硅灰掺量对免烧粉煤灰陶粒性能的影响

以粉煤灰为原料,辅掺硅灰制备了碱激发免烧陶粒。采用筒压强度试验、吸水率试验、含泥量试验、磨破率试验、耐腐蚀试验、X射线衍射仪和扫描电子显微镜试验,系统地研究了硅灰掺量对陶粒性能的影响。结果表明,3 d、7 d、14 d龄期时,随着硅灰掺量增加,粉煤灰陶粒的筒压强度呈逐渐增加趋势,磨破率与吸水率呈逐渐下降趋势,耐腐蚀性能也得到提高。当硅灰掺量为15%和20%(质量分数)时,龄期为14 d时,陶粒的筒压强度分别达到19.43 MPa和20.37 MPa。由微观分析知,适量的硅灰掺量可以提高粉煤灰的水化程度,增加陶粒结构密实性,但当掺量达到15%~20%时,水化程度有所减弱。

Influence of Silica Fume Content on Performance of Non-Sintered Fly Ash Ceramsite

Alkali-activated non-sintered ceramsite was prepared with fly ash as raw material and silica fume as supplemented agent.The effect of silica fume content on ceramic properties was systematically studied by means of cylinder compressive strength test,water absorption test,mud content test,abrasion rate test,corrosion resistance test,X-ray diffractometer measurement and scanning electron microscope examination.The results show that at the age of 3 d,7 d,and 14 d,as the content of silica fume increases,the cylinder compressive strength of fly ash ceramsite gradually increases,while the abrasion rate and water absorption decrease gradually,and the corrosion resistance is also improved.When the silica fume content is 15%and 20%by mass,and the age is 14 d,the cylinder compressive strength of the ceramsite reaches 19.43 MPa and 20.37 MPa.According to the microscopic analysis,appropriate silica fume content increases the hydration degree of fly ash and the compactness of the ceramsite structure,but when the content reaches 15%to 20%by mass,the hydration degree is weakened.