Utilization of Wood Biomass Ash in Concrete Industry

Abstract

The use of energy from wood biomass plants results in the production of large quantities of wood biomass ash (WBA). Most of the WBA is disposed of and some are used as a soil supplement in agriculture. In the concrete industry, there is a high potential for substitution of certain components with suitable alternative materials. Depending on its physical and chemical properties, WBA can be used in concrete production as a partial replacement for cement or as a substitute for fine aggregates. The suitability of locally available WBA should be evaluated in terms of microtexture, chemical, and mineralogical composition. This paper presents the types of WBA produced by different combustion technology, the influence of WBA as a cement replacement on the properties of cement composites in the fresh and hardened state, an overview of the environmental impact of WBA cement composites, and the market opportunities and readiness for reuse of WBA as a new potential supplementary cementitious material.

Biomass Bottom Ash as Supplementary Cementitious Material: The Effect of Mechanochemical Pre-Treatment and Mineral Carbonation

“…The replacement of cement with untreated biomass ash by 20% and 40% (BA20 and BA40 samples) resulted in a delay of approximately 2 h in the occurrence of the main hydration peak, which was reached after 11.6 and 12.5 h, respectively. Prolonged induction periods upon the addition of biomass ash are expected according to the literature and are related to the lower cement content and its replacement with a less reactive material [ 17 ]. Contrarily, the induction period was not significantly affected in the samples containing the mechanochemically treated and the carbonated mechanochemically treated biomass ash.…”

“…Two types of biomass ashes are produced; biomass fly ash (BFA), which is the fine and lightweight fraction that is transported by flue gases, and biomass bottom ash (BBA), which is the heavier and coarser slag comprised of sand, inorganic components, and unburnt particles [ 15 , 16 ]. To date, biomass ash is mostly disposed of via landfills, imposing risks on both the environment and human health [ 15 , 17 ]. To mitigate this risk, the immobilization of biomass ash in cementitious materials, valorised as SCM, is a promising solution and has been investigated in various studies [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ].…”

“…To mitigate this risk, the immobilization of biomass ash in cementitious materials, valorised as SCM, is a promising solution and has been investigated in various studies [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ]. The behaviour of biomass ash as SCMs depends significantly on their physicochemical properties, which are affected by the combustion process (type of feedstock biomass, temperatures used during combustion, method of collection and storage) [ 17 , 36 , 37 ]. The variation of the biomass ash composition has led to different observations regarding their effects on the mechanical performances and physical properties of cementitious materials across the literature.…”