Electrostatic waste separation process
CA 2010187 C · Owner: Pittsburgh Mineral & Environmental Technology, Inc. · Inventors: Weyand, Thomas Edward; Gilbert, Stanley Rice
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An electrostatic waste separation process for abrasive blasting residues containing an abrasive media and a hazardous material such as lead-based paint. A preconditioning stage as well as a postconditioning stage is used in addition to the electrostatic separation step. Preferably the preconditioning stage consists of the following steps: (a) a size classification step; (b) a ferromagnetic separation step; and (c) a gravity separation step. The concentrated hazardous material separated by this process can then be packaged in a container which can be safely transported stored or, disposed of. The nonhazardous blasting media may be recycled and reused or disposed of as a nonhazardous material.
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 February 15, 1990 and granted May 3, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 15, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 15, 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.