Membrane-bioreactor system for treatment of nitrates in pickling process wastewater
An innovative high efficient process for biological treatment of wastewater from pickling lines with a high nitrate-concentration in a new membrane-bioreactor has been developed. Compared to other processes for treatment of high concentrated nitrate wastewater, like reverse osmosis or ion exchange, nitrate will be converted into gaseous nitrogen, carbon dioxide and biomass. The developed treatment process reduces in a cost-effective way nitrates in pickling wastewater. The cost analysis showed that for exemplarily pickling process effluents the treatment costs amount to EUR 1 to 9 per m3 process water with nitrate concentrations up to 6,750 mgNO3-N/L. The very stable biological treatment process is a useful completion of the process for common pickling bath regeneration plants. All results of the research project were used for scale up of the treatment process to industrial scale. For this a control concept and a nitrate online measurement were tested and implemented in an operational bypass membrane bioreactor system. Because of higher investment and operational costs as well as membrane fouling the use of a microfiltration membrane for biomass retention should be decided specific under economical aspects. Alternative possibilities for biomass retention were discussed. The developed biological treatment process reduces nitrate in process water cost effective. It is a very good alternative to the expensive total regeneration of pickling acids. In combination with common processes for pickling bath regeneration the developed biological treatment process helps to avoid any nitrate emissions of the pickling with nitric acid.
Bibliographic Reference: EUR 22430 EN (2006), 195 pp. Euro: 25
Availability: Katalogue Number: KI-NA-22430-EN-S The paper version can be ordered online and the PDF version downloaded at: http://bookshop.europa.eu
ISBN: ISBN: 92-79-03743-9
Record Number: 200719305 / Last updated on: 2007-07-10
Original language: en
Available languages: en