Method of independently adjusting the fuel mixture composition and melting rate of multiburner shaft furnaces for melting metals
AssigneeNorddeutsche Affinerie Aktiengesellschaft
InventorsHeinrich Schliefer, Friedrich Wilhelm Warnecke
Life of this patent
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Abstract
A method of independently adjusting the fuel mixture composition and heating rate for a multiburner shaft furnace for the melting of metal, particularly copper and its alloys, fed in lump form to the shaft furnace, in which the burners are supplied with air and fuel gas and the heating rate is adjusted by controlling the pressure of one of the components of the fuel mixture (air or gas) in the manifold for supplying this component to a group of burners. The other fuel mixture component has its pressure controlled in its manifold by a single controller constituted by a pressure ratio controller.
Claims11
A method of independently adjusting a fuel-mixture composition and heating rate for a multiburner shaft furnace for melting metal wherein said shaft furnace comprises at least one more group of burners, respective first manifolds for feeding air to the burners of each of said groups, respective second manifolds for feeding a fuel gas to the burners of each of said groups, and respective control valves in each of said manifolds, said method comprising the steps of:
- controlling the heating rate by sensing the pressure in one of the manifolds of each of said groups of burners and operating the valve of the said one of said manifolds of each group in dependence upon the sensed pressure;
- and
- detecting the pressure ratio between the first and second manifolds of each of said groups of burners and controlling the valve of the other manifold of the first and second manifolds of each of said groups of burners in dependence upon the detected pressure ratio with a single pressure-ratio controller, thereby adjusting the fuel-mixture compositions for the burners of said groups.
A control system for a shaft furnace for the smelting of lumps of metal, comprising:
- a plurality of burners forming a first group and adapted to combust a mixture of air and a fuel gas for smelting metal in said furnace;
- a plurality of burners forming another group or groups adapted to combust a mixture of air and fuel gas to smelt metal in said furnace;
- respective first manifolds for feeding air to the burners of each of said groups;
- respective second manifolds for feeding fuel gas to the burners of each of said groups, each of said manifolds being provided with a respective control valve;
- and
- control means for imdependently adjusting the fuel mixture composition and heating rate in said shaft furnace, said control means including respective pressure-sensing means, responsive to pressure in each of said first manifolds and operatively connected to the control valves thereof for controlling the pressure of the air in said first manifolds for each burner group;
- a respective single pressure-ratio controller connected across to the first and second manifolds of each of said burner groups for producing an output representing the ratio of the pressures in the manifolds across with the pressure-ratio controller is connected;
- and
- means for applying the output of said pressure ratio controllers to the control valves of the respective second manifolds whereby the pressure ratio controller of each group of burners constitutes the sole controller for the fuel gas thereof.
Dependencies are inferred from the claim text.