| Nitrogen removal by CarbonFiber
Biological Nitrogen Removal Method
| There is a biological nitrogen removal methd in order to remove water
pollutant nitrogen from wastewater. In the public sewage treatment facilities,
the industrial wastewater treatment facilities, and the livestock wastewater
treatment facilities, the activated sludge process is generally carried
out, and organic matter is broken through aeration and the action of aerobic
bacteria in activated sluge treatment tank. However, although anmonia nitrogen
NH4-N is biologically oxidized to nitrate NO3-N from nitrite NO2-N by nitrifying
bacteria activated by aeration, nitrogen N is not removed as it is accumulated
in the aeration tank and it remains as toal nitrogen TN. In order to decompose
nitrate NO3-N to nitrogen N, it is necessary to set up an anaerobic tank
in the latter process, and to decompose nitrate NO3-N to nitrogen N2 with
denitrifying bacteria which is anaerobic bacteria. However, in many existing
facilities and small sized ones, great amount of finantial burdens are
necessary and it is physically difficult to biologically remove nitrogen
by constructing an anaerobic tank.
|Accumulation of nitric oxide in activated sludege treatment
| To decompose nitrate NO3-N into nitrogen N2, it is effective to biological
remove nitrogen in the aeration tank. In the activated sludge treatment
tank, if an anaerobic state is created and denitrifying bacteria are activated,
ammonia NH4→nitrite NO2→nitrate NO3→nitrogen N2 + H2O is promptly reacted.
Since nitrogen N2 diffuses into the atmosphere, nitrogen is removed from
the wastewater. Moreever, since nitrogen oxides are not accumulated, the
generation of intense greenhouse gas dinitrogen monoxide NO2 is suppressed.
|Principle of Biological Nitrogen removal
★Nitrogen Removal by MiraCarbon
| CarbonFiber water purification material with its large surface area that
adheres microorganisms will decompose and remove nutrients such as organic
matter, nitrogen and phosphorus. CarbonFiber when placed in water will
spread and will make a carbon mass, making the surface area in aerobic
condition with nitrifying bacteria and the inside area in anaerobic state
will adhere denitrifying bacteria. Therefore, ammonia nitrogen is nitrified
in the surface by the nitrifying bacteria will become nitrate, decomposed
from nitrate to nitrogen and water by the denitrifying bacteria on the
inside, nitrogen is then diffused into the atmosphere.
In the CarbonFiber biofilm, nitrifying bacteria on aerobic conditions, the presence of denitrifying bacteria of anaerobic conditions, nitrogen decomposition reaction is promptly carried out.
In the same way, by using the CarbonFiber water purification material, in water purification of rivers and lakes, nitrogen removal, such as ammonia nitrogen and nitrate in the water is promptly carried out, along with the results of high nitrogen removal effect. Moreover, greenhouse gas generation of dinitrogen monoxide will be suppressed.
|Aerobic and Anaerobic microorganisms to be fixed on CarbonFiber
|Accumulation of nitrogen oxide (NO3) in activated sludge
| Decomposition removal of nitrogen component by CarbonFiber
|Comparison of nitrogen reductions when CarbonFiber is used
|Comparison of greenhouse gas emissions when CarbonFiber is used
Souce：Mitigation of nitrous oxide (N2O) emission from swine wastewater
treatment in an aerobic bioreactor packed with carbon fibers, Takahiro
YAMASHITA, Ryoko YAMAMOTO-IKEMOTO, Hiroshi YOKOYAMA, Hirofumi KAWAHARA,
Akifumi OGINO, Takashi OSADA, Animal Science Journal, In Press, 2015