Bacillus SBR공정을 이용한 폐수처리

Abstract

Bacillus sp. have unique characteristic which forms spore in bad envirment. About bad environment, it could be too high or low pH and DO, temperature, radioactivity atc. When it becomes spore, this could mean removement for organic matter and nitrogen and phosphorus. And about SBR, it means Sequencing Batch Reactor. It changed spatial concept for temporal concept of established wastewater treatment system. It is possible to apply a wastewater process structure without considerable change. This experiment was conducted with lab-scale reactor. To remove nitrogen and phosphorous more efficiently, the computer program which was connected with DO meter in batch reactor controlled DO by on-off control. In the beginning, the computer program controlled DO as 0mg/L for 45minute. After that, 2mg/L for 75minutes and 0.5mg/L for 60minutes. This was 1cycle for the reactor. HRT was 12hours. So those 8cycle were repeated for 1day. About the influent, there were 3 mode so we can variate loading rate for the reactor. Mode 1 was 500mgCOD/L and 15mgTN and 2.5mgTP/L by diluting milk. And Mode 2 had a 50% enhanced loading rate compared with Mode 1. And Mode 3 had a 100% enhanced loading rate. In the beginnig of the cycle for 15minutes, the influent(4L) was transmtted automatically by pump which is connected with timer. And every end of 1cycle for 30minutes 4L of effluent was sucked by pump through membrane. MLSS in the reactor was kept as 5000mg/L. And pH was kept as 8.3 for dominating Bacillus sp. by Sodium Hydroxide. The result showed that removal efficiency of COD was 89~99% and BOD was 94~100% and TN was 76~91% and TP was 61~81%. This efficiency is better than reactor using normal microrganism SBR. Nitrification and denitrifycation was occurred. To check dominace in the reactor, we used the experiment in mocular biology. Microganisms in the reactor's 16S rDNA were investigated to check the dominace of Bacillus sp. As the result, we could know that we have succeed dominating Bacillus sp. in the reactor. wastewater treatment system. It is possible to apply a wastewater process structure without considerable change. This experiment was conducted with lab-scale reactor. To remove nitrogen and phosphorous more efficiently, the computer program which was connected with DO meter in batch reactor controlled DO by on-off control. In the beginning, the computer program controlled DO as 0mg/L for 45minute. After that, 2mg/L for 75minutes and 0.5mg/L for 60minutes. This was 1cycle for the reactor. HRT was 12hours. So those 8cycle were repeated for 1day. In the beginnig of the cycle for 15minutes, 500mgCOD/L and 15mgTN and 2.5mgTP/L's influent(4L) was transmtted automatically by pump which is connected with timer. And every end of 1cycle for 30minutes 4L of effluent was sucked by pump through membrane. MLSS in the reactor was kept as 5000mg/L. And pH was kept as 8.3 for dominating Bacillus sp. by Sodium Hydroxide. The result showed that removal efficiency of COD was 89~99% and BOD was 94~100% and TN was 76~91% and TP was 61~81%. This efficiency is better than reactor using normal microrganism SBR. Nitrification and denitrifycation was occurred. To check dominace in the reactor, we used the experiment in mocular biology. Microganisms in the reactor's 16S rDNA were investigated to check the dominace of Bacillus sp. As the result, we could know that we have succeed dominating Bacillus sp. in the reactor.