Bridging the agri-food and concrete industries. A systemic design approach for reducing waste and CO2 emissions

This essay explores the use of agri-food waste within circular design models to develop more sustainable building materials. Addressing the construction sector’s high energy demands and CO2 emissions, the text examines innovative approaches such as utilizing spent grain, a byproduct of beer production, and the chaff (husk of grains) from rice production as a replacement for fine aggregates in concrete. The study highlights the role of design in optimizing material and energy flows between systems to minimize environmental impact, aligning with principles of Industrial Symbiosis and Industrial Ecology. By examining two distinct socio-economic and industrial contexts, Mexico and Italy, the research emphasizes the significance of geographic and cultural factors. The beer industry is identified as a promising source of raw materials due to its substantial waste output, particularly spent brewing grains. Concrete modified with spent grain is evaluated for its physical-mechanical properties, considering both technical feasibility and broader economic and environmental implications. Likewise, byproducts like chaff and straw from rice cultivation, once considered mere waste suitable only for combustion, are now being recognized as valuable raw materials for a variety of applications, including concrete production. The analysis underscores the potential synergies between agricultural and industrial supply chains, contributing to the reduction of resource waste and CO2 emissions.