Pyrometric gas temperature measurement system

Claim 1

A system for remotely measuring the line averaged temperature of hot gases in a fired furnace comprising: (a) a black body in thermal contact with said gas, wherein said black body is fixed to an interior furnace side wall by means such that it is heated to within 100° C. below said temperature of said hot gases; (b) heating means surrounding said black body for adjusting physical temperature of said black body; (c) thermometer means in said black body for measuring the physical temperature of said black body; (d) a spectral pyrometer means in an opposite side wall viewing said black body through said gas wherein said spectral pyrometer operates at a wavelength where said gas has an emissivity within the range of 0.1 and 0.9; and (e) electronic means for comparing the physical temperature of said black body as measured by said thermometer with the radiation temperature measured by said spectral pyrometer to obtain a resultant signal that is used to control said heating means.

Claim 2

A system for remotely measuring the line averaged temperature of hot gases in a fired furnace comprising: (a) a black body in thermal contact with said gas, wherein said black body is fixed to an interior furnace side wall by means such that it is heated to within 100° C. below said temperature of said hot gases; (b) heating means surrounding said black body for adjusting physical temperature of said black body; (c) thermometer means in said black body for measuring the physical temperature of said black body; (d) a spectral pyrometer means in an opposite side wall viewing said black body through said gas wherein said spectral pyrometer operates at a wavelength where said gas has an emissivity within the range of 0.1 and 0.9; and (e) electronic means for comparing the physical temperature of said black body as measured by said thermometer with the radiation temperature measured by said spectral pyrometer to obtain a resultant signal that is used to control said heating means.

Claim 8

A method for remotely measuring the temperature of a hot gas in a fired furnace of unknown emissivity comprising: (a) fixing a heated black body to an interior side wall of said furnace in thermal contact with said gas, such that said black body is heated to within 100° C. below said temperature of said hot gases; (b) measuring the temperature of said black body through the gas with a spectral pyrometer in an opposite side wall, said spectral pyrometer having a selected operating wavelength such that the emissivity of said gas is between 0.1 and 0.9; (c) measuring the temperature of the black body independent of said pyrometer; (d) heating the black body until its temperature as measured with said spectral pyrometer is about the same as measured by said means independent of said pyrometer; and (e) comparing the physical temperature of said black body as measured with the radiation temperature measured by said spectral pyrometer to obtain a resultant signal that controls the heating of said black body.

Claim 9

A method for remotely measuring the temperature of a hot gas in a fired furnace of unknown emissivity comprising: (a) fixing a heated black body to an interior side wall of said furnace in thermal contact with said gas, such that said black body is heated to within 100° C. below said temperature of said hot gases; (b) measuring the temperature of said black body through the gas with a spectral pyrometer in an opposite side wall, said spectral pyrometer having a selected operating wavelength such that the emissivity of said gas is between 0.1 and 0.9; (c) measuring the temperature of the black body independent of said pyrometer; (d) heating the black body until its temperature as measured with said spectral pyrometer is about the same as measured by said means independent of said pyrometer; and (e) comparing the physical temperature of said black body as measured with the radiation temperature measured by said spectral pyrometer to obtain a resultant signal that controls the heating of said black body.