doi:10.16186/j.cnki.1673-9787.2020050006

Received:2020/05/05

Revised:2020/06/03

Published:2021/11/15

Experimental study on activation of hydration activity of coal bottom ash in coal-fired power plant

LU Qianming1, ZHANG Yuanxin2, KUANG Zhaojie1, LI Yi1

1.School of Safety Engineering， Henan University of Engineering， Zhengzhou 451191 ， Henan， China， Zhengzhou  450121 ， Henan， Henan， China;2.Zhengzhou Technical College， Zhengzhou  450121 ， Henan， Henan， China

Abstract:In order to realize large-scale resource utilization of coal bottom ash ， the effects of mechanical grinding， microwave irradiation and chemical reagent addition on the hydration activity of coal bottom ash were investigated in this paper. The bottom ash and its cementitious samples were characterized by laser particle size analysis ， X-ray diffraction and scanning electron microscope. The results indicated that the specific surface area and bulk density peak of coal bottom ash increased with the extension of grinding time ， moreover ， the particle size distribution narrowed down and hydration activity improved at the same time. The hydration activity of coal bottom ash in the early stage could be significantly improved though microwave irradiation ， while the function of which appeared to be considerably smaller in the later stage. The compound additives had superior activation efficacy on coal bottom ash than that of single admixtures. When the content of CaCl， was 1.5% and triethanolamine was 0.03 % ， the 3D compressive strength of coal bottom ash-cement system increased greatly ， which was61.5% higher than that of the blank sample. The main hydration products of bottom ash-cement system were portlandite， calcium silicate aluminate hydrate and calcium chloroalminate hydrate. The addition of admixture promoted more hearth ash to participate in hydration reaction. The flaky calcium hydroxide and rod like hydrated calcium aluminosilicate in the hydrated product were wrapped in the gel to form a dense whole and improved the compressive strength of the sample.

Key words:coal bottom ash;mechanical grinding;microwave irradiation;mechanical property;hydration product

 燃煤电厂炉底灰水化活性激发试验研究_卢前明.pdf