Pozzolanic properties of ultrafine sugar cane bagasse ash produced by controlled burning

Guilherme Chagas Cordeiro; Pryscila Vinco Andreão; Luís Marcelo Tavares

doi:10.1016/j.heliyon.2019.e02566

Pozzolanic properties of ultrafine sugar cane bagasse ash produced by controlled burning

Heliyon. 2019 Oct 9;5(10):e02566. doi: 10.1016/j.heliyon.2019.e02566. eCollection 2019 Oct.

Authors

Guilherme Chagas Cordeiro¹, Pryscila Vinco Andreão¹, Luís Marcelo Tavares²

Affiliations

¹ Laboratory of Civil Engineering, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brazil.
² Department of Metallurgical and Materials Engineering, Universidade Federal do Rio de Janeiro, COPPE/UFRJ, Rio de Janeiro, RJ, Brazil.

Abstract

This paper evaluated the feasibility of using residual sugar cane bagasse ash with a high carbon content (as-received SCBA) as raw material to produce a pozzolan after controlled recalcination and grinding. Initially, the as-received SCBA was re-burned using rotary (continuous) and muffle (batch) kilns, both at 600 °C for 1 h. Next, the resulting ash was ground in a closed-circuit ball mill with an air classifier system to obtain a product with 50% passing particle size of approximately 10 μm (SCBA600). SCBA600 was then characterized in terms of oxide composition, loss on ignition, density, specific surface area, and pozzolanic activity. A hydration study was carried out using isothermal calorimetry, thermogravimetric analysis and mercury intrusion porosimetry. Additionally, the performance of SCBA600 in mortars was evaluated by axial compression tests. The combination of recalcination at 600 °C, low-energy ultrafine grinding of the material and classification resulted in pozzolanic SCBA. The results also showed that including SCBA600 in cement mortars reduced total accumulated heat and portlandite content in cement-based pastes, in addition to refining pore structure and significantly increasing compressive strength after 3 days of curing.

Keywords: Civil engineering; Concrete technology; Construction engineering; Controlled burning; Hydration; Materials characterization; Materials science; Sugar cane bagasse ash; Ultrafine grinding.