| 摘要 |
PURPOSE:To prevent the generation of hexavalent chromium and prolong the life of the titled incinerator which incinerates sludge while successively dropping the same from a drying zone to a burning zone and a cooling zone, by circulating an exhaust gas into the cooling zone to bring the zone in a low-oxygen content atmosphere. CONSTITUTION:As sludge is changed from a charging port 6, the drying load on a drying zone 2 increases, and the temperature lowers. In consequence, a regulating valve V1 is opened to circulate the exhaust gas into a cooling zone 4, thereby allowing the drying temperature 2 to be maintained at a predetermined temperature as well as a burning zone 3 to be maintained at a predetermined temperature. On the other hand, as the amount of the charged sludge decreases, the regulating valve V1 is gradually closed to the contrary. When the charging of the sludge stops, the regulating valve V1 is completely closed. In other words, the amount of the exhaust gas corresponding to the variation of the burning load is supplied to the cooling zone 4. In addition, the temperature of each of the drying zone 2 and the burning zone 3 is maintained constant at all times. Thus, the cooling zone 4 is constantly placed in a low-oxygen content atmosphere, so that the generation of hexavalent chromium is prevented. |
