表面活性剂是常用的化学团聚促进剂,其促进效果与飞灰细颗粒的润湿性能密切相关。对飞灰细颗粒的化学组成及吸湿性能进行分析,利用沉降法考察了表面活性剂品种与浓度对飞灰细颗粒润湿性的影响,结果表明燃煤飞灰细颗粒多为难溶于水的硅铝质颗粒,可溶性组分仅有2.23%;而垃圾飞灰细颗粒含有较多的可溶性无机盐颗粒,可溶性组分含量高达49.47%。垃圾飞灰细颗粒吸湿性高于燃煤飞灰细颗粒。燃煤飞灰细颗粒在1 g/L的离子型表面活性剂中沉降时间最短;垃圾飞灰细颗粒在0.2 g/L的离子型表面活性中沉降时间可减少至9~12 s。非离子表面活性剂对飞灰细颗粒的润湿性好于离子型表面活性,其中以醚键为主要官能团的TX-10、OP-10和AEO3对飞灰细颗粒润湿性能好于以酯键为主要官能团的TWEEN80。
Surfactant is widely used as chemical agglomeration agent. The agglomeration properties were affected by the wettability of fly ash. The chemical composition and hygroscopic performance of fly ash were analysized. Sedimentation experiments were performed to study the effect of the species and concentration of surfactant on particles wettability in surfactant solution. The experimental findings showed the major constituent of coal fly ash was alumina silicate particle, in which the soluble constituent was only about 2.23%. Most of fine particles in waste fly ash were inorganic salts, in which the soluble composition was up to 49.47%. The hygroscopic performance of waste fly ash was higher than that of coal fin particles. The shortest sedimentation time for coal fly ash was in ionic surfactant with concentration of 1 g/L. The time of waste fly ash was reduced to 9-12 s in ionic surfactant with concentration of 0.2 g/L. Nonionic surfactant could wet fully the fly ash particles in a lower concentration. Some sorts of nonionic surfactant with ether group provided better wetting of fine particles, such as TX-10,OP-10 and AEO3. And, the wetting of some nonionic surfactant with ester group was not enough.