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Urea and ammonia are mostly present in wastewaters from  nitrogenous fertilizer  industries. Urea can  not be oxidized  by usual oxidation methods, microbiological  hydrolysis of urea is necessary for removal of urea from wastewater.  Biological degradation of urea is a two staged process; (i) urea hydrolysis  and (ii) ammonia stripping/nitrification-denitrification.  Microbiological  hydrolysis of urea through biohydrolyzer  removes urea from fertilizer effluents , in which ,ureolytic bacteria Bacillus Pasteurii  converts urea into ammonia   and carbon  dioxide  through ammonium carbonate  as an   intermediate  product.  Removal  of ammonia is  either  by stripping or converting into nitrate on nitrification  by chemoautotraphic  bacteria  Nitrosomonas sp.  and further  by Nitrobacter  sp. into nitrate. On dentirification, nitrate is finally converted  into nitrogen  gas by means of heterotrophic bacteria.  Based on earlier laboratory  investigations,  urea  bio-hydrolyser  was designed, installed  and commissioned  in fertilizer  industry  as  additional  full scale unit to treat urea and ammonia bearing wastewaters. Ammonia stripped effluent was mixed with  septic tank effluents from industry and township sewage and routed through various lagoons cultured with algae - chlorella to minimize nitrogen.  Evaluation of full scale urea bio-hydrolyser and effluent treatment plant before and after modifications at ETP is discussed  in this paper.


Urea ammonia nitrogenous fertilizer industry microbiological treatment nitrification urea bio-hydrolysis

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How to Cite
P. P. Pathe, Nandy, T., Kaul, S. N., Deshpande, C. V., & Szpyrkowie, L. (2001). Microbial Degradation of Urea from Urea Bearing Wastewaters. Environment Conservation Journal, 2(1), 25–32.


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