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Cohen M, Weisbrod N. Field Scale Mobility and Transport Manipulation of Carbon-Supported Nanoscale Zerovalent Iron in Fractured Media. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:7849-7858. [PMID: 29900735 DOI: 10.1021/acs.est.8b01226] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In field applications, mostly in porous media, transport of stabilized nano zerovalent iron particles (nZVI) has never exceeded a few meters in range. In the present study, the transport of Carbo-Iron Colloids (CIC), a composite material of activated carbon as a carrier for nZVI stabilized by carboxymethyl cellulose (CMC), was tested under field conditions. The field site lies within a fractured chalk aquitard characterized by moderately saline (∼13 mS) groundwater. A forced gradient tracer test was conducted where one borehole was pumped at a rate of 8 L/min and CMC-stabilized CIC was introduced at an injection borehole 47 m up-gradient. Two CIC-CMC field applications were conducted: one used high 100% wt CMC (40 g/L) and a second used lower 9% wt loading (∼2.7 g/L). Iodide was injected as a conservative tracer with the CIC-CMC in both cases. The ratio between the CIC-CMC and iodide recovery was 76% and 45% in the high and low CMC loading experiments, respectively. During the low CMC loading experiment, the pumping rate was increased, leading to an additional CIC recovery of 2.5%. The results demonstrate the potentially high mobility of nZVI in fractured environments and the possibility for transport manipulation through the adjustment of stabilizer concentration and transport velocity.
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Affiliation(s)
- Meirav Cohen
- The Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research , Ben Gurion University of the Negev , Sde Boker Campus , 84990 Israel
| | - Noam Weisbrod
- The Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research , Ben Gurion University of the Negev , Sde Boker Campus , 84990 Israel
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Valsala R, Govindarajan SK. Mathematical Modeling on Mobility and Spreading of BTEX in a Discretely Fractured Aquifer System Under the Coupled Effect of Dissolution, Sorption, and Biodegradation. Transp Porous Media 2018. [DOI: 10.1007/s11242-018-1049-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Balaban N, Bernstein A, Gelman F, Ronen Z. Microbial degradation of the brominated flame retardant TBNPA by groundwater bacteria: laboratory and field study. CHEMOSPHERE 2016; 156:367-373. [PMID: 27183339 DOI: 10.1016/j.chemosphere.2016.04.127] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 04/10/2016] [Accepted: 04/30/2016] [Indexed: 06/05/2023]
Abstract
In the present study, the biodegradation of the brominated flame retardant tribromoneopentylalcohol (TBNPA) by a groundwater enrichment culture was investigated using a dual carbon ((13)C/(12)C)- bromine ((81)Br/(79)Br) stable isotope analysis. An indigenous aerobic bacterial consortium was enriched from the polluted groundwater underlying an industrial site in the northern Negev Desert, Israel, where TBNPA is an abundant pollutant. Aerobic biodegradation was shown to be rapid, with complete debromination within a few days, whereas anaerobic biodegradation was not observed. Biodegradation under aerobic conditions was accompanied by a significant carbon isotope effect with an isotopic enrichment factor of ɛCbulk = -8.8‰ ± 1.5‰, without any detectable bromine isotope fractionation. It was found that molecular oxygen is necessary for biodegradation to occur, suggesting an initial oxidative step. Based on these results, it was proposed that H abstraction from the C-H bond is the first step of TBNPA biodegradation under aerobic conditions, and that the C-H bond cleavage results in the formation of unstable intermediates, which are rapidly debrominated. A preliminary isotopic analysis of TBNPA in the groundwater underlying the industrial area revealed that there are no changes in the carbon and bromine isotope ratio values downstream of the contamination source. Considering that anoxic conditions prevail in the groundwater of the contaminated site, the lack of isotope shifts in TBNPA indicates the lack of TBNPA biodegradation in the groundwater, in accordance with our findings.
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Affiliation(s)
- Noa Balaban
- Department of Environmental Hydrology & Microbiology (EHM), The Zuckerberg Institute for Water Research (ZIWR), The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel.
| | - Anat Bernstein
- Department of Environmental Hydrology & Microbiology (EHM), The Zuckerberg Institute for Water Research (ZIWR), The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel.
| | - Faina Gelman
- Geological Survey of Israel, 30 Malkhei Israel St., Jerusalem 95501, Israel.
| | - Zeev Ronen
- Department of Environmental Hydrology & Microbiology (EHM), The Zuckerberg Institute for Water Research (ZIWR), The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel.
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Kanmani S, Gandhimathi R, Muthukkumaran K. Bioclogging in porous media: influence in reduction of hydraulic conductivity and organic contaminants during synthetic leachate permeation. JOURNAL OF ENVIRONMENTAL HEALTH SCIENCE & ENGINEERING 2014; 12:126. [PMID: 25400936 PMCID: PMC4229613 DOI: 10.1186/s40201-014-0126-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 10/14/2014] [Indexed: 06/04/2023]
Abstract
In this study the concept of biofilm accumulation in the sand column was promoted to assess the changes in hydraulic conductivity and concentration of organic contaminants of the synthetic leachate. Four different combinations of column study were carried out using synthetic leachate as a substrate solution. Mixed and stratified mode of experiments with two different sizes (0.3 mm and 0.6 mm) of sand grains were used for column filling. Two columns were acting as a blank, the remaining two columns amended with mixed microbial cultures which were isolated from leachate. The column was operated with continuous synthetic leachate supply for 45 days. The results indicated that the highest hydraulic conductivity reduction occurred in the mixed sand microbial column with 98.8% when compared to stratified sand microbial column. The analysis of organic contaminants of the effluent leachate was also clearly shown that the mixed sand amended with microbes poses a suitable remedial measure when compared to natural and synthetic liners for controlling the leachate migration in the subsurface environment.
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Affiliation(s)
- Subramaniam Kanmani
- Department of Civil Engineering, National Institute of Technology, Tiruchirappalli, Tamilnadu, India
| | - Rajan Gandhimathi
- Department of Civil Engineering, National Institute of Technology, Tiruchirappalli, Tamilnadu, India
| | - Kasinathan Muthukkumaran
- Department of Civil Engineering, National Institute of Technology, Tiruchirappalli, Tamilnadu, India
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The Effect of Microbial Activity on Biodegradation of 2,4,6-Tribromophenol and Flow in Naturally Fractured Chalk Cores. ACTA ACUST UNITED AC 2013. [DOI: 10.1029/162gm18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Bozorg A, Sen A, Gates ID. A new approach to model the spatiotemporal development of biofilm phase in porous media. Environ Microbiol 2011; 13:3010-23. [DOI: 10.1111/j.1462-2920.2011.02578.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Chrysikopoulos CV, Masciopinto C, La Mantia R, Manariotis ID. Removal of biocolloids suspended in reclaimed wastewater by injection into a fractured aquifer model. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:971-7. [PMID: 20041663 DOI: 10.1021/es902754n] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Two pilot-scale fractured aquifer models (FAMs) consisting of horizontal limestone slabs were employed to investigate the removal of biocolloids suspended in reclaimed wastewater. To better understand the behavior of real fractured aquifers, these FAMs intentionally were not "clean". The fracture apertures were randomly spread with soil deposits, and both FAMs were preflooded with reclaimed wastewater to simulate the field conditions of the Nardo fractured aquifer in the Salento area, Italy, where fractures are not clean due to artificial groundwater recharge. One of the FAMs was injected with secondary effluent from a wastewater treatment plant collected prior to the chlorination step and the other with exactly the same effluent, which was further treated in a commercial membrane reactor. Consequently, the organic and pathogen concentrations were considerably higher in the secondary effluent than in the membrane reactor effluent. Injected wastewater was continuously recirculated. Pathogen removal was greater for the secondary wastewater than the cleaner membrane reactor effluent. A simple mathematical model was developed to describe fracture clogging. The results suggest that the hydraulic conductivity of FAMs can be significantly degraded due to retention of viable and inactivated biocolloids suspended in reclaimed wastewater.
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Tang XY, Weisbrod N. Colloid-facilitated transport of lead in natural discrete fractures. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2009; 157:2266-2274. [PMID: 19395135 DOI: 10.1016/j.envpol.2009.03.034] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2008] [Revised: 03/24/2009] [Accepted: 03/27/2009] [Indexed: 05/27/2023]
Abstract
Colloid-facilitated transport of lead (Pb) was explored in a natural chalk fracture with an average equivalent hydraulic aperture of 139 microm. Tracer solution was prepared by adding montmorillonite (100 mg L(-1)) and/or humic acid (HA) (10 mg L(-1)) to modified artificial rainwater containing dissolved Pb (21.4 mg Pb L(-1)), naturally precipitated PbCO(3) particles (16.4 mg Pb L(-1)) and LiBr (39.0 mg L(-1)). We found that Pb is only mobile when associated with colloids. PbCO(3) particles were not mobile in the fracture. The addition of HA to the montmorillonite suspension increased the suspension's mobility and therefore promoted the colloid-facilitated transport of Pb. The increases in pH and sodium absorption ratio induced by the chalk-tracer solution interactions appeared to increase the dispersion and mobilization of colloids entering the fracture. The dominant colloid-facilitated transport of Pb reported in this study has significant implications for risk assessment of Pb mobility in fractured rocks.
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Affiliation(s)
- Xiang-Yu Tang
- Department of Environmental Hydrology & Microbiology, Zuckerberg Institute for Water Research, J. Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, P.O. Box 192, Midreshet Ben-Gurion 84990, Israel
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Seifert D, Engesgaard P. Use of tracer tests to investigate changes in flow and transport properties due to bioclogging of porous media. JOURNAL OF CONTAMINANT HYDROLOGY 2007; 93:58-71. [PMID: 17336422 DOI: 10.1016/j.jconhyd.2007.01.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Revised: 01/09/2007] [Accepted: 01/19/2007] [Indexed: 05/14/2023]
Abstract
Tracer tests were conducted in three laboratory columns to study changes in the hydraulic properties of a porous medium due to bioclogging. About 30 breakthrough curves (BTCs) for each column were obtained. The BTCs were analyzed using analytical equilibrium and dual-porosity models, and estimates of the hydrodynamic dispersion and mass transfer coefficients were obtained by curve fitting. The change in transport properties developed in three stages: an initial phase (I) with no significant changes in transport properties, phase II with growth of biomass near the inlet of the columns causing changes in dispersivity, and phase III with added growth of micro-colonies deeper in the columns causing mass transfer of solutes from the water phase to the biophase. Tracer transport changed from being uniform to more non-uniform with increase in mass transfer of the tracer between the mobile phase and the immobile biomass. An increase in the bulk dispersivity value of up to one order of magnitude was observed. Numerical simulations suggest that local dispersivity values may be as much as 40 times higher in the more severe clogged areas inside the column. The bulk hydraulic conductivities of the columns decreased by up to three orders of magnitude. The hydraulic conductivity and dispersivity parameters were almost recovered after disinfection of the columns. Different models relating the changes of the hydraulic conductivity to the changes in the mobile porosity due to bioclogging were reviewed, and the micro-colony relation of Thullner et al. [Thullner, M., Zeyer, J., Kinzelbach, W., 2002. Influence of microbial growth on hydraulic properties of pore networks, Transport in Porous Media, 49, 99-122.] was found to best describe the relation between the bulk hydraulic parameters.
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Affiliation(s)
- Dorte Seifert
- Institute of Environment and Resources, Technical University of Denmark, Kongens Lyngby, Denmark
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Antizar-Ladislao B, Galil NI. Biodegradation of 2,4,6-trichlorophenol and associated hydraulic conductivity reduction in sand-bed columns. CHEMOSPHERE 2006; 64:339-49. [PMID: 16469360 DOI: 10.1016/j.chemosphere.2005.12.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2005] [Revised: 12/18/2005] [Accepted: 12/20/2005] [Indexed: 05/06/2023]
Abstract
The aim of this research was to investigate the long-term hydraulic conductivity changes in sand-bed columns exposed to 2,4,6-trichlorophenol (TCP). Continuous flow laboratory studies were conducted using sand-bed columns (15 cm i.d.; 200 cm length) at 20+/-1 degrees C during 365 d. The influence of (i) initial loads of 2,4,6-TCP (15, 30, 45 and 60 mg kg(-1) of 2,4,6-TCP), and (ii) recirculating water velocity (0.09, 0.56 and 1.18 cm min(-1)) on the biodegradation of 2,4,6-TCP and hydraulic conductivity changes in the sand-bed columns were investigated. The experimental results indicated that biodegradation of 2,4,6-TCP followed pseudo-first-order kinetics in the range of k(1)=0.01-1.64 d(-1), and it was influenced by initial load (p<0.01) and recirculating water velocity (p<0.01). Indigenous microbial biomass growth and changes resulted in a spatial (180 cm) and temporal (365 d) reduction of hydraulic conductivity in the sand-bed columns by up to two orders of magnitude during biodegradation of 2,4,6-TCP. The fastest hydraulic conductivity reductions were observed in the sand-bed column operated at the highest recirculating water velocity and highest cumulative load of 2,4,6-TCP following 365 d of continuous treatment (p<0.05).
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Arnon S, Ronen Z, Adar E, Yakirevich A, Nativ R. Two-dimensional distribution of microbial activity and flow patterns within naturally fractured chalk. JOURNAL OF CONTAMINANT HYDROLOGY 2005; 79:165-86. [PMID: 16099071 DOI: 10.1016/j.jconhyd.2005.06.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2004] [Revised: 06/16/2005] [Accepted: 06/17/2005] [Indexed: 05/04/2023]
Abstract
The two-dimensional distribution of flow patterns and their dynamic change due to microbial activity were investigated in naturally fractured chalk cores. Long-term biodegradation experiments were conducted in two cores ( approximately 20 cm diameter, 31 and 44 cm long), intersected by a natural fracture. 2,4,6-tribromophenol (TBP) was used as a model contaminant and as the sole carbon source for aerobic microbial activity. The transmissivity of the fractures was continuously reduced due to biomass accumulation in the fracture concurrent with TBP biodegradation. From multi-tracer experiments conducted prior to and following the microbial activity, it was found that biomass accumulation causes redistribution of the preferential flow channels. Zones of slow flow near the fracture inlet were clogged, thus further diverting the flow through zones of fast flow, which were also partially clogged. Quantitative evaluation of biodegradation and bacterial counts supported the results of the multi-tracer tests, indicating that most of the bacterial activity occurs close to the inlet. The changing flow patterns, which control the nutrient supply, resulted in variations in the concentrations of the chemical constituents (TBP, bromide and oxygen), used as indicators of biodegradation.
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Affiliation(s)
- Shai Arnon
- Department of Environmental Hydrology and Microbiology, Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus 84990, Israel.
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