摘要：

The ratio of fuel to oxidant in a gas mixture to main burners in a furnace, wherein the fuel is of variable composition, is controlled to a predetermined level by burning a portion of the fuel in a control burner, adjusting the oxidant to obtain a ratio of fuel to oxidant near the stoichiometric ratio in the control burner and supplying the main burners with independent preset multiples of the fuel and oxidant flow in the control burner such that the predetermined ratio of fuel to oxidant is achieved.The stoichiometric ratio is determined by automatic searching for the peak value of a burning or burned fuel property which has a maximum value as a function of the fuel/oxidant ratio at or near the stoichiometric ratio. For example, the temperature of the burned fuel is a property which may be used to find the stoichiometric ratio.The method and apparatus for controlling burner stoichiometry may be used for improving burner efficiency and reducing pollution or it may be used to control the atmosphere of a furnace anywhere between oxidizing and reducing conditions.

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