Study on the Removal Capacity of Ammoniacal Nitrogen by Biological Quartz Sand Filter

The removal capacity of ammoniacal nitrogen from the raw water in Chaohu lake was tested by the sand filter conventional water treatment technology.Results showed that a large number of microorganisms were propagated to consume ammoniacal nitrogen in quartz sand if there was no sterilizable process with chlorine before the filter technology by quartz sand.The average removal rate reached more than 67% when the concentration of ammoniacal nitrogen ranged from 0.1~2.5 mg/L in original water.The removal rate reached more than 70% and 80% as the concentration of ammoniacal nitrogen was respectively more than 0.5 mg/L and about 2.0 mg/L in original water.However,the average removal rate was about 46% when the concentration of ammoniacal nitrogen was less than 0.5 mg/L.The concentration of nitrite nitrogen was reduced by adding chlorine after the filter technology,and the removal rate attached more than 90%.