Simulation, Analysis And Upgrading Of Sugar Multi-effects Evaporation

China is the world’s third-largest country of sugar industry, but China generally lag behind developed countries in production equipment and process technology of sugar refinery, it still presents enormous room for growth of energy conservation, emission reduction and rational utilization of resources. Multi-effects evaporation is the core of energy system in sugar refinery, it is both a high energy consumption process and an energy generation process, and therefore, its energy-saving upgrading is important for energy conservation of sugar refinery.In this research, Multi-effects evaporation is simulated by Aspen Plus software. Models of evaporator and multi-effects evaporation are established based on equipment theory and technological process. Aspen Plus models are verified by data from a five-effect evaporation process of sugar refinery in Yunnan Province, the result shows these models can simulate multi-effects evaporation process precisely.Based on Aspen Plus models, exergy analysis is applied to evaluate energy utilization level of multi-effects evaporation, and the change rules on the influence of feeding juice and steam is simulated, they can provided reference for energy-saving upgrading.By combining thermos economic and Aspen Process Economic Analyzer software, economic analysis is applied to evaluate economic effectiveness of different evaporation designs, and the four-effect and five-effect designs are at minimum long-term cost.Three upgrading measures are proposed for the existing problems, they are replacing heat-exchanger tube type of evaporator, adopting new entrainment separator and new inject atomizing condenser. By the application of Aspen Plus simulation, exergy and economic analysis, upgrading measures’ effect is evaluated, the result shows these measures can improve energy utilization level and economic effectiveness of multi-effects evaporation process.