Method and apparatus for optical flame control of combustion burners

A method of monitoring operating conditions of a burner comprising the steps of:

• (a) monitoring flame radiation emission from a burner through a fiber optic attached to a spectrometer;
• (b) holding variables OC (optical collection system), OD (optical detector), O (oxidizer), F (burner fuel), B (burner characteristics), .rho. (process disturbances), and S (combustion stoichiometry) constant while varying P (burner power) to determine the emission intensity .GAMMA. as a function of power P by monitoring integrated OH emission intensity;
• (c) calculating constants A and B from a graph of emission intensity versus power having a characteristic equation .GAMMA.=AP+B;
• and
• (d) monitoring burner power P in real time using the equation ##EQU8##

A method of monitoring operating conditions of a burner comprising the steps of:

• (a) monitoring flame radiation emission of a burner through the refractory block by a fiber optic attached to a spectrometer;
• (b) holding variables OC (optical collection system), OD (optical detector), O (oxidizer), F (burner fuel), B (burner characteristics), and .rho. (process disturbances) constant while varying S (combustion stoichiometry) and P (burner power) to determine the power P as a function of the integrated emission intensity .GAMMA. of at least one of OH, CH, C2(A), and C2(B);
• and
• (c) monitoring the power P using the equation
• P=.rho..sub.a .GAMMA..sub.1.sup.2 +.rho..sub.b .GAMMA..sub.2.sup.2 +.rho..sub.c .GAMMA..sub.1 .GAMMA..sub.2 +.rho..sub.e .GAMMA..sub.1 .GAMMA..sub.4 +.rho..sub.f .GAMMA..sub.2 .GAMMA..sub.3 +.rho..sub.g .GAMMA..sub.2 .GAMMA..sub.4 +.rho..sub.h .GAMMA..sub.1 +.rho..sub.i .GAMMA..sub.2 +.rho..sub.j .GAMMA..sub.3 +.rho..sub.k .GAMMA..sub.4 +.rho..sub.1
• wherein the constants .rho.'s are determined from multivariable regression analysis, and wherein .GAMMA..sub.i, i=[1,4], are the integrated emission intensities of OH, CH, C2(A), and C2(B), respectively.

An integrated fuel burner and stoichiometry control apparatus comprising:

• (a) a fuel burner control apparatus including
• (i) means for viewing radiation emitted by flame from a burner to collect flame radiation intensity data as a function of time;
• (ii) means for optically transporting the viewed radiation emitted by said flame from said burner into an optical processor;
• (iii) an optical processor for selecting one or more specific spectral regions of viewed radiation and means for converting said one or more specific spectral regions into first electrical signals indicative of flame radiation intensity for those spectral regions over time;
• (iv) a signal processor for integrating flame radiation intensity for the specific spectral regions over time and generating second electrical signals;
• and
• (v) control means which accepts said second electrical signals from said signal processor and produces an output acceptable to a controller for controlling oxidant flow, fuel flow, or both oxidant flow and fuel flow;
• and
• (b) a burner refractory block, wherein said means for viewing the radiation comprises a hole in a position on the refractory block suitable for viewing said flame.

A process for controlling the inputs of oxidant or fuel into a burner, the method comprising the steps of:

• (a) selecting usable radiation wavelengths from one or more optical ports on the burner;
• (b) operating the burner over a range of combustion stoichiometry with inputs of oxidant, fuel, or both over a range of operating conditions;
• (c) measuring electric signals from the usable wavelengths;
• and
• (d) determining a mathematical function between the electrical signals and the inputs of oxidant, fuel, or both by modeling a relationship between said electrical signals and said inputs of oxidant, fuel, or both with a modeling method selected from the group consisting of statistical modeling, neural network modeling, and physical modeling.

A process for controlling a fuel burner comprising the steps of:

• monitoring burner flame radiation emission;
• determining integrated intensity values for the flame radiation emission;
• selecting specific integrated intensity values that vary with burner stoichiometry changes;
• and
• adjusting the stoichiometry of the burner mixture based on the integrated intensity value.