Combined heat and power generation unit and peak shaving device of combined heat and power generation unit

Abstract

The combined heat and power generation unit comprises a high-pressure cylinder, an intermediate-pressure cylinder, a low-pressure cylinder and a boiler, the intermediate-pressure cylinder and the low-pressure cylinder are each provided with a drainage pipeline, the low-pressure cylinder is provided with a steam outlet end, the steam outlet end is connected with a condenser, the condenser is provided with a hot well, and the hot well and the drainage pipelines are each connected with a first power pump; the output ends of the two first power pumps are connected with the input end of the boiler.

Description

Technical Field

[0001] The present invention belongs to the technical field of cogeneration, and particularly relates to a cogeneration unit and a peak shaving device for a cogeneration unit. Background Art

[0002] When a cogeneration unit operates in a heat-determined power mode, it is necessary to give priority to meeting the heat load demand, resulting in rigid power generation output and difficulty in adapting to the peak shaving requirements of the power grid; there are still some problems with traditional peak shaving technologies; during low load periods of the power grid (such as at night), the unit adjusts the peak by reducing the output or shutting down, but the waste heat of the boiler flue gas, the drain water of the steam turbine, and the low-temperature waste heat (40 - 80 °C) in the hot well of the condenser are difficult to recover and utilize, and direct discharge causes energy waste; at the same time, the response speed of the unit restarting or increasing the load is slow and cannot match the rapid peak shaving demand of the power grid; therefore, a cogeneration unit and a peak shaving device for a cogeneration unit are provided to solve the above problems. Summary of the Invention

[0003] The purpose of the present invention is to provide a cogeneration unit and a peak shaving device for a cogeneration unit to solve the problems existing in the background art.

[0004] To achieve the above technical purpose, the technical solution adopted by the present invention is as follows:

[0005] A cogeneration unit includes a high-pressure cylinder, an intermediate-pressure cylinder, a low-pressure cylinder, and a boiler. The intermediate-pressure cylinder and the low-pressure cylinder are both equipped with drain pipes. The low-pressure cylinder has an exhaust end, and the exhaust end is connected to a condenser. The condenser is equipped with a hot well. The hot well and the drain pipes are both connected to a first power pump. The output ends of the two first power pumps are both connected to the input end of the boiler.

[0006] Preferably, the input ends of the two first power pumps are both equipped with first valves.

[0007] A peak shaving device for a cogeneration unit includes a heat-insulated water storage tank. The input end of the heat-insulated water storage tank is connected to the output ends of the two first power pumps. The output end of the heat-insulated water storage tank is connected to an axial flow water turbine. The axial flow water turbine is equipped with a generator. The bottom height of the heat-insulated water storage tank is higher than that of the axial flow water turbine. The output end of the axial flow water turbine is connected to the input end of the boiler;

[0008] A number of heat absorption components are assembled inside the heat-insulated water storage tank. The heat absorption components include stainless steel balls. A number of hexagonal honeycomb chambers are assembled inside the stainless steel balls. Paraffin is filled inside the hexagonal honeycomb chambers. A number of the stainless steel balls are stacked at the bottom of the heat-insulated water storage tank through a woven mesh.

[0009] Preferably, the number of the heat preservation and storage water tanks is three, the height difference between the heat preservation and storage water tank and the axial flow water turbine below it is 3 - 5 m, a second valve is assembled at the input end of the axial flow water turbine, and a second power pump and a third valve are assembled between adjacent heat preservation and storage water tanks.

[0010] Preferably, the hexagonal honeycomb chambers are made of phenyl silicone rubber, the wall thickness of the hexagonal honeycomb chambers is 0.5 - 1 mm, the side length of the hexagonal honeycomb chambers is 3 - 5 mm, the diameter of the stainless steel balls is 40 - 60 mm, and the shell thickness of the stainless steel balls is 1.5 - 2 mm.

[0011] Preferably, stainless steel microfibers are embedded in the side walls of the hexagonal honeycomb chambers.

[0012] Preferably, inert gas is reserved and filled in the internal spaces of a plurality of the hexagonal honeycomb chambers.

[0013] Preferably, the spaces between the outermost hexagonal honeycomb chambers and the stainless steel balls are filled with silicone potting glue.

[0014] Preferably, the stacking manner of the hexagonal honeycomb chambers is staggered stacking.

[0015] Advantages of the present invention:

[0016] 1. The heat preservation and storage water tank and the water turbine convert the redundant heat energy / electric energy during the low - valley period into potential energy and heat energy for storage, and release power generation during the peak period, significantly improving the peak - shaving capacity of the unit. The combination of paraffin - phase - change heat storage and hydro - power generation realizes multi - level energy conversion of heat - electricity - heat, and improves the comprehensive energy utilization rate.

[0017] 2. The stepped design of the three heat preservation and storage water tanks, in cooperation with the power pump / valve, supports a multi - level energy - release strategy to adapt to different load requirements; the bottom of the heat preservation and storage water tank is higher than the water turbine, generating electricity using gravitational potential energy, reducing additional energy consumption; waste - heat recovery reduces the fuel consumption of the boiler, reducing carbon emissions; the closed - loop water circulation saves water resources; the benefits of peak - shaving power generation are superimposed with the reuse of heat energy, shortening the investment payback period. Brief Description of the Drawings

[0018] The present invention can be further illustrated by the non - restrictive embodiments given in the drawings.

[0019] Figure 1 is a schematic diagram of a cogeneration unit and a peak - shaving device for a cogeneration unit of the present invention;

[0020] Figure 2 is a schematic diagram of the structure of the stainless steel balls in the present invention.

[0021] The main component symbols are explained as follows:

[0022] High-pressure cylinder 1, intermediate-pressure cylinder 11, low-pressure cylinder 12, steam outlet end 121, boiler 13, drain pipe 14, condenser 141, hot well 142, first power pump 143, first valve 144, heat preservation storage water tank 15, axial flow water turbine 151, generator 152, second valve 153, second power pump 154, third valve 155, stainless steel ball 16, hexagonal honeycomb chamber 161. Detailed implementation mode

[0023] In order to enable those skilled in the art to better understand the present invention, the technical solution of the present invention will be further described below in conjunction with the drawings and embodiments.

[0024] As Figure 1 shown, a cogeneration unit of the present invention includes a high-pressure cylinder 1, an intermediate-pressure cylinder 11, a low-pressure cylinder 12 and a boiler 13. The intermediate-pressure cylinder 11 and the low-pressure cylinder 12 are both equipped with drain pipes 14. The low-pressure cylinder 12 is provided with a steam outlet end 121. The steam outlet end 121 is connected to a condenser 141. The condenser 141 is equipped with a hot well 142. Both the hot well 142 and the drain pipe 14 are connected to a first power pump 143. The output ends of the two first power pumps 143 are connected to the input end of the boiler 13, and the input ends of the two first power pumps 143 are both equipped with first valves 144.

[0025] A peak shaving device for a cogeneration unit includes a heat preservation storage water tank 15. The input end of the heat preservation storage water tank 15 is connected to the output ends of the two first power pumps 143. The output end of the heat preservation storage water tank 15 is connected to an axial flow water turbine 151. The axial flow water turbine 151 is equipped with a generator 152. The bottom height of the heat preservation storage water tank 15 is higher than that of the axial flow water turbine 151. The output end of the axial flow water turbine 151 is connected to the input end of the boiler 13;

[0026] The number of the heat preservation storage water tanks 15 is three. The height difference between the heat preservation storage water tank 15 and the axial flow water turbine 151 below it is 3-5 m. The input end of the axial flow water turbine 151 is equipped with a second valve 153. Second power pumps 154 and third valves 155 are assembled between adjacent heat preservation storage water tanks 15;

[0027] As Figure 2 shown, a number of heat absorption components are assembled inside the heat preservation storage water tank 15. The heat absorption components include stainless steel balls 16. A number of hexagonal honeycomb chambers 161 are assembled inside the stainless steel balls 16. The space between the outermost hexagonal honeycomb chambers 161 and the stainless steel balls 16 is filled with silicone potting glue; Paraffin is filled inside the hexagonal honeycomb chambers 161. The internal partition of the stainless steel ball 16 into a number of hexagonal honeycomb chambers 161 can reduce the single-chamber expansion pressure; A number of stainless steel balls 16 are stacked at the bottom of the heat preservation storage water tank 15 through a woven net;

[0028] The hexagonal honeycomb cell 161 is made of phenyl silicone rubber, the wall thickness of the hexagonal honeycomb cell 161 is 0.5-1 mm, the side length of the hexagonal honeycomb cell 161 is 3-5 mm, the diameter of the stainless steel ball 16 is 40-60 mm, and the shell thickness of the stainless steel ball 16 is 1.5-2 mm;

[0029] Stainless steel microfibers are embedded in the side walls of the hexagonal honeycomb cells 161 to form a heat conduction network and improve the overall thermal conductivity;

[0030] Space is reserved inside a number of hexagonal honeycomb cells for filling with inert gas. A small amount of inert gas can absorb part of the expansion pressure through gas compression.

[0031] The stacking method of the hexagonal honeycomb cells 161 is staggered stacking, which can improve the fatigue resistance of the structure;

[0032] During the low-load period of the power grid (such as at night), the excess steam condensate generated by the cogeneration unit (from the hot well 142 and the drain pipe 14) is transported to the thermal insulation water storage tank 15 for storage through the first power pump 143, rather than directly returning to the boiler 13; after the condensate flows into the thermal insulation water storage tank 15, the paraffin in the stainless steel ball 16 absorbs the waste heat in the water through phase change, and stores the heat energy in the form of latent heat; and the water is transferred between adjacent thermal insulation water storage tanks 15 through the second power pump 154 ​​and the third valve 155, forming a stepped energy storage and optimizing the potential energy utilization;

[0033] When the grid load reaches its peak, the second valve 153 is opened, and the water in the thermal insulation water storage tank 15 drives the axial flow turbine 151 to generate electricity under the action of gravity. The electric energy is fed into the grid through the generator 152 to achieve peak load regulation. During the water release process, the paraffin solidifies and releases the stored heat, preheating the water flowing through the water storage tank 15 and reducing the heating energy consumption of the boiler 13.

[0034] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A cogeneration unit, comprising a high pressure cylinder, a medium pressure cylinder, a low pressure cylinder and a boiler, characterized in that: The medium-pressure cylinder and the low-pressure cylinder are both equipped with drain pipes, the low-pressure cylinder is provided with a steam outlet, the steam outlet is connected to a condenser, the condenser is equipped with a hot well, the hot well and the drain pipe are both connected to a first power pump, and the two output ends of the first power pumps are both connected to the boiler input end.

2. A cogeneration unit according to claim 1, characterized in that: The two first power pump input ends are each equipped with a first valve.

3. A peak load regulation device for a combined heat and power unit, based on a combined heat and power unit according to claim 1-2, characterized in that: It comprises a heat preservation water storage tank, the input end of the heat preservation water storage tank is connected to the output ends of the two first power pumps, the output end of the heat preservation water storage tank is connected to an axial flow turbine, the axial flow turbine is equipped with a generator, the bottom height of the heat preservation water storage tank is higher than the axial flow turbine, and the output end of the axial flow turbine is connected to the input end of the boiler; The thermal insulation water storage tank is internally equipped with a plurality of heat absorption components, the heat absorption components include stainless steel balls, the stainless steel balls are internally equipped with a plurality of hexagonal honeycomb cells, the interior of the hexagonal honeycomb cells is filled with paraffin, and the plurality of stainless steel balls are stacked and placed at the bottom of the thermal insulation water storage tank through a woven mesh.

4. A peak load regulation device for a combined heat and power unit according to claim 3, characterized in that: There are three thermal insulation water storage tanks, and the height difference between the thermal insulation water storage tank and the axial flow turbine below it is 3-5m. The input end of the axial flow turbine is equipped with a second valve, and the second power pump and the third valve are installed between adjacent thermal insulation water storage tanks.

5. A peak load regulation device for a combined heat and power unit according to claim 4, characterized in that: The hexagonal honeycomb cell is made of phenyl silicone rubber, the wall thickness of the hexagonal honeycomb cell is 0.5-1mm, the side length of the hexagonal honeycomb cell is 3-5mm, the diameter of the stainless steel ball is 40-60mm, and the shell thickness of the stainless steel ball is 1.5-2mm.

6. A peak load regulation device for a combined heat and power unit according to claim 5, characterized in that: Stainless steel microfibers are embedded in the side walls of the hexagonal honeycomb cells.

7. A peak load regulation device for a combined heat and power unit according to claim 6, characterized in that: Space is reserved inside a plurality of the hexagonal honeycomb cells for filling with inert gas.

8. A peak load regulation device for a combined heat and power unit according to claim 7, characterized in that: The space between the hexagonal honeycomb cells at the outermost edges and the stainless steel balls is filled with silicone potting glue.

9. A peak load regulation device for a combined heat and power unit according to claim 8, characterized in that: The stacking mode of the hexagonal honeycomb cells is staggered stacking.

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