Treatment method of ammonia nitrogen exceeding the standard in sewage treatment

There are many methods, such as inflection point chlorination, chemical precipitation, ion exchange, stripping and biological deamination. These technologies can be divided into physical and chemical methods and biological nitrogen removal technologies.

Biological nitrogen removal.

The process of removing ammonia nitrogen by microorganisms needs two stages.

The first stage is nitrification, in which nitrifying bacteria and nitrifying bacteria transform ammonia nitrogen into nitrite nitrogen and nitrate nitrogen under aerobic conditions. The second stage is denitrification process. Under anaerobic or anoxic conditions, nitrate nitrogen and nitrite nitrogen in sewage are reduced and converted into nitrogen by denitrifying bacteria (various heterotrophic and autotrophic microorganisms).

In this process, organic substances (methanol, acetic acid, glucose, etc. ) is oxidized to provide energy for electron donors.

Common biological nitrogen removal processes can be divided into three categories, namely, multi-stage sludge system, single-stage sludge system and biofilm system.