Utilization of Calcium Carbide Residue Using Granulated Blast Furnace Slag.

Joonho Seo,Seon Hyeok Kim,Solmoi Park,Hyun No Yoon,Jeong Gook Jang,H K Lee

doi:10.3390/ma12213511

Abstract

The solidification and stabilization of calcium carbide residue (CCR) using granulated blast furnace slag was investigated in this study. CCR binding in hydrated slag was explored by X-ray diffraction, 29Si and 27Al magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy, and thermodynamic calculations. Mercury intrusion porosimetry and and compressive strength tests assessed the microstructure and mechanical properties of the mixtures of slag and CCR. C-A-S-H gel, ettringite, hemicarbonate, and hydrotalcite were identified as the main phases in the mixture of slag and CCR. The maximum CCR uptake by slag and the highest volume of precipitated solid phases were reached when CCR loading in slag is 7.5% by mass of slag, according to the thermodynamic prediction. This feature is also experimentally observed in the microstructure, which showed an increase in the pore volume at higher CCR loading.

Highlights

Harmful wastes generated by the results of industrialization are rapidly increasing beyond the limit of a naturally purifiable level in qualitative and quantitative aspects [1,2]
Organic wastes can be converted into innocuous substances by modifying the molecular structure of the wastes via incineration, while the dismantlement of inorganic wastes is far beyond simplicity except in some cases [3,4,5]
The solidification and stabilization (SS) method has been widely utilized as measures to stably dispose the inorganic wastes in a harmless way [2,6]

Summary

Introduction

Harmful wastes generated by the results of industrialization are rapidly increasing beyond the limit of a naturally purifiable level in qualitative and quantitative aspects [1,2]. These wastes must be safely disposed of through proper treatments so as to segregate them from living creatures. The SS typically refers to a method of immobilizing wastes, either physically or chemically, alone or in combination, to fix the wastes in a mass solidifier or to cover the superficial layer of the wastes [2,6]. Thereby, the SS process facilitates handling, improves physical and chemical properties, and inhibits leaching of the wastes

Methods

Results

Conclusion