Pilot-scale Trickling Filter Nitrification at the Longmont WWTP

Nitrification rates in trickling filters can be affected by influent organic matter, filter length, and hydraulic loading rate. The effects of these parameters on nitrification rate were examined in pilot-scale trickling filters at the Longmont Wastewater Treatment Plant (LWWTP). Unstable nitrification rates were observed for the low hydraulic loading rates and short trickling filter lengths used at the LWWTP. Also, influent tBOD 5 ≥ 20 mg/l was found to significantly inhibit nitrification rates compared to influent tBOD 5 ≤ 10 mg/l. A trickling filter model for the LWWTP was calibrated based on these experiments.