Abstract
Properties of coke which was carbonized at lower temperatures than in the conventional process were examined experimentally, and the possibility of its use in a blast furnace was discussed.
The following results were obtained:
(1) When coke was carbonized under the conditions of final coke temperature higher than 800°C and higher heating rate, the same level of coke strength as that of conventional coke was obtained.
(2) The heating rate in the coal bed between 400°C and 500°C and the bulk density of charged coal controlled the pore structure, and were also important factors in determining coke qualities.
(3) It was noticed that the coke qualities might be improved by heat treatment in a blast furnace before the occurrence of coke degradation by solution-loss reaction.
(4) In order to obtain a higher heating rate in the coal bed, it was required that the chamber wall was constructed by the materials with high thermal-conductivity or that the thickness of chamber wall became thinner.
