Corrosion mechanism analysis of coal slag on SiC-CA6 composites

doi:10.3969/j.issn.1001-1935.2021.01.009

Refractories ›› 2021, Vol. 55 ›› Issue (1): 40-43.DOI: 10.3969/j.issn.1001-1935.2021.01.009

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Corrosion mechanism analysis of coal slag on SiC-CA₆ composites

Si Yaochen(), Xia Miao, Sun Honggang, Li Hongxia(), Du Yihao, Zhao Shixian, Shang Xinlian

State Key Laboratory of Advanced Refractories,Sinosteel Luoyang Institute of Refractories Research Co.,Ltd.,Luoyang 471039,Henan,China

Received:2020-05-19 Online:2021-02-15 Published:2021-02-15
Contact: Li Hongxia

煤熔渣对SiC-CA₆复合材料的侵蚀机制分析

司瑶晨(), 夏淼, 孙红刚, 李红霞(), 杜一昊, 赵世贤, 尚心莲

中钢集团洛阳耐火材料研究院有限公司先进耐火材料国家重点试验室河南洛阳 471039

通讯作者: 李红霞
作者简介:司瑶晨:男,1995年生,硕士。E-mail: 1650221915@qq.com
基金资助:
NSFC-河南联合基金重点支持项目(U1604252)

Abstract

Abstract:

The coal slag corrosion resistance of SiC-CA₆ composites was tested using the static crucible method under carbon embedded atmosphere at 1 500 ℃ for 3 h.The corrosion mechanism of coal slag on SiC-CA₆ composites was studied by means of XRD,SEM and EDS.The results show that:(1)in the reducing atmosphere,no obvious corrosion layer is found in the SiC-CA₆ composites;the formed permeation layer is relatively thin and dense,indicating that SiC-CA₆ composites have good slag corrosion resistance;(2)the corrosion mechanism of coal slag on SiC-CA₆ composites mainly includes two aspects: the oxidation of SiC particles at the slag/sample interface by iron oxide in the slag and the reaction of CA₆ in sample matrix with the SiO₂,Al₂O₃ and CaO in the slag to form CAS₂;the formed CAS₂ can dissolve into the slag and increase the viscosity of the local slag at the slag/sample interface,therefore suppressing the further penetration of the slag into the material.

Key words: silicon carbide-CA₆ composites, coal slag, static crucible method, corrosion mechanism, gasification

摘要：

采用静态坩埚法,在埋碳气氛中对SiC-CA₆复合材料进行了1 500 ℃保温3 h的抗煤熔渣侵蚀试验,通过XRD、SEM、EDS等分析了煤熔渣对SiC-CA₆复合材料的侵蚀机制。结果表明:1)在还原气氛下,SiC-CA₆复合材料中未发现明显的侵蚀层,形成的渗透层较薄且比较致密,表明SiC-CA₆复合材料具有较好的抗煤熔渣性能。2)煤熔渣对SiC-CA₆复合材料的侵蚀主要包括渣层界面处的SiC颗粒被渣中的铁氧化物氧化,以及基质中的CA₆与渣中的SiO₂、Al₂O₃、CaO反应生成CAS₂。CAS₂溶入渣中使得界面处局部区域内的熔煤渣黏度增大,抑制了熔渣向材料内部的进一步渗透。

关键词: SiC-CA₆复合材料, 煤熔渣, 静态坩埚法, 侵蚀机制, 煤气化

CLC Number:

TQ175

Si Yaochen, Xia Miao, Sun Honggang, Li Hongxia, Du Yihao, Zhao Shixian, Shang Xinlian. Corrosion mechanism analysis of coal slag on SiC-CA₆ composites[J]. Refractories, 2021, 55(1): 40-43.

司瑶晨, 夏淼, 孙红刚, 李红霞, 杜一昊, 赵世贤, 尚心莲. 煤熔渣对SiC-CA₆复合材料的侵蚀机制分析[J]. 耐火材料, 2021, 55(1): 40-43.

Figures/Tables 10

Fig.1 SEM photographs of fired sample

Fig.2 Illustration of static crucible slag resistance test

Fig.3 Profile of sample after slag test

Fig.4 XRD patterns of sample before and after slag test

Fig.5 SEM photograph of coal slag-sample interface after slag test

Fig.6 EDS pattern of white points in Fig.5

Fig.7 SEM photograph of area B in Fig.5

Fig.8 EDS result of point 1 in Fig.7

Fig.9 Comparison of main components of coal slag before and after slag test

Fig.10 Schematic diagram of slag corrosion

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