Swirling-type furnace operating method and a swirling-type furnace

Abstract

The invention relates to heat engineering and can be used for designing and reconstructing furnaces for industrial boilers. More advantageously the inventive furnace can be used for burning coarsely dispersed broken combustibles, coal and schist. The invective swirling-type furnace operating method consists in returning the controllable amount of a coal-ash mixture from an ash catcher located behind a combustion to the internal surface thereof. Said swirling-type furnace comprises a combustion chamber provided with a sloping bottom which is formed by slops of lower parts of the walls thereof, a bottom-blowing device arranged under the sloping bottom mouth and an inclined burner which is used for supplying a fuel-air mixture and is fixed to the combustion chamber wall. The furnace is provided with the ash catcher located behind the combustion chamber and a recirculation ash channel, whose one end communicates with the ash catcher and the other with the combustion chamber internal space. The output openings of the channel are positioned between the sloping bottom mouth and the fuel supply burner or/and in a secondary combustion area, provided with an additional burner which is used for supplying the coal-ash mixture from the ash channel to the combustion chamber and is arranged therein. The ash catcher is selected according to a condition of catching particles whose size is greater than 0.5 mm. The ash channel can be provided with fly ash transporting and sorbent supply means.

1 . An operation method of a swirling-type furnace containing a combustion chamber, having a vortex zone and an afterburning zone, a bottom air inlet device, and a coal and ash mixture catcher for flue gas including feed of the fuel/air mixture and bottom air to the furnace, characterized in that the fuel/air mixture containing coarse crushed fuel is supplied to the vortex zone of the chamber, and a controlled amount of the coal/ash mixture caught from the flue gas is returned to a selected zone in the inner space of the combustion chamber. 
   
   
       2 . An operation method of a swirling-type furnace as in  claim 1 , characterized in that the selected zone in the inner space of the combustion chamber is selected to be the vortex zone. 
   
   
       3 . An operation method of a swirling-type furnace as in  claim 1 , characterized in that the selected zone in the inner space of the combustion chamber is selected to be the afterburning zone. 
   
   
       4 . A swirling-type furnace containing a combustion chamber with a dry-bottom hopper formed by the slopes of the bottom parts of the combustion chamber walls, a bottom air inlet device under the dry-bottom hopper mouth, and a downward-tilted burner to supply the fuel/air mixture, which is installed on the combustion chamber wall; the furnace has an ash collector behind the combustion chamber, an ash circulation duct with a dust transportation device; one end of the said channel connects to the said ash collector, and the other end connects to the combustion chamber inner space; the outlet of the said channel is in the area of the selected zone of the inner space of the combustion chamber. 
   
   
       5 . A swirling-type furnace as in  claim 4  characterized in that the coal/ash mixture consumption controller is installed in the ash duct. 
   
   
       6 . Swirling-type furnace as in  claim 4  characterized in that there is a sorbent input medium in the ash duct. 
   
   
       7 . A swirling-type furnace as in  claim 4  characterized in that the outlet of the circulation ash duct is placed between the dry-bottom hopper mouth and the fuel feed burner, and the ash collector is selected so as to catch particles that are larger than 0.5 mm. 
   
   
       8 . A swirling-type furnace as in  claim 4  characterized in that an extra burner is installed on the combustion chamber wall in the afterburning zone, the outlet of the circulation ash duct is combined with the said burner, and the ash collector is selected so as to catch particles that are larger than 0.5 mm.