| 摘要 |
<p>PROBLEM TO BE SOLVED: To form the treated water treated at a high degree by adding at least zeolite system ores to the sewage prior to a biological treatment and subjecting the sewage to a sepn. of solid from the liquid with a device for forming the powder obtd. by dehydrating sludge, then drying the sludge while adding quicklime thereto and kneading the sludge as a raw material for production of cement. SOLUTION: Treating agents 21 consisting of the fine powder of the zeolite ores or this fine powder and inorg. flocculating agent are added to the sewage 11 to adsorb and remove ammonia in the sewage 11 with the zeolite and, thereafter, the sewage is transferred to a final setting stage 1 where the sewage is subjected to settling and separating. The effluent 12 in the final settling stage 1 is then subjected to the biological treatment in an aeration stage 2 and the treated matter 13 contg. the excess sludge is transferred to the final settling stage 3. Next, the excess sludge 15 subjected to the settling and separating in this stage joins with the settled sludge 16 in the final setting stage 1. A dehydration arid 22 is added and mixed to and with the sludge in a sludge storage stage 4 and, thereafter, the sludge is subjected to a dehydration treatment in a dehydration treating stage 5. The quicklime 23 is added to the resultant dehydrated cake 17 and is dried to dry powder 18 in a mixing stage 6. This dry powder is used as the raw material for cement factories.</p> |
