Effects of Replacing Fly Ash with Cutting Mud on the Performance of Ceramsite Aerated Concrete.

The cutting mud refers to the wastewater produced in the fabrication of ceramsite aerated concrete (CAC) blocks. To reduce the production and environmental impacts of these wastes, this paper puts forward a reuse plan that partially replaces the fly ash in CAC fabrication with the cutting mud. The dried powders in the mud of different concentrations were selected to replace an equivalent amount or a fewer amount of fly ash. The difference between the amount of dried powder and that of the fly ash being replaced was defined as the conversion coefficients. Then, the CACs fabricated under the equivalent replacement and under the converted replacement were compared in fluidity, compressive strength and dry density. The comparison shows that the CAC prepared when the cutting mud concentration is below 22% and the conversion coefficient is between 0.75 and 0.85 satisfies the production and quality requirements. Therefore, the wastewater produced in CAC fabrication can be treated effectively by replacing the fly ash with cutting mud. The replacement can reduce the harm and quantity of hazardous wastes, making them more recyclable. [ABSTRACT FROM AUTHOR]