利用TG/DSC方法研究麦秆灰以及麦秆灰与石英混合物的高温熔融特性

TG /DSC ANALYSIS OF MELTING BEHAVIOR OF WHEAT STALK ASH AND MIXTURE OF WHEAT STALK ASH AND QUARTZ AT HIGH TEMPERATURE

利用热重差示扫描量热分析法（TG／DSC）对麦秆灰以及麦秆灰与石英混合物的高温熔融特性进行分析。通过引入模型化合物分析得出：麦秆灰以及麦秆灰与石英混合物在620—700℃内存在KCl和CaCl2混合物的共熔反应，熔融的KCl和CaCl2在800～900℃的温度区间开始转移到气相中。在空气气氛中，麦秆灰中的K2CO3与SiO2发生化学反应，生成K：SiO3，在901～1039℃的温度区间麦秆灰中的K2SiO3发生熔融。麦秆灰与石英混合物相对于单独的麦秆灰，KCl和CaCl2的熔融峰的温度区间无明显区别，而硅酸盐的初始熔融温度明显降低。

Melting behavior of wheat stalk ash and mixture of wheat stalk ash and quartz at high temperature was investigated with thermogravimetrie analysis （TG） and differential scanning calorimetry （DSC）. Model compounds were introduced for analyses. There was eutectie reaction between KC1 and CaCl2 in wheat stalk ash and in the mixture of wheat stalk ash and quartz at the temperatures between 620℃ and 700℃. Molten KCl and CaCl2 transferred to gas phase at the temperatures between 800℃ and 900℃. At air atmosphere, KECO3 can react with SiO2, forming potassium silicate. Potassium silicate in the wheat stalk ash melts at the temperatures of 901-1039℃. Comparing with the wheat stalk ash, there is no obvious difference for the range of melting temperatures of CaCl2 and KCl in mixture of wheat stalk ash and quartz, but the initial melt temperatures of silicate decreases markedly.