- 目录
- 建筑石膏与胶凝材料
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CFB-FGD脱硫灰对水泥性能影响及机理研究
作者：刘进强1，2，刘姚君2，汪澜2，苏清发3
（1.唐山学院 环境与化学工程系，河北 唐山 063000；
2.中国建筑材料科学研究总院有限公司，绿色建筑材料国家重点实验室，北京 100024；
3.福建龙净脱硫脱硝工程有限公司，福建 龙岩 364000）
摘要：CFB-FGD脱硫灰中CaSO3·0.5H2O含量可达60%以上，对水泥性能影响与石膏有较大不同。对比研究表明，CFB-FGD脱硫灰在适宜掺量时对水泥凝结时间、抗压强度的影响与石膏的影响相当，但超量时容易导致抗压强度显著降低；与适量的石膏复掺性能会得到改善；随脱硫灰掺量的增加，对水泥与减水剂的相容性以及对水泥的体积稳定性无明显不良影响。CaSO3·0.5H2O与C3A反应生成C3A·CaSO3·11H2O，与AFm相类似，呈板片状。CaSO3·0.5H2O与同量的C3A反应会生成较多量的类AFm物，而非柱状、针状的AFt，是导致CaSO3·0.5H2O具有延缓水泥水化的作用，但不如石膏，且超量掺加时易对强度造成不良影响的主要原因。
关键词：亚硫酸钙；循环流化床；脱硫灰；水泥性能；机理
中图分类号：TU526 文献标识码：A 文章编号：1001-702X（2020）02-0084-04
Study of the effect and mechanism of CFB-FGD desulfurization ash on cement properties
LIU Jinqiang1，2，LIU Yaojun2，WANG Lan2，SU Qingfa3
（1. Department of Environmental and Chemical Engineering，Tangshan University，Tangshan 063000，China；
2.China Building Materials Academy，State Key Laboratory of Green Building Materials，Beijing 100024，China；
3.Lonjing Environment Technology Co. Ltd.，Longyan 364000，China）
Abstract：CaSO3·0.5H2O content in CFB-FGD ash is more than 60%，leading to the different effect on the performance of cement compared to gypsum. The comparative study shows that the CFB-FGD ash with proper dosage is equivalent to gypsum on the setting time and the compressive strength of cement，but may lead to a significant decrease in the compressive strength with the excess amount，and the performance can be improved if combined with an appropriate amount of gypsum simultaneously. There have no obvious adverse effects upon the compatibility between the cement and the water reducing agent，and the bulk stability of cement in the application of the CFB-FGD ash with increasing content. The hydration product of C3A is C3A·CaSO3·11H2O in the presence of CaSO3·0.5H2O which is similar to AFm in chemical structure and in morphology of sheet form. The hydration of C3A with CaSO3·0.5H2O than CaSO4·2H2O produces a larger amount of sheet-like AFm，other than columnar，needle-like AFt，which results in the different impact on the cement as mentioned earlier.
Key words：calcium sulfite，circulating fluidized bed，desulfurized fly ash，cement performance，mechanism