In the biological treatment process of sewage, the factors affecting the microbial activity can be divided into two categories: matrix and environment. The matrix includes nutrients, such as carbon-based organic compounds, that is, carbon source substances, nitrogen sources, phosphorus sources and other nutrients, and trace elements such as iron, zinc, and manganese.In addition, Inner Mongolia wastewater treatment also includes some toxic and harmful chemicals Substances such as phenols and benzenes also include some heavy metal ions such as copper, cadmium, and lead ions.
The biological pond is a place for microbial purification of sewage, which contains a large number of beneficial microorganisms, which can absorb heavy metal ions, eutrophic substances and other harmful substances in the sewage, so that the sewage can be cleaner and the sewage purification can be accelerated. What is the role of aerobic, anoxic, and anaerobic tanks in a sewage treatment plant?
First, the aerobic pool is to create an aerobic environment (dissolved oxygen is about 4mg / L), which is conducive to the growth of good microorganisms. Its role is to adsorb and degrade organic matter by aerobic activated sludge. Activate activated sludge to aerobic respiration to further decompose organic matter into inorganic matter. Removes most of the organic matter such as cod, ammonia nitrogen in sewage, and removes pollutants. The good operation is to control the oxygen content and other optimal conditions of the microorganisms, so that the microorganisms can perform aerobic respiration with the greatest benefits. Oxidizing compounds of carbon in organics are generally oxidized to CO2 and H2O; nitrogen is oxidized to nitrite nitrogen and nitrate nitrogen; phosphorus is oxidized to phosphate; at the same time, polyphosphate bacteria absorb in aerobic environment several times Phosphate under anaerobic conditions.
Second, the hypoxic tank is to create a hypoxic environment (the dissolved oxygen is less than 0.5mg / L), which refers to the reaction tank without dissolved oxygen but with nitrate. Conducive to the growth of deficient microorganisms. The role of Inner Mongolia wastewater treatment is to adsorb and degrade organic matter by activated sludge. The nitrite nitrogen and nitrate nitrogen in the reflux mixture are usually released under the action of denitrifying bacteria.
3. An anaerobic tank is to create an anaerobic environment (dissolved oxygen is about zero), which refers to a reaction tank without dissolved oxygen and no nitrate. Conducive to the growth of vegetative microorganisms. Its role is to adsorb and degrade organic matter in activated sludge. In the anaerobic tank, the role of anaerobic bacteria is used to hydrolyze, acidify and methanate organic matter, remove organic matter in wastewater, and improve the biodegradability of sewage, which is beneficial to subsequent aerobic treatment.
Summary: The aerobic tank is to maintain the dissolved oxygen content in the water at about 4mg / l through aeration and other measures, which is suitable for the growth and reproduction of aerobic microorganisms, so as to treat the structures of pollutants in the water. Because decomposition and consumption of dissolved oxygen make the water body almost free of dissolved oxygen, it is suitable for anaerobic microbial activities to treat structures in the water. Hypoxic ponds are insufficiently aerated or non-aerated but the content of pollutants is low, suitable for aerobic and both Structures where oxygen microorganisms live. Different oxygen environments have different microbiomes. Microbes also change their behavior when the environment changes, so as to achieve the purpose of removing different pollutants. At present, many projects in Inner Mongolia sewage treatment plant upgrading and other projects will use the MBBR process, which can effectively enhance the role of biological reaction unit in sewage treatment.