Utilization of Hazardous Wastes and By-products as a Green Concrete Material through S/S Process: a Review

摘要

The disposal and treatment of hazardous industrial waste is very cost effective method for the industries, it has been a dormant issue. The new millennium brings challenges for the civil and environmental engineers and opportunities for research on the utilization of the solid waste and by-products and basic properties of concrete and its materials. The recycling of these materials attracts an increasing interest worldwide due to the high environmental impact of the cement and concrete industries. Normal concrete is manufactured using sand and stones, but lightweight concrete can be produced using industrial by-products and solid hazardous wastes such as expanded fly ash, slag, sludge, etc. The BDAT (Best Demonstrated Available Technology) stabilization/solidification (S/S) was applied for treatment of concrete contaminated solid hazardous wastes and by-products. The performance of concrete is measured in terms of physical, engineering, and chemical properties. Chemical and mineral admixtures help in the improvement of the lightweight concrete properties. Cement is replaced by the 15-35% fly ash in the concrete mix. Fly ash increases concrete strength, improves sulfate resistance, decreases permeability, reduces the water ratio required, and improves the workability of the concrete. Partial substitution solid hazardous waste does not strongly affect the strength of concrete and other properties. This mixed lightweight concrete is safe enough to be used in sustainable environmental applications, like roadbeds, filling materials, etc.