作者：MASANORI OGATA;SHINGO FUJITANI;KATSUNORI ITOH;

作者单位：Research Center, Shinagawa Refractories Co., Ltd. 707 Inbe, Bizen-shi, Okayama-ken 705-8577, Japan

刊名：Taikabutsu Overseas

ISSN：0285-0028

出版年：2002-01-05

卷：22

期：2

起页：132

止页：135

分类号：TQ175

语种：英文

关键词：

内容简介

The reaction between sulfur gas and refractories varies with temperature, atmosphere, and co-existing vapor. In an actual rotary kiln, the partial pressure of SO_3 is not high like the SO_3 gas reaction test, so, except for dolomite brick, there is no damage due to the reaction of SO_3 gas and refractories. However, in overseas research, some magnesia-chrome and magnesia spinel bricks have a comparatively large content of CaO, so, caution must be exercised for conditions of severe sulfur attack. Figure 9 shows the effect of sulfur in a rotary cement kiln. From the standpoint of reaction with "sulfur", care must be taken on cement clinker, steel plate joints, and the steel shell rather than refractories. However, even when sulfur does not react directly with refractories, it accelerates the wear by peeling and erosion, because of penetration of sulfur-containing materials (alkali sulfates, CaSO_4, PbS, etc.) into the refractory pores, resulting in structure deterioration and increased mechanical stress, due to the repetitive melting and solidification of the infiltrated and related compounds, and by the expansion effect that is higher than the refractories themselves. For that reason, as a characteristic property, refractories must be able to suppress the penetration of foreign constituents by means of reduced permeability and porosity, to minimize the effect of material that penetrates into the pores, and by optimizing the bonding structure. In the future, there will be increased effect(s) of sulfur and volatile matter, due to increased disposal of industrial wastes in rotary cement kilns. So, more research is needed to improve the refractories for rotary cement kilns, from the standpoint of pore size distribution and bonding structure.