Development of Room Temperature Curing Geopolymer from Calcined Water-Treatment-Sludge and Rice Husk Ash

Abstract

Geopolymer is an environmental friendly material, and is expected to use as the cement replacement materials. Because, the geopolymer production does not emit carbon dioxide gas, and is a low energy consuming process. Moreover, geopolymer can be synthesized from variety kinds of waste materials. The present work, the room temperature curing geopolymer has been developed by using the calcined water-treatment-sludge (WTS) and the rice husk ash (RHA) as the precursors. Mixture of sodium hydroxide solution and sodium silicate solution was used as an alkali activator solution. The results show that the RHA promotes strength of the WTS-geopolymer. By adding RHA 30 wt%, strength of geopolymer is close to the minimum required strength of the ordinary Portland cement (OPC). In addition, density of WTS-RHA geopolymer is 3 times lower than that of the OPC. Knowledge in the present work opens an opportunity to apply geopolymer for using in variety kinds of engineering applications, especially the lightweight construction materials.

Application of alkali-activated materials for water and wastewater treatment: a review

“…The S/S treatment method could also be potentially applied to extremely concentrated effluents such as reverse osmosis reject water (brine). Some water treatment sludges, on the other hand, are suitable raw materials for AAMs as they contain alumina and/or silicate and the resulting products can be used as masonry units, for instance (Belmokhtar et al 2016;Xu et al 2013;Yang et al 2009Yang et al , 2010Yang et al , 2013aGuo and Shi 2012;Antunes Boca Santa et al 2013;Chen et al 2009Chen et al , 2011Choi et al 2010;Yan et al 2016;Nimwinya et al 2016;Poowancum et al 2015;Suksiripattanapong et al 2015a, b, c;Horpibulsuk et al 2015). Table 2 compiles studies related to S/S of wastewater and solid WTRs.…”

Use of sludge from water treatment station to produce Geopolymer cement / Uso de lodo de estação de tratamento de água para produção de cimento Geopolimérico

“…The dosage used in the geopolymer production was based in two mixture variables: the molar ratio of SiO2/Al2O3 and the alkaline activator concentration because these factors directly influence the geopolymers properties (CHEN et al, 2016;GARCIA-LODEIRO et al, 2014;HOUNSI et al, 2014;LONGHI et al, 2016;POOWANCUM;HORPIBULSUK, 2015). For this reason, it was adopted a dosage with a SiO2/Al2O3 molar ratio equal to 3,0 combined with a sodium based alkaline activator in 10 mol.L -1 , whose mass of components is described in Table 1.…”

“…The production of Portland cement involves high temperatures for the obtainment of clinquer, which demands a large amount of energy and emits greenhouse gases, therefore, the civil construction has been seeking alternatives to replace it in the last years (FAN et al, 2018;POOWANCUM;HORPIBULSUK, 2015). Thus, the geopolymer is an innovative and alternative cementitious material to substitute the Portland cement (DAVIDOVITS, 2013).…”

Cenizas de cascarilla de arroz para la activación alcalina de cementantes binarios (ceniza volante/escoria de alto horno)

“…Se estima que el total de emisiones durante la fabricación de silicato de sodio tradicional equivale a 1,514 kg de CO 2 por cada 1 kg de silicato de sodio [5]. Así, fuentes alternativas de sílice son requeridas para reducir el impacto económico y ambiental que implica la producción del silicato de sodio, y en esa vía, las cenizas de cascarilla de arroz pueden representar una atractiva opción debido a su elevado contenido de sílice [1,[3][4][5][6][7], al considerar que tanto la parte amorfa como la cristalina tienen posibilidad de participar en los procesos de activación alcalina [8].…”