Lightweight aggregate from fly ash and sewage sludge
CA 2099985 C · Owner: Minergy Llc · Inventors: Heian, Glenn A.; Nechvatal, Timothy M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method is shown for producing a lightweight aggregate by treating fly ash and sewage sludge. The fly ash and sewage sludge are mixed together (30) and then agglomerated into pellets (12) with or without the use of a binder. The pellets may be coated (14) and then are dried (16). The dried pellets are introduced into a rotary kiln (18 or 38) in a direction that is co-current with the flow of fuel and air through the kiln. The pellets in the kiln will be indurated and will experience complete calcination as well as varying degrees of pyrolizing and sintering. The product of the kiln is a nodular material having a low density but with a hard and porous structure. The product of the kiln is …
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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 January 6, 1992 and granted December 2, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 6, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 6, 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.