Biomass combustion represents up to now a promising alternative for green energy generation. However, this process necessarily involves the production of considerable amounts of ashes that have to be disposed or reused with an adequate strategy. Although biomass ashes have been widely considered as an alternative feed for the building industry [1], actually their use as cement or aggregate replacement has been greatly limited by the chemical composition of the ashes themselves, mainly based on calcium phosphates and containing large amounts of chlorides, alkali and sulphates. Nevertheless, biomass ash can be promisingly regarded as partially reactive fillers for alkali-activated materials [2]. The latter, namely geopolymers, are in fact synthesized through the activation of an aluminosilicate with alkali metal hydroxides, silicates or phosphates at ambient temperature or slightly above, and are characterized by good mechanical properties, thermal and acid resistance, low environmental impact and low cost [3]. Their microstructure, composed of nanoprecipitates, is intrinsically porous and can be easily tailored with further additives to improve specific properties, as for example thermal conductivity. In this work mixed biomass ash has been used as partially reactive filler in a porous geopolymer material, with the aim to produce low cost and sustainable thermal insulating boards with load bearing abilities. The final formulation has been set up to maximize both the volume of disposed ashes and the thermo-mechanical properties of the obtained geopolymer. This study was developed in the frame of the project EEE-CFCC (www.eee-cfcc-it), POR FESR of E-R Region, Italy.
Biomass ash-based geopolymer for thermal insulation
A Natali Murri;E Landi;V Medri;
2017
Abstract
Biomass combustion represents up to now a promising alternative for green energy generation. However, this process necessarily involves the production of considerable amounts of ashes that have to be disposed or reused with an adequate strategy. Although biomass ashes have been widely considered as an alternative feed for the building industry [1], actually their use as cement or aggregate replacement has been greatly limited by the chemical composition of the ashes themselves, mainly based on calcium phosphates and containing large amounts of chlorides, alkali and sulphates. Nevertheless, biomass ash can be promisingly regarded as partially reactive fillers for alkali-activated materials [2]. The latter, namely geopolymers, are in fact synthesized through the activation of an aluminosilicate with alkali metal hydroxides, silicates or phosphates at ambient temperature or slightly above, and are characterized by good mechanical properties, thermal and acid resistance, low environmental impact and low cost [3]. Their microstructure, composed of nanoprecipitates, is intrinsically porous and can be easily tailored with further additives to improve specific properties, as for example thermal conductivity. In this work mixed biomass ash has been used as partially reactive filler in a porous geopolymer material, with the aim to produce low cost and sustainable thermal insulating boards with load bearing abilities. The final formulation has been set up to maximize both the volume of disposed ashes and the thermo-mechanical properties of the obtained geopolymer. This study was developed in the frame of the project EEE-CFCC (www.eee-cfcc-it), POR FESR of E-R Region, Italy.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
