• 멤브레인
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• 제13권2호
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• pp.65-72
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• 2003

본 연구는 액상유기성 슬러지로부터 용존 유기물을 회수하기 위한 막결합형 발효 시스템의 여과특성의 검토에 초점을 두었다. $0.1 {\mu}m{\sim}5 {\mu}m$ 범위에서 6종류의 막공경을 대상으로 한 슬러지 발효액의 정밀여과 특성으로 막공경이 작을수록 전체저항이 큰 값을 나타내었고 케？층의 형성에 의한 저항이 전체저항의 68~88%를 차지하여 막투과유속의 저하는 주로 입자간의 물리화학적 상호작용에 의한 막표면에의 강한 입자침전에 기인함을 알 수 있었다. 발효액의 고형물 농도가 증가함에 따라 막투과유속은 감소하였으나 일정이상의 고형물 농도에서는 비례관계를 보이지 않았다. 막면유속이 증가할수록 그리고 5.0~6.0의 pH범위에서 높은 막투과유속이 얻어졌고 에너지 효율측면에서는 가능한 낮은 압력에서 여과하는 것이 유리한 것으로 나타났다. $0.1{\mu}m$과 $0.2{\mu}m$의 막공경에서는 100%의 미생물 제거율을 보였다 액상 유기성 슬러지로부터 용존 유기물을 효율적으로 회수하기 위한 최적 막공경은 제안된 기준의 관점에서 볼 때 $1{\mu}m$ 정도라 판단되어진다.

• 상하수도학회지
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• 제35권6호
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• pp.405-415
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• 2021

MMBR system has been suggested as a promising system to resolve harvesting problems induced from low settling efficiency of microalgae. And recently, a lot of research on reducing fouling at the MMBR system has investigated focused on EPS in many cases. EPS of microalgae mainly consists of polysaccharides and protein components, and is produced through photosynthesis and nitrogen-carbon metabolic pathways. Especially, P-EPS is one of major compounds which occur membrane fouling phenomenon, as its hydrophobic protein components cause floc formation and cake layer accumulation. And it is already known that almost every microalgae can metabolize P-EPS or Chl-a when nitrogen sources as a substrate is insufficient or exhausted situation. With the above backgrounds, uptake rates of P-EPS or Chl-a by Scenedesmus quadricauda according to the type of carbon source and nitrogen concentration were evaluated in order to verify correlation between carbon source vs P-EPS production, and indeed Scenedesmus quadricauda uses P-EPS or Chl-a when the amounts of nitrogen sourc es in the feed is not satisfied. As a result, it was shown that P-EPS and Chl-a production were increased proportional to nitrogen concentration under organic carbon condition. And especially, the amo unts of P-EPS and Chl-a in the cell were diminished with the nitrogen source becomes insufficient or exhausted. Because P-EPS accelerates fouling at the MMBR system, P-EPS degradation by Scenedesmus quadricauda in order to get nitrogen source may contribute to reducing fouling. About a affects of N-consumed Chl-a to the MMBR fouling, more survey is needed. On the contrary, considering the purpose of MMBR system of this study, i.e. harvesting useful high value microalgae efficiently feeding adequate industrial process wastewater, it seems like difficult to maintain satisfied metabolic activity and to harvest with high yield rate using nitrogen-poor MMBR feed.