摘要
基于电容测试方法并辅以莫氏硬度对麦秆灰的烧结熔融特性进行研究。与常规热重-差热分析仪(TGDSC)测试和灰熔点测试方法相比,该方法测试便捷,得到的烧结温度(835℃)贴近气化炉内真实烧结温度。在此基础上,进一步考察温度、加热时间、气氛等影响麦秆灰熔融特性的条件。研究发现:温度是影响麦秆灰结渣与否的关键因素,在不同温度下,灰组分变化主要包括SiO2晶体的转变以及硅铝酸盐低温共熔体的生成,到达熔融温度990℃后,长石类矿物质特征峰消失,可能与玻璃体的生成相关;加热时间不影响烧结程度,N2气氛下麦秆灰在烧结温度下的理论烧结时间为5min,成钾长石的反应速率高于钙长石;在CO2、N2、空气3种气氛中,空气气氛下烧结温度略低,主要是因为在氧化性气氛下,麦秆灰更易于形成硅酸钾等低温共熔体。
The sintering behavior of wheat straw ash is examined based on capacitance test method accompanying with Mohs'hardness scale judgment.Comparing with the traditional test methods,such as TG-DSC test and ash fusion point test,the method is convenient to test,and the obtained sintering temperature is 835℃ which is close to the actual sintering temperature in the gasifier.On this basis,the conditions affecting the melting characteristics of wheat,straw ash,such as temperature,heating time and atmosphere are further investigated.The results show that the temperature is the key factor affecting the slagging of wheat straw ash.At different temperatures,the change of ash composition mainly includes the transformation of SiO2 crystal and the formation of low temperature eutectic of aluminosilicate.After reaching melting temperature of 990℃ ,the feldspar mineral characteristic peak disappears,which may be related to the formation of vitreous;In addition,it is found that the heating time does not affect sintering degree,the theoretical sintering time of wheat straw ash at sintering temperature is 5 min under N2 atmosphere,and the reaction rate of potassium feldspar is higher than that of anorthite;In the three atmospheres of CO2,N2 and air,the sintering temperature in the air atmosphere is slightly lower,mainly because the wheat straw ash is more likely to form a low temperature eutectic such as potassium silicate under an oxidizing atmosphere.
作者
李婷婷
黄艳琴
袁洪友
刘华财
阴秀丽
吴创之
Li Tingting;Huang Yanqin;Yuan Hongyou;Liu Huacai;Yin Xiuli;Wu Chuangzhi(CAS Key Laboratory of Renewable Energy,Guangzhou Institute of Energy Conversion,Chinese Academy of Sciences,Guangzhou 510640,China;University of Chinese Academy of Scienees ,Beijing100049,China)
出处
《太阳能学报》
EI
CAS
CSCD
北大核心
2018年第12期3490-3498,共9页
Acta Energiae Solaris Sinica
基金
国家自然科学基金(51306193)
关键词
麦秆灰
结渣
烧结温度
熔融特性
wheat straw ash
slagging
sintering temperature
fusion characterization
