On the design of nitrifying trickling filters for potable water treatment

A practical graphical method for the design of nitrifying trickling filters for potable water treatment is presented. The method allows the selection of the key design parameters (support media and filter dimensions) based on appropriate design curves. In the sequel, the possible advantages of water recirculation are examined theoretically and experimentally. Both theoretical and experimental results shown that an increase in ammonia bioconversion is expected for high or intermediate values of hydraulic loading and high values of inlet ammonia concentration, whereas at low hydraulic rates, recirculation has an adverse effect.