Method for inhibiting high temperature corrosion of heat exchange surface of biomass boiler

A boiler combustion method using biomass as fuel, comprising:

• a first feeding step, supplying a first biomass fuel to a boiler, wherein the first biomass fuel is a mixture of kaolin and a second biomass fuel in the first feeding step, a chlorine content of biomass in the first biomass fuel is below 0.2% in the first feeding step, and a ratio of mass of kaolin in the first biomass fuel to a total mass of alkali metal and chlorine elements is from 2:5 to 6:5 in the first feeding step;
• a deposition step, performing combustion on the first biomass fuel during initial operation of the boiler, and forming an inert deposition layer on the a surface of a heat exchanger of the boiler;
• a second feeding step, supplying the second biomass fuel to the boiler;
• and
• a normal combustion step, performing combustion on the second biomass fuel;
• and
• a drying step, performing a drying process on the boiler after the first feeding step or the normal combustion step, wherein the drying step includes at least one of the following processing steps:
• an airtight processing step, performing airtight processing on a boiler door of the boiler to prevent the inert deposition layer from absorbing moisture in the air;
• a waterproof processing step, coating the heat exchanger with a waterproof material to prevent the inert deposition layer from absorbing moisture in the air;
• and
• a purging and drying processing step, supplying gas for drying to an inside of the boiler to purge and dry moisture adhered to the surface of the inert deposition layer.