Process for the treatment of waste water containing heavy metals
CA 2354388 C · Owner: Paques Bio Systems B.V. · Inventors: Buisman, Cees Jan Nico; Dijkman, Henk
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the treatment of waste water containing heavy metals is disclosed in which sulphur components and/or metals are biologically reduced to precipitate the metals as water-insoluble metal species which are , separated from the waste water. The biological reduction and the precipitation of the metal species are carried out in a moving sand bed in which sand , particles partly immobilise the bacteria and retain the precipitated metal species, treated waste water is separated from the precipitated metal species and the precipitated metal species are subsequently separated from the sand particles. Metals like selenium and uranium can be precipitated without sulphur components, …
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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 December 29, 1999 and granted November 22, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 29, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 29, 2021.
- 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.