EUBCE 2026 - Dennis KRÜGER - From Residue to Resource: An Innovative Solution for Energy Self-Sufficient Utilization of Coffee Husks

From Residue to Resource: An Innovative Solution for Energy Self-Sufficient Utilization of Coffee Husks

Short Introductive summary

Coffee, one of the world’s beloved beverages, unfortunately comes with a serious environmental challenge: the vast amounts of coffee husks left after processing, much of which are burned or discarded. This study introduces a holistic and energy self-sufficient concept for upgrading coffee husks into a renewable solid fuel through the combination of hot water extraction, biogas production, and heat recovery. In this process, soluble and odor-causing compounds are removed from the husks via water extraction and improving their combustion properties. The resulting liquid extract and low-grade husk fractions are then used to produce biogas, which supplies the thermal energy required for the extraction step, supported by heat recovery to maximize overall efficiency. The upgraded and pelletized coffee husks showed significantly improved fuel characteristics, making them suitable for clean cooking and heat generation. This concept offers a practical and circular pathway for coffee-producing regions, particularly in coffee producing countries, where access to clean biomass fuels is limited and deforestation for firewood and charcoal production remains a concern.

D. Krüger, Deutsches Biomasseforschungszentrum gemeinnützige, Leipzig, GERMANY
Ö. Mutlu, Deutsches Biomasseforschungszentrum gemeinnützige, Leipzig, GERMANY