Low-nox air heating swirl burner

A low NOx air heating swirl burner, comprising at least one burner unit, the burner unit comprising:

• a combustion air duct for providing combustion air and connected to a combustion fan through a duct;
• a fuel gas supply pipeline for supplying gaseous fuel;
• a combustion nozzle disposed at an air outlet of the combustion air duct and connected to the fuel gas supply pipeline;
• a fire protection baffle that covers the air outlet of the combustion air duct, and comprises a fin and a base plate for generating swirl combustion air;
• the combustion nozzle is mounted at a center of the base plate, and a gas outlet of the combustion nozzle is located on an air outlet side of the base plate;
• the base plate is provided with a plurality of elongated holes and air guide blades disposed obliquely on air outlet sides of the elongated holes;
• the plurality of elongated holes are distributed in a circumferential array by taking a center of the combustion nozzle as a circle center, and a length of each of the elongated holes is distributed in a radial direction or diagonally extended from an end near the circle center to an end away from the circle center;
• the fin is extended obliquely outward from an edge of the base plate in an outward expanding manner along an air outlet direction.