Effect of Forming Process and Particle Size on Properties of Porous Silicon Carbide Ceramic Candle Filters

성형공정(成形工程)과 원료입도(原料粒度)가 다공성(多孔性) 탄화규소(炭火硅素) 세라믹 캔들 필터 특성(特性)에 미치는 영향(影響)

  • Han, In-Sub (Reaction and Separation Materials Research Center, Korea Institute of Energy Research) ;
  • Seo, Doo-Won (Reaction and Separation Materials Research Center, Korea Institute of Energy Research) ;
  • Hong, Ki-Seog (Reaction and Separation Materials Research Center, Korea Institute of Energy Research) ;
  • Woo, Sang-Kuk (Reaction and Separation Materials Research Center, Korea Institute of Energy Research)
  • 한인섭 (한국에너지기술연구원 반응분리소재연구센터) ;
  • 서두원 (한국에너지기술연구원 반응분리소재연구센터) ;
  • 홍기석 (한국에너지기술연구원 반응분리소재연구센터) ;
  • 우상국 (한국에너지기술연구원 반응분리소재연구센터)
  • Received : 2010.08.04
  • Accepted : 2010.10.01
  • Published : 2010.10.30

Abstract

To fabricate porous SiC candle filter for filtration facility of the IGCC system, the candle type filter preforms were fabricated by ramming and vacuum extrusion process. A commercially available ${\alpha}$-SiC powders with various particle size were used as starting raw materials, and $44\;{\mu}m$ mullite, $CaCO_3$ powder were used as non-clay based inorganic sintering additive. The candle typed preforms by ramming process and vacuum extrusion were sintered at $1400^{\circ}C$ for 2h in air atmosphere. The effect of forming method and particle size of filter matrix on porosity, density, strength (flexural and compressive strength) and microstructure of the sintered porous SiC candle tilters were investigated. The sintered porous SiC filters which were fabricated by ramming process have more higher density and strength than extruded filter in same particle size of the matrix, and its maximum density and 3-point bending strength were $2.00\;g/cm^3$ and 45 MPa, respectively. Also, corrosion test of the sintered candle filter specimens by different forming method was performed at $600^{\circ}C$ for 2400h using IGCC syngas atmosphere for estimation of long-term reliability of the candle filter matrix.

석탄가스화 복합발전 시스템의 집진설비용 다공성 탄화수소 캔들 필터 제조를 위해 래밍성형과 진공 압출성형 공정에 외해 캔들필터 성형체를 제조하였다. 다양한 입도를 갖는 탄화규소 분말을 출발원료로 하였으며, 비점토계 무기 소결조제로 뮬라이트와 칼슘 카보네이트 분말을 사용하였다. 래밍성형과 진공 압출성형에 의한 캔들 필터 성형체들은 대기 분위기 $1400^{\circ}C$에서 2시간 소성하여 제조하였다. 캔들 필터 성형공정과 출발원료 입도가 소결된 다공성 캔들 필터 지지층의 기공율, 밀도, 강도 (굽힘강도, 압축강도)와 미세구조에 미치는 영향을 조사하였다. 래밍성형 공정에 외한 제조원 다공성 탄화규소 캔들 필터 소결체가 압출성형된 필터에 비해 높은 밀도 및 강도를 나타내고 있었으며, 그 최고 값은 각각 $2.0\;g/cm^3$과 45 MPa이었다. 한편 캔들 필터 지지층의 장기 내식성 평가 예측을 위하여 소결된 시편에 대해 석탄가스화 복합발전 $600^{\circ}C$의 모사 합성가스 분위기에서 2400시간 부식실험을 수행하였다.

Keywords

References

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