Biological denitrification of wastewater-A Mini Review on Carbon Source
Srinu Naik. SY. Pydi Setty
National Institute of Technology
摘要：A comparative study on the use of carbon sources as supplementary source to enhance denitrification in primary and secondary anoxic zones is reported. Denitrification is a process in which the oxidized nitrogen substances, i.e. nitrates and nitrites are reduced to nitrogen gas, such as N2O and N2 , when a proton donor （energy source） is available. Nitrate contamination is one of the major problems in groundwater, which is increasingly becoming a threat to groundwater supplies. Nitrate in drinking water for animal and human consumption is not recommended for health reasons. The World Health Organization has set a limit of 10 mg/L NO3-for human consumption and 100 mg/L NO3-for animals. Nitrogen in groundwater results from human excreta, ground garbage and industrial effluents, particularly from food processing plants. The addition of external carbon source helps in increasing denitrification rates and enhances the nitrogen removal. Nitrates cause cancer, methemoglobinemia （blue baby syndrome）, hypertension and thyroid hypertrophy and eutrophication in plants. In most biological denitrification systems, the nitrate polluted wastewater （e.g. domestic sewage） contains sufficient carbon source to provide the energy source for the conversion of nitrate to nitrogen gas by the denitrifying bacteria. The groundwater, in which the nitrate contents may be as high as 100 mg/L with low dissolved carbon content, an additional proton acceptor is required. The review addresses the state of the art of each electron donor candidate for its potential application to the treatment of industrial wastewater containing nitrate.
International Conference on Computer Graphics,Simulation and Modeling（ICGSM’2012）;International Conference on Production,Materials and Automobile Engineering（ICPMAE2012）;International Conference on Advances in Transformers and Electronics Engineering（ICATEE’2012）;International Conference on Chemical,Environmental Science and Engineering（ICEEBS’2012）;International Conference on Business Intelligence and Humanities（ICBEBS’2012）;International Conference on Biological,Biomedical and Pharmaceutical Sciences（ICCEPS’2012）