Exhaust waste heat and water recovery system of gas internal combustion engine
By employing components such as denitrification devices, feedwater heat exchangers, and condenser heat exchangers in the exhaust waste heat and water recovery system of a gas-fired internal combustion engine, the problem of high-temperature exhaust and water vapor in natural gas internal combustion engines that are difficult to recover and utilize has been solved, achieving efficient waste heat and water resource recovery and improving the economic benefits of the power generation system.
Patent Information
- Application Number
- CN202422734644.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-11
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-11-11
AI Technical Summary
Existing natural gas internal combustion engines produce exhaust gases that are high in temperature and contain water vapor, making them difficult to effectively recover and utilize. Traditional waste heat recovery methods are inefficient and require high equipment investment, especially in arid and water-scarce regions where resource utilization efficiency is low.
Design a waste heat and water recovery system for exhaust gas from a gas-fired internal combustion engine, including a denitrification component, a feedwater heat exchanger, a condenser heat exchanger, and a chimney. The system recovers high-temperature waste heat and water vapor through denitrification, heat exchange, and condensation processes, and improves energy conversion efficiency by combining a steam turbine and a feedwater pump.
It achieves efficient recovery of high-temperature waste heat and water vapor from internal combustion engine exhaust, improves resource utilization efficiency, reduces equipment investment and water consumption, and enhances the overall economic benefits of the power generation system.
Smart Images
Figure CN223536426U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of gas internal combustion engine technology, and in particular to a gas internal combustion engine exhaust waste heat and water recovery system. Background Technology
[0002] Currently, advanced large-scale natural gas internal combustion engines can achieve a thermal efficiency of over 45%, but their exhaust temperature is still as high as 300-500℃, and it contains a high concentration of water vapor. If the high-temperature exhaust of natural gas internal combustion engines is not utilized, it will result in a huge waste of resources. The traditional method of waste heat recovery from internal combustion engine exhaust is to add a waste heat boiler to generate electricity using the generated steam. However, due to the low parameters of the generated steam, the power generation efficiency is very low. At the same time, the equipment investment for adding a waste heat boiler power generation system is very high, resulting in poor overall economic benefits. In addition, for arid and water-scarce areas, fully recovering water from exhaust is also of great significance for improving resource utilization efficiency. Utility Model Content
[0003] In view of the above-mentioned technical problems of the high temperature and water vapor in the exhaust of existing natural gas internal combustion engines, which are difficult to recover and utilize, this utility model is proposed.
[0004] The purpose of this invention is to provide a waste heat recovery and water recovery system for exhaust gas from a gas-fired internal combustion engine, which aims to simultaneously recover high-temperature waste heat and water vapor in the exhaust gas.
[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution: a waste heat recovery system for exhaust gas from a gas-fired internal combustion engine and water recovery system, which includes a heat recovery unit. The heat recovery unit includes an internal combustion engine, a denitrification component, a feedwater heat exchanger, a condensing heat exchanger, and a chimney. The denitrification component is located on one side of the internal combustion engine, the feedwater heat exchanger is located on one side of the denitrification component, the condensing heat exchanger is located on one side of the feedwater heat exchanger, and the chimney is located on one side of the condensing heat exchanger.
[0006] The water recovery unit includes a steam turbine, a feedwater pump, and a boiler. The steam turbine is located on one side of the condenser heat exchanger, the feedwater pump is located on the other side of the condenser heat exchanger, and the boiler is located on one side of the feedwater heat exchanger.
[0007] As a preferred embodiment of the exhaust waste heat and water recovery system of the gas-fired internal combustion engine of this utility model, the high-temperature flue gas of the internal combustion engine enters the feedwater heat exchanger after passing through the denitrification component.
[0008] As a preferred embodiment of the exhaust waste heat and water recovery system of the present invention, wherein: the denitrification component is injected with an ammonia solution and removed from the flue gas by a catalytic reduction reaction (SCR).
[0009] As a preferred embodiment of the exhaust waste heat and water recovery system of the gas internal combustion engine of this utility model, the flue gas enters the condenser heat exchanger after the boiler feedwater absorbs the temperature in the feedwater heat exchanger.
[0010] As a preferred embodiment of the exhaust waste heat and water recovery system of the gas internal combustion engine of this utility model, wherein: the condenser heat exchanger is used to discharge the flue gas through the chimney.
[0011] As a preferred embodiment of the exhaust waste heat and water recovery system of the gas internal combustion engine of this utility model, wherein: the turbine condensate flows into the condenser heat exchanger to cool the flue gas.
[0012] As a preferred embodiment of the exhaust waste heat and water recovery system of the gas internal combustion engine of this utility model, the temperature of the condenser heat exchanger is between 40 and 60°C.
[0013] As a preferred embodiment of the exhaust waste heat and water recovery system of the gas internal combustion engine of this utility model, the water pump sends condensate into the water heat exchanger to absorb the high-temperature exhaust waste heat of the internal combustion engine.
[0014] As a preferred embodiment of the exhaust waste heat and water recovery system of the gas internal combustion engine of this utility model, the temperature of the water supply heat exchanger is between 100 and 140°C.
[0015] As a preferred embodiment of the exhaust waste heat and water recovery system of the gas internal combustion engine of this utility model, wherein: the boiler feedwater in the feedwater heat exchanger is sent into the boiler.
[0016] The beneficial effects of the exhaust waste heat and water recovery system of this utility model are as follows: After the high-temperature flue gas from the internal combustion engine is discharged, nitrogen oxides in the exhaust gas are removed by the denitrification component. Then, the high-temperature flue gas enters the feedwater heat exchanger, where its temperature is absorbed by the boiler feedwater. After that, the exhaust gas enters the condensing heat exchanger to cool down before being discharged from the chimney. At the same time, the turbine condensate enters the condensing heat exchanger to cool the gas. The heated turbine condensate is pressurized by the feedwater pump and sent to the feedwater heat exchanger to further absorb the high-temperature exhaust waste heat from the internal combustion engine. Finally, the boiler feedwater flowing out of the feedwater heat exchanger is sent to the boiler. In this way, the high-temperature exhaust gas is utilized and the water vapor in the flue gas is reused. Attached Figure Description
[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Among them:
[0018] Figure 1This is a diagram illustrating the waste heat recovery system for exhaust gas from a gas-fired internal combustion engine and the water recovery system of this utility model. Detailed Implementation
[0019] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.
[0020] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.
[0021] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single embodiment or an embodiment selectively excluded from other embodiments.
[0022] Example 1
[0023] Reference Figure 1 This is the first embodiment of the present invention. This embodiment provides a waste heat recovery and water recovery system for exhaust gas of a gas internal combustion engine, including a heat recovery unit 100 and a water recovery unit 200.
[0024] Preferably, the heat recovery unit 100 includes an internal combustion engine 101, a denitrification component 102, a feedwater heat exchanger 103, a condensing heat exchanger 104, and a chimney 105. The denitrification component 102 is disposed on one side of the internal combustion engine 101 and is used to reduce and remove nitrogen oxides in the high-temperature flue gas of the internal combustion engine 101. The feedwater heat exchanger 103 is disposed on one side of the denitrification component 102, and the heat of the high-temperature flue gas is absorbed by the boiler feedwater in the feedwater heat exchanger 103. The condensing heat exchanger 104 is disposed on one side of the feedwater heat exchanger 103, and the temperature of the exhaust gas is further absorbed in the condensing heat exchanger 104. The water vapor in the exhaust gas is condensed and discharged from the bottom. The chimney 105 is disposed on one side of the condensing heat exchanger 104, and the high-temperature flue gas of the internal combustion engine 101 is finally discharged from the chimney 105.
[0025] Preferably, the water recovery unit 200 includes a steam turbine 201, a feedwater pump 202, and a boiler 203. The steam turbine 201 is located on one side of the condenser heat exchanger 104. The condensate from the steam turbine 201 first enters the condenser heat exchanger 104 to cool the exhaust gas of the internal combustion engine 101. The feedwater pump 202 is located on the other side of the condenser heat exchanger 104. The condensate from the steam turbine 201, which has been preheated, is pressurized by the feedwater pump 202 and then sent to the feedwater heat exchanger 103 to further absorb the waste heat of the high-temperature exhaust gas of the internal combustion engine 101. The boiler 203 is located on one side of the feedwater heat exchanger 103. The boiler feedwater flowing out of the feedwater heat exchanger 103 is sent into the boiler 203.
[0026] In operation, the exhaust waste heat and water recovery system consists of two units. In the heat recovery unit 100, before the high-temperature flue gas from the internal combustion engine 101 enters the feedwater heat exchanger 103, the denitrification component 102 reduces and removes nitrogen oxides from the high-temperature flue gas. After the high-temperature flue gas enters the feedwater heat exchanger 103, its heat is absorbed by the boiler feedwater in the feedwater heat exchanger 103. Then, the exhaust gas enters the condensing heat exchanger 104, where its temperature is further absorbed. The water vapor in the exhaust gas is condensed and discharged from the bottom. Finally, the high-temperature flue gas from the internal combustion engine 101 is discharged from the chimney 105. In the water recovery unit 200, the condensate from the turbine 201 first enters the condensing heat exchanger 104 to cool the exhaust gas from the internal combustion engine 101. The condensate from the turbine 201, which has been preheated, is pressurized by the feedwater pump 202 and sent to the feedwater heat exchanger 103 to further absorb the waste heat of the high-temperature exhaust gas from the internal combustion engine 101. The boiler feedwater flowing out of the feedwater heat exchanger 103 is sent into the boiler 203.
[0027] Example 2
[0028] Reference Figure 1 This is the second embodiment of the present invention. Unlike the previous embodiment, the high-temperature flue gas from the internal combustion engine 101 enters the feedwater heat exchanger 103 after passing through the denitrification component 102. This is to denitrify the high-temperature flue gas discharged from the internal combustion engine 101.
[0029] Furthermore, the denitrification component 102 is injected with an ammonia solution to remove nitrogen oxides from the flue gas via a selective catalytic reduction (SCR) reaction. In this embodiment, the nitrogen oxides in the flue gas are removed by injecting an ammonia solution into the high-temperature flue gas and performing a selective catalytic reduction (SCR) reaction under the action of a catalyst.
[0030] Preferably, after the boiler feedwater absorbs the heat in the feedwater heat exchanger 103, the flue gas enters the condenser heat exchanger 104, and the heat recovery unit 100 absorbs the heat from the flue gas discharged from the internal combustion engine 101.
[0031] Preferably, the flue gas flows through the condenser heat exchanger 104 and is discharged through the chimney 105. The condenser heat exchanger 104 allows the heat of the flue gas discharged from the internal combustion engine 101 to be absorbed again, and condenses the water vapor in the exhaust gas and discharges it from the bottom. The remaining flue gas is discharged from the chimney 105, which reduces nitrogen oxide pollution.
[0032] In use, the high-temperature flue gas from the internal combustion engine 101 enters the feedwater heat exchanger 103 after passing through the denitrification component 102. Ammonia solution is injected into the high-temperature flue gas, and selective catalytic reduction (SCR) occurs under the action of a catalyst to remove nitrogen oxides from the flue gas. The boiler feedwater in the feedwater heat exchanger 103 absorbs the temperature of the flue gas and then enters the condensing heat exchanger 104. The condensing heat exchanger 104 absorbs the heat of the flue gas discharged from the internal combustion engine 101 again and condenses the water vapor in the exhaust gas before it is discharged from the bottom. The remaining flue gas is discharged from the chimney 105, which reduces nitrogen oxide pollution.
[0033] Example 3
[0034] Reference Figure 1 This is the third embodiment of the present invention. Unlike the previous embodiment, the condensate from the steam turbine 201 flows into the condenser heat exchanger 104 to cool the flue gas. The exhaust waste heat and water recovery system of the gas internal combustion engine combines the natural gas internal combustion engine with the coal-fired boiler.
[0035] Furthermore, the temperature of the condenser heat exchanger 104 is between 40 and 60°C, and the most preferred temperature in this embodiment is 50°C.
[0036] Preferably, the water pump 202 sends condensate into the water heat exchanger 103 to absorb the waste heat from the high-temperature exhaust of the internal combustion engine 101.
[0037] Furthermore, the temperature of the water heat exchanger 103 is between 100 and 140°C, and the most preferred temperature in this embodiment is 120°C.
[0038] Preferably, boiler feedwater is fed into boiler 203 from feedwater heat exchanger 103.
[0039] In operation, condensate from the turbine 201 flows into the condenser heat exchanger 104 to cool the flue gas. The natural gas internal combustion engine exhaust waste heat and water recovery system combines a natural gas internal combustion engine with a coal-fired boiler. The temperature of the condenser heat exchanger 104 is between 40 and 60°C, with an optimal temperature of 50°C. The feedwater pump 202 sends the condensate into the feedwater heat exchanger 103 to absorb the high-temperature exhaust waste heat from the internal combustion engine 101. The temperature of the feedwater heat exchanger 103 is between 100 and 140°C, with an optimal temperature of 120°C in this embodiment. Finally, the boiler feedwater in the feedwater heat exchanger 103 is sent into the boiler 203 for recycling. This not only improves the energy conversion efficiency of the internal combustion engine power generation system but also reduces the water consumption of the entire power generation system, thereby improving resource utilization efficiency.
[0040] It is important to note that the constructions and arrangements of this application shown in several different exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, those who consult this disclosure will readily understand that many modifications are possible (e.g., changes in the size, dimensions, structure, shape and proportion of various elements, as well as parameter values (e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, orientation, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in this application). For example, an element shown as integrally formed may be composed of multiple parts or elements, the position of elements may be inverted or otherwise altered, and the nature or number or position of discrete elements may be changed or altered. Therefore, all such modifications are intended to be included within the scope of this utility model. The order or sequence of any process or method steps may be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and not only structural equivalents but also equivalent structures. Without departing from the scope of this invention, other substitutions, modifications, alterations, and omissions may be made in the design, operation, and arrangement of the exemplary embodiments. Therefore, this invention is not limited to the specific embodiments, but extends to various modifications that still fall within the scope of the appended claims.
[0041] Furthermore, in order to provide a concise description of exemplary embodiments, not all features of actual embodiments (i.e., those features that are not relevant to the best mode of carrying out the present invention as currently considered, or those features that are not relevant to implementing the present invention) may be omitted.
[0042] It should be understood that numerous specific implementation decisions can be made during the development of any practical implementation, such as in any engineering or design project. Such development efforts may be complex and time-consuming, but for those skilled in the art who benefit from this disclosure, the development effort will be a routine work of design, manufacturing, and production without requiring much experimentation.
[0043] It should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.
Claims
1. A waste heat recovery and water recovery system for exhaust gas from a gas-fired internal combustion engine, characterized in that: include, A heat recovery unit (100) includes an internal combustion engine (101), a denitrification assembly (102), a feedwater heat exchanger (103), a condensing heat exchanger (104), and a chimney (105). The denitrification assembly (102) is located on one side of the internal combustion engine (101), the feedwater heat exchanger (103) is located on one side of the denitrification assembly (102), the condensing heat exchanger (104) is located on one side of the feedwater heat exchanger (103), and the chimney (105) is located on one side of the condensing heat exchanger (104). A water recovery unit (200) is provided, comprising a steam turbine (201), a feedwater pump (202), and a boiler (203). The steam turbine (201) is located on one side of the condensing heat exchanger (104), the feedwater pump (202) is located on the other side of the condensing heat exchanger (104), and the boiler (203) is located on one side of the feedwater heat exchanger (103).
2. The exhaust waste heat and water recovery system for a gas-fired internal combustion engine as described in claim 1, characterized in that: The high-temperature flue gas from the internal combustion engine (101) enters the feedwater heat exchanger (103) after passing through the denitrification component (102).
3. The exhaust waste heat and water recovery system for a gas-fired internal combustion engine as described in claim 2, characterized in that: The denitrification component (102) is injected with an ammonia solution to remove nitrogen oxides from the flue gas via a catalytic reduction reaction (SCR).
4. The exhaust waste heat and water recovery system for a gas-fired internal combustion engine as described in claim 1 or 3, characterized in that: After the boiler feedwater absorbs the temperature in the feedwater heat exchanger (103), the flue gas enters the condenser heat exchanger (104).
5. The exhaust waste heat and water recovery system for a gas-fired internal combustion engine as described in claim 4, characterized in that: The condenser heat exchanger (104) is used to discharge flue gas through the chimney (105).
6. The exhaust waste heat and water recovery system for a gas-fired internal combustion engine as described in claim 1 or 5, characterized in that: The steam turbine (201) condensate flows into the condenser heat exchanger (104) to cool the flue gas.
7. The exhaust waste heat and water recovery system for a gas-fired internal combustion engine as described in claim 6, characterized in that: The temperature of the condenser heat exchanger (104) is between 40 and 60°C.
8. The exhaust waste heat and water recovery system for a gas-fired internal combustion engine as described in claim 7, characterized in that: The water pump (202) sends condensate into the water heat exchanger (103) to absorb the waste heat from the high-temperature exhaust of the internal combustion engine (101).
9. The exhaust waste heat and water recovery system for a gas-fired internal combustion engine as described in claim 8, characterized in that: The temperature of the water supply heat exchanger (103) is between 100 and 140°C.
10. The waste heat recovery system for gas-fired internal combustion engines and water recovery system as described in claim 9, characterized in that: The boiler feedwater in the feedwater heat exchanger (103) is fed into the boiler (203).