Realization Of ANAMMOX In Anaerobic Rotating Biological Contactor And Study On Influence Of Different Factors

Nitrogen removal is the focus of the biological Wastewater treatment research. With the development of biology and cognition of the biological technology, some new methods and processes of nitrogen removal come into being. Among them ANAMMOX is the most concise and economic biological process for nitrogen removal, which is one of the focuses being researched. New bacteria-ANAMMOX bacteria can oxide ammonium to nitrogen directly using nitrite as electron acceptor. ANAMMOX bacteria are autotrophic bacteria. Because of their low biomass yield and the sensitivity to the environmental condition, it's very difficult to cultivate ANAMMOX bacteria. The start-up experiment was successfully carried out in anaerobic biological disc system. And the factor that influences the ammonium removal efficiency was researched, which indicates:1. Inoculated with anaerobic sludge from ASBR, the start-up experiment was successfully carried out in anaerobic rotating biological contactor after 142 days, which indicates that anaerobic biological disc is suitable for ANAMMOX bacteria to enrich. It is operated under the condition that the temperature is 40～41℃, HRT is 1.3d, pH is 8.25～8.5 and light is kept away. 98.15% ammonium removal efficiency and 99.56% nitrite removal efficiency was achieved when both ammonium and nitrite influent loading were 0.051kg·m^-3·d^-1.2. The color of the sludge has changed significantly from black to chocolate brown. It is found through microscope that the main bacteria in sludge is gram negative bacteria with rod and globose shape; and also some coccus was found gathered together on the surface of the granule sludge through scanning electron microscope.3. When it runs steadily, the ratio of nitrite and ammonium consumed is between 1.01 and 1.31, and the ratio of ammonium consumed and nitrate produced is between 0.14～0.20. The pH of effluent is a bit higher than influent because the process produces alkalinity.4. The experiment indicates that HRT=ld is a most suitable HRT both for enriching ANAMMOX bacteria and for high nitrogen removal efficiency. It's very difficult for ANAMMOX bacteria to enrich if the HRT is too short. The nitrogen removal efficiency achieved is higher under the condition that the ammonium concentration is high while the COD concentration is low than under the condition that the influent is inorganic, it is because the ANAMMOX bacteria and the denitrifying bacteria cooperate with together to removal nitrogen under the former condition.5. When the temperature of the reactor decreases for saving energy, filamentous bulking happens due to the excessive growth of the filamentous sulfur bacteria. After the temperature was changed back and the organics was removed from the influent, the filamentous bulking was prevented effectively.