| 摘要 |
<p>PURPOSE:To decrease generation of excess sludge accompanying denitrification and to efficiently perform denitrification by equipping a fluidized bed type reaction tank in which granular sulfur is fluidized, an introduction means of raw water, the takeout means of treated water and gas and a circulation means for introducing a part of treated water taken out from the reaction tank thereinto. CONSTITUTION:In a fluidized bed type denitrification treating device, after activated sludge is added to the packed bed of sulfur granules 10 in accordance with necessity, raw water is introduced into a reaction tank 1 from an introduction pipe 2 of raw water to fluidize the sulfur granules 10. When operation is continued in the state, sulfur denitrification bacteria start to stick on the surfaces of the sulfur granules 10 and are furthermore propergated and good granules are formed. Denitrification reaction is performed with good efficiency, thereby. Denitrification treated water is drawn out from a takeout pipe 3 of treated water. A part thereof is circulated to the lower part of the reaction tank 1 from a pipeline 5 and the remainder is discharged to the outside of the system. Further a pH controller 6 is provided in the pipeline 5. Alkali. is added and pH is so regulated that it becomes the value suitable for denitrification.</p> |
