기술 "화력발전 배출 온실가스, 메탄가스로 전환해 활용하자"

화력발전소에서 배출되는 이산화탄소(CO2)를 천연가스의 주성분인 메탄가스로 전환해 천연가스 발전 등에 활용할 수 있는 ‘이산화탄소 바이오메탄화 기술’ 개발이 본격 착수됐다.5일 한국전력(사장 조환익)은 LG히타치 워터솔루션과 함께 총 33억원의 예산을 투입해 오는 2019년까지 이산화탄소의 바이오메탄화를 위한 미생물 기술 및 공정 요소기술을 공동개발할 예정이라고 밝혔다. 연구개발에는 고등기술연구원, 한양대학교, 서울시립대 등이 참여할 예정이다.‘이산화탄소 바이오메탄화 기술’은 메탄을 생성하는 미생물을 통해 화력발전소에서 나오는 이산화탄소를 메탄가스로 전환하는 기술이다. 기존에 포집 후 지중이나 해저에 저장돼 버려지는 이산화탄소를 발전이나 난방 및 취사 등의 연료로 전환해 사용할 수 있는 고부가가치 기술로 석탄화력의 대안으로 떠오르고 있는 천연가스 발전에 사용할 수 있다. 이산화탄소 바이오메탄화 기술원리/ 자료제공=한국전력공사 또 신재생에너지의 잉여발전량을 이용해 메탄가스를 생산 후 저장했다가 필요할 때 저장된 메탄가스를 기존의 도시가스 배관을 통해 공급할 수 있는 P2G(Power to Gas) 기술로, 바람, 구름 등 날씨 변화에 따라 시시각각으로 변하는 풍력 및 태양광발전 등의 출력을 안정적으로 유지할 수 있어 신재생에너지의 에너지저장장치로 떠오르고 있다. 한전은 2019년까지 대량의 이산화탄소를 메탄가스로 전환하기에 적합한 메탄화 미생물의 선정과 대량 증식 및 메탄가스 생산플랜트 등 기술을 확보하고 오는 2022년까지 1MW급 실증설비를 통한 기술검증 후 2023년 이후 50MW급 상용설비를 개발해 보급할 예정이다. 이산화탄소 바이오메탄화 기술 개요/ 자료제공=한국전력공사 50MW급 상용설비를 이용해 하루 1000t의 이산화탄소를 메탄으로 전환 후 천연가스 발전용 연료로 활용하는 경우 연간 600억원의 연료비 대체 효과가 기대된다.한전 관계자는 “이산화탄소 바이오메탄화 기술개발은 지속적으로 증가하고 있는 깨끗한 환경에 대한 사회적 요구와 천연가스 발전의 경제성 확보를 모두 만족시키는 모델이 될 것”이며 “이를 통해 우리나라 온실가스 배출 감축 의무를 달성하고 전력산업의 지속적인 성장에 기여할 수 있을 것”으로 전망했다. 한편 국내 이산화탄소 포집·저장 및 재활용 기술개발 주요성과를 살펴보면 지난 2월 세계에서 5번째로 한국중부발전 보령화력본부에 설치된 이산화탄소 포집플랜트의 5000시간 장기 연속운전에 성공함으로써 포집분야의 이정표를 세운 것은 물론 국내 최대 규모의 이산화탄소 분리막 실증플랜트를 오는 8월 한국동서발전 당진화력본부에 설치될 예정이다.특히 한전은 2016년 이산화탄소를 중탄산나트륨 등 고부가 산업용 화합물로 변환해 생산하는 이산화탄소 자원화 원천기술을 확보했으며, 2018년까지 중탄산나트륨을 연간 700t 생산할 수 있는 파일럿플랜트를 구축할 계획이다.

원자력신문 2017.07.05

정책 The Future of Carbon Capture, Utilization, and Storage (CCUS): Status, Issues, Needs

This workshop brought together academic, government, and industry experts to review the status of carbon capture, utilization, and storage (CCUS) technologies, as well as the policy frameworks that would support further development. In both the electric power and industrial sectors, CCUS can play an important role in reducing global emissions of carbon dioxide (CO2). As of July 2016, a dozen countries are home to nearly forty large-scale CCUS projects in various stages of planning, construction, or operation. The current cost of employing CCUS technologies is high, however—$60 to $70 per metric ton of CO2 for power plants for capture, storage, and transport. Utilization of the produced CO2 can help defray costs, but investment in CCUS often would not occur without a supporting policy framework. The Trump administration has expressed interest in “clean coal”—and support for CCUS fits into this strategy.

Resources For Future 2017.05.24