Browsing by Author "Lhotský Ondřej"
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- ItemAssessment of biodegradation potential at a site contaminated by a mixture of BTEX, chlorinated pollutants and pharmaceuticals using passive sampling methods; Case study(ELSEVIER SCIENCE BV, 2017) Lhotský Ondřej; Krákorová Eva; Linhartová Lucie; Křesinová Zdena; Steinová Jana; Dvořák Lukáš; Rodsand Torgeir; Filipová Alena; Kroupová Kristýna; Wimmerová Lenka; Kukačka Jan; Cajthaml TomášThe present study describes a pilot remediation test of a co-mingled plume containing BTEX, chlorinated pollutants and pharmaceuticals. Remediation was attempted using a combination of various approaches, including a pump and treat system applying an advanced oxidation process and targeted direct push injections of calcium peroxide. The remediation process was monitored intensively and extensively throughout the pilot test using various conventional and passive sampling methods, including next-generation amplicon sequencing. The results showed that the injection of oxygen-saturated treated water with residual hydrogen peroxide and elevated temperature enhanced the in situ removal of monoaromatics and chlorinated pollutants. In particular, in combination with the injection of calcium peroxide, the conditions facilitated the in situ bacterial biodegradation of the pollutants. The mean groundwater concentration of benzene decreased from 1349 μg·L− 1 prior to the test to 3 μg·L− 1 within 3 months after the calcium peroxide injections; additionally, monochlorobenzene decreased from 1545 μg·L− 1 to 36 μg·L− 1, and toluene decreased from 143 μg·L− 1 to 2 μg·L− 1. Furthermore, significant degradation of the contaminants bound to the soil matrix in less permeable zones was observed. Based on a developed 3D model, 90% of toluene and 88% of chlorobenzene bound to the soil were removed during the pilot test, and benzene was removed almost completely. On the other hand, the psychopharmaceuticals were effectively removed by the employed advanced oxidation process only from the treated water, and their concentration in groundwater remained stagnant due to inflow from the surroundings and their absence of in situ degradation. The employment of passive sampling techniques, including passive diffusion bags (PDB) for volatile organic pollutants and their respective transformation products, polar organic compound integrative samplers (POCIS) for the pharmaceuticals and in situ soil microcosms for microbial community analysis, was proven to be suitable for monitoring remediation in saturated zones.
- 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 abiotic and biotic in-situ reduction of hexavalent chromium in groundwater using nZVI and whey: A remedial pilot test(ELSEVIER SCIENCE BV, 2015) Němeček Jan; Černík Miroslav; Lacinová Lenka; Masopustová Zuzana; Lhotský Ondřej; Pokorný Petr; Cajthaml Tomáš; Filipová Alena
- 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
- ItemDosing system for remediation agents(2015) Nosek Jaroslav; Lhotský Ondřej; Němeček Jan
- ItemThe effects of hydraulic/pneumatic fracturing-enhanced remediation (FRAC-IN) at a site contaminated by chlorinated ethenes: A case study(Elsevier, 2021) Lhotský Ondřej; Kukačka Jan; Slunský Jan; Marková Kristýna; Němeček Jan; Knytl Vladislav; Cajthaml Tomáš
- ItemHydrochemical Conditions for Aerobic/Anaerobic Biodegradation of Chlorinated Ethenes&mdashA Multi-Site Assessment(MDPI, 2020) Němeček Jan; Marková Kristýna; Špánek Roman; Antoš Vojtěch; Kozubek Petr; Lhotský Ondřej; Černík Miroslav
- ItemMaterial to support biological reductive dechlorination in situ(2020) Lhotský Ondřej; Němeček Jan; Antoš Vojtěch; Marková Kristýna
- ItemNanoscale zero-valent iron application for in situ reduction of hexavalent chromium and its effects on indigenous microorganism populations(ELSEVIER SCIENCE BV, 2014) Němeček Jan; Cajthaml Tomáš; Lhotský Ondřej
- ItemPharmaceuticals, benzene, toluene and chlorobenzene removal from contaminated groundwater by combined UV/H2O2 photo-oxidation and aeration(2017) Lhotský Ondřej; Krákorová Eva; Mašín Pavel; Žebrák Radim; Linhartová Lucie; Křesinová Zdena; Kašlík Josef; Steinová Jana; Rodsand Torgeir; Filipová Alena; Petrů Klára; Kroupová Kristýna; Cajthaml TomášThis study was performed to test the feasibility of several decontamination methods for remediatingheavily contaminated groundwater in a real contaminated locality in the Czech Republic, where apharmaceuticals plant has been in operation for more than 80 years. The site is polluted mainly byrecalcitrant psychopharmaceuticals and monoaromatic hydrocarbons, such as benzene, toluene andchlorobenzene. For this purpose, an advanced oxidation technique employing UV radiation withhydrogen peroxide dosing was employed, in combination with simple aeration pretreatment. The resultsshowed that UV/H2O2was an efficient and necessary step for degradation of the pharmaceuticals;however, the monoaromatics were already removed during the aeration step. Characterization of theremoval mechanisms participating in the aeration revealed that volatilization, co-precipitation andbiodegradation contributed to the process. Thesefindings were supported by bacterial metabolite ana-lyses, phospholipid fatty acid analysis, qPCR of representatives of the degradative genes and detailedcharacterization of the formed precipitate using M€ossbauer spectroscopy and scanning electron micro-scopy. Further tests were carried out in a continuous arrangement directly connected to the wells alreadypresent in the locality. The results documented the feasibility of combination of the photo-reactoremploying UV/H2O2together with aeration pretreatment for 4 months, where the overall decontami-nation efficiency ranged from 72% to 99% of the pharmaceuticals. We recorded even better results for themonoaromatics decontamination except for one month, when we encountered some technical problemswith the aeration pump. This demonstrated the necessity of using the aeration step.
- ItemUtilisation of nanoscale zerovalent iron particles with biodegradable shell for in situ groundwater treatment via combination of nano-bio processes(2019) Lacinová Lenka; Macková Hana; Lhotský Ondřej; Heřmánková Monika