Abstract: Provided are a heat treatment apparatus for carbonaceous grains and a method therefor allowing drifts and internal clogging in a direct energizing furnace to not occur, allowing heat treatment of the carbonaceous grains to be continued uniformly at high temperatures for a prolonged period of time, and allowing productivity and workability to be improved. A conductive tubular structure 14 is electrically connected to an upper part of a lower electrode 13 in a manner of surrounding an upper electrode 12. The rate of change between the specific electrical resistivity of grains when grains are lightly filled and the specific electrical resistivity of grains when the grains are tap filled is defined (1-tap filling/lightly filling)×100, and the rate of change is equal to less than 70%.

Abstract: Provided are a heat treatment apparatus for carbonaceous grains and a method therefor allowing drifts and internal clogging in a direct energizing furnace to not occur, allowing heat treatment of the carbonaceous grains to be continued uniformly at high temperatures for a prolonged period of time, and allowing productivity and workability to be improved. A conductive tubular structure 14 is electrically connected to an upper part of a lower electrode 13 in a manner of surrounding an upper electrode 12. The rate of change between the specific electrical resistivity of grains when grains are lightly filled and the specific electrical resistivity of grains when the grains are tap filled is defined (1-tap filling/lightly filling)×100, and the rate of change is equal to less than 70%.