Abstract
In many experiments, a partial nitrification device is initiated with the use of highly active nitrating sludge because of the large number of nitrifying bacteria. Ammonia-oxidizing bacteria (AOB) are more adaptable to low-dissolved oxygen environments than nitrite-oxidizing bacteria (NOB). NOB activity was inhibited when the dissolved oxygen (DO) levels were decreased, causing the nitrate-nitrogen concentration to gradually decrease in the effluent and the nitrite-nitrogen concentration to gradually increase, achieving the accumulation of nitrous nitrogen. In this experiment, a sequencing batch reactor (SBR) was used to suppress NOB activity at a given pH while maintaining DO at a very low level so that the ammonia–water reaction mainly occurred in the device, and then the mud and water separated. Compared with other experiments, this approach can occur in 25 days, and it runs stably for more than two months until the device closes when the ammonia-nitrogen concentration is about 170 mg/L. This experiment also compared the difference between the pH change at the beginning of the device operation and after the device was stable. In order to increase the efficiency of bacterial appreciation, supplementing NaHCO3 increased the HCO3− concentration by 300 mg/L on the 25th day. It was found that some nitrification reactions still occurred, but they were not enough to destabilize the device. The nitrosate accumulation efficiency still gradually increased, and the average nitrite accumulation efficiency was 87.25% after NaHCO3 supplementation.
Highlights
The question of how to remove nitrogen in sewage economically and efficiently has always been a hot topic in international research
PH, dissolved oxygen, and other factors change, the activity of the nitrite-oxidizing bacteria (NOB) is inhibited and the Ammonia-oxidizing bacteria (AOB) become more abundant than the NOB [7]
The effect on the partial nitrification process was observed by controlling dissolved oxygen (DO) under extremely low conditions, and through higher pH and alkalinity
Summary
The question of how to remove nitrogen in sewage economically and efficiently has always been a hot topic in international research. PH, dissolved oxygen, and other factors change, the activity of the NOB is inhibited and the AOB become more abundant than the NOB [7]. This allows nitrite-nitrogen to accumulate in the water. There have been many studies on controlling the short-range nitrification process by controlling dissolved oxygen (DO) [8,9]. In this experiment, the effect on the partial nitrification process was observed by controlling DO under extremely low conditions, and through higher pH and alkalinity. The main purpose of this study is to observe the operating characteristics of the partial nitrification device initiated by supplementing the inorganic carbon source and pH control
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call