DEVICE FOR THERMAL TREATMENT OF POWDER-LIKE MATERIAL Russian patent published in 1997 - IPC

FIELD: device for thermal treatment of powder-like materials; cement, chemical and other industries. SUBSTANCE: mixing chamber 16 is provided with additional burners 23 and 24 for burning fuel at air deficiency in lower portion (branch pipes 21) and at air excess in upper portion (branch pipes 22) in mixing chamber 16 and feeding part of starting material from cyclone of lower stage 7 to mixing chamber 16 through branch pipe 26 and device 29 for dividing starting material flow. Branch pipe 30 feeding the air from cooler 3 is located at one level with upper burners 24 and is brought radially to mixing chamber 16; it is provided with pinch 27 whose profile is made in form of Gauss curve inscribed by smooth or broken line 28. Device 29 for separating the starting material flow is also mounted in chute 12 of cyclone 6 before decarbonizer 14 for feeding the flow to two prechambers 15. EFFECT: increased degree of decarbonization of starting material before feeding it to rotary furnace and reduced discharge of nitric oxides into atmosphere. 5 cl, 5 dwg