jismart2024082: Exploring the Applications of Wood Biomass Fly Ash in Geopolymer Development

Abstract

This paper aims to investigate the application of biomass fly ash discharged from biomass power plants in geopolymer mortar. Four series of geopolymer mortars were prepared to evaluate their performance, utilizing wood fly ash as the main binder, sourced from three different biomass power plants, with unburned carbon removed using the flotation method. In Series I, wood fly ash (WFA) and ground granulated blast-furnace slag (GGBS) were used as binders in a 7:3 ratio, with an alkaline solution (AS) to binder ratio of 65%. In Series II, only WFA was used as the binder based on the results of Series I. In Series III, 10% of the alkaline solution (AS) mass was added as water to the Series II mixes. In Series IV, WFA, coal fly ash (CFA), and GGBS were used as binders, with GGBS fixed at 40% and the combined content of CFA and WFA set at 60%. The results indicate that producing geopolymer mortar with 70% WFA and 30% GGBS, or 100% WFA as cementitious materials, is challenging. The fluidity of the mortar is relatively low, making it difficult to achieve a proper mortar consistency. Replacing part of the CFA with WFA in a geopolymer mortar composed of CFA and GGBS is a feasible approach. The results of Series IV indicate that compressive strength decreases with increasing wood fly ash content, while drying shrinkage decreases with the same increase in wood fly ash content.