About 45% of the contaminated sites are dealing with heavy metal problems. An important groundwat... more About 45% of the contaminated sites are dealing with heavy metal problems. An important groundwater remediation measure is the immobilization by inducing sulfate reducing bacteria to transform the sulfates, that are very often present in the same groundwater (due to the metal mining or processing activities), into sulfides. These sulfides will precipitate the metals as insoluble metal sulfides. At the moment several studies have demonstrated the feasibility of this In Situ Bioprecipitation Process (ISBP) as well at lab scale (batch and column tests) as at field scale. However some questions arise concerning the continuation of the process, the efficiency and the sustainability of the precipitates. The presented study will try to answer these questions. The study is based on more than 12 different studies, all done by the same authors, on different groundwaters and aquifer samples. As carbon sources mostly molasses, lactate, acetate, compost, HRC and MRC are used to induce the ISBP. ...
Measurement and interpretation of mass fluxes in favor of concentrations is gaining more and more... more Measurement and interpretation of mass fluxes in favor of concentrations is gaining more and more interest, especially within the framework of the characterization and management of large-scale volatile organic carbon (VOC) groundwater contamination (source zones and plumes). Traditional methods of estimating contaminant fluxes and discharges involve individual measurements/calculations of the Darcy water flux and the contaminant concentrations. However, taken into account the spatially and temporally varying hydrologic conditions in complex, heterogeneous aquifers, higher uncertainty arises from such indirect estimation of contaminant fluxes. Therefore, the potential use of passive sampling devices for the direct measurement of groundwater-related VOC mass fluxes is examined. A review of current passive samplers for the measurement of organic contaminants in water yielded the selection of 18 samplers that were screened for a number of criteria. These criteria are related to the possible application of the sampler for the measurement of VOC mass fluxes in groundwater. This screening study indicates that direct measurement of VOC mass fluxes in groundwater is possible with very few passive samplers. Currently, the passive flux meter (PFM) is the only passive sampler which has proven to effectively measure mass fluxes in near source groundwater. A passive sampler for mass flux measurement in plume zones with regard to long-term monitoring (several months to a year) still needs to be developed or optimized. A passive sampler for long-term monitoring of contaminant mass fluxes in groundwater would be of considerable value in the development of risk-based assessment and management of soil and groundwater pollutions.
... REFERENCES 1. B. Palenik, J.-C. Block, RG Bums, WG Characklis, BE Christensen, WC Ghiorse, AG... more ... REFERENCES 1. B. Palenik, J.-C. Block, RG Bums, WG Characklis, BE Christensen, WC Ghiorse, AG Gristina, FMM Morel, WW Nichols, OH Tuovinen, G.-J. Tuschewitzki and HA Videla, WG Charaklis ... 9. L. Diels, Q. Dong, D. van der Lelie, W. Baeyens and M. Mergeay, J. Industr ...
For the removal of toxic and recalcitrant organic substances from wastewater, bioaugmentation wit... more For the removal of toxic and recalcitrant organic substances from wastewater, bioaugmentation with bacteria harbouring specific degradation pathways in activated sludge could constitute a relevant process. In this study, we examined the behaviour of a 3-chlorobenzoate (3CBA) degrading Pseudomonas putida BN210 carrying the self-transferable clc-element containing the clc-genes for 3CBA metabolism in a conventional activated sludge system (CAS) and a membrane separation bioreactor (MBR). It was shown that bioaugmentation in the MBR resulted in an increased resistance towards shock loading of 3CBA in terms of improved COD removal. Respirometry showed that the MBR sludge was less destabilized by 3CBA shock loadings than the CAS sludge. Molecular techniques including PCR-DGGE to follow strain BN210 and PCR using specific primer sets to follow the clc-element showed that strain BN210 was rapidly lost in both reactors or seems only to survive in low cell numbers. Other 3CBA degrading popul...
JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT
In June 2007, a project started in Flanders (Belgium) in which we will apply phytoremediation to ... more In June 2007, a project started in Flanders (Belgium) in which we will apply phytoremediation to clean soils that are diffusely polluted with heavy metals. Uptake ranges of heavy metals by rape seed, maize and wheat will be enhanced by increasing the bioavailability of these heavy metals by the addition of biodegradable physico‐chemical agents and by stimulating the heavy‐metal uptake capacity of the microbial community in and around the plant. In addition, the harvested biomass crops will be converted into bioenergy by using different energy‐recovery‐techniques. The energy and heavy metal mass balances will be compared for four different energy‐recovery techniques (anaerobic digestion, incineration, gasification and production of biodiesel). The overall information obtained will result in an economic evaluation of the use of phytoremediation combined with bioenergy production for the remediation of sites which are diffusely polluted with heavy metals. In the present review we will ...
International Journal of Hydrogen Energy, Jan 31, 2008
... Even though lactose in milk permeate can be converted to a variety of useful products [15] in... more ... Even though lactose in milk permeate can be converted to a variety of useful products [15] including animal feed and food additives or ... To control the pH during fermentation in each bioreactor, a pH transmitter (Stratos-E 2402, Knick) equipped with a pH electrode (InPro 3100 ...
About 45% of the contaminated sites are dealing with heavy metal problems. An important groundwat... more About 45% of the contaminated sites are dealing with heavy metal problems. An important groundwater remediation measure is the immobilization by inducing sulfate reducing bacteria to transform the sulfates, that are very often present in the same groundwater (due to the metal mining or processing activities), into sulfides. These sulfides will precipitate the metals as insoluble metal sulfides. At the moment several studies have demonstrated the feasibility of this In Situ Bioprecipitation Process (ISBP) as well at lab scale (batch and column tests) as at field scale. However some questions arise concerning the continuation of the process, the efficiency and the sustainability of the precipitates. The presented study will try to answer these questions. The study is based on more than 12 different studies, all done by the same authors, on different groundwaters and aquifer samples. As carbon sources mostly molasses, lactate, acetate, compost, HRC and MRC are used to induce the ISBP. ...
Measurement and interpretation of mass fluxes in favor of concentrations is gaining more and more... more Measurement and interpretation of mass fluxes in favor of concentrations is gaining more and more interest, especially within the framework of the characterization and management of large-scale volatile organic carbon (VOC) groundwater contamination (source zones and plumes). Traditional methods of estimating contaminant fluxes and discharges involve individual measurements/calculations of the Darcy water flux and the contaminant concentrations. However, taken into account the spatially and temporally varying hydrologic conditions in complex, heterogeneous aquifers, higher uncertainty arises from such indirect estimation of contaminant fluxes. Therefore, the potential use of passive sampling devices for the direct measurement of groundwater-related VOC mass fluxes is examined. A review of current passive samplers for the measurement of organic contaminants in water yielded the selection of 18 samplers that were screened for a number of criteria. These criteria are related to the possible application of the sampler for the measurement of VOC mass fluxes in groundwater. This screening study indicates that direct measurement of VOC mass fluxes in groundwater is possible with very few passive samplers. Currently, the passive flux meter (PFM) is the only passive sampler which has proven to effectively measure mass fluxes in near source groundwater. A passive sampler for mass flux measurement in plume zones with regard to long-term monitoring (several months to a year) still needs to be developed or optimized. A passive sampler for long-term monitoring of contaminant mass fluxes in groundwater would be of considerable value in the development of risk-based assessment and management of soil and groundwater pollutions.
... REFERENCES 1. B. Palenik, J.-C. Block, RG Bums, WG Characklis, BE Christensen, WC Ghiorse, AG... more ... REFERENCES 1. B. Palenik, J.-C. Block, RG Bums, WG Characklis, BE Christensen, WC Ghiorse, AG Gristina, FMM Morel, WW Nichols, OH Tuovinen, G.-J. Tuschewitzki and HA Videla, WG Charaklis ... 9. L. Diels, Q. Dong, D. van der Lelie, W. Baeyens and M. Mergeay, J. Industr ...
For the removal of toxic and recalcitrant organic substances from wastewater, bioaugmentation wit... more For the removal of toxic and recalcitrant organic substances from wastewater, bioaugmentation with bacteria harbouring specific degradation pathways in activated sludge could constitute a relevant process. In this study, we examined the behaviour of a 3-chlorobenzoate (3CBA) degrading Pseudomonas putida BN210 carrying the self-transferable clc-element containing the clc-genes for 3CBA metabolism in a conventional activated sludge system (CAS) and a membrane separation bioreactor (MBR). It was shown that bioaugmentation in the MBR resulted in an increased resistance towards shock loading of 3CBA in terms of improved COD removal. Respirometry showed that the MBR sludge was less destabilized by 3CBA shock loadings than the CAS sludge. Molecular techniques including PCR-DGGE to follow strain BN210 and PCR using specific primer sets to follow the clc-element showed that strain BN210 was rapidly lost in both reactors or seems only to survive in low cell numbers. Other 3CBA degrading popul...
JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT
In June 2007, a project started in Flanders (Belgium) in which we will apply phytoremediation to ... more In June 2007, a project started in Flanders (Belgium) in which we will apply phytoremediation to clean soils that are diffusely polluted with heavy metals. Uptake ranges of heavy metals by rape seed, maize and wheat will be enhanced by increasing the bioavailability of these heavy metals by the addition of biodegradable physico‐chemical agents and by stimulating the heavy‐metal uptake capacity of the microbial community in and around the plant. In addition, the harvested biomass crops will be converted into bioenergy by using different energy‐recovery‐techniques. The energy and heavy metal mass balances will be compared for four different energy‐recovery techniques (anaerobic digestion, incineration, gasification and production of biodiesel). The overall information obtained will result in an economic evaluation of the use of phytoremediation combined with bioenergy production for the remediation of sites which are diffusely polluted with heavy metals. In the present review we will ...
International Journal of Hydrogen Energy, Jan 31, 2008
... Even though lactose in milk permeate can be converted to a variety of useful products [15] in... more ... Even though lactose in milk permeate can be converted to a variety of useful products [15] including animal feed and food additives or ... To control the pH during fermentation in each bioreactor, a pH transmitter (Stratos-E 2402, Knick) equipped with a pH electrode (InPro 3100 ...
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