PURPOSE: To deal with contingent change in fuel circumferences and to improve the use efficiency of fuels by setting the upper limit for the rate of supply of a main fuel, and burning dissimilar auxiliary fuels simultaneously with the main fuel when the main fuel attains the upper limit value according to furnace load.
CONSTITUTION: The in-furnace temp. T detected with a detector 1 for in-furnace temp. is transmitted to a controller 4 for in-furnace temp. In the controller 4 a set value TS of furnace temp. and an actually measured value of said in-furnace temp. are compared and operated to calculate a deviation Te of the furnace temp. Said deviation is converted to a signal FS for the set value of the total flow rate of fuels through PID operation. The signal FS is transmitted to limiters 5, 8 for flow rates of fuels. The limiter 5 is for a gaseous fuel and the limiter 8 for a liquid fuel. The respective limiters 5, 8 distribute the signal FS by the signal for setting the limited flow rate from a setter 11 for setting limiting flow rate and transmits a set value FGS for the flow rate of the gas eous fuel and a set value FOS for the flow rate of the liquid fuel to a limiter 6 for the flow rate of the gaseous fuel and a limiter 9 for the flow rate of the liquid fuel, respectively. The limiters 6, 9 control flow rate controlling valves 7, 10 so as to attain the flow rates of the set values.
TAKESHIMA RIKIO
SATOU KUNIAKI
MUTOU SHINICHIROU
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