Apparatus and method for heating shaft furnaces with fuel gas

Claim 1

An improved shaft-furnace fuel gas burner of the type having a central supply line and distribution chamber for a first portion of combustion air; an annular supply line and annular distribution chamber for fuel gas surrounding the central air supply line; and, surrounding the annular fuel gas supply line, an outer supply line comprising two adjacent, concentric annular passageways one surrounding the other for a second portion of combustion air, the two passageways being in fluid communication at the top portions thereof whereby air may be passed upwardly through the innermost of the passageways to cool the fuel gas in the annular fuel gas supply line and then downwardly away from the top of the burner to a point of combustion air introduction near the bottom of the furnace, the improvement comprising: a second supply line and a second distribution chamber for fuel gas, and means for adjusting the supply of fuel to said second fuel supply line to control the combustion zone of the burner.

Claim 4

A method for heating vertical shaft furnaces with fuel gas comprising the steps of: introducing a combustion control portion of fuel gas into the furnace through a central conduit in a burner; introducing a combustion control portion of air into the furnace through an annular discharge chamber of the burner positioned below the point of introduction of the combustion control portion of fuel gas; introducing a main portion of fuel gas into the furnace through an annular fuel-discharge chamber of the burner positioned below the point of introduction of the combustion control portion of air; passing a main portion of air through the burner to cool the main portion of fuel gas before it enters the annular fuel-discharge chamber; conducting the main portion of air to a point adjacent the furnace bottom; and introducing the main portion of combustion air into the furnace adjacent the bottom thereof and below the burner whereby the main portion of air rises through the furnace and diffusely combines with fuel gas introduced into the furnace through the burner to heat the furnace.

Claim 5

A method for heating vertical shaft furnaces with fuel gas comprising the steps of: introducing a combustion control portion of fuel gas into the furnace through a central conduit in a burner; introducing a combustion control portion of air into the furnace through an annular discharge chamber of the burner positioned below the point of introduction of the combustion control portion of fuel gas; introducing a main portion of fuel gas into the furnace through an annular fuel-discharge chamber of the burner positioned below the point of introduction of the combustion control portion of air; passing a main portion of air through the burner to cool the main portion of fuel gas before it enters the annular fuel-discharge chamber; conducting the main portion of air to a point adjacent the furnace bottom; and introducing the main portion of combustion air into the furnace adjacent the bottom thereof and below the burner whereby the main portion of air rises through the furnace and diffusely combines with fuel gas introduced into the furnace through the burner to heat the furnace.