An oil shale spiral heating device

Abstract

The present invention discloses a spiral heating device, specifically an oil shale spiral heating device. The device includes a temperature sensor, a thermal insulation shell, an inner shell, an automatic flow valve, a pressure sensor, electrode columns, a central tube, a baffle plate, heating plates, an insulating thermal insulation layer, a continuous spiral baffle plate and a PLC control system; by heating gas with the heating plates and combining the structural design features of the continuous spiral baffle plate and the heating plates of the present heater, the contact time between the gas and the heating plates is significantly increased, the residence time of the gas in the spiral heating device becomes longer, the heating efficiency of the downhole heater is significantly improved, effectively solving the problem that the outlet temperature of the heater is low under the same power of the heater. The outlet temperature of the oil shale spiral heater is significantly increased. At the same time, the heating cost is also greatly reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric heating equipment, and more specifically, it is an oil shale spiral heating device. Background Art

[0002] The world's oil shale resources are very rich. According to the resource reserve assessment, if the currently proven global oil shale resource reserves are converted into shale oil, the reserves can reach 6.9×10 11 tons, which is more than twice the currently proven crude oil reserves. The oil shale resource reserves in China can reach 73.91 billion tons, and when converted into shale oil, it is 48.74 billion tons, which is equivalent to 1.5 times the current conventional petroleum resources in China. Therefore, the exploitation and utilization of oil shale resources are of great strategic significance to China's development.

[0003] The development technologies of oil shale are divided into surface distillation technology and in-situ conversion technology. The surface distillation technology has strict requirements for rock formations and is generally only applicable to high oil-content oil shale formations with shallow burial and thick rock formations. At the same time, it will also cause the problem of "three wastes". The in-situ conversion technology has the advantages of not damaging the surface, being pollution-free to the environment, and being suitable for the development of deep oil shale.

[0004] There are three in-situ conversion heating methods: heat conduction, heat convection, and heat radiation. The heat conduction heating method places an electric heater in the wellbore to directly heat the target layer. A low-temperature gas is transmitted to the heater through a gas compressor on the ground, and then a high-temperature gas is generated after being heated by the heater to heat the kerogen of the oil shale to crack and produce shale oil. Since the residence time of the gas in the heater channel of a common heater is short and the gas cannot fully contact the heating plate, the temperature of the high-temperature gas at the gas outlet is lower than the ideal temperature and fails to meet the requirements. If the heating power of the heater is simply increased to increase the temperature of the gas outlet, the cost will be greatly increased. The present invention relates to the structural composition of an oil shale spiral heater. The oil shale spiral heater has adjustable heating power, high heating efficiency, uniform gas heating, and can effectively improve the heat exchange efficiency. The structure is safe and reliable for heating, and at the same time, it effectively solves the problem that the temperature of the heater outlet is low under the same power of the heater. The outlet temperature of the oil shale spiral heater is significantly increased, and at the same time, the heating cost is also greatly reduced, avoiding many deficiencies in existing products. Summary of the Invention

[0005] The purpose of the present invention is to provide an oil shale spiral heating device to solve the problems mentioned in the above background, such as the short residence time of the gas in the heater channel, the temperature of the high-temperature gas at the gas outlet being lower than the ideal temperature and failing to meet the requirements, uneven gas heating, low heat exchange efficiency, and high heating cost.

[0006] The present invention discloses an oil shale spiral heating device, which includes an inner shell, a heat preservation shell, an insulating heat preservation layer, electrode columns, a central tube, heating plates, an automatic flow valve, a temperature sensor, a pressure sensor, a continuous spiral baffle plate and a PLC control system. It is characterized in that a ground gas compressor provides low-temperature gas to the air inlet through a pipeline. The pressure sensor is arranged at the air inlet. The PLC control system can receive the detection signal of the pressure sensor at the air inlet and adjust the flow rate of the gas output by the gas compressor in real time automatically according to this detection signal. The automatic flow valve is arranged at the air inlet. The temperature sensor is arranged at the air outlet. The PLC control system can receive the detection signal of the temperature sensor at the air outlet and adjust the opening degree of the automatic flow valve in real time automatically according to this detection signal. The low-temperature gas enters the inner shell through the automatic flow valve at the air inlet and flows between the baffle plate and the heating plates in the direction of a spiral line inside the inner shell. Finally, high-temperature gas is discharged at the outlet. The present invention heats the gas through the heating plates. Combining the design features of the continuous spiral baffle plate and the heating plates of this heater, the heating efficiency of this heater and the heating time of the gas in the heater are significantly improved, effectively solving the problem that the outlet temperature of the heater is low under the same power, making the outlet temperature of the heater increase significantly. At the same time, the heating cost is also greatly reduced.

[0007] The present invention has the following advantages compared with the prior art:

[0008] 1. This spiral heating device can greatly reduce the heating cost.

[0009] 2. This spiral heating device solves the problems that the residence time of the gas in the heating body channel is short and the temperature of the high-temperature gas at the air outlet is lower than the ideal temperature and fails to meet the requirements.

[0010] 3. This spiral heating device solves the problems that the gas is unevenly heated in the heater and the heat exchange efficiency is low.

[0011] 4. This spiral heating device can realize real-time adjustment of the power of the heating plates through the PLC control system.

[0012] 5. This spiral heating device can realize real-time adjustment of the opening degree of the automatic flow valve through the PLC control system. Description of the Drawings

[0013] Figure 1 is the structural diagram of the embodiment of the present invention in the oil shale spiral heating device;

[0014] 1 - Air outlet 2 - Temperature sensor 3 - Heat preservation shell 4 - Inner shell 5 - Automatic flow valve 6 - Pressure sensor 7 - Air inlet 8 - Electrode column

[0015] Figure 2It is a cross-sectional view of the embodiment of the present invention in the oil shale spiral heating device;

[0016] 9 - Central tube 10 - Baffle plate 11 - Heating plate 12 - Insulating and heat-preserving layer

[0017] Figure 3 It is an axonometric view of the oil shale spiral heating device of the embodiment of the present invention;

[0018] 13 - Continuous spiral baffle

[0019] Figure 4 It is a cross-sectional gas flow diagram of the oil shale spiral heating device of the embodiment of the present invention; Specific embodiments

[0020] To further disclose the technical solution of the present invention, the following is a detailed description through embodiments in conjunction with the specification drawings: The present invention includes a temperature sensor (2), a heat-insulating shell (3), an inner shell (4), an automatic flow valve (5), a pressure sensor (6), an electrode column (8), a central tube (9), a baffle plate (10), a heating plate (11), an insulating and heat-preserving layer (12), a continuous spiral baffle (13) and a PLC control system. Among them, the temperature sensor (2), the automatic flow valve (5), the pressure sensor (6), the baffle plate (10), and the heating plate (11) are all controlled by a programmable PLC automatic control system. The internal structure of the heating device is composed of an inner shell (4), a central tube (9), a baffle plate (10), a heating plate (11) and a continuous spiral baffle (13). Among them, the heating plate (11) is installed on the outer circumference of the central tube (9), and is arranged in a specific angle in sequence and evenly on the 360° circumference of the outer circumference of the central tube (9) and passes through the continuous spiral baffle (13). The baffle plate (10) is installed on the inner circumference of the inner shell (4), and is arranged in a specific angle in sequence and evenly on the 360° inner circumference of the inner shell (4) and passes through the continuous spiral baffle (13). The heating plate (11) is seamlessly connected to the central tube (9), and there is a certain distance between the other end and the inner shell (4) to ensure gas flow. The baffle plate (10) is seamlessly connected to the inner shell (4), and there is a certain distance between the other end and the central tube (9) to ensure gas flow. Therefore, it ensures that the gas continuously bypasses the central area during the flow in the X direction, and successively passes through the turning paths of multiple cross-arranged baffle plates (10) and heating plates (11), forming a spiral or wavy flow-around motion. The gas flows and heats along the spiral direction in the Y direction. There are an automatic flow valve (5) and a pressure sensor (6) at the air inlet (1), and a temperature sensor (2) at the air outlet (7).

[0021] The working principle and working procedure of the present invention:

[0022] 1. Fully automatic control system:

[0023] At the beginning of the heating operation of the oil shale spiral heating device, the PLC control system starts to operate according to the working instruction. First, the automatic flow valve (5) is opened, and the low-temperature gas starts to be injected into the oil shale spiral heating device from the air inlet (6). The low-temperature gas flows in the oil shale spiral heating device in the shape of a spiral under the action of the continuous spiral baffle (13), the baffle plate (10) and the heating plate (11). During the flowing process, the low-temperature gas is gradually heated by the heating plate (11) into high-temperature gas, and then is discharged at the air outlet (1).

[0024] When the PLC detects through the temperature sensor (2) at the air outlet (1) that the temperature of the discharged gas is less than a certain specific temperature, the PLC control system automatically increases the heating power of the heating plate (11) through the feedback signal. At the same time, the PLC control system adjusts the opening degree of the automatic flow valve (5) in real time by feedback of the temperature sensor (2) signal, thereby reducing the flow rate of the low-temperature gas entering the oil shale spiral heating device. Since the opening degree of the automatic flow valve (5) decreases, the pressure at the air inlet (7) increases, and the signal of the pressure sensor (6) is fed back to the PLC control system to adjust the flow rate of the gas output by the ground gas compressor in real time, so as to make the high-temperature gas discharged from the air outlet (1) meet a certain set specific temperature.

[0025] When the PLC detects through the temperature sensor (2) at the air outlet (1) that the temperature of the output gas is greater than a certain specific temperature, the PLC control system automatically reduces the heating power of the heating plate (11) through the feedback signal. At the same time, the PLC control system adjusts the opening degree of the automatic flow valve (5) in real time by feedback of the temperature sensor (2) signal, thereby increasing the flow rate of the low-temperature gas entering the oil shale spiral heating device. Since the opening degree of the automatic flow valve (5) increases, the pressure at the air inlet (7) decreases, and the signal of the pressure sensor (6) is fed back to the PLC control system to adjust the flow rate of the gas output by the ground gas compressor in real time, so as to make the high-temperature gas discharged from the air outlet (1) meet a certain set specific temperature.

[0026] 2. Working principle:

[0027] The working principle of the present invention: In the heating process of the oil shale spiral heating device, first, the ground gas compressor supplies low-temperature gas to the oil shale spiral heating device through a pipeline. The low-temperature gas in the pipeline enters the inner shell (4) through the automatic flow valve (5) at the air inlet (7). The low-temperature gas starts to flow between the baffle plate (10) and the heating plate (11) in the inner shell (4) in the shape of a spiral, increasing the contact time between the gas and the heating plate (11). Finally, the high-temperature gas is discharged at the air outlet (1).

[0028] Although the present invention has been described in detail above using general descriptions, based on the invention, some modifications or improvements can be made, which are obvious to those skilled in the art. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection required by the present invention.

Claims

1. A spiral heating device for oil shale, which comprises a temperature sensor (2), a thermal insulation shell (3), an inner shell (4), an automatic flow valve (5), a pressure sensor (6), electrode columns (8), a central tube (9), a baffle plate (10), a heating plate (11), an insulating thermal insulation layer (12), a continuous spiral baffle plate (13) and a PLC control system. The internal structure of the heating device is composed of the inner shell (4), the central tube (9), the baffle plate (10), the heating plate (11) and the continuous spiral baffle plate (13). Among them, the heating plate (11) is installed on the outer circumference of the central tube (9), and is sequentially and evenly arranged in a circular pattern at a certain angle on the 360° circular circumference of the outer circumference of the central tube (9) through the continuous spiral baffle plate (13). The baffle plate (10) is installed on the inner circumference of the inner shell (4), and is sequentially and evenly arranged in a circular pattern at a certain angle on the 360° circular circumference of the inner side of the inner shell (4) through the continuous spiral baffle plate (13). The heating plate (11) is seamlessly connected to the central tube (9), and there is a certain distance between the other end and the inner shell (4) to ensure gas flow. The baffle plate (10) is seamlessly connected to the inner shell (4), and there is a certain distance between the other end and the central tube (9) to ensure gas flow. Therefore, it is ensured that the gas continuously bypasses the central area during the flow in the X direction, and sequentially passes through the turning paths of multiple cross-arranged baffle plates (10) and heating plates (11) to form a wavy flow-around motion. The gas flows and heats along the spiral direction in the Y direction. There are an automatic flow valve (5) and a pressure sensor (6) at the air inlet (7), and a temperature sensor (2) at the air outlet (1).

2. The oil shale spiral heating device according to claim 1, wherein The power of the heating plate (11) is controlled by the PLC control system. The PLC control system can receive the detection signal of the temperature sensor (2) at the air outlet, and automatically adjust the size of the power of the heating plate (11) according to the detection signal.

3. The oil shale spiral heating device according to claim 1, wherein The automatic flow valve (5) is controlled by the PLC control system. The PLC control system can receive the detection signal of the temperature sensor (2) at the air outlet (1), and automatically adjust the opening degree of the automatic flow valve (5) according to the detection signal.

4. The oil shale spiral heating device according to claim 1, characterized in that The ground gas compressor is controlled by the PLC control system. The PLC control system can receive the detection signal of the pressure sensor (6) at the air inlet (7), and automatically adjust the flow rate of the gas output by the ground gas compressor in real time according to the detection signal.

5. The oil shale spiral heating device according to claim 1, wherein An insulating thermal insulation layer (12) is filled between the thermal insulation shell (3) and the inner shell (4) to reduce the heat loss of the heater.

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