Removal of 2-butoxyethanol gaseous emissions by biotrickling filtration packed with polyurethane foam

The removal of 2-butoxyethanol from gaseous emissions was studied using two biotrickling filters (BTF1 and BTF2) packed with polyurethane foam. Two different inoculum sources were used: a pure culture of Pseudomonas sp. BOE200 (BTF1) and activated sludge from a municipal wastewater treatment plant (BTF2). The bioreactors were operated at inlet loads (ILs) of 130 and 195 g m−3 hour−1 and at an empty bed residence time (EBRT) of 12.5 s. Under an IL of ∼130 g m−3 hour−1, BTF1 presented higher elimination capacities (ECs) than BTF2, with average values of 106 ± 7 and 68 ± 8 g m−3 hour−1, respectively. However, differences in ECs between BTFs were decreased by reducing the irrigation intervals from 1 min every 12 min to 1 min every 2 hours in BTF2. Average values of EC were 111 ± 25 and 90 ± 7 g m−3 hour−1 for BTF1 and BTF2, respectively, when working at an IL of ∼195 g m−3 hour−1. Microbial analysis revealed a significant shift in the microbial community of BTF1 inoculated with Pseudomonas sp. BOE200. At the end of the experiment, the species Microbacterium sp., Chryseobacterium sp., Acinetobacter sp., Pseudomonas sp. and Mycobacterium sp. were detected. In BTF2 inoculated with activated sludge, the denaturing gradient gel electrophoresis (DGGE) technique showed a diverse microbial community including species that was able to use 2-butoxyethanol as its carbon source, such as Pseudomonas aeruginosa and Pseudomonas putida as representative species. Although BTF1 inoculated with Pseudomonas sp. BOE200 and higher gas velocity (probably greater gas/liquid mass transfer rate) showed a slight improvement in performance, the use of activated sludge as inoculum seems to be a more feasible option for the industrial application of this technology

Biologische Sanierung von Carbochemie Altlasten; Teilverbund 1: Humizierung von PAK. Teilvorhaben 1/2: Bakterielle Metaboliten Schlussbericht

During bioremediation of poorly watersoluble contaminants of soil, the partial metabolism or cometabolism - besides the complete metabolization - to carbon dioxide and water - plays a pivotal role. The reaction products of these process may be excreted and used for chemical secondary reactions e.g. polymerisation reactions. Interestingly, a complete degradation of PAH in soil seems to be accompanied inevitably by incomplete metabolism, leading to formation of socalled 'bound residues'. One explanation could be the formation of covalent bonds between PAH metabolites and the soil matrix. Representative PAH metabolites were defined and structurally characterised. Anthracene and pyrene were studied most intensively and radioactively labelled metabolites were created thereof ("1"4C-labeling). These radioactively labeled metabolites can be used in tracer experiments to study their chemical and sorptive behaviour in defined soil matrices. A second aim is to study the extent and the kind of the alteration of soil structures during binding of PAH metabolites. Finally, the reversibility of these processes is to be studied. (orig.)SIGLEAvailable from TIB Hannover: F97B1671+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Mikrobielle Umsetzungen an Kohle und kohlerelevanten Strukturen. Teilvorhaben: Bakterieller Angriff auf Kohlepartialstrukturen sowie Kohlemodellsubstanzen Schlussbericht

The aims of the research project was to identify the possbilities of a microbial attack on coal model compounds. Investigations on the degradation of coal itself by bacteria in hampered by the failure to find appropriate bacteria and by the experimental difficulties in detection of such activities which are more common within the fungi. Secondly, production of compounds with potential commercial value was envisaged using coal model compounds as starting material. The positive outcome of these experiments gives rise to the possibility to generate a bunch of new substances from coal using biologically pretreated material or starting compounds generated by a chemical/physical pretreatment. (orig.)Ziel der Projektarbeiten war es, die Grundlagen zum Verstaendnis des mikrobiellen Abbaus von Modellstrukturen der Kohle zu legen. Die Kohle selbst ist einer exakten, direkten Untersuchung ihrer Bioabbaubarkeit nicht leicht zugaenglich. Gleichzeitig sollten komplexe Metabolite aus Kohle - relevanten Ausgangsverbindungen erzeugt werden. Die Ergebnisse lagen nahe, dass eine bakterielle Biodegradation von Kohlen im Gegensatz zu Pilzen, nicht erfolgreich sein wird. Hingegen eroeffnet sich ein grosses Potential bei der Darstellung von Verbindungen mit potentiellem Werkstoffcharakter unter Verwendung von pilzlichen Kohleabbauprodukten bzw. Produkten einer chemisch/physikalischen Vorbehandlung von Kohle. (orig.)SIGLEAvailable from TIB Hannover: F97B1783+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Untersuchungen zur biologischen Abluftreinigung von geruchsintensiver Abluft aus Klaeranlagen in Belebungsbecken Abschlussbericht

SIGLEAvailable from TIB Hannover: F02B1296+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Anwendung von Hochleistungsbiofiltern zur Reinigung styrolhaltiger Industrieabluft

A substantial reduction of the size of biofilters is achieved by employing optimized filter materials. This, in many cases, is a prerequisite for their use in industrial processes of waste air cleaning. An attractive field of application is the plastics manufacturing industries. Here, frequently high amounts of waste air loaded with aromatics are to be cleaned. As their concentration normally is considered to be too low for an efficient use of conventional procedures like thermic or catalytic processes, ''high performance biofilters'' (HPBFs) are playing an essential role. In our research project, we concentrated on the question whether HPBFs can be used under industrial conditions of strongly fluctuating concentrations of styrene and acetone. The operation of the pilot filter was run under downstream and upstream conditions. The investigations showed that HPBFs also under industrial conditions achieved very high elimination rates up to 150 g/m"3 filtermaterial and hour. That styrene is actually degraded to CO_2 and water was shown by analysis of the offgas and of the filter material. No oligomeric or polymeric material out of styrene was found. Accordingly the presence of styrene degrading microorganisms as well as biological activity of the filtermaterial was unequivocally demonstrated. (orig.)Mit Hilfe einer Biofilter-Anlage im Pilotmassstab wurde bei einem Industriebetrieb aus der Kunststoffbranche (Herstellung von GFK-Teilen) untersucht, ob Biofilter auch unter Hochlastbedingungen fuer die Reinigung industrieller Abluft eingesetzt werden koennen. Die styrolhaltige Abluft wurde der Biofilter-Anlage bei verschiedenen Belastungen zugefuehrt. Dadurch konnten mehrere Betriebszustaende von Normallast (laminare Stroemung) bis zum Hochlastbereich (turbulente Stroemung) variiert werden. Weitere Untersuchungsvarianten waren der Einsatz von zwei verschiedenen optimierten Filtermaterialien, aufwaerts- und abwaerts durchstroemte Filter sowie eine Betriebsweise mit und ohne Vorkonditionierung. Die Untersuchungen ergaben unter anderem, dass Hochleistungsfilter auch fuer industrielle Abluft, die relativ schlecht abbaubares Styrol enthaelt, anwendbar sind. Die Eliminationsleistung war im untersuchten Bereich nahezu unabhaengig von der Verweilzeit und im wesentlichen nur abhaengig von der spezifischen Filterbelastung. Es wurden Eliminationsleistungen von bis zu 150 org. C/m"3 Filtermaterial und Stunde erreicht. Der Betrieb als Hochleistungsfilter erfordert jedoch mehr Ueberwachung und Wartung als bei niedrig belasteten Biofiltern. Durch begleitende Untersuchungen zur CO_2-Emission und Analysen des Filtermaterials auf Styrol-Komponenten wurde gezeigt, dass Styrol tatsaechlich abgebaut wird und nicht im Filter polymerisiert. Die abbauenden Mikroorganismen wurden zum Teil isoliert und charakterisiert. Die biologische Aktivitaet des Filtermaterials wurde demonstriert. (orig.)Available from TIB Hannover: RO 2590(134) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLELand Baden-Wuerttemberg, Stuttgart (Germany)DEGerman