**Description of the system operation, in general lines.**

A trading system will be developed between the biorefinery and biogas plants (**Figure 7**):

• Biorefinery provide equipment needed to upgrade the biogas plants to be able to deliver sugar syrup (storage facilities, preservative chemical, press for harvesting sweet juice, evaporation equipment). Biorefinery provide as well a part of the spent biomass resulted after ethanol production process (containing low concentration of metals); vinasse resulted after distillation and other organic residues that can be used as feedstock for anaerobic digestion in biogas production.

