Culture method of denitrifying bacteria taking N2O as end product

Abstract

The invention discloses a culture method of denitrifying bacteria taking N2O as an end product. The method comprises the following steps: pumping sewage containing a carbon source, nitrate nitrogen and nutrient elements required by growth of microorganisms into an SBR (sequencing batch reactor) inoculated with denitrifying sludge through a water inlet peristaltic pump; performing denitrifying reaction on sludge-sewage mixed liquor in the denitrifying SBR in a nitrogen state; gradually reducing the C / N of wastewater entering the denitrifying SBR; blowing N2O generated in the SBR from the SBR toa gas collection system in a nitrogen aeration manner; when the pH value tends to be stable, forcibly performing precipitation and drainage and terminating reaction to make the SBR in an idle state;repeating operations of the SBR to keep culturing the denitrifying bacteria taking N2O as the end product. According to the method, the denitrifying bacteria taking N2O as the end product of a denitrifying process can be screened and cultured, N2O in the denitrifying process can be accumulated, and the method is favorable for recycling the energy substance N2O.

Description

technical field [0001] The invention relates to the field of water treatment, in particular to a 2 O is the cultivation method of denitrifying bacteria with final product. Background technique [0002] Denitrification is an important part of the nitrogen cycle. Denitrifiers undergo HADH in anoxic environment 2 →FAD→quinone→cytochrome b→Mo→NO 3 - The electron transfer process will NO 3 - Reduction to NO by extramembrane nitrate reductase and intramembrane nitrate reductase 2 - ; followed by NO 2 - It is reduced to NO under the catalysis of nitrite reductase Nir. It has been considered for a long time that N 2 O is NO 2 - It is known that NO was discovered as a product in the late 1980s; NO is reduced to N under the action of nitric oxide reductase Nor bound in the membrane 2 O; final N 2 O is reduced to N by the action of nitrous oxide reductase Nos located between the cell wall and the cell membrane 2 . N 2 O is an intermediate product of the denitrification...

AI Technical Summary

Problems solved by technology

[0003] During the denitrification process, denitrifying bacteria are facultative bacteria. When DO exists in the environment, they will preferentially use oxygen as the electron acceptor for respiration, and the Nos enzyme is easily inhibited by oxygen and inactivated; when the C / N is low , during the denitrification process competes for the internal carbon source electron donor, and the Nos enzyme has weak competitive ability, which will also lead to the inhibition of the Nos enzyme. All of the above will cause incomplete denitrification, resulting in N 2 O accumulates as a denitrification species product

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