An electric-thermal-carbon multi-functional complementary distributed low-carbon energy supply system

Abstract

The application discloses an electric-thermal-carbon multi-energy complementary distributed low-carbon energy supply system, which comprises an internal combustion engine, a heat exchange mechanism, a phase change heat storage device and a carbon dioxide treatment mechanism. The cylinder liner water in the internal combustion engine is connected to the heat exchange mechanism through a first heat exchange pipeline, and the exhaust flue gas of the internal combustion engine is connected to the heat exchange mechanism through a second heat exchange pipeline. The first heat exchange pipeline and the second heat exchange pipeline are both driven by an absorption heat pump. The first heat exchanger has an exhaust port for discharging flue gas, and the exhaust port is connected to the carbon dioxide treatment mechanism through a flue gas injection pipeline. The second heat exchange pipeline is provided with the first heat exchanger for supplying heat to the carbon dioxide treatment mechanism. The exchanged heat energy in the heat exchange mechanism is stored through the phase change heat storage device. According to the energy utilization principle of 'temperature matching and gradient utilization', the associated gas energy is used for high-temperature power generation, medium-temperature decarburization and low-temperature heating. The application is a multi-energy complementary and gradient utilization near-zero carbon energy system.

Description

Technical Field

[0001] This invention relates to the field of energy supply technology, specifically to a distributed low-carbon energy supply system that is complementary to multiple energy sources including electricity, heat, and carbon. Background Technology

[0002] Distributed energy systems, as an advanced energy-saving and emission-reduction technology, are deployed near the demand side, directly serving users. They convert and consume cooling, heating, and electricity locally, possessing enormous potential to complement renewable energy and achieve efficient cascade utilization of energy. As a new type of end-user energy supply system, distributed energy systems are a powerful supplement to centralized energy supply; their organic integration represents the future direction of energy system development. Currently, distributed energy systems are widely developed in various forms, including power generation and combined cooling, heating, and power (CCHP).

[0003] As coal consumption gradually decreases, the proportion of renewable energy and clean fuels in the energy structure will increase rapidly. Distributed energy systems, primarily in the form of multi-energy complementarity and combined cooling, heating, and power (CCHP), will play an increasingly important role in the national energy system. Therefore, the industrialization of distributed energy has a broad market potential.

[0004] To address the above problems, this invention provides a distributed low-carbon energy supply system that achieves high-temperature power generation by combining electricity, heat, and carbon energy. Summary of the Invention

[0005] This invention provides a distributed low-carbon energy supply system that achieves high-temperature power generation by combining electricity, heat, and carbon energy.

[0006] The purpose of this invention is to provide an electric-heat-carbon multi-energy complementary distributed low-carbon energy supply system, including an internal combustion engine, a heat exchange mechanism, a phase change thermal storage device, and a carbon dioxide treatment mechanism. The cylinder liner water in the internal combustion engine is connected to the heat exchange mechanism through a first heat exchange pipeline, and the exhaust gas from the internal combustion engine is connected to the heat exchange mechanism through a second heat exchange pipeline. Both the first and second heat exchange pipelines are driven by an absorption heat pump. The first heat exchanger has an exhaust port for discharging combustion gases, and the exhaust port is connected to the carbon dioxide treatment mechanism through a flue gas injection pipeline. The second heat exchange pipeline is equipped with a first heat exchanger for supplying heat to the carbon dioxide treatment mechanism. The heat energy exchanged in the heat exchange mechanism is stored in the phase change thermal storage device, and one of the heat transfer pipelines of the phase change thermal storage device is connected to the cylinder liner water in the internal combustion engine.

[0007] Furthermore, it also includes an oil-water heat exchanger pipeline. The heat injection end of the oil-water heat exchanger pipeline is connected to the heat exchange mechanism, and the exhaust end is connected to the heat exchange mechanism through a low-temperature water source heat pump to form a crude oil heating circuit. The oil-water heat exchanger pipeline has an oil-water heat exchanger. The heat exchange structure includes a high-temperature water source heat pump and a second heat exchanger. The output end of the second heat exchanger is connected to the high-temperature water source heat pump.

[0008] Furthermore, it also includes connecting an absorption heat pump to the oil-water heat exchange pipeline between the heat exchange mechanism and the oil-water heat exchanger, according to the flow direction of the heat exchange medium in the oil-water heat exchange pipeline.

[0009] Furthermore, the carbon dioxide capture mechanism includes an absorption tower and a desorption tower. The absorption tower is connected to an absorption heat pump via a cooling pipeline, which includes a third heat exchanger and a booster fan. The carbon dioxide in the absorption tower is injected into the desorption tower for treatment and then discharged via a delivery pipeline. The delivery pipeline includes a fourth heat exchanger, a first solution pump, a fifth heat exchanger, and a second solution pump. The fourth heat exchanger is connected to the first solution pump, the first solution pump is connected to the fifth heat exchanger, and the output of the second solution pump is connected to the fourth heat exchanger.

[0010] The present invention has the following advantages: In accordance with the energy utilization principle of "temperature matching and cascade utilization", the present invention uses associated gas energy for high-temperature power generation, medium-temperature decarbonization and low-temperature heating, which is a near-zero carbon energy system with multi-energy complementarity and cascade utilization.

[0011] The absorption heat pump, low-temperature water source heat pump and high-temperature water source heat pump in this invention constitute a functional composite heat pump with a heat source temperature gradient improvement, and the low-temperature heat source can achieve a large temperature difference temperature gradient improvement.

[0012] In this invention, the exhaust gas from the gas-fired internal combustion engine undergoes an absorption-desorption process via a CO2 capture unit, achieving CO2 removal. Simultaneously, the energy consumption required for CO2 capture is derived from the exhaust gas itself, achieving "self-sufficiency" in CO2 capture of the exhaust gas. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the system structure of the present invention.

[0014] In the diagram: 1. Internal combustion engine; 2. Phase change heat storage device; 3. High-temperature water source heat pump; 4. Second heat exchanger; 5. Low-temperature water source heat pump; 6. Oil-water heat exchanger; 7. Absorption heat pump; 8. Third heat exchanger; 9. Booster fan; 10. Second solution pump; 11. First heat exchanger; 12. Desorption tower; 13. Fourth heat exchanger; 14. First solution pump; 15. Fifth heat exchanger; 16. Absorption tower. Detailed Implementation

[0015] This invention provides an electric-thermal-carbon multi-energy complementary distributed low-carbon energy supply system, including an internal combustion engine 1, a heat exchange mechanism, a phase change heat storage device 2, and a carbon dioxide treatment mechanism. The cylinder liner water in the internal combustion engine 1 is connected to the heat exchange mechanism through a first heat exchange pipeline, and the exhaust gas from the internal combustion engine 1 is connected to the heat exchange mechanism through a second heat exchange pipeline. Both the first and second heat exchange pipelines are driven by an absorption heat pump 7. The first heat exchanger 11 has an exhaust port for discharging combustion gases, and the exhaust port is connected to the carbon dioxide treatment mechanism through a flue gas injection pipeline. The second heat exchange pipeline is equipped with a first heat exchanger 11 for supplying heat to the carbon dioxide treatment mechanism. The heat energy exchanged in the heat exchange mechanism is stored in the phase change heat storage device 2, and one of the heat transfer pipelines of the phase change heat storage device 2 is connected to the cylinder liner water in the internal combustion engine 1.

[0016] In this embodiment, an oil-water heat exchanger 6 pipeline is also included. The heat injection end of the oil-water heat exchanger pipeline is connected to the heat exchange mechanism, and the exhaust end is connected to the heat exchange mechanism through a low-temperature water source heat pump 5 to form a crude oil heating circuit. The oil-water heat exchanger 6 is provided on the oil-water heat exchanger pipeline. The heat exchange structure includes a high-temperature water source heat pump 3 and a second heat exchanger 4. The output end of the second heat exchanger 4 is connected to the high-temperature water source heat pump 3.

[0017] In this embodiment, the oil-water heat exchange pipeline between the heat exchange mechanism and the oil-water heat exchanger 6 is connected to an absorption heat pump 7 according to the flow direction of the heat exchange medium in the oil-water heat exchange pipeline.

[0018] In this embodiment, the carbon dioxide capture mechanism includes an absorption tower 16 and a desorption tower 12. The absorption tower 16 is connected to the absorption heat pump 7 through a cooling pipe. The cooling pipe includes a third heat exchanger 8 and a booster fan 9. The carbon dioxide in the absorption tower 16 is injected into the desorption tower 12 through a conveying pipe for treatment and then discharged. The conveying pipe includes a fourth heat exchanger 13, a first solution pump 14, a fifth heat exchanger 15, and a second solution pump 10. The fourth heat exchanger 13 is connected to the first solution pump 14, the first solution pump 14 is connected to the fifth heat exchanger 15, and the output of the second solution pump 10 is connected to the fourth heat exchanger 13.

[0019] In this embodiment, the flue gas from the internal combustion engine 1 achieves CO2 removal through the CO2 capture unit, and at the same time provides a heat source for CO2 capture and analysis tower 12, thus achieving "self-sufficiency" in CO2 capture.

[0020] In this embodiment, the driving power source for the low-temperature water source heat pump 5 and the high-temperature water source heat pump 3 can be renewable energy electricity or the system's own power generation.

[0021] In this embodiment, following the energy utilization principle of "temperature matching and cascaded utilization," the associated gas fuel energy is used to power the gas internal combustion engine 1, remove CO2 from the CO2 capture and analysis tower 12, and heat the crude oil through the oil-water heat exchanger 6, achieving comprehensive cascaded utilization of energy and constituting a low-carbon energy system. Simultaneously, multiple energy inputs from the oilfield—associated gas, green electricity, and ground-source produced water—and multiple outputs—electrical load, thermal load, and CO2—achieve multi-energy complementarity and cascaded utilization, resulting in a synergistic integration of energy.

[0022] In this embodiment, the electricity generated by the internal combustion engine 1 driven by associated gas from the oilfield is used partly to power the low-temperature water source heat pump 5 and the high-temperature water source heat pump 3 to raise the temperature of the circulating hot water, partly to power the auxiliary equipment of the entire power supply system, and the remaining electricity is exported for production needs. The high-temperature exhaust gas (454°C) generated by the internal combustion engine 1 system drives the CO2 capture and desorption tower 12 to generate CO2. The exhaust gas (248°C) after the waste heat of the CO2 capture and desorption tower 12 is used to drive the absorption heat pump 7 to raise the cylinder liner water generated by the internal combustion engine 1 from 80°C to 95°C. The 95°C hot water is then used to raise the temperature of the crude oil from 37°C to 85°C using the oil-water heat exchanger 6. The low-temperature exhaust gas (100°C) after being used by the absorption heat pump 7 is cooled by the heat exchanger. The flue gas then enters the CO2 capture and absorption tower 16 to absorb CO2. After removing CO2, the flue gas is discharged from the top of the tower. The CO2-absorbing solution precipitates CO2 in the CO2 capture and desorption tower 12. The low-temperature hot water (47°C) passing through the oil-water heat exchanger 6 first passes through the low-temperature water source heat pump 5 to raise the temperature of the hot water to 66°C. The 66°C hot water, as a low-temperature heat source of the absorption heat pump 7, is cooled to 54°C after heat exchange in the second heat exchanger 4. The 54°C hot water is then heated to 71°C by the high-temperature water source heat pump 3. The 71°C hot water is then cooled to 80°C by the cylinder liner water cooling heat exchange of the internal combustion engine 1, and then further heated by the absorption heat pump 7. The phase change heat storage device 2 plays a role in actively regulating supply and demand matching.

[0023] In this embodiment, the 100°C flue gas, after being cooled by the third heat exchanger 8, enters the CO2 capture and absorption tower 16 via the booster fan 9. The CO2 is absorbed by the solution inside the tower and then discharged through the top of the tower. The CO2-absorbing solution is pressurized by the second solution pump 10 and heat-exchanged by the fourth heat exchanger 13 before entering the desorption tower 12. Inside the desorption tower 12, the solution is desorbed and separated under the heat of the 454°C flue gas. CO2 is separated at the top of the tower, and the solution from which CO2 has been desorbed is discharged from the bottom of the tower. After heat-exchanged by the fifth heat exchanger 15 and pressurized by the first solution pump 14, it enters the absorption tower 16 for the next CO2 capture process.

[0024] Although specific embodiments of the present invention have been described in detail with reference to the accompanying drawings, this should not be construed as limiting the scope of protection of the present invention. Various modifications and variations that can be made by those skilled in the art without inventive effort within the scope described in the claims are still within the scope of protection of this patent.

Claims

1. A multi-energy complementary distributed low-carbon energy supply system integrating electricity, heat, and carbon, comprising an internal combustion engine, a heat exchange mechanism, a phase change thermal storage device, and a carbon dioxide capture mechanism, characterized in that, The internal combustion engine is driven by associated gas from the oil field. Its cylinder liner water is connected to the heat exchange mechanism through a first heat exchange pipeline, and its exhaust gas is connected to the carbon dioxide capture mechanism through a second heat exchange pipeline. Both the first and second heat exchange pipelines are driven by an absorption heat pump (7), and wherein: The heat exchange structure includes an oil-water heat exchanger (6), a low-temperature water source heat pump (5), a second heat exchanger (4), a high-temperature water source heat pump (3), and a phase change heat storage device (2) arranged in sequence. The cylinder liner water is heated by the absorption heat pump (7) and then fed into the oil-water heat exchanger (6). After the crude oil is heated in the oil-water heat exchanger (6), it is fed into the low-temperature water source heat pump (5). After being heated by the low-temperature water source heat pump (5), it is fed into the second heat exchanger (4). After being heated by the low-temperature heat source of the absorption heat pump (7) in the second heat exchanger (4), it is fed into the high-temperature water source heat pump (3). After being heated by the high-temperature water source heat pump (3), it is fed into the phase change heat storage device (2). After being stored in the phase change heat storage device (2), it is returned and transported to the internal combustion engine cylinder liner. The carbon dioxide capture mechanism includes an absorption tower (16) and a desorption tower (12). The exhaust gas from the internal combustion engine first passes through the first heat exchanger (11) on the second heat exchange pipeline and then heats the desorption tower (12) in the carbon dioxide capture mechanism through the exhaust port of the exhaust gas set on the first heat exchanger (11). After that, it is passed into an absorption heat pump (7) to continue releasing heat. Then, it is passed into the absorption tower (16) through a cooling pipeline including a third heat exchanger and a booster fan. In the absorption tower (16), CO2 is absorbed by the solution inside the tower. After collection, the CO2 is finally discharged through the top of the tower. The CO2-absorbing solution is pressurized by the second solution pump (10) and heat-exchanged by the fourth heat exchanger (13) through the pipeline and then transported to the desorption tower (12). Under the drive of the high temperature flue gas heat in the desorption tower, CO2 is desorbed and separated and discharged through the top of the tower. The CO2-desorbed solution is discharged from the bottom of the desorption tower and then heat-exchanged by the fourth heat exchanger (13), pressurized by the first solution pump (14), and heat-exchanged by the fifth heat exchanger (15) before flowing back to the absorption tower (16) for the next CO2 capture process.

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