Combustion apparatus with improved thermal efficiency

Abstract

A combustion apparatus includes a cylindrical combustion chamber surrounded by an inner wall. A cooling chamber comprises an intermediate wall spaced from the inner wall. Cooling water flows in and out lower and upper sides of the intermediate wall, to cool the inner wall by the cooling water that flows into a space formed between the inner and intermediate walls of the cooling chamber. A lateral combustion air supply chamber comprises an outer wall spaced from an outer side of the intermediate wall. Combustion air is supplied at an upper side of the outer wall to thereby make the air in a tangential direction with respect to the cylindrical outer wall turn and fall in a space formed between the intermediate wall and the outer wall, so that the combustion air is supplied to the combustion chamber via an opened lower portion of the lateral combustion air supply chamber.

1 . A combustion apparatus with improved thermal efficiency having a combustion vessel that receives an air supply from the outside to thus burn a fuel that is supplied from a fuel supply unit, the combustion apparatus comprising:
 a cylindrical combustion chamber that is surrounded by an inner wall of the combustion vessel to thus burn a fuel;   a cooling chamber that comprises an intermediate wall that is formed to be spaced apart from an outer side of the inner wall of the combustion vessel, in which a cooling water inlet and a cooling water outlet through which cooling water flows in and out, respectively, are formed at lower and upper sides of the intermediate wall, and that is formed at an outer circumference of the combustion chamber, to thereby cool the inner wall of the combustion chamber by the cooling water that flows into a space formed between the inner and intermediate walls of the cooling chamber through the cooling water inlet;   a lateral combustion air supply chamber that comprises an outer wall that is formed to be spaced apart from an outer side of the intermediate wall of the cooling chamber, in which a combustion air supply inlet through which air necessary for combustion is supplied from the outside is formed at an upper side of the outer wall, and that is formed at an outer circumference of the cooling chamber, to thereby make the air supplied through the combustion air supply inlet that is formed in a tangential direction with respect to the cylindrical outer wall turn and fall in a space formed between the intermediate wall of the cooling chamber and the outer wall of the lateral combustion air supply chamber, so that the combustion air is supplied to the combustion chamber via an opened lower portion of the lateral combustion air supply chamber.   
     
     
         2 . The combustion apparatus according to  claim 1 , further comprising:
 a boiler comprising a water tube to which the combustion gases that have been generated by burning the fuel in the combustion chamber are supplied to the boiler to thereby collect heat from the combustion gases, wherein the cooling water discharged from the cooling water outlet in the cooling chamber is connected with the water tube in the boiler via a connection tube so as to be used to collect heat from the combustion gases generated by the combustion vessel.   
     
     
         3 . The combustion apparatus according to  claim 2 , wherein a spirally shaped cooling water guide plate is provided in the cooling chamber so that the cooling water introduced via the cooling water inlet turns and rises up. 
     
     
         4 . The combustion apparatus according to  claim 3 , wherein the connection tube comprises first and second connection tubes, and a boiler feed water tank is provided between the first and second connection tubes, in which the cooling water discharged from the cooling water outlet in the cooling chamber flows into the water tube of the boiler via the boiler feed water tank. 
     
     
         5 . The combustion apparatus according to  claim 3 , wherein the fuel supply unit comprises:
 a fuel supply tube that is vertically placed on the lower portion of the combustion vessel and guides the fuels into the combustion chamber; and   a transfer screw that is formed in the fuel supply tube and having a screw shaft and screw blades that are formed on the screw shaft, in order to transfer the fuels into the combustion chamber, and   wherein the upper portion of the screw shaft is extended to the outside of the fuel supply tube, and is protrudingly formed in the combustion chamber, and a radial fuel supply element that is protrudingly formed perpendicularly from the axial direction of the screw shaft and thus is rotated together with the screw shaft, to thereby radially supply the fuels that are raised up through the fuel supply tube into the combustion chamber is formed at the upper portion of the protruded screw shaft.   
     
     
         6 . The combustion apparatus according to  claim 5 , wherein a fuel height control bracket that is protrudingly formed perpendicularly from the axial direction of the screw shaft and pushes the fuels outwards is installed at the end of the upper portion of the screw shaft that is protrudingly formed in the combustion chamber. 
     
     
         7 . The combustion apparatus according to  claim 6 , wherein the fuel supply unit that is installed at the lower portion of the combustion vessel further comprises a lower combustion air supply tube whose diameter is larger than that of the fuel supply tube through which fuel is supplied, and that is formed in the form of a concentric circle, to thereby supply combustion air from the lower portion of the combustion chamber to the bottom surface of the fuel. 
     
     
         8 . The combustion apparatus according to  claim 7 , wherein an upper end portion that is protrudingly formed from the fuel supply tube into the combustion chamber comprises: a diameter enlargement portion whose diameter gradually grows bigger upwards; and a slope guide portion that is bent downwards from the end portion of the diameter enlargement portion and is formed slantly downwards. 
     
     
         9 . The combustion apparatus according to  claim 8 , wherein an upper end portion that is protrudingly formed from the lower combustion air supply tube into the combustion chamber comprises an air feed diameter enlargement portion whose diameter gradually grows bigger upwards and that is positioned at the lower side of the diameter enlargement portion of the fuel supply tube, and wherein a number of air feed nozzles are formed in the diameter enlargement portion of the fuel supply tube so that the combustion air supplied from the lower combustion air supply tube is introduced into the combustion chamber. 
     
     
         10 . The combustion apparatus according to  claim 9 , wherein an upper end of the air feed diameter enlargement portion of the lower combustion air supply tube is closed by the slope guide portion of the fuel supply tube. 
     
     
         11 . The combustion apparatus according to  claim 9 , further comprising an upper combustion air supply chamber that is formed at the upper circumference of the combustion chamber and supplies combustion air to the upper portion of the combustion chamber, wherein the upper combustion air supply chamber comprises:
 a swirl flow supply chamber that comprises an upper intermediate wall that is formed so as to be spaced apart from an outer side of an upper inner wall that surrounds an upper inner side of the combustion chamber in which an air passage is formed at the upper end of the upper intermediate wall, and that supplies combustion air to the upper portion of the combustion chamber; and   a preheating chamber that comprises a cylindrical upper outer wall that is formed so as to be spaced apart from an outer side of the upper intermediate wall in which an upper air supply inlet through which combustion air is supplied from the outside is formed at the lower portion of the preheating chamber, in a tangential direction with respect to the upper outer wall, and wherein   the combustion air that is introduced into the preheating chamber through the upper air feed inlet of the upper outer wall turns, rises up and moves in the preheating chamber, and then moves from the upper portion of the swirl flow supply chamber to the lower portion thereof via the air passage formed at the upper end of the upper intermediate wall, to thus be supplied to the combustion chamber via a combustion air supply passage that is formed at the lower end of the upper intermediate wall.   
     
     
         12 . The combustion apparatus according to  claim 11 , wherein a rotary type fire grate on the upper surface of which a fuel that is supplied via the fuel supply tube is supplied is provided on the bottom of the combustion chamber, in which cross-section of both sides of the rotary type fire grate is formed in a V-shaped form.