Abstract:

Based on Aspen Plus, a total comminution fermentation process of aged rice with a capacity of 4 hundred thousand tons per year was designed and established. Exergy analysis method was used to study the thermodynamic properties of the process, and the source of exergy loss was clarified and optimized. The results showed that exergy loss was 106 477.62 kW before optimization, and the exergy loss was 79 108.84 kW after optimization. Meanwhile, the exergy loss was reduced by 27 368.78 kW and the exergy efficiency increased by 5.97% after optimization. The total energy consumption of 1 ton fuel ethanol production was 1 424.69 MJ, the raw material consumption was 4.25 ton, and the consumptions of water and wastewater were 2.9 and 0.37 ton, respectively. On the basis of meeting the demand of steam consumption in the production process, the power generation was 15.03 MW, and the system consumption was 12.9 MW. Through the economic analysis of the processes before and after optimization, the optimized process had better economy. The cost of public works decreased by 52.76%, the total cost decreased by 49.73 yuan per ton and the annual net profit increased by 2.85% after process optimization.

Key words: aged rice, fuel ethonal, simulation, energy consumption, exergy analysis