Life cycle assessment of the cogeneration processes in the Cuban sugar industry

The cogeneration process from sugarcane bagasse is an alternative way to reduce fossil fuels consumption. In the environmental assessment of products, processes and services the methodology of Life Cycle Analysis (LCA) is commonly used. This study aimed to evaluate and compare the environmental impacts of the life cycle of different cogeneration technologies currently used in the Cuban sugar industry. For doing this, a combination of nine steam generators models with eight turbogenerators was analyzed, for a total of 72 alternatives, using the Eco-indicator 99 and the software SimaPro. The electricity generated daily (1000 kWh) was the functional unit used for the analysis. The results showed that the reduction of this process emissions to the air, water and soil had a favorable effect on the categories of carcinogenesis, radiation, ecotoxicity and land use. The category of Human Health damages reached higher impacts in the cogeneration stage, which represented about 80% of the total environmental impact of the process. It was evidenced that the largest contribution to this category was the emissions of particulate material from bagasse combustion. The combination of the steam generator German Modified EKE 80 with the Russian turbogenerator 2500 was the alternative that involved a reduction of the total impact compared to the rest of alternatives.

► 72 alternatives of cogeneration from bagasse were evaluated by means the life cycle methodology.
► These systems emit appreciable amounts of particulate material to the atmosphere, affecting the human health.
► The cogeneration system that presents the smallest adverse effects on the environment is selected.
►  Beneficial impacts are demonstrated in several impact categories by concept of avoided product.