Mercury contaminated mud treatment
CA 2117754 C · Owner: Rockandel, Michael A. · Inventors: Twidwell, Larry G.; Rockandel, Michael A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to a hydrometallurgical process for the treatment of mercury contaminated muds. More particularly, this process pertains to a hydrometallurgical process for the treatment of Environmental Protection Agency designated K106 muds discharged from a mercury chlor-alkali plant. A hydrometallurgical process for the treatment of mercury containing solids comprising: (a) treating the solids in a first leach with acid and sodium hypochlorite to produce a leached product; (b) transferring the product from the first leach to a first washing thickener and thickening the leached product from the first leach; (c) transferring the underflow from the wash thickener to a second leach …
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 March 18, 1993 and granted May 4, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 18, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 18, 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.