Process for the reduction of the NO content in flue gas, in the heating of rich gas or verbund coke ovens and group of coke ovens to carry out the process

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Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.

Why it's free to use

• Filed November 8, 1989 and granted January 19, 1994. A European patent lasts at most 20 years from filing, so its term ended November 8, 2009.
• A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by May 8, 2015.
• We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.