| 摘要 |
PURPOSE:To solve unstableness of furnace conditions, such as cooling of a furnace and overheating of the top of the furnace by a method wherein a tuyere which blows cold air into a specific part of a shaft of a vertical type thermal decomposion fusing furnace (a shaft furnace) is provided and a quanitity of a cold air blow is controlled so that a temperature of the top of the furnace falls within a range of a predetermined temperature. CONSTITUTION:An ordinary tuyere 4 and upper secondary tuyeres 5 are provided on a shaft furnace 1, cold air 7 is blown into the furnace 1 through the secondary tuyeres 5 by means of an air flow quantity control valve 6 and hot air 8 is blown into the furnace through the ordinary tuyere 4 as well. And a temperature detected with a top furnace temperature detector 9 is compared with a predetermined temperature generated by a predetermined temperature generator 10, based on this comparison a control signal is generated by a converter 11 for the control of the above control valve 6 and an air blow quantity from the secondary tuyeres 5 is controlled so that the top furnace temperature can attain the predetermined temperature. In this case a level of the secondary tuyeres 5 is set at a part of the shaft wherein a temperature in the vicinity of the furnace is higher than 700 deg.C. Because of this varying moisture content of a city garbage can be dried stably, and the desired end is attained. |
