Description: The objective of this project is to investigate treatment methods for an economical and effective pre-treatment of the NF concentrates before recycling them into the biological stage. The COD compounds are cracked with the use of oxidation processes as concentrate treatment. After the oxidation of the residual COD, the bio degradation of the cracked molecules in the biological stage is possible. Different oxidation processes are considered: - Ozone treatment - Fentons process (Hydrogen peroxide oxidation with Fe2+ ions as catalyst) - Wet oxidation with H2O2 supported by UV-light - Electrochemical oxidation. These experiments are supplemented by coagulation / precipitation trials with different precipitants. Direct COD removal in the concentrated stream is possible as a consequence of the precipitation processes. Disadvantage of this process is the accumulation of sludge which must subsequently be disposed. Results: Trials showed that the possible aerobic bio degradation after the treatment varies between: - 0-10 percent Electrochemical oxidation, precipitation and untreated concentrate - 10-30 percent Ozonation and wet oxidation - 30-50 percent Fentons process (with a minimum H2O2/CSB ratio of 0.7, which leads in combination with high COD concentrations to increased cost of operation). The anaerobic degradation ranged in most experiments between 5 to 20 percent. With precipitation processes a maximum COD reduction of 30-50 percent is possible. Precondition is the use of at least 1-3 g/l of precipitant, due to the high concentration level of salt, colloids and organic COD. Promising results has already been gathered, further trails with different concentrate samples will follow in the next months.
SupportProgram
Origins: /Bund/UBA/UFORDAT
Tags: Kabeljau ? Recycling ? Wasserstoffperoxid ? 4. Reinigungsstufe ? Verschlammung ? Fluss ? Nanofiltration ? Aerobe Bedingungen ? Katalysator ? Salz ? Anaerober Abbau ? Abwasserbehandlung ? Kolloid ? Strafrecht ? Verfahrenskombination ? Wirkung ? Oxidation ? Studie ? Abbau ? Aufbereitungstechnik ? Niederschlag ? Rückstand ? Abwasser ? Entfernung ? Einsatz ? Ergebnis ? Experiment ? Gerinnung ? Ionen ? Konzentrat ? Lernziel ? Methode ? Nachbehandlung ? Probe ? Projekt ? Präzipitation ? Verarbeiten ? Verbindung ? Verringerung ? Vorbehandlung ? biologisch ? fördern ? größt ?
Region: Bavaria
Bounding boxes: 11.5° .. 11.5° x 49° .. 49°
License: cc-by-nc-nd/4.0
Language: Englisch/English
Time ranges: 2007-08-01 - 2009-07-31
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