生物质与煤混合灰的熔融及黏温特性

Blending ash fusion and viscosity-temperature characteristics of biomass and coal

使用灰熔点测试仪研究了稻草、玉米秸秆、棉秆3种生物质分别掺入不同比例对鲍店煤灰熔融特性的影响,并利用高温黏度计考察了3种生物质掺入比例均为10%时对鲍店煤灰黏温特性的影响。结合X射线衍射仪分析测试结果,采用热力学计算软件FactSage得到了不同温度下灰渣熔融过程中物相及渣液内固含量的变化。结果表明:3种生物质掺混比例为10%～30%时,混合灰灰熔点均随生物质掺混比例的增加而降低,在较高的掺混比例下混合灰灰熔点呈现波动性,但均未高于煤的灰熔点。掺混比例为10%时,生物质的加入一定程度上改善了鲍店煤灰的黏温特性,可使气化炉操作温度下限降低约20℃左右。钙长石的生成是造成熔渣黏度迅速增加的主要原因。

The fusion characteristics of blending ash of Baodian coal and rice straw, corn straw, cotton straw at different blending ratios （10%-90%, step 10%） were investigated respectively using X-ray fluorescence （XRF） spectrometer, X-ray diffractometer （XRD）, and ash fusion point analyzer in reducing atmosphere. The characteristics of viscosity-temperature of blending ash at 10% blending ratio were also studied by high-temperature viscometer. The computer software package FactSage was used to predict the proportions of solid, the composition of the remaining liquid phase and the variation of phase. The results showed that the addition of 3 kinds of crop straw reduced the ash fusion temperature of Baodian coal at the blending ratio of 10%-30%. The fluctuation could be seen at the range of 40%-90%, but the fusion temperatures of hlending ash were less than Baodian coal ash. The viscosity-temperature characteristic of Baodian coal ash was improved by the addition of crop straw, and the lowest operating temperature of gasifier can be reduced by 20℃. Due to the emergence of anorthite, the viscosity increased with decreasing the temperature of melting ash.