Pre-treatment Characteristics of Night Soil by Microbubble

마이크로버블을 이용한 분뇨의 전처리 특성

  • Received : 2016.09.23
  • Accepted : 2016.11.03
  • Published : 2016.12.30


This study was conducted to investigate the effect of OH radicals on organic matter oxidation and suspended solids removal using microbubble as a pre-treatment technique to reduce the organic load of night soil in connection with sewage. The experiment was conducted for three months at HRT 4 hours using pressurized type microbubble generator. The mean SS removal efficiency was achieved 71%. The average removal efficiency of $TCOD_{Cr}$, TBOD, TN and TP were achieved for 51.5%, 47.9%, and 14.7% respectively, as scum and SS were removed by flotation separation. The removal efficiency of soluble organic matters were 25.0%, 17.1% for $SCOD_{Cr}$, SBOD by air microbubble supply. Soluble nitrogen and phosphorus were removed average of 11.9% and 7.4%, respectively. As s result, it was confirmed that soluble organic matters were removed by air microbubble supplied. Generated OH radicals when the microbubble was collapsed, can decompose the soluble organic matters. Therefore, The microbubble flotation process was installed at the front of night soil treatment process, it will contribute to the stable operation of the subsequent biological treatment facility by oxidation of the dissolved organic matters as well as removal of SS by flotation separation.


Microbubble;Night soil;Oxidation;OH radical;Organics removal


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