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چکیده
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The purpose of this study was to compare the environmental loads resulting from the two conventional operations for drying of medicinal plant extracts and to select effective variables to reduce impacts on a commercial scale. The boundaries of the system are limited on the production processes, including the production of maltodextrin carrier, extraction and drying of the extract. The functional unit of this study was 65.1 kg of product powder. SimaPro 9.0 was used to model the system with EcoInvent database. IMPACT 2002+ method was applied to estimate the environmental impacts. The data required to complete the inventory list, for the freeze-drying, were obtained from the manufacturer, and for spray drying, from published researches and the mass and energy balances. The results showed that the highest environmental loads in both drying processes are related to the extract production, and specifically, electricity consumption. By eliminating the common items of mass and energy, with the aim of comparing the two processes, it was shown that the freeze-drying method creates more environmental loads than spray drying. Sensitivity analysis was performed and efforts were made to improve the impacts in both processes. With the proposed opportunities for process improvement, the impacts were reduced by about 20% in the spray drying and by up to 31% in the freeze-drying.
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