The technology for granulating coke breeze by centrifugal rolling type pelletizer, which is operated at a Froude number (Fr) 102 times more than an ordinary drum mixer, and the effect of granulated coke breeze on sintering operation, granulation of raw mix and quality of sinter were quantitatively studied by use of sinter pot and NAGOYA No.2 sinter plant.
The following results were obtained :
(1) In the granulation test of coke breeze, the centrifugal rolling type pelletizer can not only granulate fine coke breeze but also penetrate ultra fine coke particles into a coarser coke, while preventing the granulated particles from becoming excessively coarse.
(2) In the pot test and the sinter plant test, it was clarified that granulated coke breeze becomes the nucleus in quasi-particles of raw mix and then promotes the granulation of other raw materials in the sintering process of iron ores.
In addition, this new technology was confirmed to be able to decrease the NOχ emission by reducing the fine portion in coke breeze. The addition of quick lime reduces the NOχ emissions further. It was also clarified that the reducibility of sinter was improved.
