Resumen de Social life cycle assessment of low-tech digesters in small scale farms in Colombia
Kurt Ziegler Rodriguez, Irene Josa, Liliana Castro, Humberto Escalante Hernández, Marianna Garfi
Anaerobic digestion converts organic residues into renewable biogas and produces digestate, a valuable effluent that can be used as organic fertilizer. The use of digestate as fertilizer can enhance crop growth, improve soil quality, and reduce greenhouse gas emissions. However, digestate requires treatment to prevent the spread of pathogens or pollutants, depending on its feedstock and further use. In Colombia, small-scale farms implement anaerobic digestion to meet household energy demands and rely on selfsufficient farming. This study conducts a Social Life Cycle Assessment of a plastic tubular anaerobic digester in a Colombian small-scale farm and three digestate management scenarios: vermifilter, sand filter, and direct use on land. The study selected 1 kg of treated cow manure as a functional unit and collected primary information on-site and secondary information from literature and surveys. The main stakeholders include farmers, the local community, society, value-chain actors, women, and children. The main impact categories are human rights, labour conditions, socio-economic repercussions, human health, and education. The study found that the digester and filters have direct social benefits for farmers, such as improvements in crop quality and the health of inhabitants, and economic benefits in low-income rural communities.
