title: Validating carbonation parameters of alkaline solid wastes via integrated thermal analyses: Principles and applications.
abstract: Accelerated carbonation of alkaline solid wastes is an attractive method for CO2 capture and utilization. However, the evaluation criteria of CaCO3 content in solid wastes and the way to interpret thermal analysis profiles were found to be quite different among the literature. In this investigation, an integrated thermal analyses for determining carbonation parameters in basic oxygen furnace slag (BOFS) were proposed based on thermogravimetric (TG), derivative thermogravimetric (DTG), and differential scanning calorimetry (DSC) analyses. A modified method of TG-DTG interpretation was proposed by considering the consecutive weight loss of sample with 200-900°C because the decomposition of various hydrated compounds caused variances in estimates by using conventional methods of TG interpretation. Different quantities of reference CaCO3 standards, carbonated BOFS samples and synthetic CaCO3/BOFS mixtures were prepared for evaluating the data quality of the modified TG-DTG interpretation, in terms of precision and accuracy. The quantitative results of the modified TG-DTG method were also validated by DSC analysis. In addition, to confirm the TG-DTG results, the evolved gas analysis was performed by mass spectrometer and Fourier transform infrared spectroscopy for detection of the gaseous compounds released during heating. Furthermore, the decomposition kinetics and thermodynamics of CaCO3 in BOFS was evaluated using Arrhenius equation and Kissinger equation. The proposed integrated thermal analyses for determining CaCO3 content in alkaline wastes was precise and accurate, thereby enabling to effectively assess the CO2 capture capacity of alkaline wastes for mineral carbonation.
authors.affiliation: Graduate Institute of Environmental Engineering, National Taiwan University, Taipei 10673, Taiwan.
authors.forename: Shu-Yuan
authors.initials: SY
authors.lastname: Pan
authors.affiliation: Department of Biochemistry, Taipei Medical University, Taipei 110, Taiwan.
authors.forename: E-E
authors.initials: EE
authors.lastname: Chang
authors.affiliation: Department of Environmental Engineering, University of Seoul, Seoul 130-743, South Korea.
authors.forename: Hyunook
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei 10608, Taiwan.
authors.forename: Yi-Hung
authors.initials: YH
authors.lastname: Chen
authors.affiliation: Graduate Institute of Environmental Engineering, National Taiwan University, Taipei 10673, Taiwan. Electronic address: pcchiang@ntu.edu.tw.
authors.forename: Pen-Chi
authors.initials: PC
authors.lastname: Chiang
keywords: Analytical; CO(2) fixation; Kissinger equation; Mineralization; Stabilization