Removal of wool wax, nonylphenol ethoxylates and pesticide residues from wool scour effluent

Abstract

The aqueous scouring of raw wool produces a highly polluting effluent that primarily contains emulsified wool wax, together with high levels of nonionic detergents and trace levels of various agricultural pesticides. The SIROLAN CF chemical flocculation process transferred over 95% of the wool wax and detergent and greater than 98% of the pesticide residues from the wastewater stream to a spadeable sludge that was used as a starting material to produce a high quality compost. During the composting process the nonionic detergents and organophosphorus pesticide residues were degraded to below detectable levels while the pyrethroid pesticides, cypermethrin and cyhalothrin, together with the organochlorine pesticide, lindane were degraded to below 15% of their initial levels.