Method and device for igniting and operating burners when gasifying carbon-containing fuels

Abstract

With a method and a device for igniting and operating burners when gasifying a carbon-containing fuel using at least two gasification burners, start of the pressure gasification with short start times is made possible, at high pressures, without prior inertization of the gas space, while avoiding continuous fuel gas consumption in the pilot burner or ignition burner and also protecting stationary ignition burners against contamination by configuring one gasification burner as a start-up burner, which is ignited by at least one pilot burner using an electrical ignition device. A combustible gas mixture including a fuel gas and oxygen-containing gas is ignited by the pilot burner, in the start-up burner. After ignition of the start-up burner, at least one further gasification burner is ignited by this burner. The start-up burner is operated further as one of the gasification burners of the carbon-containing fuel via a change in medium.

1 . Method for ignition and for operation of burners in the gasification of a fuel that contains carbon, using at least two gasification burners, wherein
 one of the gasification burners is configured as a start-up burner,   for the ignition of which at least one pilot burner serves,   which is ignited by way of an electrical ignition device,   whereby a combustible gas mixture composed of a fuel gas and gas that contains oxygen is ignited by the pilot burner, in the start-up burner,   whereby after ignition of the start-up burner, at least one further gasification burner is ignited by this burner, and   the start-up burner is operated further as one of the gasification burners of the fuel that contains carbon, by means of a change in medium.   
     
     
         2 . Method according to  claim 1 , wherein
 after ignition of the start-up burner, the pilot burner has a gas mixture applied to it that contains CO 2  and/or steam and/or oxygen and participates in the gasification reactions, to prevent clogging.   
     
     
         3 . Method according to  claim 1 , wherein
 the pilot burner is first ignited at less than 50% of the power of the gasification burner being operated as a gas burner, and at an oxygen excess number of 0.8 to 1.2.   
     
     
         4 . Method according to  claim 1 , wherein
 in order to accelerate ignition of the mixture that contains oxygen in the gasifier, the pilot burner has a fuel excess/oxygen excess number<0.8 applied to it.   
     
     
         5 . Method according to  claim 1 , wherein
 the flame of the pilot burner is monitored and the ignition element of the pilot burner is shut off when the flame is recognized.   
     
     
         6 . Method according to  claim 1 , wherein
 an ionization flame monitor is used to monitor the flame of the pilot burner, whereby the ignition element is used as an electrode.   
     
     
         7 . Method according to  claim 5 , wherein
 an optical flame monitor is used, whereby the optical signal is passed to a detector by way of a lens and a light guide.   
     
     
         8 . Method according to  claim 5 , wherein
 the change in the electrical resistance of the ignition element is used to monitor the flame of the pilot burner.   
     
     
         9 . Device ( 1 ) for carrying out the method according to  claim 1 , wherein
 the pilot burner ( 2 ) is equipped with a centric nozzle head ( 3 ), which is surrounded by a burner pipe ( 7 ), which projects beyond the nozzle head ( 3 ) in the flow direction of the fuel gas, whereby at least one electrical ignition device ( 9 ) is provided within the burner pipe space ( 8 ), and a reduction in cross-section ( 11 ) of the burner pipe is provided behind that, in the flow direction.   
     
     
         10 . Device according to  claim 9 , wherein
 at least one flame monitoring element ( 13 ) is assigned to the burner pipe ( 7 ).   
     
     
         11 . Device according to  claim 9 , wherein
 the central nozzle head ( 6 ) is surrounded by a ring space that brings about the air or oxygen feed ( 5 ), in known manner, to feed in the fuel gas.   
     
     
         12 . Device according to  claim 9 , wherein
 the pilot burner ( 2 ) is positioned in the center of a gasification burner ( 15 ).