جستجوی مقالات مرتبط با کلیدواژه « فرایند شارون » در نشریات گروه « مهندسی شیمی، نفت و پلیمر »

Recently, several new processes for nitrogen removal have been developed. Conventional microbial nitrogen removal includes two separate steps of nitrification and denitrification. In the nitrification step, the conversion of NH4+ to NO2- and further to NO3- will be happened and in the denitrification step nitrate will be converted to gaseous nitrogen with nitrite as intermediate component. The presence of different autotrophic and heterotrophic microorganisms in these two steps and different aerobic and anaerobic conditions needed for nitrification and denitrification, make require the use of two separate reactors with independent clarifier. The new processes are based on partial nitrification of ammonium to nitrite combined with anaerobic ammonium oxidation that decreases the carbon source and oxygen demand. Some of these processes include the single reactor that decrease the costs, needs lesser space and produce lesser sludge. Among these new processes, we can mention system for high ammonia removal over nitrite (SHARON), the anaerobic ammonium oxidation (ANAMMOX) process, the completely autographic nitrogen removal over nitrite (CANON) process, and the combined ANAMMOX- SHARON. In this paper, different biological nitrogen removal methods have been presented and a comparison has been made with the criteria such as N2O production, needs of pH control, dissolved oxygen concentration, chemical oxygen demand, sludge production, percentage of nitrogen removal and economical conditions.