Culturing method for dominant nitrosation bacterial community

Abstract

The invention relates to a culturing method for a dominant nitrosation bacterial community. The culturing method comprises the following three culturing stages: stage 1, enriching a mixed bacterial community of nitrosomas and nitromonas, wherein a microbial growth promoter A is used in the process of enrichment; stage 2, carrying out nitromonas elutriation by using a microbial growth promoter D and a high-temperature culture and normal-temperature culture alternate method so as to gradually improve the dominance of nitrosomas and beginning third-stage culture when a nitrosation rate is greater than 50%; and stage 3, reducing the content of dissolved oxygen or increasing a pH value, carrying out further nitromonas elutriation and stability domestication of nitrosomas by using the microbial growth promoter D and terminating culture when the nitrosation rate is stabilized and is 65% or more so as to obtain the dominant nitrosation bacterial community. The culturing method provided by the invention overcomes the problems of instability of partial nitrification in practical application, can shorten the starting time of nitrifying process, rapidly changes the process of a nitrifying reaction, broadens the application scope of partial nitrification and provides guarantee for actual application of a partial nitrification process to real projects.

Description

Technical field [0001] The invention belongs to the technical field of sewage biological treatment, and specifically relates to a method for culturing a nitrosation dominant bacterial group. Background technique [0002] The biological denitrification of wastewater mainly relies on the combined action of nitrifying bacteria and denitrifying bacteria in the activated sludge to finally convert various forms of nitrogen in the sewage into gaseous nitrogen and escape 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 completed 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 entire biological denitrification process can pass NH 3 -N is converted to NO 2 -N then converted to N 2 Way to complete. [0003] Shor...

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.

CN102311918A discloses a method for cultivating nitrosative-dominant bacterial flora, which only relies on external conditions for enrichment and cultivation, and the time is relatively long

[0007] At present, short-cut nitrification uses factors such as low dissolved oxygen (DO), high temperature, high pH, ​​and inhibitory factors to control or screen the dominant nitrosative flora. Due to changes in conditions, the phenomenon of conversion from short-cut nitrification to full-range nitrification cannot be effectively controlled.

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