Treatment of water
CA 2025433 C · Owner: Maree, Johannes P. · Inventors: Maree, Johannes P.; Augoustinos, Marios T.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention provides a process for the treatment of water containing dissolved sulphate, selenate tellurate and/or nitrate, anions, together with dissolved calcium cations. Water being treated is passed at a pH of 5,0 - 8,5 through an anaerobic biological water treatment stage wherein microorganisms utilize said anions and reduce their concentration in the water. The water from the anaerobic stage is then passed through a calcium carbonate precipitation stage where calcium carbonate is precipitated from the water at a pH of at least 7,0. Producer gas is fed through an anaerobic biological gas treatment stage wherein the proportion of hydrogen relative to carbon monoxide in the gas is …
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 February 20, 2001. 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.