Multi-energy combined storage and supply system based on SOFC-SOEC

Abstract

The invention discloses an SOFC-SOEC-based multi-energy combined storage and supply system, which comprises an SOFC unit and an SOEC unit, a first heat exchanger and a second heat exchanger are sequentially connected between the SOFC unit and the SOEC unit, the outlet of the first heat exchanger is connected with the SOFC unit and the second heat exchanger through pipelines, the first heat exchanger is further connected with a CO2 / H2O delivery pipe, and the CO2 / H2O delivery pipe is connected with a CO2 / H2O delivery pipe. CO2 / H2O is subjected to heat exchange and then sent to a third heat exchanger, and is subjected to heat exchange by the third heat exchanger and then sent to the feeding end of the second heat exchanger; an outlet of the SOEC unit is connected with the third heat exchanger through a pipeline and is used for heat exchange of CO2 / H2O; a first electromagnetic valve is arranged on a pipeline for connecting an outlet of the first heat exchanger with the SOFC unit, and a second electromagnetic valve is arranged on a pipeline for connecting the outlet of the first heat exchanger with the second heat exchanger; and the SOFC unit is connected with an air feeding pipe, a fuel feeding pipe and a water feeding pipe. According to the system, the energy conversion efficiency is improved, and efficient waste heat recovery is achieved.

Description

Technical Field

[0001] The present invention relates to the field of carbon neutrality technology, and in particular to a multi-energy storage and supply system based on SOFC-SOEC. Background Art

[0002] In order to solve the energy crisis and environmental pollution, achieving efficient combustion of fuels and the use of renewable energy is one of the effective means. Solid oxide fuel cell (SOFC) is a power generation device that directly converts chemical energy stored in fuel into electrical energy under high temperature conditions. Solid oxide electrolyzer (SOEC) is an electrochemical device that uses solid oxide as an electrolyte to electrolyze substances such as water or carbon dioxide under high temperature and applied voltage conditions. SOEC can convert carbon dioxide and hydrogen into synthesis gas, hydrocarbon fuels, etc., and store electrical energy and thermal energy in the form of chemical energy. How to improve the energy conversion efficiency of the multi-energy system of SOFC-SOEC and the efficient recovery of waste heat is an urgent problem to be solved in this field. Summary of the invention

[0003] Based on the technical problems existing in the background technology, the present invention proposes a multi-energy storage and supply system based on SOFC-SOEC, which improves the energy conversion efficiency and realizes efficient recovery of waste heat.

[0004] The multi-energy storage and supply system based on SOFC-SOEC proposed in the present invention comprises a SOFC unit and a SOEC unit, wherein a first heat exchanger and a second heat exchanger are connected in sequence between the SOFC unit and the SOEC unit, wherein an outlet of the first heat exchanger is connected to the SOFC unit and the second heat exchanger respectively through a pipeline, and the first heat exchanger is further connected to a CO2 / H2O delivery pipe, wherein CO2 / H2O is sent to a third heat exchanger after heat exchange, and then to a feed end of the second heat exchanger after heat exchange in the third heat exchanger; the outlet of the SOEC unit is connected to the third heat exchanger through a pipeline for heat exchange of CO2 / H2O; a first solenoid valve is arranged on the pipeline connecting the outlet of the first heat exchanger to the SOFC unit, and a second solenoid valve is arranged on the pipeline connecting the outlet of the first heat exchanger to the second heat exchanger; the SOFC unit is connected to an air feed pipe, a fuel feed pipe and a water feed pipe.

[0005] Preferably, a premixing unit is further included, the fuel feed pipe and the water feed pipe are connected to the premixing unit, the outlet of the premixing unit is connected to a reforming unit, and the outlet of the reforming unit is connected to the SOFC unit.

[0006] Preferably, the air feed pipe is also connected to a third heat exchanger, and the material transported to the SOFC unit by the first heat exchanger enters the water feed pipe after heat exchange by the third heat exchanger.

[0007] Preferably, the premixing unit comprises a tube body, one end of which is provided with a discharge port, the other end of which is connected to a fuel feed pipe and a water feed pipe, and a flow guide component is also provided in the tube body for achieving sufficient mixing of materials.

[0008] Preferably, the guide assembly includes a first guide plate and a second guide plate with openings in the middle, an outer guide tube is arranged between the first guide plate and the second guide plate, an inner guide tube is arranged inside the outer guide tube, one end of the inner guide tube is located inside the outer guide tube, and the other end of the inner guide tube passes through the second guide plate and is connected with the discharge port, and a gap is arranged between the outer guide tube and the first guide plate, the second guide plate and the inner guide tube to guide the material vortex to achieve sufficient mixing of the material.

[0009] Preferably, a reference tube is extended inwardly from one end of the tube body connected to the water feed pipe, the reference tube is provided with a plurality of first through holes, an adjusting tube is rotatably connected inside the reference tube, the adjusting tube is provided with a plurality of second through holes, and the water feed pipe is rotatably connected to the adjusting tube.

[0010] Preferably, the flow ratio r of the first solenoid valve and the second solenoid valve satisfies the following formula:

[0011]

[0012] Wherein, T1 is the outlet temperature of the first heat exchanger; T2 is the outlet temperature of the second heat exchanger; T1' is the temperature of the heat exchange medium of the first heat exchanger; T2' is the temperature of the heat exchange medium of the second heat exchanger.

[0013] Beneficial technical effects of the present invention:

[0014] (1) The present invention uses part of the product of the SOFC unit as the raw material of the SOEC unit, and the other part of the product flows back to the premixing unit of the SOFC unit, and the external heat source exchanges heat with the product of the SOFC unit through the second heat exchanger; at the same time, the CO2 / H2O transported to the SOEC unit from the outside sequentially exchanges heat through the SOFC unit product, the SOEC unit product and the second heat exchanger. The above scheme improves the energy conversion efficiency and waste heat recovery rate of the system, and the product of the SOEC unit after heat exchange can be processed in subsequent processes.

[0015] (2) The air feed pipe of the present invention is also connected to a third heat exchanger. The material transported to the SOFC unit by the first heat exchanger enters the water feed pipe after heat exchange by the third heat exchanger, thereby further improving the waste heat recovery rate and avoiding energy waste.

[0016] (3) The present invention is designed through the flow ratio of the first solenoid valve and the second solenoid valve. When the flow ratio r satisfies the proposed formula with the outlet temperature T1 of the first heat exchanger, the outlet temperature T2 of the second heat exchanger, the heat exchange medium temperature T1' of the first heat exchanger, and the heat exchange medium temperature T2' of the second heat exchanger, the optimal energy conversion efficiency and waste heat recovery rate can be achieved.

[0017] (4) The present invention achieves full mixing of materials through the design of the guide assembly structure, thereby improving the reforming effect of the fuel. Specifically, the materials in the fuel feed pipe and the water feed pipe enter between the first guide plate and the second guide plate. Due to the arc design of the first guide plate and the second guide plate, and the gap setting between the outer guide pipe and the first guide plate, the second guide plate and the inner guide pipe, the materials form a vortex between the first guide plate and the second guide plate. A part of the materials circulates between the first guide plate and the second guide plate, and the other part of the materials is discharged from the discharge port through the inner guide pipe.

[0018] (5) The present invention drives the regulating tube to rotate relative to the reference tube through a driving device (not shown in the figure) such as a motor. At this time, the material in the water feed pipe enters the tube body through the first through hole and the second through hole in sequence. Since the first through hole and the second through hole of the regulating tube are constantly misaligned during the rotation process, the pressure of the material jet in the water feed pipe changes continuously, thereby further improving the effect of mixing the material with the fuel. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the structure of the multi-energy storage and supply system based on SOFC-SOEC proposed by the present invention. Figure 2 This is a schematic diagram of the premixing unit structure of the multi-energy storage and supply system based on SOFC-SOEC proposed in the present invention.

[0020] In the figure: 1-reforming unit, 101-tube body, 102-first flow guide, 103-inner drainage pipe, 104-second flow guide, 105-discharge port, 106-first filter screen, 107-outer drainage pipe, 108-second filter screen, 109-first through hole, 1010-second through hole, 1011-feed port, 1012-regulating pipe, 1013-reference pipe, 2-SOFC unit, 3-first heat exchanger, 4-second heat exchanger, 5-SOEC unit, 6-first solenoid valve, 7-second solenoid valve, 8-third heat exchanger, 9-air feed pipe, 10-water feed pipe, 11-fuel feed pipe, 12-premixing unit, 13-fourth heat exchanger. DETAILED DESCRIPTION

[0021] The present invention will be further explained below in conjunction with specific embodiments.

[0022] Reference Figure 1The multi-energy storage and supply system based on SOFC-SOEC proposed in the present invention comprises a SOFC unit 2 and a SOEC unit 5, wherein a first heat exchanger 3 and a second heat exchanger 4 are connected in sequence between the SOFC unit 2 and the SOEC unit 5, wherein an outlet of the first heat exchanger 3 is connected to the SOFC unit 2 and the second heat exchanger 4 respectively through a pipeline, and the first heat exchanger 3 is also connected to a CO2 / H2O delivery pipe, wherein CO2 / H2O is sent to a third heat exchanger 13 after heat exchange, and is sent to a feed end of the second heat exchanger 4 after heat exchange in the third heat exchanger 13; the outlet of the SOEC unit 5 is connected to the third heat exchanger 13 through a pipeline for heat exchange of CO2 / H2O; a first solenoid valve 6 is arranged on the pipeline connecting the outlet of the first heat exchanger 3 to the SOFC unit 2, and a second solenoid valve 7 is arranged on the pipeline connecting the outlet of the first heat exchanger 3 to the second heat exchanger 4; the SOFC unit 2 is connected to an air feed pipe 9, a fuel feed pipe 11 and a water feed pipe 10.

[0023] The present invention uses part of the product of the SOFC unit as the raw material of the SOEC unit, and the other part of the product flows back to the premixing unit of the SOFC unit, and the external heat source exchanges heat with the product of the SOFC unit through the second heat exchanger; at the same time, the CO2 / H2O transported to the SOEC unit from the outside sequentially exchanges heat through the SOFC unit product, the SOEC unit product and the second heat exchanger. The above scheme improves the energy conversion efficiency and waste heat recovery rate of the system, and the product of the SOEC unit after heat exchange can be processed in subsequent processes.

[0024] In order to further improve the thorough mixing of fuel and water, a premixing unit 12 is also included. The fuel feed pipe 11 and the water feed pipe 10 are connected to the premixing unit 12. The outlet of the premixing unit 12 is connected to the reforming unit 1. The outlet of the reforming unit 1 is connected to the anode of the SOFC unit 2.

[0025] Reference Figure 2 As a preferred embodiment of the present invention, the premixing unit 12 includes a tube body 101, one end of which is provided with a discharge port 105, the other end of which is connected to a fuel feed pipe 11 and a water feed pipe 10, and a flow guide component is also provided in the tube body 101 for achieving sufficient mixing of the materials.

[0026] Specifically, the guide assembly includes a first guide plate 102 and a second guide plate 104 with openings in the middle, an outer guide tube 107 is arranged between the first guide plate 102 and the second guide plate 104, an inner guide tube 106 is arranged inside the outer guide tube 107, one end of the inner guide tube 106 is located inside the outer guide tube 107, and the other end of the inner guide tube 106 passes through the second guide plate 104 and is connected to the discharge port 105, and gaps are arranged between the outer guide tube 107 and the first guide plate 102, the second guide plate 104 and the inner guide tube 106 to guide the material vortex to achieve sufficient mixing of the material.

[0027] The materials in the fuel feed pipe 11 and the water feed pipe 10 enter between the first guide plate 102 and the second guide plate 104. Due to the arc design of the first guide plate 102 and the second guide plate 104, and the gap setting between the outer guide tube 107 and the first guide plate 102, the second guide plate 104 and the inner guide tube 106, the materials form a vortex between the first guide plate 102 and the second guide plate 107. A part of the materials circulates between the first guide plate 102 and the second guide plate 104, and the other part of the materials is discharged from the discharge port 105 through the inner guide tube 106. The present invention achieves sufficient mixing of the materials by designing the guide component structure, thereby improving the reforming efficiency of the fuel.

[0028] In addition, a reference tube 1012 is extended inward from one end of the tube body 101 connected to the water feed pipe 10, and a plurality of first through holes 109 are opened on the reference tube 1012. An adjusting tube 1011 is rotatably connected inside the reference tube 1012, and a plurality of second through holes 1010 are opened on the adjusting tube 1011. The water feed pipe 10 is rotatably connected to the adjusting tube 1011.

[0029] The regulating tube 1011 is driven to rotate relative to the reference tube 1012 by a driving device (not shown in the figure), such as a motor. At this time, the material in the water feed pipe enters the tube body 101 through the first through hole 109 and the second through hole 1010 in sequence. Since the first through hole 109 and the second through hole 1010 are continuously misaligned during the rotation of the regulating tube 1011, the pressure of the material jet in the water feed pipe is continuously changed, thereby further improving the effect of mixing it with the fuel.

[0030] In order to make full use of the waste heat, the air feed pipe 9 is also connected to the third heat exchanger 8. The material transported to the SOFC unit 2 by the first heat exchanger 3 enters the water feed pipe 10 after heat exchange in the third heat exchanger 8; the air in the air feed pipe 9 enters the cathode of the SOFC unit 2 after heat exchange.

[0031] The flow ratio r of the first solenoid valve 6 and the second solenoid valve 7 satisfies the following formula:

[0032]

[0033] Wherein, T1 is the outlet temperature of the first heat exchanger; T2 is the outlet temperature of the second heat exchanger; T1' is the temperature of the heat exchange medium of the first heat exchanger; T2' is the temperature of the heat exchange medium of the second heat exchanger.

Claims

1. A multi-energy storage and supply system based on SOFC-SOEC, characterized in that: The invention comprises an SOFC unit (2) and an SOEC unit (5), wherein a first heat exchanger (3) and a second heat exchanger (4) are connected in sequence between the SOFC unit (2) and the SOEC unit (5), wherein an outlet of the first heat exchanger (3) is connected to the SOFC unit (2) and the second heat exchanger (4) respectively through a pipeline, and the first heat exchanger (3) is also connected to a CO2 / H2O delivery pipe, wherein the CO2 / H2O is delivered to a third heat exchanger (13) after heat exchange, and then delivered to the second heat exchanger after heat exchange through the third heat exchanger (13). The outlet of the SOEC unit (5) is connected to the feed end of the heat exchanger (4) through a pipeline, and is used for heat exchange of CO2 / H2O; a first solenoid valve (6) is provided on the pipeline connecting the outlet of the first heat exchanger (3) and the SOFC unit (2), and a second solenoid valve (7) is provided on the pipeline connecting the outlet of the first heat exchanger (3) and the second heat exchanger (4); the SOFC unit (2) is connected to an air feed pipe (9), a fuel feed pipe (11) and a water feed pipe (10).

2. The multi-energy storage and supply system based on SOFC-SOEC according to claim 1 is characterized in that: It also includes a premixing unit (12), the fuel feed pipe (11) and the water feed pipe (10) are connected to the premixing unit (12), the outlet of the premixing unit (12) is connected to the reforming unit (1), and the outlet of the reforming unit (1) is connected to the SOFC unit (2).

3. The multi-energy storage and supply system based on SOFC-SOEC according to claim 2 is characterized in that: The air feed pipe (9) is also connected to a third heat exchanger (8), and the material transported from the first heat exchanger (3) to the SOFC unit (2) enters the water feed pipe (10) after heat exchange in the third heat exchanger (8).

4. The multi-energy storage and supply system based on SOFC-SOEC according to claim 2 is characterized in that: The premixing unit (12) comprises a tube body (101), one end of the tube body (101) is provided with a material outlet (105), the other end of the tube body (101) is connected to a fuel feed pipe (11) and a water feed pipe (10), and a flow guide component is also provided in the tube body (101) for achieving sufficient mixing of materials.

5. The multi-energy storage and supply system based on SOFC-SOEC according to claim 4 is characterized in that: The flow guide assembly comprises a first flow guide plate (102) and a second flow guide plate (104) with openings in the middle, an outer flow guide tube (107) is arranged between the first flow guide plate (102) and the second flow guide plate (104), an inner flow guide tube (106) is arranged inside the outer flow guide tube (107), one end of the inner flow guide tube (106) is located inside the outer flow guide tube (107), and the other end of the inner flow guide tube (106) passes through the second flow guide plate (104) and is connected to the discharge port (105), and a gap is arranged between the outer flow guide tube (107) and the first flow guide plate (102), the second flow guide plate (104) and the inner flow guide tube (106) to guide the material vortex to achieve full mixing of the materials.

6. The multi-energy storage and supply system based on SOFC-SOEC according to claim 4 is characterized in that: A reference tube (1012) is extended inward from one end of the tube body (101) connected to the water feed tube (10), and a plurality of first through holes (109) are formed on the reference tube (1012). An adjusting tube (1011) is rotatably connected inside the reference tube (1012), and a plurality of second through holes (1010) are formed on the adjusting tube (1011), and the water feed tube (10) is rotatably connected to the adjusting tube (1011).

7. The multi-energy storage and supply system based on SOFC-SOEC according to claim 1 is characterized in that: The flow ratio r of the first solenoid valve (6) and the second solenoid valve (7) satisfies the following formula: Wherein, T1 is the outlet temperature of the first heat exchanger; T2 is the outlet temperature of the second heat exchanger; T1' is the temperature of the heat exchange medium of the first heat exchanger; T2' is the temperature of the heat exchange medium of the second heat exchanger.

8. The multi-energy storage and supply system based on SOFC-SOEC according to claim 1 is characterized in that: The SOEC unit (5) is also connected to a photovoltaic power generation unit for supplying power to the SOEC unit (5).

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