METHOD AND UNIT FOR CONTROLLING HEATING FURNACE

摘要

PROBLEM TO BE SOLVED: To maintain an optimum control state against load variation with small temperature variation against calorie variation of fuel gas. SOLUTION: The exit temperature Tout of heated fluid is measured and the ratio MV(n) of the mass flow rate of the fuel gas to the supply amount of the heated fluid needed to adjust the temperature of the heated fluid to set temperature is calculated from the measured temperature Tout and set temperature Tset . Further, the supply amount FL of the heated fluid supplied into the furnace 1 and the mass flow rate FW of the heated fluid are measured and a necessary fuel gas mass flow rate FWS=MVn×FL is calculated from the ratio MV(n) and the heated fluid supply amount FL. Then the flow rate of the fuel gas supplied into the furnace 1 is controlled according to the difference between the necessary fuel gas mass flow rate FWS and the fuel gas mass flow rate FW.