Lee Woong-Geol, Song Myong-Shin, Kang Seung-Min
Research Center of Advanced Convergence Processing on Materials, Kangwon National University, Samcheok 25913, Republic of Korea.
Technical Research Center, KC Green Materials Co., Ltd., Samcheok 25961, Republic of Korea.
Materials (Basel). 2023 Aug 7;16(15):5498. doi: 10.3390/ma16155498.
The by-products of the circulating fluidized-bed boiler combustion (CFBC) of coal exhibit self-hardening properties due to the calcium silicates generated by the reaction between SiO and CaO, and the ettringite generated by the reaction of gypsum and quicklime with activated alumina. These reactions exhibit tendencies similar to that of the hydration of ordinary Portland cement (OPC). In this study, the self-hydration and carbonation reaction mechanisms of CFBC by-products were analyzed. These CFBC by-products comprise a number of compounds, including FeO, free CaO, and CaSO, in large quantities. The hydration product calcium aluminate (and/or ferrite) of calcium aluminate ferrite and sulfate was confirmed through instrumental analysis. The CFBC by-products attain hardening properties because of the carbonation reaction between calcium aluminate ferrite and CO. This can be identified as a self-hardening process because it does not require a supply of special ions from the outside. Through this study, it was confirmed that CFBC by-products generate CaCO through carbonation, thereby densifying the pores of the hardened body and contributing to the development of compressive strength.
煤循环流化床锅炉燃烧（CFBC）产生的副产物具有自硬化特性，这是由于SiO与CaO反应生成的硅酸钙，以及石膏、生石灰与活性氧化铝反应生成的钙矾石所致。这些反应表现出与普通硅酸盐水泥（OPC）水化相似的趋势。在本研究中，分析了CFBC副产物的自水化和碳化反应机理。这些CFBC副产物包含大量的多种化合物，包括FeO、游离CaO和CaSO。通过仪器分析证实了铝酸钙铁氧体和硫酸盐的水化产物铝酸钙（和/或铁氧体）。CFBC副产物由于铝酸钙铁氧体与CO之间的碳化反应而获得硬化性能。这可被视为一个自硬化过程，因为它不需要从外部供应特殊离子。通过本研究证实，CFBC副产物通过碳化生成CaCO，从而使硬化体的孔隙致密化并有助于抗压强度的发展。
