Smelting of metallurgical waste materials containing iron compounds and toxic elements
CA 2065319 C · Owner: Baldock, Brian Ross · Inventors: Floyd, John Millice; Lightfoot, Brian William; Robilliard, Kenneth Roland
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Metallurgical waste materials, which are environmentally unacceptable for such applications as land fill, storage in open dumps and plastic lined ponds, because of the contamination of the ground water may be, processed to recover the useful and valuable materials (Zn Cd, Pb, Ag), and, bind the toxic elements (As Sb, Bi) as an environmentally acceptable slag. The waste material contains (a) at least one iron compound which may be, an iron or mixed oxide, (haematite goethite, ferrites and jarosites), (b) at least one heavy metal, (Zn, Pb, Cd), which is recoverable under strongly reducing conditions and volatilization and (c) at least one toxic element (As, Sb, Bi), which is separated from …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed August 23, 1990 and granted December 22, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 23, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 23, 2012.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.