Method of removing metallic impurities from sewage sludge
CA 1102456 A · Owner: Simon-Carves Limited · Inventors: Abson, James W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract:, A method of removing metallic impurities from sewage sludge wherein the sludge is first acidified in the presence of an oxidising agent and held to take metallic impurities into solution. The sludge is then treated with a flocculating agent and thickened by removing liquid prior to dilution with an aqueous liquid free from metallic impurities and wherein the sludge is finally dewatered by a mechanical method.
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
- Granted June 2, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 2, 1998.
- 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.