Application of Ozone with Physical Wastewater Treatments to Recondition Poultry Process Waters

Abstract

Several wastewater treatments, including direct ozonation and a combination of ozonation with either slow sand filtration, dissolved air flotation, or diatomaceous earth (DE) filtration, were tested for their ability to recondition broiler process waters. The quality of broiler prechiller overflow water was significantly improved with all wastewater treatments examined, surpassing the USDA’s recycling requirements in nearly all trials. A combination of screening, DE filtration, and ozonation yielded the highest quality water. With this treatment, significant reductions in chemical oxygen demand, total solids, and the total microbial load including coliform bacteria and salmonellae of 87, 65, and 99.9%, respectively, were detected in the reconditioned prechiller water. Percentage of light transmission at 500 nm (%T) of treated water increased to 97% of tap water and compared favorably with %T of potable water. This same water treatment was tested on final carcass rinse and neck chiller overflow waters. The quality of these treated waters was also significantly improved. It was concluded that poultry process waters could be effectively reconditioned for recycling by screening, DE filtration, and ozonation. Furthermore, wastewater organic loads discharged to wastewater treatment facilities can be effectively reduced through these reconditioning practices.