| 摘要 |
PROBLEM TO BE SOLVED: To enable the easy treatment of NM3-containing waste water by disposing a stage for migrating NM3 into a gaseous phase from the NM3-containing waste water a stage for heating the generated NH3 containing gas and a stage for bringing heated NM3-containing gas into contact with a catalyst to crack NM3 to nitrogen and water. SOLUTION: When this method is applied to the treatment of the waste water discharged from night soil treatment facilities, the night soil waste water 20 is pretreated in an anaerobic digestion tank 1 and a non-dilution aeration tank 2 and is stored in a tank 3, following which the water is introduced via a pump 4 into a preheater 5, where the water is preheated up to about 100 deg.C. The night soil waste water 20 after the preheating is supplied to a post-stream stripping column 6 where the waste water rises in the column while coming into contact with vapor as a carrier gas 7 and releases NM3. The gas containing the released NM3 is diluted with dilute air 8 at need and is then introduced into a post stream catalyst column 9 where the gas comes into contact with the NM3 cracking catalyst 10 having a denitrification function. The NM3 is oxidized on the catalyst 10 and is cracked to N2 and H2O and thereafter, the gas is released into the atmosphere. |
