作者：Yoshitaka SADATOMI, Koji IDE, Koji GODA and Mitsuo SUGAWARA

作者单位：

刊名：Journal of the Technical Association of Refractories, Japan

ISSN：

出版年：2014-03-01

卷：34

期：1

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止页：

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语种：英文

关键词：magnesia, castable, time-dependent change mechanism, carbonation, and hydration control

内容简介

Magnesia added to castable is easily hydrated, because it is exposed to super-heated steam in drying process and it sometimes even leads to collapse of the structure of installed lining. In addition, magnesia, as a raw material, is originally partially hydrated at the initial stage because it is exposed to moisture in the atmosphere while it is kept in storage. And this partial hydration of magnesia accelerates further hydration of magnesia in castable. Therefore, it is important to clarify the mechanism and to control the hydration result from time-dependent changes. In this paper, at first, influence of the time-dependent changes in raw material stage on hydration rate of magnesia in castable under super-heated steam was investigated. As a result, castable containing magnesia whose hydration exceeded threshold level accelerated the hydration rate of magnesia in castable, expanded and collapsed under super-heated steam. In contrast, castable containing preferentially carbonated magnesia didnt collapse under super-heated stream. And it became possible to control hydration by application of pre-carbonation treated magnesia on the surface.