کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4415855 1307761 2007 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Biological denitrification of high strength nitrate waste using preadapted denitrifying sludge
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم محیط زیست شیمی زیست محیطی
پیش نمایش صفحه اول مقاله
Biological denitrification of high strength nitrate waste using preadapted denitrifying sludge
چکیده انگلیسی

Denitrification of synthetic high nitrate waste containing 9032 ppm NO3–N (40 000 ppm NO3) in a time period of only 6 h has been achieved in our previous study using activated sludge. The activated sludge culture was acclimatized by a stepwise increase in the nitrate concentration of synthetic waste. In the present work, studies were carried out on the changing microbial population of the sludge and the physiology of nitrate metabolism during the various stages of adaptation process to high strength synthetic nitrate waste. During the course of adaptation, with an increase in the nitrate concentration, a sharp increase in the number of denitrifiers was found with an equally rapid decrease in the nitrifying community. Two key enzymes involved in the first two steps of the denitrification process were also studied during this period. The results of the study suggest that specific enzyme levels increase as the activated sludge adapts itself to higher nitrate concentrations. Biological denitrification of high nitrate waste is a slow process and to increase the rate of denitrification, parameters such as pH, temperature, C:N and biomass concentration of the process were optimized using orthogonal array method. Optimized conditions increased the specific nitrate reduction rate by 54% and specific nitrite reduction rate by 45%.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemosphere - Volume 67, Issue 8, April 2007, Pages 1612–1617
نویسندگان
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