. The decrease of Pseudarcicella abundance in PESW indicated that M-SSF could effectively prevent the water quality from external influences represented by leeches. Besides, the 16S function prediction was used to qualitatively characterize microbial nitrogen metabolism, as well as organic matter degradation in water purification.
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Affiliation(s)
- Yuewen Zhao
- Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, No. 268 North Zhonghua Street, Xinhua District, Shijiazhuang 050061, China E-mail: ; Key Laboratory of Groundwater Sciences and Engineering, Ministry of Natural Resources, No. 92 East Zhongshan Road, Zhengding County, Shijiazhuang 050899, China; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, No. 388 Lumo Road, Hongshan District, Wuhan 430074, China
| | - Xiuyan Wang
- Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, No. 268 North Zhonghua Street, Xinhua District, Shijiazhuang 050061, China E-mail: ; Key Laboratory of Groundwater Sciences and Engineering, Ministry of Natural Resources, No. 92 East Zhongshan Road, Zhengding County, Shijiazhuang 050899, China
| | - Juan Yang
- Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, No. 268 North Zhonghua Street, Xinhua District, Shijiazhuang 050061, China E-mail:
| | - Changli Liu
- Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, No. 268 North Zhonghua Street, Xinhua District, Shijiazhuang 050061, China E-mail:
| | - Shuaiwei Wang
- Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, No. 268 North Zhonghua Street, Xinhua District, Shijiazhuang 050061, China E-mail: ; Key Laboratory of Groundwater Sciences and Engineering, Ministry of Natural Resources, No. 92 East Zhongshan Road, Zhengding County, Shijiazhuang 050899, China
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de Souza FH, Roecker PB, Silveira DD, Sens ML, Campos LC. Influence of slow sand filter cleaning process type on filter media biomass: backwashing versus scraping. WATER RESEARCH 2021; 189:116581. [PMID: 33186813 DOI: 10.1016/j.watres.2020.116581] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 10/27/2020] [Accepted: 10/29/2020] [Indexed: 06/11/2023]
Abstract
Biomass was assessed as a new approach for evaluating backwashed slow sand filters (BSF). Slow sand filtration (SSF) is a simple technology for water treatment, where biological mechanisms play a key role in filtration efficiency. Backwashed slow sand filters were previously recommended for small-scale filters (~1 m² of filtration area) as an alternative to conventional filters that are usually cleaned by scraping (ScSF). Biomass was never evaluated in BSF, which is a gap in the knowledge of this technology, considering the importance of its biological mechanisms. Therefore, for the first time, two filters operating under the same conditions were used to compare the influence of backwashing on biomass; one filter was cleaned by backwashing and the other by scraping. Biomass along the filter media depth (40 cm) was assessed by different techniques and compared in terms of cellular biomass (by chloroform fumigation), volatile solids, bacterial community (by 16S rRNA gene sequencing), and observations by scanning electron and fluorescence microscopy. Filters were also monitored and compared regarding filtered water quality and headloss; their differences were related to the different cleaning processes. Overall, filtered water quality was acceptable for slow sand filter standards (turbidity < 1 NTU and total coliform removal > 1 log). However, headloss developed faster on scraped filters, and biomass was different between the two filters. Backwashing did not significantly disturb biomass while scraping changed its surface sand layers. Cell biomass was more abundant and spread across the filtration depth, related to lower headloss, turbidity, and cyanobacterial breakthrough. These results agreed with the water quality and microscopy observations. The bacterial community was also less stratified in the backwashed filter media. These results expand the knowledge of backwashing use in slow sand filters, demonstrating that this process preserves more biomass than scraping. In addition, biomass preservation can lead to bacterial selectivity and faster filter ripening. Considering the importance of biomass preservation on slow sand filtration and its biological filtration mechanisms, the results presented in this paper are promising. The novel insight that BSF can preserve biomass after backwashing may contribute to increasing its application in small communities.
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Affiliation(s)
- F H de Souza
- Departamento de Engenharia Sanitária e Ambiental (ENS), Centro Tecnológico (CTC), Universidade Federal de Santa Catarina (UFSC), Campus Reitor João David Ferreira Lima, Florianópolis, Santa Catarina, Brazil, 88040-900; Department of Civil, Geomatic and Environmental Engineering (CEGE), University College London (UCL), Chadwick Building, Room GM11, Gower St, London WC1E 6BT, United Kingdom
| | - P B Roecker
- Departamento de Engenharia Sanitária e Ambiental (ENS), Centro Tecnológico (CTC), Universidade Federal de Santa Catarina (UFSC), Campus Reitor João David Ferreira Lima, Florianópolis, Santa Catarina, Brazil, 88040-900
| | - D D Silveira
- Departamento de Engenharia Sanitária e Ambiental (ENS), Centro Tecnológico (CTC), Universidade Federal de Santa Catarina (UFSC), Campus Reitor João David Ferreira Lima, Florianópolis, Santa Catarina, Brazil, 88040-900
| | - M L Sens
- Departamento de Engenharia Sanitária e Ambiental (ENS), Centro Tecnológico (CTC), Universidade Federal de Santa Catarina (UFSC), Campus Reitor João David Ferreira Lima, Florianópolis, Santa Catarina, Brazil, 88040-900
| | - L C Campos
- Department of Civil, Geomatic and Environmental Engineering (CEGE), University College London (UCL), Chadwick Building, Room GM11, Gower St, London WC1E 6BT, United Kingdom.
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Hou Q, Han D, Zhang Y, Han M, Huang G, Xiao L. The bioaccessibility and fractionation of arsenic in anoxic soils as a function of stabilization using low-cost Fe/Al-based materials: A long-term experiment. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 191:110210. [PMID: 31958624 DOI: 10.1016/j.ecoenv.2020.110210] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 01/10/2020] [Accepted: 01/12/2020] [Indexed: 06/10/2023]
Abstract
Arsenic (As)-contaminated soils occur widely worldwide. In the present study, three low-cost Fe/Al-based materials, including red soil (RS), sponge iron filter (SIF) and Al-based water treatment sludge (WTS), were applied as amendments to remediate As-contaminated soils under anoxic conditions. After 180 d of incubation, the proportion of the sum of nonspecifically absorbed As (F1) and specifically absorbed As (F2) to the total As was reduced by 6%, 52% and 13% with 5% of RS, SIF and WTS addition, respectively, compared to the control soil (31%). The results showed that among the three amendments, SIF was the most effective at decreasing As bioaccessibility in soils. Compared with RS and WTS, SIF intensified the decrease of labile fractions and the increase of unlabile fractions, and the redistribution of the amorphous oxide-bound fraction (F3) and crystalline hydrous oxide-bound fraction (F4) occurred in the SIF-amended soil. Moreover, the As stabilization processes were divided into two stages in the control and RS-amended soil, while the processes were divided into three stages in both SIF- and WTS-treated soil. The As stabilization processes in all treated soils were characterized by the transformation of labile fractions into more immobilizable fractions, except for F4 transforming into F3 in the first stage in SIF-amended soil. Correspondingly, inner-surface complexation and occlusion within Fe/Al hydroxides were the common driving mechanisms for the transformation of As fractions. Therefore, taking into consideration the results of this study, SIF could be a more promising alternative than the other two materials to passivate As in anoxic soils.
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Affiliation(s)
- Qinxuan Hou
- Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, China; Hebei and China Geological Survey Key Laboratory of Groundwater Remediation, Shijiazhuang, China
| | - Dongya Han
- School of Water Resources and Environment, Hebei GEO University, Shijiazhuang, China
| | - Ying Zhang
- Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, China
| | - Mei Han
- Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, China.
| | - Guanxing Huang
- Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, China; Hebei and China Geological Survey Key Laboratory of Groundwater Remediation, Shijiazhuang, China.
| | - Liquan Xiao
- 416 Geological Team of Hunan Bureau of Geology and Mineral Exploration and Development, Zhuzhou, China
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