Study on the efficiency and stability of nitrogen and phosphorus removal by Feammox
In order to explore the efficiency and stability of Fe(Ⅲ)reduction coupled with anaerobic ammonium oxidation(Feammox),the effects of iron oxidation type,sulfur limitation and low temperature(4 ℃)on nitrogen and phosphorus removal by Feammox were investigated,and the characteristics of sludge and microorganisms were analyzed.The results showed that the treatment group with the sulfate and ferrihydrite had better removal efficiency of nitrogen(above 84%)and phosphorus(above 98%),respectively.The products of ammonia oxidation in all experimental groups were mainly nitrite and nitrate,which were further removed by denitrification over time.Microbial community analysis showed that the abundance of ammonia oxidizing bacteria was higher in the sulfate and ferrihydrite,sulfate and magnetite groups,while denitrifying bacteria was dominate under sulfur limitation and low-temperature conditions.In conclusion,Feammox had a relatively stable removal efficiency of nitrogen and phosphorus.The ammonia oxidation efficiency was not significantly affected by sulfur limitation and magnetite with high crystallinity,but dropped dramatically at low temperature.
Feammoxwastewater treatmentnitrogen and phosphorus removalferrihydritemicrobial community