Method of processing lead-bearing materials
CA 2129441 C · Owner: Shuklin, Aleksej Geradievich · Inventors: Shumsky, Viktor Aleksandrovich; Ljamina, Marija Alekseevna; Sannikov, Yuri Ivanovich
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of processing low grade lead-bearing materials where mostly simple and complex, sulphates and oxides of metals are present including higher iron oxides, such , as for example lead, residues, dusts of matte converting and other similar materials. The starting material is mixed, with fluxes, and powder sulphide and/or carboniferous material is inserted with a moisture content, of resulting charge from about 2 to about 16%. The charge is dried mixed with , oxidized recycle, dust, crushed carboniferous material and subjected to flash smelting in oxygen atmosphere. During smelting, the powder material reduces sulphate sulphur and higher iron oxides and, therefore a low melting …
Read the whole patent
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 October 12, 1993 and granted February 5, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 12, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 12, 2015.
- 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.