SIMULATION AND OPTIMIZATION OF TRICKLING FILTER

Abstract

Fixed-film biological processes are becoming more popular in waste water treatment because of low cost, smaller in size and simplicity in operation than submerged culture processes. The performande of a fixed-film biological reactor or trickling filter depends upon various parameters such as properties of biological film, influent substrate concen-tration, PH, Temperature and the volume of active biomass available for the stabilization of organic wastes. The volume of the active biomass depends upon the characteristics and size of packing material on which biomass is developed. In the present study an attempt has been made to simulate and optimize the trickling filter process parameters such as influent substrate loading, PH of the influent, recycle ratio, bed depth and influent volumetric flow rate for the performance of a trickling filter. Experiments have been carried out with lab scale trickling filter of size 6 cm in diameter and 166 cm in depth with 5 sampling points at a distance of 30 cm from each other. The quartz particles of the average size of 12.52 and 5 mm have been used as packing material. Because of nonavailability of industrial waste of uniform charac-teristics for these experiments, synthetic waste prepared iv by di ssolving a known-amount of molasses in tap water) was used. Result s indicate that depending upon waste charac-teri sitics, about 68 to 90% reduction in the influent COD of the waste water was achieved in 7 to 8 hrs. The influent COD, recycle ratio, influent flow rate and bed depth signifi-cantly influence the performance of the trickling filter.