Solar energy and biomass energy coupled combined heat and power generation system

Abstract

The utility model relates to a solar energy and biomass energy coupled combined heat and power generation system which comprises an air preheater, a biomass boiler, a PV / T, a solar vacuum tube collector, a first-stage organic Rankine cycle assembly, a second-stage organic Rankine cycle assembly and a jet type refrigeration cycle assembly. A fluid outlet of the PV / T is connected with a fluid inlet of the solar vacuum tube collector, a smoke outlet of the biomass boiler is connected with a hot fluid inlet of the air preheater, and a cold fluid outlet of the air preheater is connected with an air inlet of the biomass boiler. According to the utility model, by designing a two-stage organic Rankine cycle structure, solar energy and biomass energy are better coupled, and the stability of the system is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of energy and environment, in particular to a combined heat and power generation system coupling solar energy and biomass energy. Background Art

[0002] Considering the characteristics of global coverage and free availability of solar energy, and the fact that China has the largest biomass total in the world, and biomass energy can be directly stored and transported, it is very feasible to use the sustainability of biomass energy to alleviate the volatility of solar energy. The Solar Photovoltaic / thermal System (PV / T) has become one of the key research objects in the solar combined heat and power (CHP) system due to its photovoltaic and solar thermal integration technology. The main utilization ways of biomass energy include physical conversion, thermochemical conversion and biochemical conversion, among which biomass direct combustion power generation is the main technology for large-scale commercial application of biomass energy today. In addition, due to the low quality of the heat output by PV / T and the low energy density of biomass energy, the Organic Rankine Cycle (ORC) can be used to recover the low-quality heat energy of both, improving the energy utilization rate. In the prior art, in the multi-energy complementary application of solar energy and biomass energy, however, there is still room for improvement in the design principle of "temperature matching and energy cascade utilization" in the energy system, and the waste heat recovery device fails to effectively transfer the energy of biomass energy into the solar power generation cycle, improving the phenomenon of short operation time of ORC in the PV / T and ORC coupling system; In order to improve the comprehensive performance of ORC, many researchers have improved it based on the working principle of ORC, designing a regenerative organic Rankine cycle, a bleeding regenerative organic Rankine cycle, a reheat-bleeding regenerative-inner regenerative organic Rankine cycle and a dual organic Rankine cycle. In the improved ORC unit, due to the differences in working conditions, there may be more than one heat source, and the heat source temperature and energy density are both uncertain. Therefore, a detailed design of the energy system coupling the improved ORC unit is required. Summary of the Utility Model

[0003] The purpose of the utility model is to provide a combined heat and power generation system coupling solar energy and biomass energy, which can better couple solar energy and biomass energy by designing a two-stage organic Rankine cycle structure, improving the system stability.

[0004] To achieve the above object, the present utility model provides the following technical solutions: A cogeneration system coupling solar energy and biomass energy, the cogeneration system includes an air preheater, a biomass boiler, a PV / T, a solar vacuum tube collector, a first-stage organic Rankine cycle component, a second-stage organic Rankine cycle component, and a jet refrigeration cycle component. The fluid outlet of the PV / T is connected to the fluid inlet of the solar vacuum tube collector, the flue gas outlet of the biomass boiler is connected to the hot fluid inlet of the air preheater, and the cold fluid outlet of the air preheater is connected to the air inlet of the biomass boiler.

[0005] Further, the first-stage organic Rankine cycle component includes a first evaporator, a first turbine, a first condenser, and a first working fluid pump.

[0006] Further, the second-stage organic Rankine cycle component includes a preheater, a second evaporator, a second turbine, a second condenser, and a second working fluid pump.

[0007] Further, the jet refrigeration cycle component includes an ejector, a heat exchanger, a third evaporator, a third condenser, and a third working fluid pump.

[0008] Further, the fluid outlet of the solar vacuum tube collector is connected to the hot fluid inlet of the first evaporator through a first pipeline, the cold fluid outlet of the first evaporator is connected to the fluid inlet of the first turbine, the fluid outlet of the first turbine is connected to the hot fluid inlet of the first condenser, the hot fluid outlet of the first condenser is connected to the fluid inlet of the first working fluid pump through a second pipeline, the fluid outlet of the first working fluid pump is connected to the cold fluid inlet of the preheater, and the cold fluid outlet of the preheater is connected to the cold fluid inlet of the evaporator.

[0009] Further, the hot fluid outlet of the biomass boiler is connected to the hot fluid inlet of the second evaporator, the cold fluid outlet of the second evaporator is connected to the fluid inlet of the second turbine, the fluid outlet of the second turbine is connected to the hot fluid inlet of the preheater through a third pipeline, the hot fluid outlet of the preheater is connected to the hot fluid inlet of the second condenser through a fourth pipeline, the hot fluid outlet of the second condenser is connected to the fluid inlet of the second working fluid pump, and the fluid outlet of the second working fluid pump is connected to the cold fluid inlet of the second evaporator.

[0010] Further, the hot fluid outlet of the second evaporator is connected to the hot fluid inlet of the heat exchanger, the cold fluid outlet of the heat exchanger is connected to the fluid inlet of the ejector, the fluid outlet of the ejector is connected to the hot fluid inlet of the third condenser, the hot fluid outlet of the third condenser is respectively connected to the fluid inlets of the throttle valve and the third working fluid pump, the fluid outlet of the third working fluid pump is connected to the cold fluid inlet of the heat exchanger, the fluid outlet of the throttle valve is connected to the cold fluid inlet of the third evaporator, the cold fluid outlet of the third evaporator is connected to the fluid inlet of the ejector, the flue gas outlet of the biomass boiler is connected to the hot fluid inlet of the air preheater, and the cold fluid outlet of the air preheater is connected to the air inlet of the biomass boiler.

[0011] Further, a first valve is provided on the first pipeline, and the first valve controls the amount of hot water entering the evaporator from the solar vacuum tube collector.

[0012] Further, a second valve is provided on the second pipeline, and the second valve controls the working fluid flow rate entering the first evaporator from the first working fluid pump.

[0013] Further, a third valve is provided on the third pipeline, and the third valve controls the working fluid flow rate entering the preheater from the second turbine; a fourth valve is provided on the fourth pipeline, and the fourth valve controls the working fluid flow rate entering the second condenser from the second turbine.

[0014] Advantages of the present utility model:

[0015] (1) The present invention proposes an energy system based on the coupling of PV / T, solar vacuum tube collector, biomass boiler, organic Rankine cycle and ejector refrigeration cycle, achieving the effect of combined cooling, heating and power supply.

[0016] (2) The present invention designs a two-stage organic Rankine cycle structure, which better couples solar energy and biomass energy. The high-pressure fluid output by the first working fluid pump is preheated by the preheater, improving the operating stability of the first-stage organic Rankine cycle and the output heat. The system stability is improved. Description of the drawings

[0017] Figure 1 Schematic diagram of the system structure of the present invention.

[0018] Wherein: 1. Air preheater, 2. Biomass boiler, 3. PV / T, 4. Solar vacuum tube collector, 5. First valve, 6. First turbine, 7. First condenser, 8. Second valve, 9. First working fluid pump, 10. Preheater, 11. Second condenser, 12. Second working fluid pump, 13. First evaporator, 14. Third valve, 15. Fourth valve, 16. Second turbine, 17. Second evaporator, 18. Third working fluid pump, 19. Heat exchanger, 20. Throttle valve, 21. Third evaporator, 22. Injector, 23. Third condenser. Detailed implementation mode

[0019] The present invention will be further described below in conjunction with the accompanying drawings. (For better understanding, the orientation of the present invention is described according to the orientation shown in the drawings and should not be construed as a limitation on the present application; the following terms "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying relative importance.)

[0020] Please refer to Figure 1 , the present invention provides an embodiment: a solar and biomass energy coupled cogeneration system, the cogeneration system includes an air preheater 1, a biomass boiler 2, a PV / T 3, a solar vacuum tube collector 4, a first-stage organic Rankine cycle component, a second-stage organic Rankine cycle component and an ejector refrigeration cycle component, the fluid outlet of the PV / T 3 is connected to the fluid inlet of the solar vacuum tube collector 4, the flue gas outlet of the biomass boiler 2 is connected to the hot fluid inlet of the air preheater 1, and the cold fluid outlet of the air preheater 1 is connected to the air inlet of the biomass boiler 2. The two-stage organic Rankine cycle component structure is used to couple biomass energy and solar energy, and the waste heat of the biomass direct combustion and the second-stage organic Rankine cycle coupling system is input into the PV / T 3 and the first-stage organic Rankine cycle component coupling system to preheat the organic fluid entering the evaporator in the PV / T 3 and the first-stage organic Rankine cycle component coupling system, improving the operation stability and heat output of the first-stage organic Rankine cycle component; in addition, using the waste heat of the biomass boiler 2, an ejector refrigeration cycle is designed to achieve combined cooling, heating and power supply.

[0021] Please continue to refer to Figure 1 As shown, in an embodiment of the present invention, the first-stage organic Rankine cycle component includes a first evaporator 13, a first turbine 6, a first condenser 7 and a first working fluid pump 9.

[0022] Please continue to refer to Figure 1 As shown, in an embodiment of the present invention, the second-stage organic Rankine cycle component includes a preheater 10, a second evaporator 17, a second turbine 16, a second condenser 11 and a second working fluid pump 12.

[0023] Please continue to refer toFigure 1 As shown, in an embodiment of the present invention, the ejector refrigeration cycle assembly includes an ejector 22, a heat exchanger 19, a third evaporator 21, a third condenser 23, and a third working fluid pump 18.

[0024] Please continue to refer to Figure 1 As shown, in an embodiment of the present invention, the fluid outlet of the solar vacuum tube collector 4 is connected to the hot fluid inlet of the first evaporator 13 through a first pipeline, the cold fluid outlet of the first evaporator 13 is connected to the fluid inlet of the first turbine 6, the fluid outlet of the first turbine 6 is connected to the hot fluid inlet of the first condenser 7, the hot fluid outlet of the first condenser 7 is connected to the fluid inlet of the first working fluid pump 9 through a second pipeline, the fluid outlet of the first working fluid pump 9 is connected to the cold fluid inlet of the preheater 10, and the cold fluid outlet of the preheater 10 is connected to the cold fluid inlet of the evaporator. Water enters the back pipeline of the PV / T3 as the working medium to absorb the heat of the photovoltaic panel. The water working medium preheated by the PV / T3 flows to the solar vacuum tube collector 4 for secondary heating, and then enters the first evaporator 13 as the heat source to exchange heat with the organic working fluid of the first-stage organic Rankine cycle assembly, so that the organic working fluid becomes a high-temperature and high-pressure gas and expands to do work in the first turbine 6. The working fluid after expansion and work is condensed by the first condenser 7 and pressurized by the first working fluid pump 9, and then enters the first evaporator 13 again, thus forming the first-stage organic Rankine cycle. If the water after heat exchange in the first evaporator 13 is greater than 50 °C, it is used as domestic hot water.

[0025] Please continue to refer to Figure 1As shown, in an embodiment of the present invention, the hot fluid outlet of the biomass boiler 2 is connected to the hot fluid inlet of the second evaporator 17, the cold fluid outlet of the second evaporator 17 is connected to the fluid inlet of the second turbine 16, the fluid outlet of the second turbine 16 is connected to the hot fluid inlet of the preheater 10 through a third pipeline, the hot fluid outlet of the preheater 10 is connected to the hot fluid inlet of the second condenser 11 through a fourth pipeline, the hot fluid outlet of the second condenser 11 is connected to the fluid inlet of the second working fluid pump 12, and the fluid outlet of the second working fluid pump 12 is connected to the cold fluid inlet of the second evaporator 17. The biomass fuel and the air preheated by the air preheater 1 burn fully in the biomass boiler 2, and the heat is transferred to the cold water injected into the biomass boiler 2 to generate pressurized hot water. The pressurized hot water enters the second evaporator 17 to exchange heat with the organic working medium of the second-stage organic Rankine cycle assembly. If the pressurized hot water after heat exchange is greater than 50 °C, it is used as domestic hot water. The organic fluid at the outlet of the second evaporator 17 first passes through the pressurization of the second working fluid pump 12 and then absorbs heat in the second evaporator 17 to become a high-temperature and high-pressure organic fluid. This fluid enters the second turbine 16 and expands rapidly to drive the second turbine 16 to do work and generate electricity. The fluid after expansion still has residual heat, so it is designed to enter the preheater 10 to preheat the high-pressure organic fluid of the first-stage organic Rankine cycle assembly and reduce its own temperature to reduce the cooling water flow of the second condenser 11. The second condenser 11 condenses the working medium at the outlet of the preheater 10 into a liquid and sends it to the second working fluid pump 12 for pressurization. The pressurized organic working medium then enters the second evaporator 17 for evaporation, thus forming the second-stage organic Rankine cycle.

[0026] Please continue to refer to Figure 1As shown, in an embodiment of the present invention, the hot fluid outlet of the second evaporator 17 is connected to the hot fluid inlet of the heat exchanger 19. The cold fluid outlet of the heat exchanger 19 is connected to the fluid inlet of the ejector 22. The fluid outlet of the ejector 22 is connected to the hot fluid inlet of the third condenser 23. The hot fluid outlet of the third condenser 23 is respectively connected to the fluid inlets of the throttle valve 20 and the third working fluid pump 18. The fluid outlet of the third working fluid pump 18 is connected to the cold fluid inlet of the heat exchanger 19. The fluid outlet of the throttle valve 20 is connected to the cold fluid inlet of the third evaporator 21. The cold fluid outlet of the third evaporator 21 is connected to the fluid inlet of the ejector 22. The flue gas outlet of the biomass boiler 2 is connected to the hot fluid inlet of the air preheater 1. The cold fluid outlet of the air preheater 1 is connected to the air inlet of the biomass boiler 2. The working principle of the ejector refrigeration cycle assembly is as follows: The boiler pressurized hot water still has a relatively high temperature after releasing heat in the second evaporator 17. Therefore, it enters the heat exchanger 19 to heat the working fluid R600a of the ejector refrigeration cycle assembly. The heated R600a enters the ejector 22 and is fully mixed with the low-pressure gaseous working fluid ejected by the ejector 22, and then enters the third condenser 23 for condensation. A part of the condensed R600a is depressurized by the throttle valve 20 and enters the third evaporator 21 to absorb heat and refrigerate. After absorbing heat, the working fluid becomes a vapor state and enters the ejector 22. Another part is pressurized by the third working fluid pump 18 and then returns to the heat exchanger 19 for heating. Such a cycle is repeated to form an ejector refrigeration cycle. According to the characteristics of this combined cooling, heating and power supply system, PV / T3 operates when the solar radiation value is greater than 0; the first working fluid pump 9 and the first-stage organic Rankine cycle assembly operate simultaneously, that is, when the fluid temperature output by the solar vacuum tube collector 4 is greater than the lowest heat source temperature of the first-stage organic Rankine cycle assembly; the biomass boiler 2 operates all day long. When the first-stage organic Rankine cycle assembly starts to operate, the waste heat of the second turbine 16 preheats the fluid of the first-stage organic Rankine cycle assembly through the preheater 10. When the first-stage organic Rankine cycle assembly does not work, the waste heat of the second turbine 16 directly enters the second condenser 11 for condensation. The first turbine 6, the second turbine 16 and PV / T3 are the main power output components of this combined supply system.

[0027] Please continue to refer to Figure 1 As shown, in an embodiment of the present invention, a first valve 5 is provided on the first pipeline, and the first valve 5 controls the amount of hot water entering the evaporator from the solar vacuum tube collector 4.

[0028] Please continue to refer to Figure 1 As shown, in an embodiment of the present invention, a second valve 9 is provided on the second pipeline, and the second valve 9 controls the flow rate of the working fluid entering the first evaporator 13 from the first working fluid pump 9.

[0029] Please continue to refer toFigure 1 As shown, in an embodiment of the present invention, a No. 3 valve 14 is provided on the third pipeline, and the No. 3 valve 14 controls the working fluid flow rate entering the preheater 10 from the second turbine 16; a No. 4 valve 15 is provided on the fourth pipeline, and the No. 4 valve 15 controls the working fluid flow rate entering the second condenser 11 from the second turbine 16.

[0030] The working principle of the present utility model is as follows: According to the characteristics of the combined cooling, heating and power supply system, the biomass boiler, the second-stage organic Rankine cycle component and the ejector refrigeration cycle are started for all-weather operation; in actual use, a solar radiation sensor can be used for measurement. The solar radiation sensor can be directly installed on the bracket of the PV / T. When the solar radiation value is greater than 0, the PV / T and the solar vacuum tube collector operate, and when the fluid temperature output by the solar vacuum tube collector is greater than the lowest heat source temperature of the first-stage organic Rankine cycle component, the first-stage organic Rankine cycle component operates; when the first-stage organic Rankine cycle component starts to operate, the waste heat of the second turbine preheats the fluid of the first-stage organic Rankine cycle component through the preheater assembly, and when the first-stage organic Rankine cycle component does not work, the waste heat of the second turbine directly enters the second condenser for condensation.

[0031] The above are only the preferred embodiments of the present utility model, and should not be construed as limiting the present application. All equivalent changes and modifications made according to the scope of the patent application of the present utility model shall fall within the scope covered by the present utility model.

Claims

1. A cogeneration system coupling solar energy and biomass energy, characterized in that: The cogeneration system includes an air preheater, a biomass boiler, a PV / T, a solar vacuum tube collector, a first-stage organic Rankine cycle component, a second-stage organic Rankine cycle component, and a jet refrigeration cycle component. The fluid outlet of the PV / T is connected to the fluid inlet of the solar vacuum tube collector. The flue gas outlet of the biomass boiler is connected to the hot fluid inlet of the air preheater. The cold fluid outlet of the air preheater is connected to the air inlet of the biomass boiler.

2. The cogeneration system coupling solar energy and biomass energy according to claim 1, wherein: The first-stage organic Rankine cycle component includes a first evaporator, a first turbine, a first condenser, and a first working fluid pump.

3. The cogeneration system integrating solar energy and biomass energy according to claim 2, wherein: The second-stage organic Rankine cycle component includes a preheater, a second evaporator, a second turbine, a second condenser, and a second working fluid pump.

4. A cogeneration system coupling solar energy and biomass energy according to claim 3, characterized in that: The jet refrigeration cycle component includes an ejector, a heat exchanger, a third evaporator, a third condenser, and a third working fluid pump.

5. A cogeneration system coupling solar energy and biomass energy according to claim 2, characterized in that: The fluid outlet of the solar vacuum tube collector is connected to the hot fluid inlet of the first evaporator through a first pipeline. The cold fluid outlet of the first evaporator is connected to the fluid inlet of the first turbine. The fluid outlet of the first turbine is connected to the hot fluid inlet of the first condenser. The hot fluid outlet of the first condenser is connected to the fluid inlet of the first working fluid pump through a second pipeline. The fluid outlet of the first working fluid pump is connected to the cold fluid inlet of the preheater. The cold fluid outlet of the preheater is connected to the cold fluid inlet of the evaporator.

6. A cogeneration system integrating solar energy and biomass energy according to claim 3, characterized in that: The hot fluid outlet of the biomass boiler is connected to the hot fluid inlet of the second evaporator. The cold fluid outlet of the second evaporator is connected to the fluid inlet of the second turbine. The fluid outlet of the second turbine is connected to the hot fluid inlet of the preheater through a third pipeline. The hot fluid outlet of the preheater is connected to the hot fluid inlet of the second condenser through a fourth pipeline. The hot fluid outlet of the second condenser is connected to the fluid inlet of the second working fluid pump. The fluid outlet of the second working fluid pump is connected to the cold fluid inlet of the second evaporator.

7. A cogeneration system coupling solar energy and biomass energy according to claim 4, characterized in that: The hot fluid outlet of the second evaporator is connected to the hot fluid inlet of the heat exchanger. The cold fluid outlet of the heat exchanger is connected to the fluid inlet of the ejector. The fluid outlet of the ejector is connected to the hot fluid inlet of the third condenser. The hot fluid outlet of the third condenser is connected to the fluid inlets of a throttle valve and the third working fluid pump respectively. The fluid outlet of the third working fluid pump is connected to the cold fluid inlet of the heat exchanger. The fluid outlet of the throttle valve is connected to the cold fluid inlet of the third evaporator. The cold fluid outlet of the third evaporator is connected to the fluid inlet of the ejector. The flue gas outlet of the biomass boiler is connected to the hot fluid inlet of the air preheater. The cold fluid outlet of the air preheater is connected to the air inlet of the biomass boiler.

8. A cogeneration system coupling solar energy and biomass energy according to claim 5, characterized in that: A first valve is provided on the first pipeline, and the first valve controls the amount of hot water entering the evaporator from the solar vacuum tube collector.

9. A cogeneration system integrating solar energy and biomass energy according to claim 5, characterized in that: A second valve is provided on the second pipeline, and the second valve controls the flow rate of the working fluid entering the first evaporator from the first working fluid pump.

10. A cogeneration system coupling solar energy and biomass energy according to claim 6, characterized in that: A three-way valve is provided on the third pipeline, and the three-way valve controls the working fluid flow rate entering the preheater from the second turbine; a four-way valve is provided on the fourth pipeline, and the four-way valve controls the working fluid flow rate entering the second condenser from the second turbine.

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