Re-vegetation of tailings areas using recovered phosphates
CA 2010884 C · Owner: Sheridan, John Patrick · Inventors: Sheridan, John Patrick
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to re-vegetation o fmine teailings deposit areas. Generally mine tailings are highly acidic having a pH of 2.0 or, lower on a continuing basis. Fly ash from sanitary incinerators may have high amounts of phosphates of calcium, magnesium or aluminum. If the, fly ash is spread on the mine tailings deposit area and water is, introduced, complex chemical reactions arise which may result in the production of metal sulphides and phosphoric acid or super-phosphates of the metals. In any event, if metal sulphides are produced they are generally stable, and the phosphoric acid or metal superphosphates will release phosphates in a useable manner to any vegetation being grown in …
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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 February 26, 1990 and granted September 12, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 26, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 26, 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.