Thermo-economics evaluation of crude oil heating arranged with finned coil in floating roof tank

Abstract

The crude oil in the floating roof tank is troubled by the problem of gelling at low temperature which eventuate the storage of crude oil needs to be assisted by coil heating technology. However, the low heating performance of the technology restricts the benefits of crude oil storage due to the limited heat exchange area between coil and crude oil. A finned coil heating technology is proposed to address the above issues. The influence of the fin number and the inclination angle on the heating effect of crude oil is analyzed by FLUENT software. The results indicate that increasing the number of fins has a more significant effect on improving crude oil temperature than adjusting the inclination angle. The increase in the number of fins shows a nonlinear relationship with the increase in crude oil temperature, and there is an optimal combination for coils with different fin numbers and different inclination angles. From the perspective of thermos-economics, the optimal arrangement is the coil with 2 fins inclined at 60°, which can increase the crude oil zone average temperature by 2.83% (1.021 °C), and reduce the temperature inhomogeneity by 6.31%, as well as increase the cost saving by 91.65%, compared with the bare coil inclined at 0° (i.e. existing engineering formation). This paper is of great significance for ensuring the safe storage of crude oil.