Patent ID: 6282371
Filing Date: 2001-08-28
Classification: F01N,Y02T

Abstract:
A system for reacting a gas stream comprising:two coiled sidewalls, interspaced apart, comprising a first sidewall and a second sidewall, the first sidewall defining a concave surface and a convex surface, and the second sidewall defining another concave surface and another convex surface, each one of the coiled sidewalls having an interior portion and an exterior portion;a spiral inlet passage, formed by the coiled sidewalls, for enabling the gas stream to pass therethrough;a spiral outlet passage, formed by the coiled sidewalls, for enabling the gas stream to pass therethrough, the spiral outlet passage interspaced with the spiral inlet passage and in flow communication therewith;a matrix of porous inert media, disposed in at least a portion of at least one of the spiral inlet passage and the spiral outlet passage, the matrix capable of forming a thermal oxidation reaction zone therein; anda catalytic surface for reducing oxides of nitrogen in the gas stream, wherein the catalytic surface is disposed on the concave surface of the first sidewall and the convex surface of the second sidewall; and the convex surface of the first sidewall and the concave surface of the second sidewall lack the catalytic surface, whereby the catalytic surface directly communicates with the spiral inlet passage and lacks direct contact with the spiral outlet passage.