Anaerobic bioventing of unsaturated zone contaminated with DDT and DNT

2001 ◽  
Vol 43 (2) ◽  
pp. 35-42 ◽  
Author(s):  
J. K. Shah ◽  
G. D. Sayles ◽  
M. T. Suidan ◽  
P. Mihopoulos ◽  
S. Kaskassian
Keyword(s):  
Electron Donor ◽  
Vadose Zone ◽  
Unsaturated Zone ◽  
Degradation Products ◽  
Gas Mixture ◽  
Anaerobic Conditions ◽  
Soil Columns ◽  
Waste Streams ◽  
Anaerobic Microorganisms ◽  
Anaerobic Environment

Initial degradation of highly chlorinated compounds and nitroaromatic compounds found in munition waste streams is accelerated under anaerobic conditions followed by aerobic treatment of the degradation products. The establishment of anaerobic environment in a vadose zone can be accomplished by feeding appropriate anaerobic gas mixture, i.e., “anaerobic bioventing”. The gas mixture contains an electron donor for the reduction of these compounds. Lab scale study was conducted to evaluate potential of anaerobic bioventing for the treatment of an unsaturated zone contaminated with 1,1,1-trichloro -2,2-bis(p-chlorophenyl)ethane (DDT) and 2,4-dinitrotoluene (DNT). Hydrogen was used as the electron donor. Using the soil columns innoculate with anaerobic microorganisms, it was observed that by feeding a gas mixture of 1% hydrogen, 1% carbon dioxide and nitrogen, methanogenic conditions were established and DDT was reductively dechlorinated. 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD) accumulated as the intermediate product. The half life of DDT was calculated to be 8.5 months. DNT completely disappeared after six months of operation and no intermediates could be detected.

Improved chamber for the isolation of anaerobic microorganisms

1976 ◽  
Vol 4 (1) ◽  
pp. 40-45
Author(s):  
M E Cox ◽  
J I Mangels
Keyword(s):  
Anaerobic Bacteria ◽  
Gas Mixture ◽  
Anaerobic Conditions ◽  
Co2 Gas ◽  
Anaerobic Microorganisms ◽  
The Media ◽  
To Receive ◽  
Latex Rubber

A small portable chamber for the recovery of anaerobic bacteria is described. This rigid chamber is constructed of clear acrylic with dimensions of 30 inches (ca. 76.2 cm) wide, 18 inches (ca. 44.7 cm) deep, and 18 inches (ca. 44.7 cm) high. Conventional bacteriological techniques can be used inside the chamber to efficiently isolate strict anaerobic organisms. An adapter allows the attachment of a standard anaerobic jar to the outside of the chamber. The jar can be used to store reduced media. Once the jar is attached to the chamber and the media is removed to the interior of the chamber, the jar is available to receive inoculated media. The anaerobic jar can then be removed from the chamber, without contaminating the jar or chamber with oxygen, and be placed in a conventional 37degreesC incubator. This chamber also allows the microbiologist to process cultures without wearing gloves as was necessary with previous anaerobic chambers. Air-tight latex rubber sleeves seal around the microbiologists arms and to the armport flange of the chamber to prevent the introduction of oxygen into the chamber. Anaerobic conditions are maintained by circulating a 80% N2, 10% H2, 10% CO2 gas mixture through alumina pellets coated with palladium. This study indicates that anaerobic conditions obtained in this chamber are sufficient for recovery of obligate anaerobes.

Water quality dependence on the depth of the vadose zone in SAT-simulated soil columns

2005 ◽  
Vol 5 (1) ◽  
pp. 17-24 ◽  
Author(s):  
W. Cha ◽  
H. Choi ◽  
J. Kim ◽  
J. Cho
Keyword(s):  
Water Quality ◽  
Vadose Zone ◽  
Unsaturated Zone ◽  
Phosphate Removal ◽  
Soil Aquifer Treatment ◽  
Soil Columns ◽  
Nitrogen And Phosphorus ◽  
Aquifer Characteristics ◽  
Zone Depth ◽  
Flooding Period

Three soil aquifer treatment (SAT) columns were operated for five months to investigate the dependence of the treated water quality upon the depth of unsaturated vadose zone in terms of its organics, nitrogen and phosphorus contents. It was found that DOC removal was independent of the unsaturated vadose zone depth except during the initial flooding period when the effluent was injected into each column. From tests to study the nitrate profile, it was found that the pattern of nitrification was dependent on the depth of the unsaturated zone during the initial periods of SAT flooding. However, no further nitrification occurred at the end of the flooding since the injection of the effluent continued to provide a high loading concentration to the SAT columns. The lack of phosphate removal in this study indicates that its removal is more dependent upon the soils and aquifer characteristics than on the depth of unsaturated zone.

Conception of vadose zone research in the area of Goczałkowice reservoir.

2013 ◽  
Vol 2 (1) ◽  
pp. 22-26
Author(s):  
Joanna Czekaj ◽  
Kamil Trepka
Keyword(s):  
Vadose Zone ◽  
Unsaturated Zone ◽  
Vertical Profile ◽  
Structural Model ◽  
Historical Data ◽  
Integrated System ◽  
Nitrate Transport ◽  
Strategic Research ◽  
Research Site ◽  
Observation Wells

Abstract Goczałkowice reservoir is one of the main source of drinking water for Upper Silesia Region. In reference to Water Frame Directive matter since 2010 the strategic research project: „Integrated system supporting management and protection of dammed reservoir (ZiZoZap)”, which is being conducted on Goczałkowice reservoir, has been pursued. In the framework of this project complex groundwater monitoring is carried on. One aspect is vadose zone research, conducted to obtain information about changes in chemical composition of infiltrating water and mass transport within this zone. Based on historical data and the structural model of direct catchment of Goczałkowice reservoir location of the vadose zone research site was selected. At the end of November 2012 specially designed lysimeter was installed with 10 MacroRhizon samplers at each lithological variation in unsaturated zone. This lysimeter, together with nested observation wells, located in the direct proximity, create the vadose zone research site which main aim is specifying the amount of nitrate transport in the vertical profile.

Reductive transformation of tetrachloroethylene to ethylene and ethane by an anaerobic filter

1997 ◽  
Vol 36 (6-7) ◽  
pp. 125-132 ◽  
Author(s):  
Toshiya Komatsu ◽  
Jun Shinmyo ◽  
Kiyoshi Momonoi
Keyword(s):  
Electron Donor ◽  
Laboratory Scale ◽  
Groundwater Contaminants ◽  
Reductive Transformation ◽  
Filter System ◽  
Anaerobic Filter ◽  
Anaerobic Microorganisms ◽  
Chlorinated Ethylenes ◽  
Start Up ◽  
Low Concentrations

Tetrachloroethylene (PCE) is one of the most common groundwater contaminants in Japan. PCE can be completely dechlorinated to ethylene (ETY) and ethane (ETA) by anaerobic microorganisms in the presence of a suitable electron donor. This study was conducted to examine the feasibility of using an anaerobic filter for the degradation of PCE in a bioremediation process. Laboratory-scale anaerobic filters were operated at 25°C using ethanol as the electron donor. Rapid start-up of the reactors was achieved by using anaerobic completely PCE-dechlorinating enrichment cultures as the inoculum. During the continuous operating periods, low concentrations (2.8 mg/L) of PCE were almost completely dechlorinated to ETY and ETA at hydraulic retention times of 49-15 hours with 100 mgCOD/L of ethanol. PCE concentrations as high as 80 mg/L was dechlorinated to ETY with a relatively low supply (200 mgCOD/L) of ethanol. Results of this study suggest that the anaerobic filter system is a feasible bioremediation process for the cleanup of groundwater which is contaminated by chlorinated ethylenes.

scholarly journals Anaerobic Conditions Induce Expression of Polysaccharide Intercellular Adhesin in Staphylococcus aureus and Staphylococcus epidermidis

2001 ◽  
Vol 69 (6) ◽  
pp. 4079-4085 ◽  
Author(s):  
Sarah E. Cramton ◽  
Martina Ulrich ◽  
Friedrich Götz ◽  
Gerd Döring
Keyword(s):  
Staphylococcus Aureus ◽  
Staphylococcus Epidermidis ◽  
Biofilm Formation ◽  
Extracellular Polysaccharide ◽  
Growth Conditions ◽  
Anaerobic Conditions ◽  
Anaerobic Environment ◽  
Specific Mrna

ABSTRACT Products of the intercellular adhesion (ica) operon in Staphylococcus aureus and Staphylococcus epidermidis synthesize a linear β-1,6-linked glucosaminylglycan. This extracellular polysaccharide mediates bacterial cell-cell adhesion and is required for biofilm formation, which is thought to increase the virulence of both pathogens in association with prosthetic biomedical implants. The environmental signal(s) that triggers ica gene product and polysaccharide expression is unknown. Here we demonstrate that anaerobic in vitro growth conditions lead to increased polysaccharide expression in both S. aureus and S. epidermidis, although the regulation is less stringent inS. epidermidis. Anaerobiosis also dramatically stimulates ica-specific mRNA expression inica- and polysaccharide-positive strains of both S. aureus and S. epidermidis.These data suggest a mechanism whereby ica gene expression and polysaccharide production may act as a virulence factor in an anaerobic environment in vivo.

Organic Acids and Anaerobic Microorganisms in the Contents of the Cholesteatoma SAC

1983 ◽  
Vol 92 (1) ◽  
pp. 91-96 ◽  
Author(s):  
Yukiko Iino ◽  
Tomonori Takasaka ◽  
Etsuro Hoshino ◽  
Yutaka Kaneko ◽  
Sachiko Tomioka ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Organic Acids ◽  
Volatile Fatty Acids ◽  
Chromatographic Technique ◽  
Anaerobic Conditions ◽  
Clostridium Species ◽  
Anaerobic Microorganisms ◽  
Aerobic And Anaerobic ◽  
Aerobic And Anaerobic Conditions

Organic acids in the contents of the cholesteatoma sac from 28 cases were studied by gas chromatographic technique. Five volatile fatty acids (acetate, propionate, isobutyrate, butyrate and isovalerate) and lactate were detected in large amounts, which may lower the pH of the cholesteatoma content. These acids were considered to be derived from products of anaerobic microorganisms. Therefore, the contents from 12 cases were cultured anaerobically in a glove box. Obligate microorganisms were identified in 92% of the cases and Peptococcus, Bacteroides, and Clostridium species were frequently isolated. In vitro, such obligate anaerobes produced various organic acids from the cholesteatoma content. Facultatives such as Staphylococcus aureus and Proteus mirabilis produced acetate in the content under aerobic and anaerobic conditions, whereas no organic acid was produced by Pseudomonas aeruginosa. Organic acids in the cholesteatoma content could be fermentative products made by the microorganisms, anaerobes and facultatives, which use the content as a substrate for acid production.

Influence of Different Salts on the Degradation of Trichloroethylene under Reductive Condition

2011 ◽  
Vol 356-360 ◽  
pp. 1689-1692
Author(s):  
Feng Na Ma ◽  
Qing Jun Meng ◽  
Guo Jun Wu ◽  
Ai Qin Shan
Keyword(s):  
Electron Donor ◽  
Anaerobic Condition ◽  
Anoxic Condition ◽  
Trivalent Iron ◽  
Anaerobic Conditions ◽  
Iron Salts ◽  
Anoxic Environment ◽  
Mixed Salts ◽  
Tce Degradation

The effect of TCE cometabolism degradation with glucose as electron donor on reduction progress was investigated with enriched nitrate, sulfate, trivalent iron and their mixtures under anoxic or anaerobic conditions. The removal effect of TCE was found to be better in anoxic environment; TCE degradation was inhibited by the addition of trivalent iron salts and the mixed salts under anoxic condition or strongly inhibited by nitrate under anaerobic condition; promoted by the addition of trivalent iron salts under anaerobic condition; little inhibited by the addition of nitrate and sulfate under anoxic condition or sulfate and the mixed salts under anaerobic condition.

scholarly journals Assessing tungsten transport in the vadose zone: From dissolution studies to soil columns

Chemosphere ◽  
2012 ◽  
Vol 86 (10) ◽  
pp. 1001-1007 ◽  
Author(s):  
Gulsah Sen Tuna ◽  
Washington Braida ◽  
Adebayo Ogundipe ◽  
David Strickland
Keyword(s):  
Vadose Zone ◽  
Soil Columns ◽  
Dissolution Studies
Sign in / Sign up

Export Citation Format

Share Document