Influence of Ca-Based Sorbent Particle Size on the Occurrence of Solid-Solid Reactions during in-Situ Desulfurization of the Coal-Derived Gas

详细信息    查看全文

• 作者：Hassan Katalambula ; Maria Mercedes Escalló ; n ; and Shohei Takeda
• 刊名：Energy & Fuels
• 出版年：2001
• 出版时间：March 2001
• 年：2001
• 卷：15
• 期：2
• 页码：317 - 323
• 全文大小：433K
• 年卷期：v.15,no.2(March 2001)
• ISSN：1520-5029

文摘

The introduction of sorbents into the gasifier during in-situ desulfurization processes usingcalcium-based sorbents leads to the occurrence of some reactions, mainly between the calcium(Ca) in the sorbents and some minerals contained in the ash, especially iron (Fe). These reactions,which are between solid phases (solid-solid), affect the absorption ability of the sorbents. Theoccurrence of solid-solid reactions, however, depends on a number of factors. In this paper, theeffect of sorbent particle sizes on the occurrence of solid-solid reactions in desulfurizationprocesses has been investigated using a laboratory-scale fixed bed reactor. Mineral compositionsin the spent sorbent-ash mixture were analyzed by X-ray diffraction, and the elementaldistribution within individual particles was determined by the electron probe micro analysis(EPMA). Results show that the occurrence of solid-solid reactions increases with decreasingparticle size, which is accompanied with the reduction of the sulfur absorption ability of a sorbent.Increasing the iron concentration in the coal ash led to the occurrence of more solid-solidreactions, suggesting that in high-iron-content coals, the effects of solid-solid reactions may bemore serious. Despite the fact that iron is the major player in the occurrence of solid-solidreactions, other minerals present in the ash seem to play a catalytic role.