Preparation of concrete from vitrified slag: process parameter optimization and characterization

Abstract

ABSTRACT Vitrification is the safest and most effective method for treating solid waste incineration residues, and the utilization of vitrified slag can promote recovery of waste resources. By using the response surface methodology to comprehensively consider the impact of three factors – cement substitution ratio, water-binder ratio, and sand rate – on the strength of concrete, the optimal process parameters for predicting the maximum 28-day compressive strength of concrete specimens are determined as follows: 5% cement substitution ratio, 0.69 water-binder ratio, and 40% sand rate. The experiments demonstrate that concrete specimens prepared by partially replacing cement with molten glass slag exhibit excellent mechanical and physicochemical properties. As the curing age increases, the compressive strength of the specimens also enhances. Leaching test results showed that the concrete test block met groundwater Class III quality standards, and the addition of vitrified slag powder reduced the content of calcium hydroxide and improved concrete performance.