FIELD: pulp-and-paper industry. SUBSTANCE: liquid 5A is introduced on given level 4 into furnace 1,2,3 wherein liquid 5A is first evaporated, then solid residue is pyrolysed and finally burned out. Remaining chemicals are collected on the furnace bottom. Off-gases 8 pass upward and leave furnace. A part of air to maintain burning, so called primary air (11), is entered on one or several levels 6 below level 4 of liquid inlet 5A. Another part of combustion air, secondary air (12), is entered on one or several levels 7 between level 4 of liquid inlet and primary air inlet 6. Secondary air 12 enters the furnace being forced to circulate in the plane perpendicular to longitudinal axis 13 of furnace so that entered liquid 5A is repelled outward in direction of furnace walls 2. EFFECT: eliminated so called "chimney effect" in furnace. 4 cl, 2 dwg
