(185f) A Novel Conceptual Design for Simultaneous Production of Biodiesel and Glycerol Carbonate from Soybean Oil

Biodiesel, a viable, non-toxic and biodegradable alternative to the conventional crude diesel, has prompted growing interest worldwide. Glycerol is the by-product of biodiesel production plant, the rapid increase in demand and production of biodiesel has resulted in excessive glycerol supply in the market. Converting the cheap glycerol into the high-value glycerol carbonate (GC) is a potential solution to the current worldwide excessive glycerol supply. GC, a green substitute for important petro-derivative compounds as ethylene carbonate or propylene carbonate, offers useful applications as a novel component of gas separation membranes, surfactant component, and a multipurpose green solvent for several types of materials. In this paper, a novel process for simultaneously producing biodiesel and GC using soybean oil as the main feedstock has been developed, the annual production capacities of 35.4 kilotonnes/yr of biodiesel and 4.4 kilotonnes/yr of GC are achieved. First, the simultaneous production of the biodiesel and GC has been investigated and simulated, glycerol from the biodiesel production is used as the feedstock for the GC production, while methanol, which is the by-product of GC production, can be supplied as the feedstock of the biodiesel production. Second, the operating conditions and configurations of distillation columns of GC production are optimized via thermal analysis, significant amounts of cooling/heating duties in condensers/reboilers of distillation columns are saved. Next, a mathematic model for heat integration of process streams has been built to minimize total utility costs, and thus a heat exchange network (HEN) is designed based on the optimal solution. Finally, economic evaluation for the simultaneous production of biodiesel and GC has been performed. The studied results show that the simultaneous production of biodiesel and GC is profitable, with a net present value (NPV) of $28,720,000 and a discounted cash flow return rate (DCFRR) of 60%.