Calcination and characterization of low-grade fuel and kaolinitic clay blends

Kalyani Ambatipudi, Mani; Sinha, Priyanshu; Appadurai, Arun; Chaunsali, Piyush; S, Varunkumar

Abstract

Calcined clay blended cement (LC 3 types of cement) is one of the most promising solutions for CO 2 abatement in global cement industries. This study presents results on the characterization of products obtained in simultaneous calcination of kaolinitic clay blends co-fired with low-grade powdered fuels. Powdered rice husk is used as fuel and kaolinite clay is co-fired with rice husk. Calcination is performed in a nearly isothermal Moderate to Intense Low Oxygen Dilution (MILD) reactor. Results of co-firing experiments with a 1:1 ratio of biomass to clay with a nominal fuel feed rate of 5 – 6 kg/h are presented. This operating condition ensured that the particles are exposed to a temperature of 900–1100°C. The suitability of the obtained product was characterized using – (i) furnace tests, (ii) thermogravimetric analysis (TGA), (iii) X-ray diffraction (XRD) studies, and (iv) isothermal calorimetry. Furnace tests and TGA studies confirm the biomass conversion and clay conversion to be about 90% and 94% respectively. About 75% of calcination could be achieved compared to furnace-calcined clay. XRD analysis shows near complete conversion of kaolin peaks. Calcined clay exhibited a filler effect indicating its reactivity in Portland cement-clay blended system.

• Presentation Conference Type: Poster
• Conference Name: International Conference on Calcined Clay for Sustainable Concrete (CCSC 2022)
• Start Date: Jul 4, 2022
• End Date: Jul 7, 2022
• Publication Date: Jul 6, 2022
• Deposit Date: Jun 7, 2023
• Publicly Available Date: Jun 7, 2023
• Keywords: Calcined clays, Alternate fuels, Co-firing.
• Public URL: https://uwe-repository.worktribe.com/output/10762246
• Related Public URLs: https://ccsc.epfl.ch/program/