Life cycle assessment of wheat husk based agro-concrete block

In recent years the development of alternative insulation materials has increased, such as agro-concretes, a mix between inorganic binder and aggregate of vegetable origin, including farming waste, such as wood fiber, rice husk, hemp hurd. These type of insulator materials are more eco-sustainable, thanks to their renewable origin, and equally thermal efficient compared to the traditional ones. In particular, this study focused on the sustainability evaluation with Life Cycle Assessment (LCA) methodology of a wall made of wheat husk and a lime-based binder. The case study was analysed considering the entire life cycle of the wall, where thermal performances of the material, investigated in previous experimental activities, were taken into account for the use phase damage calculation associated with energy demand for winter heating and summer cooling. The obtained results were compared with two alternative scenarios, consisting in a wall made of traditional bricks fitted with a cladding and a wall composed with a unique casting of mixture of wheat husk and lime, having the same thermal transmissivity. The presence of the cladding influenced the choice of the most suitable end of life for the traditional wall, identified in landfill disposal, due to the presence of heterogeneous materials joined together by glue, while material recovery through recycling could be foreseen for the wheat husk-based materials. The comparative LCA analysis demonstrates that the two wheat husk based walls are characterized by better environmental performances compared to the traditional scenario for the production phase and end of life phase, where the main observed damage contribution are the natural gas consumption for the production of clay bricks and the emissions for landfill construction,