A Brief Review of Solving Biomass Ash Deposition with Aluminum-silicate Based Additives and Future Perspective of Kaolin

Biomass as an abundant “green” renewable and CO2 neutral energy source have captured the entire world attention as a result of worsening energy crisis and environmental problems. Combustion of biomass have huge potentials of producing heat and power in a sustainable way. However, biomass fuels possess alkali metals i.e potassium (K) content which react with other ash forming elements i.e chlorine (Cl) to form alkali containing species i.e potassium chloride (KCl) which results in ash related operational problems (slagging and fouling). Kaolin; an aluminum-silicate based additive is regarded as the best additive at handling and capturing the problematic alkali containing species during biomass combustion with its ability to convert alkali containing species to high melting point potassium aluminum silicates (Kalsilite, Leucite). Therefore, this paper presents an overview of the mechanism of ash deposition, highlight key findings of aluminosilicate-based additives applications from previous studies and ends with kaolin future perspective.