Journal
WASTE MANAGEMENT
Volume 170, Issue -, Pages 103-111Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.wasman.2023.08.002
Keywords
Fly ash; Hypersaline brine; Solidification and stabilization; Thermodynamic modeling; Chemical reactivity
Categories
Ask authors/readers for more resources
This study evaluates the performance of combining two types of fly ash and different additives with two types of brine. The best-performing matrices are determined through experimental results and thermodynamic modeling, and system performance is predicted using a machine learning model.
The pozzolanic reaction of fly ashes with calcium-based additives can be effectively used to solidify and chemically stabilize (S & S process) highly concentrated brines inside a cementitious matrix. However, complex interactions between the fly ash, the additive, and the brine typically affect the phases formed at equilibrium, and the resulting solid capacity to successfully encapsulate the brine and its contaminants. Here, the performances of two types of fly ash (a Class C and Class F fly ash) are assessed when combined with different additives (two types of cement, or lime with and without NaAlO2), and two types of brine (NaCl or CaCl2) over a range of concentrations (0 & LE; [Cl ] & LE; 2 M). The best performing matrices - i.e., the matrices with the highest Cl-containing phases content - were identified using XRD and TGA. The experimental results were then combined with thermodynamic modeling to dissociate the contribution of the fly ash from that of the additives. All results were implemented in a machine learning model that showed good accuracy at predicting the fly ash degree of reaction, allowing for the robust prediction of extended systems performance when combined with thermodynamic modeling.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available