Producción de ladrillos ecológicos a partir de cáscara de arroz y sedimento de lago: consumo y optimización de...

For the past few decades, there has been a growing need to improve energy efficiency in brick production to reduce its environmental impact and support sustainable development. This study investigated the potential of partially replacing clay with treated lake sediment (LS), rice husk (RH), or mixtures of rice husk and treated lake sediment (RH-LS) in fired brick production. The brick samples were tested for density, linear shrinkage, water absorption, and compressive strength. Energy consumption during the firing process was monitored, and a comparison was made between conventional clay bricks and the novel brick formulations. The results revealed that it is possible to fabricate fired bricks using lake sediment blended with rice husk, incorporating up to 45% by weight of the alternative materials. These lightweight bricks met the technical standards for clay brick production, exhibiting a compressive strength exceeding 5.0 MPa, water absorption ranging from 13.8% to 31.3%, and linear shrinkage below 8.0%. The inclusion of LS and, particularly, RH, led to brick samples consuming 13% to 60% less energy and reducing CO₂ emissions by 0.9 to 2.7 times during the firing process. Additionally, the optimal 45% RH-LS brick samples reduced electricity consumption by 41% and CO₂ emissions by 2.3 times during sintering.Implications: Previous studies have proved the possibility of mixing sewage sludge from different origins (sewage sludge, river sediment, canal sediment, sewer sediment, etc.) with clay and some wastes to make bricks. For the last 05 years, our research group has explored the opportunities with lake sediment, sewer sediment and combination of both to reuse as construction materials. This study however provides the deep insight on energy saving and optimization, as well as calculation of CO2 emissions and carbon credits saving when employing lake sediment (pre-treated by constructed wetland), rice husk and clay for calcined brick production. The results showed that the optimum mixture of 45% clay replacement (18% rich husk and 27% lake sediment) was found to have the most energy-saving firing temperature at 950°C for 03 hr. With the integration of rice husk and lake sediment, the energy consumption was reduced by 13-60%, and CO₂ emissions were reduced by 0.86-2.7 times compared to traditional bricks. Specifically, the optimal 45% rice husk-lake sludge brick samples reduced electricity consumption by 41% and CO₂ emissions by 2.3 times during sintering.