The present invention presents a scrubber burner composed of a preheating spray ring that is formed with a porous material with certain thickness, and that preheats and sprays the fuel gas in the preheating combustion space formed inside, a preheating guide ring equipped with multiple preheating guide holes that wrap the outer circumference of the aforementioned preheating spray ring, and that penetrates from the outer circumference to the inner circumference, and a preheating burner module equipped with a housing that forms a ring shaped gas channel that is separated from the outer circumference of the aforementioned preheating guide ring and through which the aforementioned fuel gas flows.

Disclosed is a mixed combustion system fueled with ammonia, hydrogen and natural gas, which comprises a furnace chamber, a combustor, a heat exchanger, a mixer and a storage tank, the combustor and a conical combustion cavity are installed in the furnace chamber, the storage tank is provided with a first branch pipeline through a conveying pipe to be connected with the heat exchanger, the heat exchanger is connected with an inlet of the mixer, and an outlet of the mixer is connected with a fuel inlet of the combustor; and the conveying pipe is provided with a second branch pipeline connected with an ejector port of a first ejector, the first ejector is installed on a flue gas recirculating pipe connected with a furnace chamber flue gas exhaust pipeline, and the other end of the flue gas recirculating pipe is connected with an auxiliary fuel inlet of the combustor.