STEAM RECOVERY BOILER FOR BURNING SPENT LYES Russian patent published in 1999 - IPC

FIELD: cellulose production technology. SUBSTANCE: recovery boiler is used in cellulose production process for burning for example of wood chips or like material containing lignin. Recovery boiler has furnace. Base and walls of furnace incorporate multiplicity of tubes which are liquid-cooled. Base of furnace creates point of collecting inorganic substances in molten condition. Air and spent lye are introduced into furnace. Gases resulted from burning are moving upwards in boiler. Cross-sectional area of furnace at first lower level is larger than cross-sectional area of furnace at second level which is higher in upper part of furnace. Cross-sectional diameter at two levels is actually similar. Aforesaid embodiment of steam recovery boiler ensures lower speed of gases with resulted favorable separation and settling-down of molten droplets. Also obtained is uniform and quick through-flow of water. Safety of structure is enhanced. Manufacture can include use of automatic welding process. EFFECT: higher efficiency. 10 cl, 5 dwg