Thermal and CFD Study of a Heating Coil for a Bitumen Storage Tank

Thermal engineering study to estimate the additional heating power required to raise a mass of bitumen inside an existing storage tank from minimum ambient temperature up to 120°C within a 24 hour transient heating period, using the existing internal heating coil (58 mm external diameter). The study combined theoretical heat balance calculations with CFD simulation to capture convective losses and the non Newtonian behavior of bitumen, concluding that the existing coil can supply the required power if the heating fluid velocity is increased to 1 m/s and internal movement of the bitumen mass is promoted to improve convective heat transfer. Additional scenarios were evaluated, including an external half pipe coil and an external ring coil, the latter assessed further through FEA under a 72 hour heating condition, confirming that external coil solutions are significantly less efficient than the internal coil due to the poor thermal conductivity of bitumen, which behaves closer to an insulator than a conductor. Based on these results, the study delivered clear, practical recommendations, favoring internal heating with agitation or recirculation over external solutions, and identifying an internal electrical resistance as an alternative option for unattended weekend operation.