| 摘要 |
<p>NITROGEN OXIDE CONVERSION PROCESS The present invention provides a novel process for treating a fluid stream carrying various components including nitrogen oxides, wherein the stream is subjected to oxidative reactions under gaseous and absorptive conditions to convert a portion of the nitrogen oxides to nitric acid and thereby simultaneously reduce the concentration of nitrogen oxides in the stream discharge. Basically, the novel process provided by the present invention for efficiently removing nitrogen oxides from a selected fluid stream and converting them to nitric acid, without the use of additional chemical elements, includes steps of: (a) further oxidizing a portion of the nitrogen oxides carried in the fluid stream; (b) removing liquid and gaseous effluents from the oxidizing means; (c) scrubbing the gaseous effluent removed from the oxidizing means with an aqueous solution of nitric acid; (d) separating the liquid and gaseous components of the stream removed from the scrubbing means; (e) bleaching the oxidizing and scrubbing liquid streams in contact with a countercurrent flow of gas; (f) passing the gas stream emitted from the bleaching means to the oxidizing means; and (g) withdrawing product nitric acid from the bleaching means. The process provided by the present invention can further provide a step of recycling a portion of the liquid effluent from the bleaching means to the scrubbing means to increase the concentration of nitric acid and can further include a catalytic oxidization process step wherein a silica gel and sodium silicate catalyst is used.</p> |
