FURNACE, FURNACE OPERATION METHOD (EMBODIMENTS) Russian patent published in 2020 - IPC F27B1/02 

FIELD: furnaces and ovens.

SUBSTANCE: invention relates to kiln for calcination of carbonate raw material and method of obtaining >99 % of lime for hard burning or for production of >99 % of soft liquefied lime. Furnace includes at least two vertical shafts for lime production, each of which has respectively on its upper end supply for combustible material and at its lower end outlet hole for roasted material and which are connected by means of bypass channel, wherein above the bypass channel there is at least one main burner, respectively, and below the bypass channel a cooling gas supply is respectively provided, wherein at least one additional burner is located in shafts below bypass channel. Disclosed is a method for calcining carbonate material, comprising partial calcination of annealed material in a shaft operating in a firing mode in a main calcination zone located above the bypass channel, and additional heat treatment in the additional annealing zone located between the bypass channel and the corresponding additional burner, and in particular, is subjected to final calcination, and sintering can be provided as required.

EFFECT: possibility of producing lime with strong calcination and soft liquefied lime.

12 cl, 5 dwg