The Influence of CO2 Curing on the Properties of Coal Gangue Non-Fired Blocks

Coal gangue is a solid waste, which can cause serious pollution of the atmosphere and water sources due to its long-term accumulation. In this article, the influence of CO2-cured coal gangue on the slump flow, the mechanical strengths, the thermal conductivity coefficient, the chloride ion permeability, the water resistance coefficient and the leached Pb of the coal-gangue-block masonry are determined. Moreover, the temperature distributions at different measuring points of a coal-gangue-block cabin model are obtained. The results exhibit that CO2-cured gangue demonstrates positive effects on the slump flow, the mechanical strengths and the thermal conductivity coefficient, with the slump flow rates increasing by 0%~23.6%, the mechanical strength rates increasing by 0%~222.7% and the thermal conductivity coefficient rates increasing by 0%~73.2%. Straw fibers increase mechanical strengths and decrease thermal conductivity at rates of 0%~222.7% and 0%~32.6%. Foam decreases the mechanical strengths and the thermal conductivity coefficient by 0%~71.2% and 0%~87.1%. The chloride ion migration coefficients are decreased by 0%~42.1% and 0%~43.7% with the added CO2-cured coal gangue and the straw fibers. The added foam leads to an increase in the chloride ion migration coefficient of 0%~73.2%. The foam and the straw fibers show delaying temperature changes in a coal-gangue-block cabin model, while when CO2-cured coal gangue is added, the effect is the opposite. The CO2-cured coal gangue and the straw fibers lead to decreases in the leached Pb and Zn, while when the foam’s mass ratio increases, the result is the contrary.

Dieses Werk wurde unter der Creative-Commons-Lizenz Namensnennung 4.0 International (CC-BY 4.0) veröffentlicht und darf unter den Lizenzbedinungen vervielfältigt, verbreitet, öffentlich zugänglich gemacht, sowie abgewandelt und bearbeitet werden. Dabei muss der Urheber bzw. Rechteinhaber genannt und die Lizenzbedingungen eingehalten werden.