Recovery of CaO by Reductive Decomposition of Spent Gypsum in a CO-CO 2-N2 Atmosphere

Satoshi Okumura, Naoto Mihara, Ken Kamiya, Shoji Ozawa, Maurice S. Onyango, Yoshihiro Kojima, Hitoki Matsuda, Kyaw Kyaw, Yoshimi Goto, Tetsushi Iwashita

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

Reductive decomposition of spent CaSO4 was studied using a packed-bed reactor to regenerate an alternative CaO sorbent. The reactor was operated at various process conditions including an increasing CO concentration, CO/CO2 concentration ratio (0.067-1), and temperature (1123-1273 K). In all cases, N2 was used as a balancing gas. The regeneration of CaO from CASO4 was found to be most effective in the CO-CO 2-N2 atmosphere and strongly depended on the CO/ CO 2 concentration ratio. At 1273 K, an apparent conversion value of 0.91 for the decomposition of CASO4 to CaO was obtained in a 2 vol % CO and 30 vol % CO2 atmosphere. On the other hand, in a CO-N 2 atmosphere, CaS was predominantly produced. The SO2 absorption capacity of CaO regenerated from CASO4 was higher than that of limestone-calcined CaO. A larger pore diameter of the regenerated CaO was considered to be responsible for the higher SO2 absorptivity.

Original languageEnglish
Pages (from-to)6046-6052
Number of pages7
JournalIndustrial and Engineering Chemistry Research
Volume42
Issue number24
Publication statusPublished - 26-11-2003
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Chemical Engineering(all)
  • Industrial and Manufacturing Engineering

Fingerprint Dive into the research topics of 'Recovery of CaO by Reductive Decomposition of Spent Gypsum in a CO-CO <sub>2</sub>-N<sub>2</sub> Atmosphere'. Together they form a unique fingerprint.

  • Cite this

    Okumura, S., Mihara, N., Kamiya, K., Ozawa, S., Onyango, M. S., Kojima, Y., Matsuda, H., Kyaw, K., Goto, Y., & Iwashita, T. (2003). Recovery of CaO by Reductive Decomposition of Spent Gypsum in a CO-CO 2-N2 Atmosphere. Industrial and Engineering Chemistry Research, 42(24), 6046-6052.