| 摘要 |
PURPOSE:To enable uniform calcination by a small amount of gaseous fuel, in a shaft type furnace of which the inner diameter becomes larger toward the lower part from the upper part thereof, by providing a preheating drying part, a mixed gas injecting part, a gas combustion part, a calcining part, a cooling part and a cooling air injecting part from the upper part of said furnace. CONSTITUTION:By using a shaft type furnace 1 of which the inner diameter becomes larger toward the lower part from the upper part thereof, a flame and a combustion gas from gas burners 8, 8' are flowed toward a negative pressure part position 6 to carry out the calcination of a material in the region from a position 5 to the position 6. In addition, a cooling air stream due to cooling air jet orifices 11, 11' at a position 7 is flowed toward the position 6 to carry out the cooling of the calcined material between the positions 6, 7. Moreover, the negative pressure part position 6 is formed by sucking the combustion gas and air by suction pipes 14, 14' and the mixed gas of the combustion gas and air is injected from injection pipes 9, 9'. On the other hand, a negative pressure part is formed by sucking a gas by discharge pipes 21, 21' and the drying and the preheating of the material supplied from the supply means 2 provided to the top part of the furnace is carried out while the calcined product is taken out by the taking out means 26 provided to the furnace bottom. |
