| 摘要 |
<p>PURPOSE:To carry out the operation of highly concentrated sludge wihout using chemicals additive substantially by a method wherein a nitrogen containing water is subjected to a nitration treatment by activated sludge and thereafter is subjected to a denitrification treatment, the activated sludge separated from a treated water is used as a nitrogen source in a denitrification treatment. CONSTITUTION:A nitrogen containing water is supplied to a nitration tank 2 from a supply pipe 3 and subjected to a nitration treatment by the action of activated sludge. This treated water and the dehydrated activated sludge obtained from a forced dehydrating machine 7 are supplied to a denitrification tank and, while the nitration treated water is unaerobically stirred, subjected to a denitrification treatment using activated sludge as a carbon source. The denitrification treated water is supplied to a precipitate separation tank 10 to separate activated sludge and a part of this separated sludge is returned to a nitration tank 2 through a supply pipe 4 as well as the remaining sludge is supplied to a forced dehydration machine 7 such as a filter cloth type dehydrator, a centrifugal dehydrator or the like and a part of the dehydrated activated sludge is returned to a denitrification tank 6 and the remaining portion is supplied to a post-treating apparatus 11. The supernatant of a separating tank 10 is taken out into a water treating apparatus 12.</p> |
