Evaluation of sugarcane bagasse ash for lightweight aggregates production. (15th February 2021)

• Record Type: Journal Article
• Authors: Souza, Nathaly Santana Leal de; Anjos, Marcos Alyssandro Soares dos; Sá, Maria das Vitórias Vieira Almeida de; Farias, Evilane Cássia de; Souza, Maelson Mendonça de; Branco, Fernando G.; Pereira, Andreia
• Is Part Of: Construction & building materials. Volume 271(2021)
• Publication Date: 2021-02-15
• Subjects: Sugarcane Bagasse Ash -- Sintering -- Lightweight Aggregate -- Properties -- Microstructure; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2020.121604
• Languages: English
• ISSNs: 0950-0618

Abstract

Graphical abstract: Highlights: LWA were produced from sugarcane bagasse ash (SBA) and red clay. SBA were submitted to two different milling processes (knife and ball). Mixes with ratio SiO2 /ƩOF below 1.0 was less susceptible to bloating. The residue fineness (ball mill) corroborated for a better performance of LWAs. It was possible to formulate LWAs with a high content (90%) of waste (SBA). Abstract: The present paper aims at researching the development of lightweight aggregates from sugarcane bagasse ash (SBA) sintering and binary mixtures of SBA and red clay (RC). Two different SBA were evaluated, which differ on their milling process: one was produced in a ball mill and the other in a knife mill. The average particle diameters of the resulting SBA were 2.99 µm and 20.47 µm, respectively. Each of these mills was evaluated in binary mixtures of SBA and RC, varying the SBA contents from 50% to 90%. Pure SBA and RC were also evaluated. Six different sintering temperatures were studied (1000 °C, 1050 °C, 1100 °C, 1150 °C, 1175 °C and 1200 °C). The precursor materials were characterized in terms of chemical, mineralogical composition, particle size distribution, specific surface area and thermal analysis, to be subsequently pelletized and sintered. After sintering, the bloating index, particle density, loose bulk density, water absorption, voids index, crushing strength and morphology analysis by scanning electron microscopy (SEM) were assessed. The results demonstrate that it is possible to obtain lightweight aggregates based on binary mixtures of SBA and RC in a wide range of particle densities, ranging from 1.03 to 1.67 g/cm 3 and loose bulk densities ranging from 0.55 to 0.9 g/cm 3 . Bloating was observed only when smaller diameter SBA was used.