Comparison of shredded tire chips and tire crumbs as packing media in trickling filters

Abstract

A five stage study was conducted using two trickling filters, one with shredded tire chips (12 to 50 mm) and the other with tire crumbs (1.5 to 6.5 mm) as packing media, and both landfill leachate and synthetically prepared leachate, to evaluate treatment performance. Due to increased surface area and sorption capacity, compared with other materials, a thick layer of biomass developed over the surface of tire chips and crumbs and sloughed off after approximately 21 days. Biochemical oxygen demand, chemical oxygen demand, and ammonia nitrogen removal were in the range of 81 to 96%, 76 to 90%, and 15 to 68%, respectively, under stable conditions. Organic removal and total dissolved solids reduction from the leachate were well correlated, with the exception of when biomass sloughing caused an increase in the organic content. The trickling filter with tire crumb media exhibited a more consistent organic removal throughout the experimental program. Tire chips, being readily available, could be a better alternative to crushed stone or gravel as a packing media in trickling filters. Tire crumbs appeared to be promising for small scale treatment systems. Copyright © 2007, CAWQ.