A comprehensive energy service system for thermal power plants that incorporates hydrogen energy applications

Abstract

The invention discloses a comprehensive energy service system for a thermal power plant combined with hydrogen energy application. The outlet of a fuel system of the thermal power plant is sequentially connected to a burner on a boiler via a pulverizing system, the steam outlet of the boiler is connected to an inlet of a steam turbine, the exhaust steam outlet of the steam turbine is connected to industrial steam equipment, absorption refrigeration equipment and a heat release side of a heat exchanger; the output end of the steam turbine is connected to a driving shaft of a generator, the output end of the generator is connected to a public power grid and a plant power grid, the plant power grid is connected to an electrolytic hydrogen production device, an air separation device, a public gas preparation device, a compression refrigeration device and a compression heat pump, the output end of a distributed photovoltaic system is connected to a power supply interface of an electrolytic hydrogen production device, the hydrogen outlet of the electrolytic hydrogen production device and the nitrogen outlet of the air separation device are connected to the inlet of an ammonia reactor, and the outlet of the ammonia reactor is connected to an ammonia burner on the boiler. The system can realize the combination of comprehensive energy services and hydrogen energy.

Description

Technical Field

[0001] The present invention relates to a comprehensive energy service system for a thermal power plant, and in particular to a comprehensive energy service system for a thermal power plant combined with hydrogen energy application. Background Art

[0002] At present, the starting point of integrated energy services is mainly on the grid side and the user side, and its main technical route is the energy supply system composed of wind-solar storage, solar-storage charging, and various heat pumps, cold storage devices, etc. Domestic power generation companies have carried out integrated energy services based on natural gas distributed energy stations, but research on integrated energy services based on the source side of thermal power plants has not been reported.

[0003] Integrated energy services are one of the ways to reduce carbon emissions and achieve green and low-carbon transformation. The use of hydrogen energy can achieve large-scale and efficient consumption of renewable energy; redistribute energy between different industries and regions; act as an energy buffer carrier to improve the resilience of the energy system; reduce carbon emissions in the transportation process; reduce carbon emissions in the industrial energy sector; replace coke in the metallurgical industry to reduce carbon emissions, and reduce carbon emissions in building heating. my country's hydrogen energy development is currently mainly focused on the construction of hydrogen fuel cell vehicles and supporting hydrogen refueling stations. However, as a secondary energy source, the potential of hydrogen energy is far more than hydrogen fuel cell vehicles. The use of hydrogen energy to build a future low-carbon integrated energy system in the fields of electricity, industry, and heat has been proven to have great potential.

[0004] The main use and development direction of hydrogen energy is to use hydrogen as a raw material in industrial raw materials, direct combustion energy supply, household fuel cells and fuel cell vehicles. The relevant technologies have made great progress in recent years. However, the core of the development of emerging energy is to achieve low-cost and efficient raw material sources and storage and transportation, and hydrogen energy development also faces the same problem. Therefore, hydrogen production and storage technology is the key to the efficient use of hydrogen, an important bottleneck restricting the large-scale industrial development of hydrogen energy, and one of the key points and difficulties in the current industrial development of hydrogen energy. Ammonia (NH3) is a good carrier of hydrogen energy. Compared with hydrogen (H2), the main advantages of ammonia are high hydrogen content and high volume energy density. The unit volume hydrogen content and volume energy density of liquid ammonia are even higher than those of liquid hydrogen. At the same time, due to its mature production process, easy liquefaction for storage and transportation, and high safety, it is considered to be a more potential clean fuel that can effectively serve as a carrier of hydrogen and energy.

[0005] According to the EU's hydrogen energy utilization plan, in terms of hydrogen production, PtG technology is mainly used to maximize the solution to the problem of renewable energy utilization and transportation in Europe. PtG technology uses surplus renewable energy to electrolyze water, converts electrical energy into hydrogen, and realizes the utilization and long-term storage of renewable energy in the form of chemical energy. The hydrogen obtained by electrolysis can be directly used in transportation, industrial utilization or gas-fired power generation. Hydrogen can also be mixed into the natural gas pipeline network for storage and transportation. In addition, hydrogen and carbon dioxide can be combined, converted into methane and then input into the natural gas pipeline network.

[0006] Compared with the hydrogen energy development routes of technologically advanced countries such as Europe and Japan, my country's focus on hydrogen energy is still limited to hydrogen fuel cell vehicles, PtG and other hydrogen energy fields. Therefore, the development of hydrogen energy should have a longer-term vision and plan ahead for broader related fields.

[0007] Based on the high proportion of thermal power units in my country, thermal power units are more involved in peak load regulation and spot market transactions. In the future, the annual utilization hours of thermal power units will drop significantly. It will be difficult to adapt to the actual needs of my country's energy transformation and energy conservation and emission reduction by relying on simple power supply services. We should consider how to effectively utilize the existing thermal power assets. Integrated energy services and hydrogen energy utilization are both green carbon technologies that can reduce carbon emissions and are encouraged by the state. If we can use existing thermal power units and combine integrated energy services with hydrogen energy, it can not only solve the survival problem of thermal power plants, but also accelerate the realization of my country's energy transformation and carbon emission reduction goals. Summary of the invention

[0008] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a comprehensive energy service system for a thermal power plant combined with hydrogen energy application, which can realize the combination of comprehensive energy services and hydrogen energy.

[0009] To achieve the above-mentioned purpose, the comprehensive energy service system of a thermal power plant combined with hydrogen energy application described in the present invention includes a thermal power plant fuel system, a pulverizing system, a burner, an ammonia burner, a boiler, a steam turbine, a generator, a plant power grid, a public power grid, distributed photovoltaics, electrolytic hydrogen production equipment, an air separation equipment, an ammonia reactor, a public gas preparation equipment, an industrial steam equipment, a compression refrigeration equipment, an absorption refrigeration equipment, a compression heat pump and a heat exchanger;

[0010] The outlet of the fuel system of the thermal power plant is connected to the burner on the boiler through the pulverizing system in turn, the steam outlet of the boiler is connected to the inlet of the steam turbine, and the exhaust steam outlet of the steam turbine is connected to the industrial steam equipment, absorption refrigeration equipment and the heat release side of the heat exchanger;

[0011] The output end of the steam turbine is connected to the driving shaft of the generator, the output end of the generator is connected to the public power grid and the plant power grid, the plant power grid is connected to the electrolytic hydrogen production equipment, the air separation equipment, the public gas preparation equipment, the compression refrigeration equipment and the compression heat pump, the output end of the distributed photovoltaic is connected to the power interface of the electrolytic hydrogen production equipment, the hydrogen outlet of the electrolytic hydrogen production equipment and the nitrogen outlet of the air separation equipment are connected to the inlet of the ammonia reactor, and the outlet of the ammonia reactor is connected to the external transmission pipeline and the ammonia burner on the boiler;

[0012] It also includes cold storage equipment, and the outlet of the compression refrigeration equipment and the outlet of the absorption refrigeration equipment are connected to the cold storage equipment.

[0013] It also includes a heat storage device, and the outlet of the compression heat pump and the heat absorption side outlet of the heat exchanger are connected to the heat storage device.

[0014] It also includes a storage tank, the outlet of the ammonia reactor is connected to the inlet of the storage tank, and the outlet of the storage tank is connected to the external transmission pipeline and the ammonia burner on the boiler.

[0015] It also includes refrigeration equipment, and the outlet of the compression refrigeration equipment and the outlet of the absorption refrigeration equipment are connected to the refrigeration equipment.

[0016] It also includes heating equipment, and the outlet of the compression heat pump and the heat absorption side outlet of the heat exchanger are connected to the heating equipment.

[0017] The present invention has the following beneficial effects:

[0018] The comprehensive energy service system for thermal power plants combined with hydrogen energy application described in the present invention, in specific operation, utilizes the excess electricity of distributed photovoltaic and thermal power units for deep peak regulation to produce hydrogen, and the synthesized ammonia is stored and sent to the boiler for combustion when the unit is under high load, which not only realizes energy storage, improves the flexibility of the unit, and earns the price difference of electricity, but also reduces carbon emissions by burning with ammonia. In addition, the present invention synthesizes ammonia through the reaction of hydrogen and nitrogen, and the storage and transportation of ammonia are highly safe, with a low risk of deflagration, and the nitrogen is prepared from the air separation unit of the unit, with low cost. At the same time, in addition to power supply, the present invention can also provide heating, cooling, steam, public gas and energy storage. The electricity and gas used by the ammonia production system can come from the comprehensive energy service system, with lower cost, so as to realize the combination of comprehensive energy services and hydrogen energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the present invention.

[0020] Among them, 1 is the fuel system of the thermal power plant, 2 is the pulverizing system, 3 is the burner, 4 is the ammonia burner, 5 is the boiler, 6 is the steam turbine, 7 is the generator, 8 is the plant power grid, 9 is the public power grid, 10 is the distributed photovoltaic, 11 is the electrolytic hydrogen production equipment, 12 is the air separation equipment, 13 is the ammonia reactor, 14 is the storage tank, 15 is the public gas preparation equipment, 16 is the industrial steam equipment, 17 is the compression refrigeration equipment, 18 is the absorption refrigeration equipment, 19 is the compression heat pump, 20 is the heat exchanger, 21 is the cold storage equipment, 22 is the heat storage equipment, 23 is the cooling equipment, and 24 is the heating equipment. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only an embodiment of a part of the present invention, not all embodiments, and is not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concepts disclosed in the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present invention.

[0022] The accompanying drawings show schematic diagrams of structures according to embodiments disclosed in the present invention. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0023] refer to Figure 1 The comprehensive energy service system of a thermal power plant combined with hydrogen energy application described in the present invention comprises a thermal power plant fuel system 1, a pulverizing system 2, a burner 3, an ammonia burner 4, a boiler 5, a steam turbine 6, a generator 7, a plant power grid 8, a public power grid 9, a distributed photovoltaic 10, an electrolytic hydrogen production device 11, an air separation device 12, an ammonia reactor 13, a storage tank 14, a public gas preparation device 15, an industrial steam device 16, a compression refrigeration device 17, an absorption refrigeration device 18, a compression heat pump 19, a heat exchanger 20, a cold storage device 21, a heat storage device 22, a cooling device 23 and a heating device 24;

[0024] The outlet of the fuel system 1 of the thermal power plant is connected to the burner 3 on the boiler 5 through the pulverizing system 2 in sequence, the steam outlet of the boiler 5 is connected to the inlet of the steam turbine 6, and the exhaust steam outlet of the steam turbine 6 is connected to the industrial steam equipment 16, the absorption refrigeration equipment 18 and the heat release side of the heat exchanger 20;

[0025] The output end of the steam turbine 6 is connected to the driving shaft of the generator 7, the output end of the generator 7 is connected to the public power grid 9 and the plant power grid 8, the plant power grid 8 is connected to the electrolytic hydrogen production equipment 11, the air separation equipment 12, the public gas preparation equipment 15, the compression refrigeration equipment 17 and the compression heat pump 19, the output end of the distributed photovoltaic 10 is connected to the power interface of the electrolytic hydrogen production equipment 11, the hydrogen outlet of the electrolytic hydrogen production equipment 11 and the nitrogen outlet of the air separation equipment 12 are connected to the inlet of the ammonia reactor 13, the outlet of the ammonia reactor 13 is connected to the inlet of the storage tank 14, and the outlet of the storage tank 14 is connected to the external delivery pipeline and the ammonia burner 4 on the boiler 5;

[0026] The outlet of the compression refrigeration device 17 and the outlet of the absorption refrigeration device 18 are connected to the cold storage device 21 and the cold supply device 23, and the outlet of the compression heat pump 19 and the heat absorption side outlet of the heat exchanger 20 are connected to the heat storage device 22 and the heating device 24.

[0027] The input medium of the present invention is ammonia and coal, and the output medium is electricity, steam, cold medium, hot medium, hydrogen and nitrogen.

[0028] The specific working process of the present invention is:

[0029] The coal is transported to the burner 3 through the fuel system 1, the pulverizing system 2 and the primary air of the thermal power plant, and then enters the furnace of the boiler 5 for combustion.

[0030] The green electricity generated by the distributed photovoltaic 10 and the excess electricity from the deep peak regulation of the plant power grid 8 are supplied to the electrolytic hydrogen production equipment 11 to produce hydrogen. At the same time, the nitrogen produced by the air separation equipment 12 is led out and enters the ammonia reactor 13 together with the hydrogen produced by the electrolytic hydrogen production equipment 11. Ammonia is generated in the ammonia reactor 13 and enters the storage tank 14. The ammonia in the storage tank 14 can be sent out or sent to the boiler 5 for combustion. An ammonia burner 4 is added to the boiler 5. The ammonia in the storage tank 14 is mixed with the secondary air and then enters the boiler 5 for combustion through the ammonia burner 4.

[0031] A set of distributed photovoltaic 10 is arranged on the roof of the original thermal power plant or on the open space, and the electricity generated by the distributed photovoltaic 10 is used to produce ammonia, and the produced ammonia is stored in the storage tank 14 as energy storage. Ammonia has a fast combustion speed and can be directly burned in the furnace without being ground by the powder making system 2, so as to improve the load response rate of the unit to deep peak regulation, which is conducive to improving the winning rate in spot market transactions.

[0032] The coal and ammonia enter the boiler 5 through the burner 3 and the ammonia burner 4 respectively, and are burned, so that the chemical energy of the input fuel is converted into thermal energy, and the circulating working medium is heated to produce high-grade steam. The high-grade steam enters the steam turbine 6 to do work, and drives the generator 7 to generate electricity. After the work, the exhaust gas gradually reduces its grade to a specific grade, and is directly extracted from the steam turbine 6, and supplied to the industrial steam equipment 16, absorption refrigeration equipment 18 and heat exchanger 20 in the park through the pipeline network.

[0033] Part of the electric energy generated by the generator 7 enters the public power grid 9, and the other part enters the plant power grid 8. The electric energy is supplied to the air separation equipment 12, the electrolytic hydrogen production equipment 11 and the public gas preparation equipment 15 in the park through the plant power grid 8. Among them, part of the nitrogen produced by the air separation equipment 12 is used as plant gas, and the other part enters the ammonia reactor 13 to produce ammonia. The electricity of the electrolytic hydrogen production equipment 11 comes from the excess electricity of the deep peak regulation of the plant power grid 8 and the electricity generated by the distributed photovoltaic 10. Part of the hydrogen produced by the electrolytic hydrogen production equipment 11 is used for the plant, and part enters the ammonia reactor 13 to produce ammonia, so as to obtain various gas products such as nitrogen, oxygen, hydrogen and ammonia; it can also be supplied to the compression refrigeration equipment 17 and the compression heat pump 19 in the park.

[0034] The compression refrigeration equipment 17 and the absorption refrigeration equipment 18 can jointly produce cold medium, which is supplied to the cooling equipment 23 in the park through the pipeline network. The cold storage equipment 21 is set in the pipeline network as a buffer, and the balance of the cooling supply and cooling demand in the park is ensured by adjusting the cold medium flow distribution in the pipeline network in real time.

[0035] The compression heat pump 19 and the heat exchanger 20 can jointly produce heat medium. The heat medium is supplied to the heating equipment 24 in the park through the pipe network. The heat storage device 22 is set in the pipe network as a buffer, and the balance of heating supply and heating demand in the park is ensured by adjusting the heat medium flow distribution in the pipe network in real time.

[0036] It should be noted that, under the general background of thermal power plants suffering from losses, deep peak regulation and great pressure on carbon emissions, the present invention combines the comprehensive energy service system of thermal power plants with hydrogen energy applications, and builds distributed photovoltaic 10 on the vacant land of thermal power plants. In addition to power supply, it can also provide heat, steam, cooling, energy storage, hydrogen energy, ammonia combustion and other services, and supply a variety of products to improve the overall profitability of thermal power plants. Comprehensive energy services and hydrogen energy utilization, ammonia combustion can reduce its carbon emission level, and the excess electricity from distributed photovoltaic 10 power generation and deep peak regulation thermal power can be used for energy storage, water electrolysis to produce hydrogen, etc., thereby improving the deep peak regulation capability of the unit, the profitability of electricity price difference, and the hydrogen energy supply capability.

[0037] In addition, based on the original coal-fired units of the thermal power plant, the present invention takes the perspective of carbon emission reduction, improving the profitability of the thermal power plant and the comprehensive energy service level, and utilizes the electricity generated by the distributed photovoltaic 10 or the excess electricity during deep peak regulation of the thermal power unit to electrolyze water to produce hydrogen. Considering the high risk of hydrogen storage, hydrogen and nitrogen react to produce ammonia, and ammonia is used to realize hydrogen energy utilization. An ammonia burner 4 is added to the furnace, and ammonia enters the furnace for combustion. The excess ammonia is stored and can be delivered. The storage and transportation technology of ammonia is mature, and the explosion risk is much smaller than that of hydrogen. By utilizing the original coal-fired units in the thermal power plant, steam can be extracted from the steam turbine to achieve steam and heat supply, and steam can be used as the heat source of the absorption heat pump to achieve cooling. By taking advantage of the low cost of plant electricity, it can be used to power public gas production systems, such as air separation, to prepare public gas used in power plants or industrial parks. At the same time, the nitrogen produced can be used to react with hydrogen to produce ammonia. The excess electricity from the distributed photovoltaic 10 power generation and deep peak regulation can be used to electrolyze water to produce hydrogen, which then reacts with hydrogen to form ammonia to achieve ammonia energy storage.

Claims

1. A comprehensive energy service system for thermal power plants combined with hydrogen energy application, characterized in that: It includes a thermal power plant fuel system (1), a pulverizing system (2), a burner (3), an ammonia burner (4), a boiler (5), a steam turbine (6), a generator (7), a plant power grid (8), a public power grid (9), a distributed photovoltaic (10), an electrolytic hydrogen production device (11), an air separation device (12), an ammonia reactor (13), a public gas preparation device (15), an industrial steam device (16), a compression refrigeration device (17), an absorption refrigeration device (18), a compression heat pump (19) and a heat exchanger (20); The outlet of the fuel system (1) of the thermal power plant is connected to the burner (3) on the boiler (5) through the pulverizing system (2), the steam outlet of the boiler (5) is connected to the inlet of the steam turbine (6), and the exhaust steam outlet of the steam turbine (6) is connected to the industrial steam equipment (16), the absorption refrigeration equipment (18) and the heat release side of the heat exchanger (20); The output end of the steam turbine (6) is connected to the drive shaft of the generator (7), the output end of the generator (7) is connected to the public power grid (9) and the plant power grid (8), the plant power grid (8) is connected to the electrolytic hydrogen production equipment (11), the air separation equipment (12), the public gas preparation equipment (15), the compression refrigeration equipment (17) and the compression heat pump (19), the output end of the distributed photovoltaic (10) is connected to the power interface of the electrolytic hydrogen production equipment (11), the hydrogen outlet of the electrolytic hydrogen production equipment (11) and the nitrogen outlet of the air separation equipment (12) are connected to the inlet of the ammonia reactor (13), and the outlet of the ammonia reactor (13) is connected to the external transmission pipeline and the ammonia burner (4) on the boiler (5); It also includes a cold storage device (21), and the outlet of the compression refrigeration device (17) and the outlet of the absorption refrigeration device (18) are connected to the cold storage device (21); It also includes a heat storage device (22), and the outlet of the compression heat pump (19) and the heat absorption side outlet of the heat exchanger (20) are connected to the heat storage device (22); It also includes a storage tank (14), the outlet of the ammonia reactor (13) is connected to the inlet of the storage tank (14), and the outlet of the storage tank (14) is connected to the external delivery pipeline and the ammonia burner (4) on the boiler (5); It also includes a cooling device (23), wherein the outlet of the compression cooling device (17) and the outlet of the absorption cooling device (18) are connected to the cooling device (23); It also includes a heating device (24), and the outlet of the compression heat pump (19) and the heat absorption side outlet of the heat exchanger (20) are connected to the heating device (24).

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