甘蔗渣灰中金属氧化物对灰熔融特性的影响

Effect of Metal Oxides in Bagasse on the Fusion Characteristics of the Ash

采用灰熔点测定、SEM-EDS分析、FTIR分析和XRD分析,研究甘蔗渣灰成分中不同氧化物CaO、MgO、Fe 2 O 3对甘蔗渣灰熔融特性的影响。结果表明:甘蔗渣灰中CaO和Fe 2 O 3的加入使甘蔗渣灰熔点降低,MgO的加入使甘蔗渣灰熔点小幅提升;CaO的加入形成了多种碳酸盐以晶体形式存在,碳酸盐之间形成低温共熔物,使灰熔点下降;MgO的加入虽然生成了多种碳酸盐相互之间会形成低温共熔现象,但由于部分MgO仍以简单的金属化合物的形式存在未参与反应,使得灰熔点有小幅提高;Fe 2 O 3的加入形成低温共熔物硅酸盐,但尖晶石的存在使灰熔点变化不明显。甘蔗渣灰熔点低的主要原因是新硅酸盐类和新碳酸盐类物质的生成,使其灰熔点提高可从硅酸盐类和碳酸盐类物质的减少或者高熔点物质生成量增加两个角度进行考虑。

Ash melting point determination,SEM-EDS,FTIR and XRD were used to study the effects of different oxides CaO,MgO and Fe 2 O 3 on the melting characteristics of bagasse ash.The research results show that the melting point of bagasse ash decreased with the addition of Cao and Fe 2 O 3,and increased slightly with the addition of MgO;The addition of CaO forms a variety of carbonates in the form of crystals,and low-temperature eutectic forms between carbonates,which makes the ash melting point decrease;Although the addition of MgO produces a variety of carbonates that will form a low-temperature eutectic phenomenon with each other,the ash melting point is slightly increased due to the fact that part of MgO is still in the form of a simple metal compound and does not participate in the reaction;The addition of Fe 2 O 3 forms a low-temperature eutectic silicate,but the presence of spinel makes the ash melting point change insignificant.The main reason for the low melting point of bagasse ash is the formation of new silicates and carbonates.The increase of the ash melting point of bagasse can be considered from two aspects:the decrease of silicates and carbonates or the increase of high melting point substances.