The invention relates to a
combustion method and a
combustion device for a pulverized
coal hot air furnace. The method comprises the following steps of: simultaneously introducing gas and air into a
gas burner, igniting the gas and heating a pulverized
coal combustor to the temperature of more than 800 DEG C; feeding pulverized
coal with the
granularity of 180 meshes into the pulverized coal
combustor, igniting the pulverized coal and continuously combusting the pulverized coal in the pulverized coal
combustor; raising the temperature of an inner cavity of the pulverized coal combustor to be between 1,000 and 1,350 DEG C, injecting flames into a
combustion chamber through a
flame outlet of the pulverized coal combustor, and supplying the air through a secondary air inlet for full combustion; exhausting the burned fine particles which are carried by high-temperature hot air through an outlet of the
combustion chamber, making the air pass through an adjustable air inlet, and making
backflow flue gas pass through a
backflow flue gas inlet and rotate and rise in an air sleeve from the lower part of an outer sleeve; and recovering
waste heat, arranging a natural mixed air
pipe and introducing the air in the center of high-temperature
flue gas for mixing, and conveying the hot air to users through a hot air furnace outlet when the hot air is adjusted to the needed temperature. The invention has the characteristics that: the cost is reduced by utilizing low-price coal and
brown coal, the
combustion chamber and a mixed
air chamber are mixed into a whole, the pulverized coal is fully combusted, carbon residues are about 1 percent of ash, the
thermal efficiency is over 90 percent, and the like.