Elaboración de concreto con adición de bagazo de café para incrementar su resistencia

Abstract

The decomposition of organic waste in landfills produces methane, a gas with a global warming potential 21 times greater than CO₂. Coffee bagasse (BC) is a significant organic waste in these landfills, so it is crucial to find a recycling solution to turn it into a valuable resource. The concrete industry can play an important role in increasing the recycling rate of this waste material. However, due to its high organic content, BC is not suitable for direct use in structural concrete. This research analyzed the pyrolysis of BC at different temperatures (350 and 349.50 degrees Celsius) to evaluate its suitability in improving the mechanical properties of concrete. Both raw and pyrolyzed forms of BC were used as replacements for fine aggregate (sand) in proportions of 5, 10 and 20 volume percent. Differential scanning calorimetry (DSC) analysis and compressive strength tests on concrete were performed to investigate the material properties and their behavior in concrete composites. The results show that the leaching of organic compounds from BC hinders the hydration reaction of cement particles, significantly affecting the compressive strength of concrete mixed with raw BC. However, pyrolysis of BC at 349.50 degrees Celsius markedly improved the material properties, resulting in a 22.39 percent increase in the compressive strength of concrete mixed with coffee biochar.