CaSO4 기반 산소전달입자의 환원과 분해특성

RYU, HOJUNG;KIM, HANA;LEE, DONGHO;JIN, GYOUNGTAE;BAEK, JEOMIN
류호정;김하나;이동호;진경태;백점인

• Accepted : 2015.12.30
• Published : 2015.12.30
• 26 3

Abstract

As a candidate for cheap oxygen carrier, $CaSO_4$ based oxygen carriers have been developing. However, research on reaction characteristics and side reaction of $CaSO_4$ based oxygen carrier is very limited. There are many possible reactions for main components of syngas from coal. In this study, we prepared three $CaSO_4$ based oxygen carriers ($CaSO_4$-$Fe_2O_3$/bentonite, $CaSO_4$-$K_2CO_3$/bentonite, $CaSO_4$-CaO/bentonite) and performed reduction tests by hydrogen. Cyclic reduction-oxidation tests up to $5^{th}$ cycle are also conducted using hydrogen as fuel. Reduction reactivity of those $CaSO_4$ based oxygen carriers were compared with that of NiO based oxygen carrier (OCN703-1100). Real weight change fractions of $CaSO_4$ based oxygen carriers were higher than theoretical oxyen transfer capacity and reactivity of these particles decreased with the number of cycle increased. To check possible side reaction of $CaSO_4$ based oxygen carriers, $CaSO_4$ decomposition tests were carried out and $SO_2$ was detected even at $700^{\circ}C$. Consequently, we could conclude that $CaSO_4$ based oxygen carriers decompose and release $SO_2$ and this reaction lead reactivity decay of $CaSO_4$ based oxygen carries.

Keywords

CLC;Oxygen carrier particle;Reduction;Decompostion;$SO_2$

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Cited by

1. Conceptual Design and Feasibility Study on 0.5 MWth Pressurized Chemical Looping Combustor vol.27, pp.2, 2016, https://doi.org/10.7316/KHNES.2016.27.2.201

Acknowledgement

Supported by : 한국에너지기술평가원(KETEP)