Gas-solid contacting method
CA 2088484 C · Owner: Kjar, Anthony Rudland · Inventors: Wellwood, Grant Ashley; Still, Robert Francis; Goodes, Christopher Geoffrey
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A gas scrubbing process is disclosed whereby particulate material is contacted with a high velocity exhaust gas stream to reduce the resistance to mass transfer attributable to the diffusion boundary layer and provide higher mass transfer rates. The process is particularly suited to the scrubbing of gaseous fluorides from aluminium smelter pot exhaust gas with alumina. Additionally, it has been found that the fines fraction with a particle size of preferably less than 45 µm adsorbs or chemisorbs a disproportionate amount of contaminant trace metals from the exhaust gas stream. To avoid recycling these trace metals contained in the exhaust gas back to the smelter pot the fines fraction …
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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 2, 1991 and granted April 30, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 2, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 2, 2013.
- 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.