METHOD FOR HEAT TREATMENT OF CERAMIC PRODUCTS (VERSIONS) Russian patent published in 1998 - IPC

FIELD: production of ceramic articles, in particular, bricks. SUBSTANCE: multi-chamber kiln comprises chambers intended to successively carry out in each of then drying, heating and roasting. Kiln also has recirculation system where blanks are charged into drying chamber followed by supplying the air into cooling chamber, and supplying heat carrier into roasting chamber. Off-gases formed in all chambers are collected and directed to gas recirculation system where they are removed into atmosphere, while finished products are discharged from cooling chamber. Off-gases from roasting and cooling chambers are directed to gas recirculation system to be mixed therein with off-gases coming from drying chamber to obtain the recirculate. The latter is divided into two streams. The first one which mass corresponds to mass of off-gases plus air admitted for cooling and inflowing into gas recirculation system is removed into atmosphere, while the second stream which mass is more than twice greater than that of the first stream, is recirculated back to drying, heating and cooling chambers. According to another version, off-gases coming from drying chamber are divided into two streams. The first stream which mass corresponds to that of off-gases plus air supplied for cooling and admitted into gas recirculation system is ejected into atmosphere, while the second stream is recycled back to gas recirculation system to be mixed therein with off-gases coming from roasting and cooling chambers. Finally second gas stream is directed to drying, heating and cooling chambers. EFFECT: higher efficiency. 2 cl, 3 dwg