System for treating contaminated groundwater
CA 2062204 C · Owner: University Of Waterloo · Inventors: Blowes, David W.; Ptacek, Carol Jane
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A system for treating groundwater contaminated with acidity or other contaminants is disclosed. The system involves excavating a trench into the aquifer in the path of the contaminant plume and placing a body of active, material in the trench. The active material depends on the particular contaminant: organic carbon may be used when the contaminant is ferrous sulphate, or hexavalent uranium oxide, or dissolved nitrate; pyrite or elementaliron may be used when the contaminant is eg chromium oxide. The active material causes the contaminant to transform or break down by chemical reaction into harmless precipitates and substances.
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 3, 1992 and granted July 7, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 3, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 3, 2014.
- 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.