The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 20, 1991
Filed:
Jun. 04, 1990
Ebara Corporation, Tokyo, JP;
Abstract
A waste gas containing sulfur oxides (SO.sub.x) and/or nitrogen oxides (NO.sub.x) is purified by leading the waste gas to a radiation irradiation zone, adding ammonia (NH.sub.3) to the waste gas before, during or after the irradiation, collecting the resulting by-product (ammonium sulfate and/or ammonium nitrate) by means of a dust collector, and releasing the purified waste gas into the atmosphere. The amount of NH.sub.3 to be added is selected so as to be smaller than an amount calculated from target desulfurization and denitrification efficiencies so that it is possible to reduce the leakage of ammonia despite variations in the composition of the waste gas. Further, an alkaline substance exclusive of ammonia is added to the waste gas either at a position between the electrostatic precipitator and the bag filter or at the upstream side of a reactor outlet or both or within a dust collector or at the upstream side thereof so that the pH of the collected by-product is adjusted to 6 or more, preferably 7 or more, thereby suppressing the adverse effects of sulfamic acid impurities.