Improvement of the Crude Glycerol Purification Process Derived from Biodiesel Production Waste Sources through Computational Modeling

Considering waste as a possible new resource for useful purposes is one of the strategies included in the circular economy principles. In fact, industrial processes are seen as great contributors to the formation of waste streams. With the aim to attain more sustainable and resilient systems, in this study, a process flow chart was elaborated in an Aspen Plus computer simulator, to obtain the production of pure glycerol from crude glycerol (a by-product of biodiesel production). This process occurs through fractional vacuum distillation, the methanol recovery route in the deacidification process and the removal of methanol from the reaction medium. The separation stages of the crude glycerol implemented enabled a degree of purification of 99.77%, meeting the specifications of the pharmaceutical use. The developed model allowed for the optimization of the purification process, raising by 40% the mass flow rate of pure glycerol. A conclusion could be drawn that the use of crude glycerol is an excellent option for the development of new products with greater added-value, contributing to the zero waste principles and to the circular economy.