Clean Technology (청정기술)

The Korean Society of Clean Technology (한국청정기술학회)
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A Study on NH3-SCR Vanadium-Based Catalysts according to Tungsten Content for Removing NOx Generated from Biogas Cogeneration

바이오가스 열병합 발전에서 발생하는 NOx 제거를 위한 텅스텐 함량에 따른 NH3-SCR 바나듐계 촉매 연구

  • Jung, Min Gie (Department of Environmental Energy Engineering, Graduate school of Kyonggi University) ;
  • Hong, Sung Chang (Department of Environmental Energy Engineering, Kyonggi University)
  • 정민기 (경기대학교 일반대학원 환경에너지공학과) ;
  • 홍성창 (경기대학교 환경에너지공학과)
  • Received : 2021.09.17
  • Accepted : 2021.11.01
  • Published : 2021.12.31
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Abstract

In this study, a vanadium catalyst study was conducted on the various characteristics of the exhaust gas in the Selective-Catalytic-Reduction (SCR) method in which nitrogen oxides emitted from cogeneration using biogas are removed by using ammonia as a reducing agent and a catalyst. V/W/TiO2, a commercial catalyst, was used as the catalyst in this study, and the effect was confirmed according to the tungsten content under various operating conditions. As a result of the NH3-SCR experiment, the denitrification performance was confirmed at 380 ~ 450 ℃ more than 95%, and durability to trace amounts of SO2 was confirmed through the SO2 durability experiment and TGA analysis. As a result of H2-TPR analysis, the higher the tungsten content, the better the redox properties. Accordingly, enhanced oxidizing properties were confirmed in the oxidation test for a trace amount of carbon monoxide emitted from the cogeneration. In NH3-DRIFTs analysis, it was confirmed that the higher the tungsten content, the higher both the Bronsted/Lewis acid sites and the better the thermal durability when tungsten is added to the catalyst. Based on the experiments under various operating conditions, it is considered that a catalyst with a high tungsten content is suitable to be applied to cogeneration using biogas.

본 연구에서는 바이오가스를 이용하는 열병합 발전에서 배출되는 질소산화물을 환원제인 암모니아와 촉매를 이용하여 제거하는 선택적촉매환원법(selective catalytic reduction, SCR)에 있어서 다양한 배가스 특성에 대한 바나듐 촉매 연구를 수행하였다. 연구에 사용한 촉매는 상용촉매인 V/W/TiO2를 사용하였으며 다양한 운전조건에서 텅스텐 함량에 따라 영향을 확인하였다. NH3-SCR 실험 결과 380 ~ 450 ℃에서 95% 이상의 탈질 성능을 확인하였으며 SO2 내구성 실험 및 TGA 분석을 통해 미량의 SO2에 대한 촉매의 내구성을 확인하였다. 또한 H2-TPR 분석결과 텅스텐 함량이 높을수록 우수한 산화·환원(redox) 특성을 확인할 수 있었다. 이에 따라 열병합 발전에서 배출되는 미량의 일산화탄소에 대한 산화실험을 수행하였으며 역시 우수한 일산화탄소의 산화력을 확인할 수 있었다. NH3-DRIFTs 분석에서는 텅스텐 함량이 높을수록 Bronsted/Lewis acid sites 모두 증가하였으며 텅스텐을 촉매에 첨가 시 우수한 열적 내구성을 갖는 것으로 확인되었다. 따라서 다양한 운전조건에 따른 실험 결과, 텅스텐 함량이 높은 촉매가 바이오가스를 이용하는 열병합 발전에 적용하기 바람직하다고 판단된다.

Keywords

Acknowledgement

본 연구는 2021학년도 경기대학교 대학원 연구원장학생 장학금 지원에 의하여 수행되었음.

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