Temperature Distribution Simulation and Optimization Design of Electric Heater for in-Situ Oil Shale Heating

Abstract

Electric heating is the main method of exploiting oil shale and electric heater is the key part of the heating element. In this paper, the temperature distribution of the electric heater was simulated by the Partial Differential Equation (PDE) of MATLAB, and orthogonal experiment analysis was also carried out to investigate the effects of different factors on the temperature distribution of the heater. The results showed that materials with low density were helpful to improve heating efficiency, and heat production, density and heat capacity had a great effect on the temperature distribution of the heater. The temperature distribution of the heater increased significantly with increasing heat production and radius of the heater, while higher heat capacity always led to the lower overall temperature of the heater. In addition, axisymmetric U-tube and vacuum heating tube were chosen as the heater, being of optimized shape, while copper and stainless steel were determined to be the optimized heater materials.

Numerical Simulation of Oil Shale Pyrolysis under Microwave Irradiation Based on a Three-Dimensional Porous Medium Multiphysics Field Model

“…The heating rate is slow and the energy consumption is very high. [49][50][51] Microwave heating The temperature rise is fast and pyrolysis efficiency is high.…”

Performance Prediction and Heating Parameter Optimization of Organic-Rich Shale In Situ Conversion Based on Numerical Simulation and Artificial Intelligence Algorithms

“…At present, the development technology of medium-low-maturity shale oil includes ground retorting and in situ conversion technology. − The retorting technology is suitable for shallow organic-rich shale, and it will produce a large amount of polluting gases, which is contrary to the concept of environmentally friendly development proposed by China. , In contrast, in situ conversion technology is considered to be an efficient, green, and feasible way. With the application and promotion of Shell’s ICP technology, research on electric heating in situ conversion has increased in China. , However, due to low permeability and poor thermal conductivity of shale, the heating efficiency of electric heating is low and the heating speed is slow . On this basis, convective heating attracts more attention, which is attributed to the pressurization effect, the increasing formation heating rate, the gas driving mechanism, and the enhanced hydrocarbon production. − Supercritical CO 2 has a high diffusion coefficient, low viscosity and surface tension, and the ability of strong permeability and solubility. , At the same time, it can also achieve a certain degree of carbon sequestration effect, which is consistent with the strategic goals of the carbon peak and carbon neutralization.…”

“…With the application and promotion of Shell’s ICP technology, research on electric heating in situ conversion has increased in China. 9 , 10 However, due to low permeability and poor thermal conductivity of shale, the heating efficiency of electric heating is low and the heating speed is slow. 6 On this basis, convective heating attracts more attention, which is attributed to the pressurization effect, the increasing formation heating rate, the gas driving mechanism, and the enhanced hydrocarbon production.…”

Numerical Simulation Analysis of Heating Effect of Downhole Methane Catalytic Combustion Heater under High Pressure

“…The electric heating wire is used to convert the electric energy into heat energy to heat the oil shale by heat conduction, or the electric energy is converted into heat energy through the electromagnetic induction effect of the excitation coil to produce high-temperature fluid in the form of thermal convection, heating oil shale. Previous research on downhole electric heaters mainly focused on the study of the influence of heaters with different structures (electric heating rods) and heater materials on heater performance [14][15][16][17][18]. The heat transfer area of the electric heating rod is small, and the low thermal conductivity of the oil shale makes the heating efficiency of heating the oil shale by heat conduction lower, and the cost is higher, which is not suitable for large-scale applications.…”