Evaluation and Certification Strategies for Lead–Zinc …
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off-gas; forming a liquid metal phase, where, e.g., iron or lead acts as an efficient
collector for various minor metals. In combination with mineral processing steps,
where a separation of metal-containing fractions could be realized prior or subsequent
to a metallurgical step, the targeted multi-metal recovery can be realized.
For hydrometallurgical concepts, the dissolution of a larger number of elements
followed by a selective precipitation, again combined with mineral processing,
would offer a multi-metal recycling. However, also a combination of hydro- and
pyrometallurgy could lead to appropriate solutions [6].
Facing the situation that for some by-products recycling concepts do not exist and
for those which are already partly recycled but with the majority recovering only one
metal, this approach must be regarded as one of the essential novelties.
Economic Considerations
Within the investigations, also a model for economic verification was established
and different dumps worldwide have been investigated. With this evaluation, high
promising dump sites as well as residues of poor quality have been detected.
Economics were done for different materials and metal prices. As already mentioned above, gold and silver contribute in a very important way to the overall revenues. However, the key message is that a multi-metal recovery is essential for the
economic stability of a recycling process and allows a higher flexibility regarding
varying metal prices.
Summary
By-products from metallurgical industry can play an important role as secondary
resource for different metals in the future. Important for the successful utilization is
a detailed evaluation and assessment of the materials, offering interested parties a
reliable information tool similar to already existing guidelines for primary resources.
Important steps to such an assessment concept are an advanced characterization of
the by-products combined with sophisticated processing concepts which in certain
cases might be already available but might be also subjected to new developments.
Especially, the idea of recovering more than only one metal from described byproducts would allow an economic and ecologic utilization of such wastes that will
play an important strategy for the future.
317
off-gas; forming a liquid metal phase, where, e.g., iron or lead acts as an efficient
collector for various minor metals. In combination with mineral processing steps,
where a separation of metal-containing fractions could be realized prior or subsequent
to a metallurgical step, the targeted multi-metal recovery can be realized.
For hydrometallurgical concepts, the dissolution of a larger number of elements
followed by a selective precipitation, again combined with mineral processing,
would offer a multi-metal recycling. However, also a combination of hydro- and
pyrometallurgy could lead to appropriate solutions [6].
Facing the situation that for some by-products recycling concepts do not exist and
for those which are already partly recycled but with the majority recovering only one
metal, this approach must be regarded as one of the essential novelties.
Economic Considerations
Within the investigations, also a model for economic verification was established
and different dumps worldwide have been investigated. With this evaluation, high
promising dump sites as well as residues of poor quality have been detected.
Economics were done for different materials and metal prices. As already mentioned above, gold and silver contribute in a very important way to the overall revenues. However, the key message is that a multi-metal recovery is essential for the
economic stability of a recycling process and allows a higher flexibility regarding
varying metal prices.
Summary
By-products from metallurgical industry can play an important role as secondary
resource for different metals in the future. Important for the successful utilization is
a detailed evaluation and assessment of the materials, offering interested parties a
reliable information tool similar to already existing guidelines for primary resources.
Important steps to such an assessment concept are an advanced characterization of
the by-products combined with sophisticated processing concepts which in certain
cases might be already available but might be also subjected to new developments.
Especially, the idea of recovering more than only one metal from described byproducts would allow an economic and ecologic utilization of such wastes that will
play an important strategy for the future.