engleski

Mechanical properties of concrete containing wood biomass ash

Renewable energy, together with environmentally-friendly materials, gives us an insight into a sustainable future – one where reliance on fossil fuels and greenhouse gas emissions are minimised. The leading source of renewable energy in the EU are biomass fuelled power plants. Among different types of biomass, wood has the widest application while holding the majority share with 59% of all renewable energy sources. Nevertheless, combustion of 1 tonne of wood biomass generates approximately 3% of wood biomass ash (WBA), resulting in large amounts of waste. WBA management is an issue in need for prompt solutions, to avert further endangerment of the environment as well as disposal costs. Using WBA as partial cement replacement in cement composites is considered to be a feasible application. However, the fluctuating chemical composition of WBAs somewhat differs from coal fly ash, already acknowledged as a supplementary cementitious material. Due to the aforementioned difference and lack of standards and guidelines for WBAs application in cement composites, its wider application is still limited. Therefore, the main goal of this research was to quantify the acceptable amount of fly WBAs in concrete, while considering the chemical composition of different fly WBAs. Three WBAs utilized in this research were collected from different power plants located in Croatia, that exploit untreated wood chips as fuel while applying different combustion technologies. Six concrete mixtures were prepared with ash content of 15% and 20%. The impact of each WBA on concrete properties was analysed based on the determined compressive strength and modulus of elasticity. Differences between particular WBAs have been reflected on the properties of concrete mixtures.

wood biomass, fly ash, compressive strength, modulus of elasticity

nije evidentirano