钠基助熔剂对灵石煤灰熔融特性温度的影响

Effect of sodium based flux on the ash melting characteristics temperature of Lingshi coal

探讨了用钠基助熔剂降低灵石煤灰熔融特性温度亦称灰熔点的作用机理,采用XRD测试技术对煤灰及其添加钠基助熔剂后在不同热处理条件下的矿物质组成进行了分析,揭示了造成灵石煤灰熔点高的主要原因,以及添加钠基助熔剂降低灰熔融特性温度的助熔机理。实验还通过向灵石煤中添加生物质,考察了利用生物质灰中钠和其它碱金属化合物降低灵石煤的灰熔融特性温度的效果。研究表明:灵石煤灰硅铝化合物含量较高,在1 100℃以上形成的莫来石是导致煤灰熔点较高的主要原因,添加钠基助熔剂可以破坏硅铝氧化物的网状结构形成低灰熔融特性温度的长石类化合物,使煤灰熔点得到有效降低。

The effect of sodium based flux on the ash melting characteristics of Lingshi coal was investigated.The mineral compositions of Lingshi coal ash at different heat-treatment temperatures before and after adding sodium based flux were analyzed by XRD.The main reason that caused high ash fusing temperature of Lingshi coal ash was revealed.And the mechanism of reducing ash melting characteristics using sodium based flux was discussed and the network structure of silicoaluminate was damaged after adding sodium based flux for the formation of feldspar compounds which have lower ash fusion temperature.The results show that the formation of mullite at the temperature over 1 100 ℃ results in increasing of the melting point of coal ash,because of high content of silicoaluminate in Lingshi coal ash.Moreover,the Lingshi coal ash melting point also can be reduced by adding biomass ash,due to higher content alkali metal compound.