| 摘要 |
PROBLEM TO BE SOLVED: To shorten the time required for carbonization and to reduce the size of a carbonization furnace by introducing dehydrated cake of sewer sludge into an air current drying tube and drying this cake, then introducing the cake into a solid-liquid separator to separate the cake to powdery dry sludge and air current, then introducing the powdery dry sludge into the carbonization furnace and subjecting the sludge to the carbonization treatment by heat transfer heating, thereby forming powdery activated sludge coal. SOLUTION: A part of the powdery dry sludge is introduced into the carbonization furnace 32 and is subjected to the carbonization treatment by heat transfer heating, by which the powdery activated sludge coal is obtd. The resulted powdery activated sludge coal and the remaining part of the dry sludge are mixed to form an odorless dry sludge mixture. If, in such a case, 10 to 15 wt.% of the dry sludge obtd. by air current drying is subjected to the carbonization treatment and is mixed with the remaining dry sludge, and the smell of the dry sludge may be suppressed. The air current from a solid-gas separator 30 is heated in the carbonization furnace in common use as a hot stove and is then introduced into the air current drying tube 28 where this air current is preferably used as a heat source for air current drying. The resulted powdery carbonized sludge is usable as a deodorant for a bag deodorizing device 40. |
