Dezhi Zhao , Hexiang Wang , Caihong Xue , Qingxin Zhao , Wenyue Qi , Yuyang Tian
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引用次数: 0
Abstract
To achieve CO2 and municipal solid waste incineration fly ash (MSWI-FA) utilization in construction and building materials production, in this study a novel carbon mixing method was proposed to prepare cement-MSWI-FA pastes with improved properties. The effect of carbon mixing and curing on the compressive strength, Cl− as well as heavy metal solidification and pore structure was investigated. The reaction products were analyzed with XRD, SEM-EDS and TG to reveal the role of CO2 mixing on the phase assemblage development. The results showed that a ‘1.5 min normal mixing followed by 1.5 min carbon mixing’ procedure allowed the cement paste with 60 % MSWI-FA to obtain a compressive strength reaching 20 MPa at 28d. Compared with carbon curing, carbon mixing allowed easier and homogenous CO2 diffusion, and thus increased the CO32−/HCO3− in the pore solution for the formation of CaCO3 and Mc. The CaCO3 functioned as filler to refine the pore structure and thus contributed to the compressive strength improvement, while the Mc was converted to the Fs and AFt with the presence of Cl− and SO42− at 28d, enhancing the Cl− and heavy metals solidification. The proposed method and the test results of this study can provide technique support for the utilization of CO2 and MSWI-FA.
期刊介绍:
Cement & concrete composites focuses on advancements in cement-concrete composite technology and the production, use, and performance of cement-based construction materials. It covers a wide range of materials, including fiber-reinforced composites, polymer composites, ferrocement, and those incorporating special aggregates or waste materials. Major themes include microstructure, material properties, testing, durability, mechanics, modeling, design, fabrication, and practical applications. The journal welcomes papers on structural behavior, field studies, repair and maintenance, serviceability, and sustainability. It aims to enhance understanding, provide a platform for unconventional materials, promote low-cost energy-saving materials, and bridge the gap between materials science, engineering, and construction. Special issues on emerging topics are also published to encourage collaboration between materials scientists, engineers, designers, and fabricators.