Oxidation of calcium sulfide in an advanced PFBC cycle -- Effect of O{sub 2} concentration and particle size on CaS oxidation

Conference · Wed Dec 31 04:00:00 EST 1997

OSTI ID:355839

Ninomiya, Y; Dong, Z B; Hashimoto, K; Sato, A ^[1]

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1. Chubu Univ., Kasugai, Aichi (Japan). Dept. of Industrial Chemistry

The oxidation reactivity of CaS samples obtained by sulfidation of limestone was investigated by using a thermal analyzer (TG-DTA). The experiments were conducted with different particle sizes of the sorbent samples from 0.2 to 0.88 mm at reaction temperatures of 900 to 1,350 C in atmospheres containing 1 to 21% of O{sub 2} in N{sub 2}. The complete conversion of CaS in the fine particles to CaO and CaSO{sub 4} was achieved at 930 C with the reaction time of about 400 minutes under 1% O{sub 2} condition. The apparent reaction rates of he CaS samples strongly depended on O{sub 2} concentration and particle size under low oxidizing conditions. On the other hand, the reaction scarcely happened with lower conversion below 1,050 C for higher O{sub 2} conditions, because the outside shell of the sample became covered with a CaSO{sub 4} product layer and the oxidation reaction ceased due to increasing intraparticle diffusion resistance to the reactant gas. Above 1,180 C, however, CaS in the sample was essentially converted to CaO and CaSO{sub 4} at all experimental conditions in this study.

• OSTI ID: 355839
• Report Number(s): CONF-9705116--; ISBN 0-7918-1557-9
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
CALCIUM SULFIDES
COAL
CONCENTRATION RATIO
FLUIDIZED-BED COMBUSTORS
LIMESTONE
OXIDATION
OXYGEN
PARTICLE SIZE
PRESSURIZATION
SORBENT INJECTION PROCESSES
SULFIDATION