Neutron tomography analysis of refractory catables drying

• Grant number: 22/12406-0
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: February 01, 2023
• End date: May 31, 2023
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Victor Carlos Pandolfelli
• Grantee: Murilo Henrique Moreira
• Supervisor: Stefano Dal Pont
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Institution abroad: Université Grenoble Alpes (UGA), France
• Associated to the scholarship: 21/00251-0 - Analysis of refractory castables drying via computational modelling and neutron tomography, BP.DR

Abstract

Hydraulic bonded refractory castables are a partially saturated porous medium at the end of the curing stage. Hydrates precipitate and provide its mechanical strength, whereas the unreacted water is present as an adsorbed film of water on the walls of the porosity of the castable. Before reaching the operating conditions, the refractory linings must be appropriately dried. The major challenge at this stage is the risk of pressurization of water vapor originating from the evaporation of adsorbed water and dehydration, which can lead to the explosive spalling phenomenon, violent destruction of the lining due to a combination of thermomechanical stresses and the vapor pressure. Even though this process can also be seen in other critical scenarios, such as the response of Portland cement concrete structures under fire, this phenomenon is still not completely understood. Additionally, numerical models available in the literature and distinct laboratory experiments and development of different drying additives such as polymeric fibers have failed to help the reduction of the long drying process usually applied in the industry. Therefore, the current project aims to better understand the mechanisms that lead to drying as well as to obtain the required properties for the successful application of numerical models. For these purposes, neutron and X ray tomography analysis will be performed in refractory castables samples containing different organic fibers (polyethylene, polypropylene and celulose) during drying to finally explain the mechanisms of permeability increase and also obtain the required properties to model such materials. (AU)