Significant energy savings in the beet sugar industry to reach the decarbonization goals

Abstract

Biomass-based energy (solid fuel or biogas) and green electricity take a growing share in today’s low-carbon/carbon-free energy sources. Contrary to industries with high-temperature energy consumption (e.g. steel or cement industries), the sugar industry uses relatively low-temperature energy (except for milk of lime production). To reach low-carbon/carbon-free reduction, the sugar industry will have to re-design its complete energetic scheme. The panorama of solutions answering the aforementioned questions are reviewed. Among these solutions, the optimization of the process by using existing well-known technologies is the 1st option: mechanical vapour re-compressors (MVR), heat pump, cogeneration technologies, by-product anaerobic digestion, etc. Combining these solutions will support the sugar industry to decrease significantly its specific energy consumption. As a reference, today’s sugar factories have a specific consumption between 900 to 1200 kWh of primary energy per tonne of sugar. A target for the future is to decrease the specific primary energy consumption to 620 kWh per tonne of sugar (without pulp drying). This new benchmark could be even improved in the case of using low-carbon electricity imported from the grid. How far could one go into the decarbonization of beets sugar factories? Is the objective of having net-zero emissions for sugar production realistic?