硫酸铝对高掺量流化床粉煤灰基泡沫混凝土性能的影响  

Influence of Aluminum Sulfate on the Performance of High-content Circulating Fluidized Bed Fly Ash-based Foam Concrete

作　　者：董必钦[1] 张枭 刘源涛 何晓伟 王琰帅 DONG Biqin;ZHANG Xiao;LIU Yuantao;HE Xiaowei;WANG Yanshuai(Shenzhen Key Laboratory for Low-carbon Construction Material and Technology,Guangdong Province Key Laboratory of Durability for Marine Civil Engineering,College of Civil and Transportation Engineering,Shenzhen University,Shenzhen 518060,Guangdong,China)

机构地区：[1]深圳大学土木与交通工程学院,广东省滨海土木工程耐久性重点实验室,深圳市低碳建筑材料与技术重点实验室,广东深圳518060

出　　处：《材料导报》2024年第20期174-181,共8页Materials Reports

基　　金：国家自然科学基金(52108228,51925805)。

摘　　要：随着新型循环流化床燃煤技术的发展,循环流化床粉煤灰(CFBFA)的排放量日益增加。结合我国北方地区冬季严寒时保温隔热材料需求量大的现状,采用高掺量CFBFA制备具有保温隔热性能的泡沫混凝土。针对泡沫混凝土存在的凝结时间长以及早期强度低等问题,本工作掺入硫酸铝进行改性,研究并分析了硫酸铝掺量对泡沫混凝土密度、强度和导热系数的影响。利用X射线衍射(XRD)、热重分析(TG)以及扫描电子显微镜(SEM)等研究了硫酸铝作用下CFBFA基泡沫混凝土的水化产物和微观形貌。此外,还利用3D轮廓仪分析了泡沫混凝土的孔隙结构。结果表明,硫酸铝促进了本体系早期AFt的生成,与基准组(硫酸铝掺量为0%(质量分数,下同))相比,15%硫酸铝掺量的CFBFA基泡沫混凝土的初凝时间缩短了470 min,10%硫酸铝掺量的泡沫混凝土3 d强度可达到10.43 MPa,导热系数为0.31 W·m^(-1)·K^(-1)。这种泡沫混凝土具有较快批量化生产的潜力。With the development of the new circulating fluidized bed coal-burning technology,the emission of the circulating fluidized bed fly ash(CFBFA)is increasing.In this work,combined with the high demand of thermal insulation materials in northern China,high dosage CFBFA was used to prepare foam concrete with thermal insulation performance.To tackle the challenges of long setting time and low early strength in foam concrete,aluminum sulfate was introduced.The influence of aluminum sulfate mixture on the density,strength and thermal conductivity of foam concrete was studied.The hydration products and micromorphology of CFBFA-based foam concrete were analyzed by X-ray diffraction(XRD),thermal weight(TG)and scanning electron microscopy(SEM).Moreover,the pore structure of foamed concrete was tested by 3D contourometer.The results showed that aluminum sulfate promoted the early formation of ettringite in the system.Compared with the reference group(0%aluminum sulfate addition),the initial setting time of foam concrete with 15%aluminum sulfate addition was reduced by 470 minutes.The foam concrete with 10%aluminum sulfate addition achieved a 3-day compressive strength of 10.43 MPa and a thermal conductivity of 0.31 W·m^(-1)·K^(-1),showing its potential for efficient large-scale production.

关 键 词：泡沫混凝土 流化床粉煤灰(CFBFA) 隔热 无碱液体速凝剂 孔隙结构 

分 类 号：TU526[建筑科学—建筑技术科学]