Figure 1. Basic process flow diagram of the WWTP in Finnland upgraded by LEVAPOR
Nitrification of municipal effluents in fluidised bed reactors using immobilised microorganisms 1. The problem Existing municipal effluent treatment plants designed earlier for the BOD removal are usually not suitable for nitrification at low temperatures, because of : Small plant dimensions and low sludge age, respectively Biokinetical reasons. Consequences are that in the cases of nitrification expensive plant extensions are required. 2. Our problem solution results in Plants being upgraded into fluidised bed reactors using microorganisms immobilised on adsorbing LEVAPOR-carrier. Nitrifying bacteria immobilised on adsorbant carriers become more robust and efficient, produce lower quantities of excess sludge and are able to maintain their activity even after a storage over 12 months. 3. EXAMPLES: A. Upgrading of a small municipal WWTP with aerated basin of 45 m³, for nitrification in winter, by filling it with 12 vol.% of LEVAPOR carrier As a possible alternative to plant extension, it was considered to establish the nitrification by a susequent WWTP- upgrading via immobilisation of nitrifying sludge on 12 vol.% of adsorbing LEVAPOR-carrier. Results: After addition into the basin the carrier cubes became colonised and fluidised directly and despite the low temperatures (November) the nitrification was established at 17°C within two to three weeks and kept efficient achieving 70 to 80% nitrification over several months, despite even the lower temperatures in December (12 °C). Summary Immobilising the activated sludge, nitrification was established within 2 to 3 weeks. The nitrification remained stable and efficient, even at lower temperatures, of 8 to 13°C with increased volumetric N-loading rates. The existing aeration system was proven as sufficient for almost a complete fluidisation of the colonised carrier cubes. Removal of excess biomass from the surface of the carrier cubes occurred automatically by fluidisation without any additional measure. B. Nitrification and removal of hazardous pollutants from municipal effluents ( pilot plant trials) Comparison of immobilised -LEVAPOR-carrier - vs. suspended sludge Pilot plants In two parallel operated fluidised bed reactors, each of 3,1 m³, nitrification and hazardous pollutant removal of immobilised and suspended biomass have been compared. In addition to higher degree of nitrification and denitrification ( due to inner pores of carrier cubes ), immobilised biomass achieved also a remarkably higher removal of polycondensed aromatic compounds.
LEVAPOR GmbH • Kölner Str. 38 • D-51379-Leverkusen • Geschäftsführung Dr. Imre Pascik • Telefon: +49 (0) 2173 - 93 87 15 • Mobil +49 (0) 177 - 786 55 33 • e-mail:
WAS IST LEVAPOR? LEVAPOR - Eigenschaften und Anwendungsformen LEVAPOR-C für Wirbelbettreaktoren LEVAPOR-F für Anaerobprozesse Typen und Eigenschaften Die LEVAPOR-Story EINSATZGEBIETE LEVAPOR in der Abluftbehandlung in Rieselbettreaktoren Biologische Behandlung der Abluft eines Abwasserpuffers Biologische Behandlung der Abluft einer Lagerhalle für Kunststoffabfälle Biologische Behandlung der Abluft aus der Schlammbehandlung Biologische Behandlung von Styrol enthaltenden Abluft LEVAPOR in der Abwasserbehandlung LEVAPOR in CSB-Elimination Behandlung von toxischen Abwässern der Zellstoffherstellung Behandlung von komplexen Abwässern aus der Herstellung von Feinche Behandlung von agrochemischen Abwässern LEVAPOR im AOX-Bioabbau LEVAPOR für Nitrifikation Nitrifikation von Kommunalabwässern Nitrifikation of complex industrial effluents Nitrifikation von salzhaltigen inhibierenden Chemieabwässern Nitrifikation von salzhaltigem Chemieabwasser Nitrifikation in Hauskläranlagen LEVAPOR für Kommunen Nitrification of municipal effluents LEVAPOR bei Hauskläranlagen LEVAPOR-Abluftbehandlung für Bioreaktoren Biofilter Wirbelbettreaktor mit LEVAPOR-Trägermaterial NEWS IMPRESSUM LINKS KUNDENBEREICH