Abstract

Fellmongery, wet blue bovine, finished bovine, pelt tannage and chromium precipitation sludges and bovine wet blue shavings were assessed for chromium, chloride and sulphide leaching behaviour using 5000 ppm acetic acid buffered to pH 5 with sodium hydroxide, applied in consecutive bed volumes. The results were interpreted for a hypothetical co-disposal landfill site subject to either leachate treatment or groundwater contamination controls. In terms of chromium all of the sludges were considered satisfactory in the example situations. Chrome shavings were only acceptable for the leachate collection scenario and required pretreatment with 5% ^W/_W sodium carbonate to prevent groundwater contamination. Chloride levels were assessed as potentially unacceptable where groundwater contamination may occur whilst sulphide was not predicted to be of concern in either scenario. The work presents a design procedure for the landfill co-disposal of tannery wastes on a site by site basis.