Immobilisation of copper, chromium and arsenic on stabilised domestic refuse

The disposal of copper-chromium-arsenic, whether in solution or in combination with wood, has the potential to become a global problem. This chemical is commonly called CCA or Tanalith, and is classed as a waterborne wood preservative. Current global production of this class of chemicals is estimated at 90 000 tonnes annum-1 In South Africa (1988), the production of preservative treated wood approximates 430 000 m3annum-1 (UNEP, 1994). An experimental study to assess of the capacity of landfill biomass to adsorb (and retain) copper, chromium and arsenic waste chemicals has been carried out at laboratory and pilot scale. The work is motivated by the desire to explore the potential of domestic landfill sites to act as a final depositories for hazardous chemicals at minimal environmental risk. Copper is .present as the sulphate (copper (II)); chromium is present as dichromate (chromium (VI)); arsenic is present as the pentoxide (arsenic(V)). The laboratory scale investigation focused on the evaluation of kinetic rate constants (adsorption and desorption) and the evaluation of adsorption isotherms. At pilot-scale, the residence time distribution/deviation from ideal behaviour of the pilot-scale landfill columns was determined. Subsequently, the kinetic rate constants and the results from the residence time distribution studies were evaluated at pilot-scale. The final phase of the investigation was the application of the data obtained at laboratory and pilot-scale, to an assessment of full scale landfill practice.

Grantor dc:publisher.institution

Department of Chemical Engineering

Year dc:date.issued

1997

Author dc:creator

• Ballard, Richard Hugh

Advisor dc:contributor.advisor

• Petrie, Jim

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/9493

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/9493