Energy, Vol.185, 505-520, 2019
Study on Coil Optimization on the Basis of Heating Effect and Effective Energy Evaluation during Oil Storage Process
With the rapid development of crude oil reserves, energy consumption in heating increases gradually, so it is necessary to study heating effect and energy utilization. In this paper, a theoretical model of coil heating process for large floating roof crude oil tank is established, with dynamic thermal environment and variable physical parameters of oil products taken into consideration comprehensively. The influence mechanism of coil structure on the coupling characteristics of heat transfer and flow of crude oil during heating process is revealed. On this basis, the heating effect of crude oil in storage tank is evaluated from the point of view of time and space respectively. Simultaneously, the properties of energy and its quality are both considered, the effective energy utilization efficiency of crude oil in storage tank during heating process is analyzed, and an optimization method for heating coil of tank oil is proposed. The results show that the temperature of oil products in the center and bottom of the tank increases linearly with the influence of heat sources, and the temperature of oil products at the roof and wall of the tank is greatly affected by the dynamic thermal environment, which is showing a change regulation of fluctuating pattern. The heating effect is greatly affected by coil length. The increase of coil length can obviously improve the flow structure of crude oil in the tank. A larger eddy structure can be formed in a shorter period of time, which can increase the heating rate of crude oil and further reduce the non-uniformity of temperature field. However, effective energy efficiency is greatly affected by coil diameter. The increase of coil diameter increases the convective heat transfer coefficient between coil and crude oil, which promotes crude oil to absorb heat more easily from heat sources and improves the effective utilization of energy and exergy. Therefore, the heating effect and effective energy utilization of oil coil can be further optimized by changing the length and diameter of coil. Relevant research results can provide theoretical and technical support for improving the utilization efficiency of reserve energy and reducing the cost of reserve energy consumption. (C) 2019 Elsevier Ltd. All rights reserved.