Experimental Pilot Scale Comparison Between Integrated Fixed Film Activated Sludge (IFAS) and Traditional Activated Sludge (AS) System for Municipal Wastewater Treatment

摘要

To ensure public health and to comply with regulation standards, the City of Beaumont Wastewater Treatment Plant (WWTP) is in the process of examining the options for upgrading its existing ammonia treatment system. The WWTP's BOD5 existing treatment system is a trickling filter system with a design capacity of 31.9 MGD of raw sewage. In this work, the efficiency of two alternative secondary treatment processes are evaluated, including the Integrated Fixed-film Activated Sludge (IFAS) and the Conventional Activated Sludge (AS).;This 6-month study utilized the primary clarifier effluent in parallel on-site batch experiments to compare AS and IFAS systems. The honey-comb K3 Bio Filter media with surface area of 427 m2m---3 was used in IFAS as moving bed for attached microorganism growth. The effect of HRT (aeration hydraulic retention time) was studied and then maintained at 6 hours for experimental trials. This study compared the results of the biomass growth rate and ammonia removal efficiency. The soluble COD, nitrate, ammonia, MLSS, MLVSS, pH, and DO obtained from both secondary treatment processes were monitored under similar conditions.;The biomass growth rate was 0.1091 +/- 0.0075 hour---1 for IFAS that was higher than AS for 0.0843 +/- 0.0615 hour ---1. Soluble COD removal loading was 283 gm---3day ---1 with 64% efficiency for IFAS and 273 gm ---3day---1 with 63% efficiency for AS. The average ammonia removal loading was 25.11 to 55.95 gm---3day ---1 with 96% efficiency for IFAS and 20.61 to 52.19 gm ---3day---1 with 82% for AS. The average effluent ammonia nitrogen concentration was 0.53 mgL---1 for IFAS and 2.12 mgL---1 for AS. The data also showed that the ammonia removal efficiency was higher and achieved sooner with IFAS as compared to AS.