Patent ID: 8052949
Filing Date: 2011-11-08
Classification: C01B,G01N,Y10T

Abstract:
1. A method of generating and maintaining sulfur trioxide gas, the method comprising: receiving a known concentration of sulfur dioxide gas; receiving an oxidizing agent gas; exposing the known concentration of sulfur dioxide gas and the oxidizing agent gas to a catalyst, the catalyst being heated, to react the known concentration of sulfur dioxide gas and the oxidizing agent gas into a known concentration of sulfur trioxide gas; maintaining the known concentration of sulfur trioxide gas in a gaseous state; wherein maintaining the known concentration of sulfur trioxide gas in the gaseous state includes maintaining the sulfur trioxide gas above a conversion point temperature of sulfuric acid; passing a portion of the sulfur trioxide gas, having a known concentration of sulfur trioxide gas, through a sulfur trioxide detection device, the sulfur trioxide detection device being a device that measures a concentration of sulfur trioxide; wherein receiving the known concentration of sulfur dioxide gas includes pre-heating the sulfur dioxide gas before exposing the sulfur dioxide gas to the catalyst; wherein exposing the known concentration of sulfur dioxide gas and the oxidizing agent gas to a catalyst includes heating the catalyst to a temperature between 225 degrees Celsius and 600 degrees Celsius; performing the step of reacting the known concentration of sulfur dioxide gas and the oxidizing agent gas into the known concentration of sulfur trioxide gas, and the step of maintaining the known concentration of sulfur trioxide gas in the gaseous state, within a sulfur trioxide gas generation system that supplies sulfur trioxide gas as a calibration gas to a combustion gas probe that measures exhaust gases; and heating the catalyst to above about 550 degrees Celsius to restore a degraded condition of the catalyst, the degraded condition causing reduced efficiency of converting the sulfur dioxide into the sulfur trioxide.