Organic Rankine cycle power generation system based on waste heat recovery of internal combustion engine
Through the use of hot water or thermal conductivity as the heat transfer medium in the internal combustion engine's flue gas heat recovery system, the problem of organic work quality is solved at high temperature, and the power generation efficiency and energy utilization rate of internal combustion engines are improved.
Patent Information
- Application Number
- CN202421301857.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-07
- Publication Date
- 2025-01-28
- Estimated Expiration
- 2034-06-07
AI Technical Summary
When the waste heat of an internal combustion engine is used, the prior art has the problem of decomposing organic working fluid at high temperatures, resulting in low power generation efficiency.
By using hot water or heat conductive oil as the heat transfer medium in the smoke heat recovery system of the internal combustion engine, the heat of the flue gas is transmitted to the organic working quality to avoid directly heating the evaporator, thereby controlling the temperature of the organic quality and preventing decomposition.
It improves the comprehensive power generation efficiency of internal combustion engines, achieves efficient energy use of energy, reduces the emissions of pollutants, and maintains a stable operation of the system.
Smart Images
Figure CN222414968U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of power generation, in particular to an organic Rankine cycle power generation system based on waste heat recovery of an internal combustion engine. Background Art
[0002] At present, from the perspective of the energy balance of internal combustion engines, the output effective power generally only accounts for 30%-45% of the total input combustion heat. Except for less than 10% used to overcome power losses such as friction, the remaining waste heat energy is mainly discharged into the atmosphere through exhaust (300-500℃) and cooling medium (high-temperature cylinder jacket water (80-90℃), medium-temperature cooling water (30-40℃)), etc.). The total amount of medium and low temperature waste heat resources discharged by the above-mentioned internal combustion engines is huge and widely available. Therefore, it is very necessary to reasonably and effectively utilize this part of medium and low temperature waste heat recovery resources.
[0003] Organic Rankine cycle can recycle and utilize medium and low temperature waste heat resources to generate electricity, converting low-grade heat energy into high-grade electricity. It is an effective technical path to recycle medium and low temperature waste heat resources. Therefore, using organic Rankine cycle power generation technology to efficiently convert and reuse the waste heat energy of internal combustion engines is an effective way to improve energy efficiency, save energy and reduce pollutant emissions.
[0004] CN217873048U discloses a waste heat utilization system for an internal combustion engine, which uses the waste heat of the internal combustion engine exhaust gas and the waste heat of the cylinder liner to heat the preheater and evaporator in the ORC organic Rankine cycle power generation system respectively. Although waste heat utilization is achieved, the use of exhaust gas (300-500°C) to directly heat the organic working fluid in the evaporator will cause the organic working fluid to decompose. Utility Model Content
[0005] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model proposes an organic Rankine cycle power generation system based on waste heat recovery of an internal combustion engine, which can recycle waste heat resources emitted by the internal combustion engine, convert medium and low temperature waste heat resources into high-quality electrical energy, and improve the comprehensive power generation efficiency of the internal combustion engine by more than 5%.
[0006] According to an embodiment of the utility model, an organic Rankine cycle power generation system based on internal combustion engine waste heat recovery includes a water waste heat recovery system, a water cooling system, a flue gas waste heat recovery system, and a power generation system. The water waste heat recovery system is connected in parallel with the water cooling system; the water waste heat recovery system is connected in series with the internal combustion engine flue gas waste heat recovery system; and the waste heat recovery system is connected to the power generation system.
[0007] An organic Rankine cycle power generation system based on internal combustion engine waste heat recovery according to an embodiment of the utility model has at least the following beneficial effects:
[0008] The waste heat of the flue gas and high-temperature cylinder water of the internal combustion engine is used to generate electricity, which improves energy utilization and achieves energy conservation and emission reduction; the flue gas transfers heat to hot water or heat transfer oil, which in turn heats the organic working fluid. By controlling the temperature of the hot water or heat transfer oil, the decomposition of the organic working fluid is avoided; and the original water cooling system is retained. When the flue gas waste heat recovery system or the power generation system needs to be repaired, it will not affect the operation of the internal combustion engine.
[0009] According to some embodiments of the utility model, the water waste heat recovery system includes an internal combustion engine, a high-temperature cylinder jacket water pump, a first electric three-way valve, a second electric three-way valve, a high-temperature cylinder jacket water radiator and a plate heat exchanger;
[0010] The high-temperature cylinder jacket water pump inputs the high-temperature cylinder jacket water in the internal combustion engine into the first electric three-way valve, and the high-temperature cylinder jacket water flows back to the internal combustion engine after passing through the first electric three-way valve, the second electric three-way valve and the high-temperature cylinder jacket water radiator, so that the heat energy in the high-temperature cylinder jacket water can be effectively recovered and utilized, thereby improving the energy utilization efficiency of the system.
[0011] According to some embodiments of the utility model, the heat release side of the plate heat exchanger is connected in parallel between the first electric three-way valve and the second electric three-way valve to meet the needs of different working conditions. In this way, the system can adjust the flow rate of the heat release side of the plate heat exchanger as needed to maintain stable operation and optimal performance of the system.
[0012] According to some embodiments of the utility model, the flue gas waste heat recovery system includes a denitration device, a waste heat boiler, a chimney, an oil pump and an evaporator; the flue gas of the internal combustion engine passes through the denitration device and the waste heat boiler and is discharged from the chimney. These components work together to recover heat energy from the flue gas generated by the internal combustion engine and maximize the use of the heat energy generated by the internal combustion engine.
[0013] According to some embodiments of the utility model, after the heat transfer medium flows out of the waste heat boiler, it flows through the heat release side of the evaporator, the oil pump, the heat absorption side of the plate heat exchanger, and the heat absorption side of the waste heat boiler in sequence. In this process, the heat transfer medium is heated and the waste heat is transferred to the heat transfer medium. After this step, the heat transfer medium is pumped out again by the oil pump and circulates to other parts of the system. Through the operation of the oil pump, the system can effectively utilize the waste heat.
[0014] According to some embodiments of the utility model, the power generation system includes an evaporator, an expander, a generator, a condenser, a working fluid pump, a cooling water pump and a cooling tower;
[0015] The heat source flows into the inlet of the working fluid pump through the heat absorption side of the evaporator, the inlet of the expander and the heat release side of the condenser, and then flows back to the evaporator through the working fluid pump to complete the organic Rankine cycle.
[0016] Through processes such as evaporation, expansion, condensation and pumping, the thermal energy of the heat source is converted into electrical energy, and the continuous conversion of energy is achieved through the circulation of the working fluid. The thermal energy can be efficiently utilized and converted into electrical energy, thus realizing the effective use of energy.
[0017] According to some embodiments of the utility model, the driving shaft of the generator is connected to the output shaft of the expander, and the output end of the generator is connected to the power grid, which simplifies the system structure and improves the efficiency of energy conversion.
[0018] According to some embodiments of the utility model, the cooling water pump draws cooling water from the cooling tower, and the cooling water flows through the condenser and then flows back to the cooling tower, thereby ensuring the circulation of cooling water between the condenser and the cooling tower, and effectively transferring the heat in the condenser to the cooling water, so that it cools the working fluid liquid.
[0019] According to some embodiments of the present invention, the heat transfer medium is hot water or heat transfer oil.
[0020] Hot water has the characteristics of large heat capacity and good stability. By heating the water during the heat release process of the heat source, hot water can take away a large amount of heat energy and convert it into electrical energy in the waste heat power generation system. Thermal oil has good thermal stability and heat transfer performance. During the heat release process of the heat source, thermal oil can effectively absorb heat energy and transfer it to the waste heat power generation system for energy conversion. By selecting a suitable heat transfer medium, the energy conversion efficiency and stability of the system can be improved, thereby better realizing the operation and performance optimization of the power generation system.
[0021] According to some embodiments of the utility model, the heat transfer medium and working medium used in the organic Rankine cycle are organic working fluids, which are a special type of working fluids, usually organic compounds, with a low boiling point and good steam properties. They can evaporate at low temperatures and are suitable for low-temperature thermal energy conversion.
[0022] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:
[0024] Figure 1 This is a structural schematic diagram of an organic Rankine cycle power generation system based on internal combustion engine waste heat recovery.
[0025] Figure numerals: 1. internal combustion engine; 2. high-temperature cylinder jacket water pump; 3. high-temperature cylinder jacket water radiator; 4. plate heat exchanger; 5. first electric three-way valve; 6. second electric three-way valve; 7. denitrification device; 8. oil pump; 9. waste heat boiler; 10. chimney; 11. evaporator; 12. expander; 13. generator; 14. condenser; 15. working fluid pump; 16. cooling water pump; 17. cooling tower. DETAILED DESCRIPTION
[0026] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.
[0027] In the description of the present invention, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0028] In the description of the present utility model, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.
[0029] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.
[0030] Reference Figure 1 An organic Rankine cycle power generation system based on internal combustion engine waste heat recovery includes a water waste heat recovery system, a water cooling system, a flue gas waste heat recovery system, and a power generation system. The water waste heat recovery system is connected in parallel with the water cooling system; the water waste heat recovery system is connected in series with the flue gas waste heat recovery system; and the waste heat recovery system is connected to the power generation system.
[0031] The system utilizes the waste heat of the flue gas and the waste heat of the high-temperature cylinder jacket water of the internal combustion engine 1 to generate electricity, thereby improving energy utilization and achieving energy conservation and emission reduction; the flue gas transfers heat to hot water or heat transfer oil, which in turn heats the organic working fluid, and by controlling the temperature of the hot water or heat transfer oil, the decomposition of the organic working fluid is avoided; and the original water cooling system is retained, so when the flue gas waste heat recovery system or the power generation system needs to be repaired, it will not affect the operation of the internal combustion engine 1.
[0032] Further, the water waste heat recovery system includes an internal combustion engine 1, a high-temperature cylinder jacket water pump 2, a first electric three-way valve 5, a second electric three-way valve 6, a high-temperature cylinder jacket water radiator 3 and a plate heat exchanger 4;
[0033] Among them, the high-temperature cylinder jacket water is pumped out of the internal combustion engine 1 through the high-temperature cylinder jacket water pump 2, and the flow direction is controlled by the first electric three-way valve 5, and then enters the high-temperature cylinder jacket water radiator 3 through the second electric three-way valve 6. In the high-temperature cylinder jacket water radiator 3, the heat of the water is dissipated to the surrounding medium. Then, the high-temperature cylinder jacket water flows through the plate heat exchanger 4 and exchanges heat with other media to effectively utilize the waste heat. Finally, the water after heat exchange is sent back to the internal combustion engine 1 and circulates to form a closed waste heat recovery system, so that the heat energy in the high-temperature cylinder jacket water can be effectively recovered and utilized, thereby improving the energy utilization efficiency of the system.
[0034] Preferably, the heat release side of the plate heat exchanger 4 is connected in parallel between the first electric three-way valve 5 and the second electric three-way valve 6 to meet the needs of different working conditions. In this way, the system can adjust the flow rate of the heat release side of the plate heat exchanger 4 as needed to maintain stable operation and optimal performance of the system.
[0035] Specifically, the flue gas waste heat recovery system includes a denitration device 7, a waste heat boiler 9, a chimney 10, an oil pump 8 and an evaporator 11; the flue gas generated by the internal combustion engine 1 first passes through the denitration device 7 to remove harmful substances such as sulfides, and then enters the waste heat boiler 9. In the waste heat boiler 9, the waste heat in the flue gas is used to heat water or other media to generate steam or hot water, etc., and then the flue gas treated by the waste heat boiler 9 is discharged through the chimney 10.
[0036] In this embodiment, after flowing out of the waste heat boiler 9 , the heat transfer medium flows through the heat release side of the evaporator 11 , the oil pump 8 , the heat absorption side of the plate heat exchanger 4 , and the heat absorption side of the waste heat boiler 9 in sequence.
[0037] Specifically, the heat transfer medium first flows through the heat release side of the evaporator 11, where the heat transfer medium releases heat, causing the medium in the evaporator 11 to evaporate, thereby achieving the purpose of heat transfer. Then, the oil pump 8 extracts the heat transfer medium out of the evaporator 11 and transports it to the next destination. Next, the heat transfer medium flows through the oil pump 8, during which the oil pump 8 increases the pressure of the heat transfer medium or promotes its flow. Subsequently, the heat transfer medium enters the heat absorption side of the plate heat exchanger 4, exchanges heat with other media, and absorbs heat. Finally, the heat transfer medium enters the heat absorption side of the waste heat boiler 9. Here, the heat transfer medium absorbs the waste heat from the flue gas generated by the internal combustion engine 1 on the heat absorption side of the waste heat boiler 9. In this process, the heat transfer medium is heated and the waste heat is transferred to the heat transfer medium. After this step, the heat transfer medium is extracted again by the oil pump 8 and circulates to other parts of the system.
[0038] Furthermore, the power generation system includes an evaporator 11, an expander 12, a generator 13, a condenser 14, a working fluid pump 15, a cooling water pump 16 and a cooling tower 17; the heat source flows into the inlet of the working fluid pump 15 after passing through the heat absorption side of the evaporator 11, the inlet of the expander 12 and the heat release side of the condenser 14, and then flows back to the evaporator 11 through the working fluid pump 15 to complete the organic Rankine cycle.
[0039] Specifically, the heat energy released by the heat source first enters the system through the heat absorption side of the evaporator 11, causing the working fluid to evaporate. The evaporated working fluid passes through the expander 12, and its inlet receives heat energy input, causing the working fluid to expand and drive the expander 12. This process releases mechanical energy, driving the first generator 13 to generate electrical energy. Subsequently, the working fluid flows from the outlet of the expander 12 to the condenser 14, releases heat energy and becomes liquid. In this process, the heat energy is converted into the heat energy of the cooling medium of the condenser 14. Next, the liquid working fluid is pumped back to the evaporator 11, and this cycle completes the organic Rankine cycle. The working fluid pump 15 is responsible for returning the working fluid flowing out of the heat release side of the condenser 14 to the evaporator 11 to keep the cycle going.
[0040] Through processes such as evaporation, expansion, condensation and pumping, the thermal energy of the heat source is converted into electrical energy, and the continuous conversion of energy is achieved through the circulation of the working fluid. The thermal energy can be efficiently utilized and converted into electrical energy, thus realizing the effective use of energy.
[0041] Preferably, the drive shaft of the generator 13 is connected to the output shaft of the expander 12, and the output end of the generator 13 is connected to the power grid, which simplifies the system structure and improves the efficiency of energy conversion. Since the expander 12 and the generator 13 are directly connected, the energy loss in the energy transfer process is reduced, thereby improving the overall efficiency of the system. At the same time, by connecting the output of the generator 13 to the power grid, the generated electric energy can be directly input into the power grid, providing users with a reliable power supply.
[0042] Furthermore, the cooling water pump 16 pumps the cooling water out of the cooling tower 17, and the cooling water flows through the condenser 14 and then flows back to the cooling tower 17, ensuring the circulation of the cooling water between the condenser 14 and the cooling tower 17, effectively transferring the heat in the condenser 14 to the cooling water, so that it cools the working fluid.
[0043] In this embodiment, the heat transfer medium is hot water. Hot water has the characteristics of large heat capacity and good stability. By heating the water during the heat release process of the heat source, the hot water can take away a large amount of heat energy and convert it into electrical energy in the waste heat power generation system.
[0044] In one embodiment, the heat transfer medium is thermal oil. Thermal oil has good thermal stability and heat transfer performance. During the heat release process of the heat source, the thermal oil can effectively absorb heat energy and transfer it to the waste heat power generation system for energy conversion. By selecting a suitable heat transfer medium, the energy conversion efficiency and stability of the system can be improved, thereby better realizing the operation and performance optimization of the power generation system.
[0045] Preferably, the heat transfer medium and working medium used in the organic Rankine cycle are organic working fluids, which are a special type of working fluids, usually organic compounds, with a low boiling point and good steam properties. They can evaporate at low temperatures and are suitable for low-temperature thermal energy conversion.
[0046] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.
[0047] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.
Claims
1. An organic Rankine cycle power generation system based on waste heat recovery from an internal combustion engine, characterized in that: Including water waste heat recovery system, water cooling system, flue gas waste heat recovery system, power generation system, The water waste heat recovery system is connected in parallel with the water cooling system; The water waste heat recovery system is connected in series with the flue gas waste heat recovery system; The waste heat recovery system is connected to the power generation system.
2. The power generation system according to claim 1, characterized in that: The water waste heat recovery system comprises an internal combustion engine (1), a high-temperature cylinder jacket water pump (2), a first electric three-way valve (5), a second electric three-way valve (6), a high-temperature cylinder jacket water radiator (3) and a plate heat exchanger (4); The high-temperature cylinder jacket water pump (2) inputs the high-temperature cylinder jacket water in the internal combustion engine (1) into the first electric three-way valve (5), and the high-temperature cylinder jacket water flows back to the internal combustion engine (1) after passing through the first electric three-way valve (5), the second electric three-way valve (6) and the high-temperature cylinder jacket water radiator (3).
3. The power generation system according to claim 2, characterized in that: The heat release side of the plate heat exchanger (4) is connected in parallel between the first electric three-way valve (5) and the second electric three-way valve (6).
4. The power generation system according to claim 1, characterized in that: The flue gas waste heat recovery system comprises a denitration device (7), a waste heat boiler (9), a chimney (10), an oil pump (8) and an evaporator (11); The flue gas of the internal combustion engine (1) passes through a denitration device (7) and a waste heat boiler (9) and is discharged from a chimney (10).
5. The power generation system according to claim 4, characterized in that: After flowing out of the waste heat boiler (9), the heat transfer medium flows sequentially through the heat release side of the evaporator (11), the oil pump (8), the heat absorption side of the plate heat exchanger (4), and the heat absorption side of the waste heat boiler (9).
6. The power generation system according to claim 1, characterized in that: The power generation system comprises an evaporator (11), an expander (12), a generator (13), a condenser (14), a working fluid pump (15), a cooling water pump (16) and a cooling tower (17); The heat source flows into the inlet of the working fluid pump (15) through the heat absorption side of the evaporator (11), the inlet of the expander (12) and the heat release side of the condenser (14), and then flows back to the evaporator (11) through the working fluid pump (15), completing the organic Rankine cycle.
7. The power generation system according to claim 6, characterized in that: The driving shaft of the generator (13) is connected to the output shaft of the expander (12), and the output end of the generator (13) is connected to the power grid.
8. The power generation system according to claim 6, characterized in that: The cooling water pump (16) pumps cooling water out of the cooling tower (17), and the cooling water flows through the condenser (14) and then flows back to the cooling tower (17).
9. The power generation system according to claim 5, characterized in that: The heat transfer medium is hot water or heat transfer oil.
10. The power generation system according to claim 6, characterized in that: The heat transfer medium and working medium used in the organic Rankine cycle are organic working fluids.