Method for culturing nitrosation dominant microflora

Abstract

The invention discloses a method for culturing a nitrosation dominant microflora, which comprises the following three culture stages: a first stage of enriching mixed microflora of nitrosobacteria and nitrobacteria; a second stage of elutriating nitrobacteria by using a high-temperature culture and normal-temperature culture alternating process, gradually improving the dominate position of the nitrosobacteria, and transferring into a third stage of culture when a nitrosation rate is more than 50 percent; and a third stage of changing the dissolved oxygen and pH condition to perform further elutriation of nitrobacteria and the stable domestication of nitrosobacteria till the nitrosation rate is stabilized over 65 percent. Thus, a culture period is finished, a microflora in which the nitrosobacteria take a dominate position is obtained, and the microflora is stored for later used. The method solves the problems of instability and the like in the actual use of short-process nitration, the start time of a nitration process can be shortened, a nitration reaction process can be changed quickly, the application range of short-process nitration can be expanded, and a guarantee is providedfor the actual use of the short-process nitration process in practical projects.

Description

technical field [0001] The invention belongs to the technical field of sewage biological treatment, and in particular relates to a method for cultivating nitrosative dominant bacterial groups. Background technique [0002] The biological denitrification of wastewater mainly relies on the joint action of nitrifying bacteria and denitrifying bacteria in activated sludge, and finally converts various forms of nitrogen in sewage into gaseous nitrogen and escapes from the water. From the perspective of nitrification process, ammonia nitrogen (NH 3 -N) is oxidized to nitrite nitrogen (NO 2 -N) and nitrate nitrogen (NO 3 -N) are two different reactions performed by two separate types of bacteria, which should be separable. From the perspective of denitrification process, NO 2 -N and NO 3 -N can be used as the final electron acceptor. Therefore, the whole biological denitrification process can be carried out by NH 3 -N converted to NO 2 -N is converted to N again 2 way to c...

AI Technical Summary

Problems solved by technology

However, in practical engineering applications, it is difficult to stably control the DO concentration within the required low concentration range. Once the DO concentration is high, the short-cut nitrification will transform into the full-range nitrification

CN1785843A discloses a method for short-range nitrification of wastewater with low C / N ratio and high concentration of ammonia nitrogen. The method uses the nitrification granular sludge cultivated by anaerobic granular sludge as an inoculum, and gradually increases the concentration of ammonia nitrogen in the substrate to realize it. Although oxygen granular sludge has the advantage of fast cultivation speed, in the subsequent aerobic short-cut nitrification process, there are still shortcomings in the transformation from short-cut nitrification to full-range nitrification.

Zu Bo et al. (Experiment on the enrichment of aerobic ammonium oxidizing bacteria in ordinary activated sludge, Journal of Chongqing University, 2005, 28 (2)) at pH 7.8-8.3, DO at 0.8-1.2mg / L, and temperature at 30± At 2°C, the enrichment of aerobic ammonia oxidizing bacteria was carried out by gradually increasing the concentration of ammonia nitrogen in the influent. This enrichment method can significantly increase the number of nitrosating bacteria, but the long-term Stability still needs to be further improved