Sunflower Residues-Based Biorefinery: Circular Economy Indicators
Fossil fuel price increases, their uneven distribution, environmental issues from their incineration, and lack of guarantees of their energy security are the main drivers for the development of green energy. Agricultural waste is an abundant resource for energy bioprocessing, which improves the functioning of the circular economy. In this study, the following were used as the main indicators: the share of renewable energy and the benefit from it, the coefficient of cyclical use of biomass, and the reduction in carbon dioxide emissions. The ways in which sunflower waste is applied for energy purposes are emphasized. The highest comprehensive ecological and economic effects are shown to be achieved in the production of biogas from sunflower residues with the incineration of this biogas in cogeneration plants. The residues from the biogas plant that are left after fermentation should be used as a biofertilizer. Such a cyclic system allows not only the full processing of all biomass waste that significantly reduces carbon dioxide emissions during the cultivation and processing of sunflower, but also an increase in the share of renewable energy used in technological processes up to 70%.