Environmental impact of ore smelting: the African and European experience.

A study is presented of the stability of nonferrous metal smelting wastes in Europe and Africa and their effects on the adjacent soil environment. Slag, fly-ash and soil samples from smelting sites at Pribram, Czech Republic (primary and secondary lead), Tsumeb, Namibia (copper-lead-arsenic) and Kitwe-Nkana, Mufulira and Chambishi, Zambian Copperbelt (copper-cobalt) were studied using a range of analytical techniques as well as long-term and pH-static laboratory leaching experiments and soil mobility/bioavailability tests. For the Pribram site, the data from leaching experiments showed that higher amounts of lead are released from the primary than from the secondary lead slag and the latter material (slag from car-battery processing) is relatively stable, the released amounts of lead being low, even after long-term (12 y) interaction with water. For zinc, the concentrations released from primary lead slag were found to exceed the European Union regulatory limit for hazardous waste by about ten-fold and by more than 40-fold after 1 and 12 y of leaching, respectively. Leaching experiments carried out on slags from the Tsumeb site showed a high risk of arsenic and antimony release, with arsenates having a tendency to form efflorescence secondary minerals on the slag surfaces.
A study is presented of the stability of nonferrous metal smelting wastes in Europe and Africa and their effects on the adjacent soil environment. Slag, fly-ash and soil samples from smelting sites at Pribram, Czech Republic (primary and secondary lead), Tsumeb, Namibia (copper-lead-arsenic) and Kitwe-Nkana, Mufulira and Chambishi, Zambian Copperbelt (copper-cobalt) were studied using a range of analytical techniques as well as long-term and pH-static laboratory leaching experiments and soil mobility/bioavailability tests. For the Pribram site, the data from leaching experiments showed that higher amounts of lead are released from the primary than from the secondary lead slag and the latter material (slag from car-battery processing) is relatively stable, the released amounts of lead being low, even after long-term (12 y) interaction with water. For zinc, the concentrations released from primary lead slag were found to exceed the European Union regulatory limit for hazardous waste by about ten-fold and by more than 40-fold after 1 and 12 y of leaching, respectively. Leaching experiments carried out on slags from the Tsumeb site showed a high risk of arsenic and antimony release, with arsenates having a tendency to form efflorescence secondary minerals on the slag surfaces.