Afterburner for gas from gassification plant

Abstract

The present invention relates to an afterburner for gas from a gasification plant. The afterburner provides an optimal mixture of combustible gas and air, permitting an optimal reaction between the O2 in the air and the gas and creating a mixture ratio that enables the load on a burner to be regulated without altering the mixture ratio between air and gas. This offers the possibility of optimal combustion even during regulation of the burner, over the whole of the relevant regulating range. The result is extremely good combustion and reduced emissions of O2, CO and NOx.

1 . An afterburner for mixing combustible gas and air, which afterburner comprises a substantially circular mixing chamber with open ends, an inlet and an outlet, where the combustible gas is introduced into the mixing chamber at the inlet, and where air is added to the mixing chamber along the mixing chamber's circumference through one or more openings in the wall of the mixing chamber from an air supply chamber so that the combustible gas and the air are mixed in the mixing chamber, and where the mixture of the combustible gas and the air is discharged from the outlet in the mixing chamber, and where the air is introduced into the mixing chamber from the air supply chamber substantially tangentially to the interior of the mixing chamber and has a velocity generated by a fan in connection with the air supply chamber,
 wherein an overflow chamber is connected to the air supply chamber, which overflow chamber is provided with an outlet and a damper in connection with the outlet.   
     
     
         2 . An afterburner according to  claim 1 ,
 wherein a diameter D 1  at the mixing chamber's inlet and a diameter D 2  at the mixing chamber's outlet are different.   
     
     
         3 . An afterburner according to  claim 2 ,
 wherein the diameter D 1  at the mixing chamber's inlet is larger than the diameter D 2  at the mixing chamber's outlet.   
     
     
         4 . An afterburner according to  claim 1 ,
 wherein the air supply chamber surrounds the part of the mixing chamber where the air inlet openings in the mixing chamber's walls are provided.   
     
     
         5 . An afterburner according to  claim 1 ,
 wherein the overflow chamber surrounds the whole or parts of the mixing chamber and is connected to the air supply chamber.   
     
     
         6 . An afterburner according to  claim 1 ,
 wherein the damper's position can be varied with the result that the damper varies the airflow out of the overflow chamber.   
     
     
         7 . An afterburner according to  claim 1 ,
 wherein the connection between the air supply chamber and the overflow chamber is substantially at the openings between the air supply chamber and the mixing chamber.   
     
     
         8 . An afterburner according to  claim 1 ,
 wherein in the mixing chamber at the inlet to the mixing chamber, a cone is provided whose pointed end points towards the inlet of the mixing chamber, at which cone oil may be supplied.