JPS5765520A - Automatic combustion controller for boiler - Google Patents

Abstract

PURPOSE:To prevent smoke generation in any condition and achieve a contribution to environmental protection by a method wherein the amount of chambustion air is regulated by a signal fed from a smoke color discrimination circuit which consists of a smoke color dinsitometer and an air-fuel ratio judging circuit. CONSTITUTION:A smoke color control circuit 100 is comprised of a smoke color detector 21, an adder-subtractor 22, a smoke color setter 23, a proportional integrator 24, a limiter 25, a while smoke generation limit air amount calculator 26, a comparator 27 and a signal inverter 28. At the time of black smoke generation, when a density output of the smoke color detector 21 becomes larger than the set point of the smoke color setter 23, the differnece signal is impressed on the an adder 29 to increase the air-fuel ratio, thereby preventing the smoke generation. On the other hand, at the time of white smoke generation, the signal inverter 28 is operated, and by operations reverse to those in the case of black generation, the air-fuel ratio is decreased to inhibit the white smoke generation.