Sieve screen deck and separation method
CA 2028020 C · Owner: Monarch N.L. · Inventors: Lees, Jeremy James; Dalzell, Andrew James; Pryor, Murray Howard
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the recovery of coal particles having a maximum dimension of less than 2 mm from coal tailings including the steps of forming a slurry (101) of tailings having a pulp density of from 10 to 30% by weight; feeding the slurry into a hydrocyclone (103) to produce an underflow second stream which contains the tailing particles over a predetermined size and some of the gangue particles smaller than that size and an overflow stream containing the coal particles smaller than the predetermined size and the balance of the gangue particles the hydrocyclone (103) being operated such that the underflow stream has a pulp density of from 40% to 60% by weight; adjusting the pulp density of …
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 September 19, 1990 and granted March 23, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 19, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 19, 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.