Glycerol Conversion: Chemical Kinetic Analysis and High Fidelity Solar Gasification

In this work the potential of converting crude glycerol into valuable syngas is assessed for an integrated zero waste biodiesel production process. The crude glycerol is the byproduct of the common transesterification process of lipid (vegetable and animal oil, grease and tallow). Biodiesel is been pursued as strong alternative to petro-diesel as awareness of fossil fuel deletion and climate change are at rise. In transesterification, one mole of glycerol is generated for each mole of lipid/triglyceride feedstock or per three moles of produced biodiesel. The quality and quantity of glycerol byproduct (10% of produced biodiesel) has been a burden for purification or direct combustion and risks of becoming an environmental disposal issue amid expanding biodiesel and saturated glycerol market. Therefore, integrating small to mid-size glycerol gasifier to the transesterification process offer a dually favorable impact, i.e. waste reduction and clean fuel production. Sample of crud and glycerol is analytically analyzed and their thermochemical conversion kinetics are inferred under both N₂ and O₂ pyrolysis/Combustion conditions. The kinetic parameters are used to model the gasification in high fidelity reactive model that simulate the injection of the glycerol in tubular gasifier setup at the beam down solar facility at Masdar Institute that provides the solar radiation heat. The model is based on an Eulerian-Lagrangian scheme that accounts for the discrete phase in the form of injected droplets in the continuous gaseous flow. The fluid is characterized as turbulent reactive flow of multiple species in radiative environment. Results achieved a maximum of 83 % (0.43 CO: 0.57 H2) suggesting the potential technoeconomical development of such gasifier and its integration.