Improving the economic and environmental performances of the beet sugar industry in Slovenia: increasing fuel efficiency and using by-products for ethanol

This paper investigates the possibilities of attaining zero-waste emissions in the case of sugar production. The case-studied sugar plant located in Slovenia reflected a typical plant, using traditional sugar production from beet. An investigation of the possible use of waste and by-products from sugar processing was carried out, in order to approach zero-waste from beet sugar processing. The sugar production process was simulated and optimization was carried out concerning energy utilization. Consumption of energy in the chosen sugar plant was lowered by simultaneous optimization of the evaporation and crystallization process. Changing the fuel type used in the case-studied sugar plant (replacement of heavy fuel oil with natural gas) produced a significant decrease in air emission. Opportunities in the sugar industry have been discovered for adapting to new market conditions through the optimization of combined sugar–ethanol production. The two proposed options have been economically and environmentally evaluated and compared.