Study on the corrosion resistance of coating mixture to acid for the desulfurization system

탈황설비용 탄소강 코팅조성물의 내산성에 관한 연구

  • Kim, In-Ki (Department of Material Science & Engineering, Hanseo University) ;
  • Ryu, Jeong-Koon (Department of Chemical Engineering, Hanseo University)
  • 김인기 (한서대학교 신소재공학과) ;
  • 유정근 (한서대학교 화학공학과)
  • Published : 2006.12.31

Abstract

Coating mixtures of the resin B-H for the application to the desulfurization system of power plant were coated on carbon steels and cured at the temperature of $65^{\circ}C{\sim}80^{\circ}C$. After being contacted with 70wt% $H_2SO_4$ solution of $100^{\circ}C\;and\;120^{\circ}C$ for several hours, their composition, Vicker's hardness and microstructures by SEM were examined. Corrosion resistance of the coating mixtures to $H_2SO_4$ solution was related to the content of $SO_3$ in the coated specimens after corrosion test. The lower curing temperature and the shorter curing time the coated specimens went through, the higher corrosion resistance to acid they showed, but the more cracks were developed at higher temperature. It was realized that the corrosion resistance to sulfaric acid solution was increased on the condition of curing temperature above $65^{\circ}C$ and curing time above 12 hours at least.

발전소의 탈황설비에 적용하기 위한 B-H 코팅조성물을 탄소강에 코팅하여 $65^{\circ}C{\sim}80^{\circ}C$에서 경화시켰다. 이들 시편을 $100^{\circ}C$$120^{\circ}C$의 70 wt% $H_2SO_4$ 용액에 접촉시킨 후 코팅조성물의 조성, 비이커스 경도, SEM에 의한 미세구조 등을 분석하였다. 황산에 대한 내산성은 내산성 시험후 코팅 조성물의 $SO_3$양과 관련이 있었다. 경화온도가 높을수록, 경화시간이 짧을수록 내산성이 좋았으나 고온일 경우에는 균열이 더 많이 발생하여 내산성을 떨어뜨렸다 B-H 코팅 조성물의 고온 내산성을 향상시키기 위한 조건은 경화온도 $65^{\circ}C$이상, 경화시간 12시간 이상이었다.

Keywords

References

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