Study On Energy Saving Of Vitamin Evaporation Crystallization Section With Self-heat Recuperation Technology

The vitamin, one of the most common sensible materials, is hard to get by evaporation crystallization, for its unsteadiness under high temperature. A new evaporation process is proposed based on self-heat recuperation technology(SHRT), while the conventional process has the disadvantages of high energy consumption, high discharge and poor quality of the vitamin product. Meanwhile, energy, characteristics and economical analysis are done on the new designed self-heat process.Firstly, the new vitamin evaporation is proposed with self-heat recuperation technology and the main model is created after recognizing problems remaining to be solved in the conventional process. Each state point is determined by energy balance and mass balance. The proposed self-heat process meet with the demand of the producing and the quality can be guaranteed by comparing with former one.The self-heat process is analyzed from the energy and exergy aspect to obtain the advantages over the conventional one. The three-link pattern of energy utilization is used to evaluate the specific link of the system. Results indicate that energy consumption of the self-heat process decreases 73%, while the exergy input decrease 68.3% than the conventional one. From the perspective of three-link pattern of energy utilization, 91% energy required energy is from the recycled heat, on the contrary, the conventional one’s source is external heat. What can be seen is that the energy structure of the self-heat process is more reasonable than the original process.The relation between energy consumption and the minimum heat transfer temperature difference are studied, as well as the effect of adiabatic efficiency on energy required. The results indicate that the advanced system with self-heat recuperation technology is able to save great energy and exergy. The energy input is decreased by 73.0% and the exergy input is decreased by 68.3%. There is a larger potential space for latent heat than sensible heat, which only accounts for 6.5% of the total heat recycled. Although larger minimum temperature difference needs less heat transfer area, it requires more energy input. Higher adiabatic efficiency and lower superheat mean less energy required.In order to solve the neglect of the influence of the system on the environment, a new comprehensive assessment index is proposed, monetizing the environmental cost and being used to research the economic properties. According to the index, a new single-factor impact method is created to analyze the factors influencing the producing cost. Results show that environment cost of new-designed process decreases 73%; The producing cost for 1kg production decrease with the rising working time; The established factor increases as the working time increases, ranging from 4.2%-8.4%; Energy investment and annual output has more impact on producing cost; Lager amount of the factor can enlarge the influence of each parameter and improve the related factor.