改性油页岩渣-粉煤灰二元复掺的水化特征  

Hydration Characteristics of Calcined Oil Shale Residue-fly Ash Binary Compounding

作　　者：顾晓薇[1] 艾莹莹 孙维 GU Xiao-wei;AI Ying-ying;SUN Wei(College of Resource and Civil Engineering,Northeastern University,Shenyang 110819,China)

机构地区：[1]东北大学资源与土木工程学院,沈阳110819

出　　处：《科学技术与工程》2022年第34期15277-15283,共7页Science Technology and Engineering

基　　金：国家重点研发计划(2019YFC1907202);辽宁省重大科技专项(2020JH1/10300005)。

摘　　要：中国油页岩储量大,化学成分中硅铝含量虽然极高但火山灰活性却很低,作为掺合料替代水泥掺量局限于20%以下。为提高油页岩渣活性和掺量,以600℃煅烧2 h为活化基础,辅以高钙粉煤灰提供水硬性,复合掺量设置为30%,结合X射线衍射(X-rays diffraction,XRD)、扫描电子显微镜(scanning electron microscope,SEM)、能谱仪(energy dispersive spectrometer,EDS)与傅里叶红外光谱仪(Fourier transform infrared spectrometer,FTIR)的检测手段,探究复掺体系水化过程中水化产物的种类、形貌以及硅铝比。结果表明,改性油页岩渣活性源于脱油、脱水、脱羟基增大比表面积以及破坏油页岩渣中高岭土晶体从而产生的无定形铝硅酸盐物质;7 d活性指数达到97.4%,28 d活性指数达到85.8%;水化过程中改性油页岩渣先参与二次水化反应,Ca(OH)_(2)充足的前提下粉煤灰接着发生三次水化反应,若Ca(OH)2不充足,粉煤灰以内核的角色参与二次水化反应;反应体系中Al/Si值越大,C-A-S-H结合水的能力越强。由此可见油页岩渣与粉煤灰复掺能望应用于实际生产。A large reserves of oil shale are stored in China.Although the content of silicon and aluminum in the chemical composition is extremely high,the activity of pozzolan is very low.As an admixture to replace cement,the content is limited to less than 20%.In order to improve the activity and content of oil shale residue,based on calcination at 600℃for 2 hours,supplemented by high calcium fly ash to provide hydraulic hardness,the composite content was set to 30%,and the combination of X-rays diffraction(XRD),scanning electron microscope(SEM),energy dispersive spectrometer(EDS)and Fourier Transform Infrared Spectrometer(FTIR)the detection method was used to explore the type,morphology and silicon-alumina ratio of hydration products in the hydration process of the compound system.The results show that the activity of the modified oil shale residue originates from deoiling,dehydration,dehydroxylation to increase the specific surface area,and the amorphous aluminosilicate material are produced by destroying the kaolin crystals in the oil shale residue.the 7-day activity index reaches 97.4%,the activity index reached 85.8%in 28 days.During the hydration process,the modified oil shale residue first participated in the secondary hydration reaction,and the fly ash followed the tertiary hydration reaction under the premise of sufficient Ca(OH)_(2) is insufficient,and fly ash participates in the secondary hydration reaction as a core.The greater the Al/Si value in the reaction system,the stronger the ability of C-A-S-H to bind water.It can be seen that the combination of oil shale residue and fly ash can be expected to be applied in actual production.

关 键 词：油页岩渣 粉煤灰 活性指数 C-A-S-H 

分 类 号：TU521[建筑科学—建筑技术科学]