粒径对低钙粉煤灰颗粒多样特征的影响

Influence of particle size on various characteristics of low calcium fly ash particles

将来自不同地区的3种原状低钙粉煤灰按照颗粒尺寸分成多个粒径区间颗粒群,测试粒径分级颗粒群容重、化学组分、颗粒形貌及火山灰活性,并采用灰色关联分析法分析粉煤灰活性的影响因素。结果表明,随着粒径减小,粉煤灰颗粒群的容重增大,Fe2O3和SO3含量减小;当粒径小于80μm时,粉煤灰中Al2O3含量明显增大;粉煤灰的火山灰活性并未随粒径减小而一致增大,粒径大于40μm时,化学组分对粉煤灰火山灰活性的影响明显高于粒径的;粒径小于40μm时,由于玻璃相含量增大,粉煤灰的活性显著提高。

Three kinds of original low calcium fly ash from different regions were classified into several groups according to particle size.The bulk density,chemical constituent and pozzolanic activity of classified fly ash particle group were tested.Then the influencing factors of fly ash activity were analyzed by grey correlation analysis method.The results show that as the particle size decreases,the bulk density of fly ash increases while the Fe2O3 and SO3 mass contents decrease.When the particle size is less than 80μm,the mass content of Al2O3 increases greatly.The pozzolanic activity of fly ash does not increase with the decrease of particle size.When fly ash particles are larger than 40μm,chemical constituents have a greater influence on pozzolanic activity than particle size.When particles smaller than 40μm,the pozzolanic activity of fly ash increase significantly due to the increasing content of glass phase in small fly ash particles.