Development of Bioreactors for Enrichment of Chemolithotrophic Methanogen and Methane Production

독립영양형 메탄생산세균의 농화 및 메탄생산 반응기의 개발

  • Na, Byung-Kwan (Department of Biological Engineering, Seokyeong University) ;
  • Hwang, Tae-Sik (Department of Biological Engineering, Seokyeong University) ;
  • Lee, Sung-Hun (Department of Biological Engineering, Seokyeong University) ;
  • Ju, Dong-Hun (Division of Water Environment and Remediation, KIST) ;
  • Sang, Byung-In (Division of Water Environment and Remediation, KIST) ;
  • Park, Doo-Hyun (Department of Biological Engineering, Seokyeong University)
  • 나병관 (서경대학교 이공대학 생물공학과) ;
  • 황태식 (서경대학교 이공대학 생물공학과) ;
  • 이성훈 (서경대학교 이공대학 생물공학과) ;
  • 주동훈 (한국과학기술원 유해물질연구센터) ;
  • 상병인 (한국과학기술원 유해물질연구센터) ;
  • 박두현 (서경대학교 이공대학 생물공학과)
  • Published : 2007.03.28

Abstract

A gas-circulating bioreactor was used for enrichment of autotrophic methanogens. Mixture of hydrogen and carbon dioxide (5:1) was used as a sole energy and carbon source. Anaerobic digestive sludge isolated from wastewater treatment system was inoculated into the gas-circulating bioreactor. The enrichment of two chemolithotrophic methanogens, Methanobacterium curvum and Methanobacterium oryzae was accomplished in the gas-circulating bioreactor. The enriched bacteria were cultivated in a bioreactor equipped with hollow-fiber hydrogen-supplying system (hollow-fiber bioreactor), and a hybrid-type bioreactor equipped with hollow-fiber hydrogen-supplying system and electrochemical redox control system. The methane productivity was maximally 30% (V/V) in the hollow-fiber bioreactors and 50% (V/V) in the hybrid-type bioreactor.

수소-이산화탄소(5:1) 혼합가스 순환장치를 장착한 반응기를 이용하여 독립영양형 메탄생산세균을 농화하였으며, 생산된 메탄의 농도는 10%미만이었다. 30일 이상 농화배양한 후 16S-rDNA 동질성을 이용하여 반응기에서 생장하고 있는 세균을 분석한 결과 수소를 단일 에너지 원으로 이용하는 Methanobacterium curvum와 Methanobacterium oryzae로 확인되었다. 농화된 세균을 hollow-fiber수소 공급장치를 장착한 반응기에 배양하여 메탄의 농도를 30%까지 향상하였다. 그러나 농화된 세균을 hollow-fiber 수소 공급장치와 미량의 수소를 생산하고 전기화학적 환원성 환경을 유도할 수 있는 장치를 장착한 복합형 반응기에 적용한 결과 메탄의 생산성은 50%가지 향상하였다. 이러한 결과는 독립영양형 메탄생산세균을 농화 또는 대량 배양하기 위해서 hollow-fiber 수소 공급장치와 전기화학적 환원력을 복합적으로 이용하는 것이 유리하다는 것을 보여주는 것이다.

Keywords

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