Browsing by Author "Najmanová Petra"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
- ItemCombination of nanoscale-zero-valent iron and organic sub-strate stimulation for efficient remediation of co-mingled plume contaminated with Cr(VI) and chlorinated solvents(2016) Cajthaml Tomáš; Němeček Jan; Pokorný Petr; Lhotský Ondřej; Knytl Vladislav; Najmanová Petra; Steinová Jana; Černík Miroslav; Filipová Alena; Filip Jan
- ItemCombined nano-biotechnology for in-situ remediation of mixed contamination of groundwater by hexavalent chromium and chlorinated solvents(ELSEVIER SCIENCE BV, 2016) Němeček Jan; Pokorný Petr; Lhotský Ondřej; Knytl Vladislav; Najmanová Petra; Steinová Jana; Černík Miroslav; Filipová Alena; Filip Jan; Cajthaml Tomáš
- ItemThermally enhanced in situ bioremediation of groundwater contaminated with chlorinated solvents; A field test(Elsevier BV, 2018) Němeček Jan; Steinová Jana; Špánek Roman; Pluhař Tomáš; Pokorný Petr; Najmanová Petra; Knytl Vladislav; Černík MiroslavIn situ bioremediation (ISB) using reductive dechlorination is a widely accepted but relatively slow approach compared to other technologies for the treatment of groundwater contaminated by chlorinated ethenes (CVOCs). Due to the known positive kinetic effect on microbial metabolism, thermal enhancement may be a viable means of accelerating ISB. We tested thermally enhanced ISB in aquifers situated in sandy saprolite and underlying fractured granite. The system comprised pumping, heating and subsequent injection of contaminated groundwater aiming at an aquifer temperature of 20–30 °C. A fermentable substrate (whey) was injected in separate batches. The test was monitored using hydrochemical and molecular tools (qPCR and NGS). The addition of the substrate and increase in temperature resulted in a rapid increase in the abundance of reductive dechlorinators (e.g., Dehalococcoides mccartyi, Dehalobacter sp. and functional genes vcrA and bvcA) and a strong increase in CVOC degradation. On day 34, the CVOC concentrations decreased by 87% to 96% in groundwater from the wells most affected by the heating and substrate. On day 103, the CVOC concentrations were below the LOQ resulting in degradation half-lives of 5 to 6 days. Neither an increase in biomarkers nor a distinct decrease in the CVOC concentrations was observed in a deep well affected by the heating but not by the substrate. NGS analysis detected Chloroflexi dechlorinating genera (Dehalogenimonas and GIF9 and MSBL5 clades) and other genera capable of anaerobic metabolic degradation of CVOCs. Of these, bacteria of the genera Acetobacterium, Desulfomonile, Geobacter, Sulfurospirillum, Methanosarcina and Methanobacterium were stimulated by the substrate and heating. In contrast, groundwater from the deep well (affected by heating only) hosted representatives of aerobic metabolic and aerobic cometabolic CVOC degraders. The test results document that heating of the treated aquifer significantly accelerated the treatment process but only in the case of an abundant substrate.
- ItemThermally supported anaerobic bioremediation(2017) Němeček Jan; Knytl Vladislav; Najmanová Petra; Pluhař Tomáš