Cooling tower heat energy recycling system and method of carbon capture system

Abstract

According to the cooling tower heat energy recycling system and method of the carbon capture system, a coil pipe is additionally arranged above a cooling tower, waste gas heat is used for heating water in the coil pipe, then hot water in the coil pipe is conveyed into a hot water tank through a pipeline, and therefore energy consumption of the hot water tank is reduced, and energy consumption of the hot water tank is reduced. The heat energy of the waste gas of the main engine is utilized, the energy consumption of the hot water tank is reduced, and the method is energy-saving, economical and environment-friendly.

Description

Technical Field

[0001] This invention relates to the field of shipbuilding technology, and in particular to a cooling tower thermal energy reuse system and method for a carbon capture system. Background Technology

[0002] While dual-fuel main engines can reduce pollutant emissions when operating in gas combustion mode, they still produce a significant amount of carbon dioxide (CO2) after combustion. To reduce CO2 emissions, carbon capture systems are increasingly being implemented. These systems first clean the main engine exhaust gas at approximately 240°C and then reduce its temperature to around 45°C-60°C. During this process, a large amount of heat from the exhaust gas is wasted. Furthermore, hot water in the ship's superstructure is typically supplied by hot water tanks, which usually use electric or steam heating. Both methods consume shipboard energy. Therefore, how to utilize the heat from the exhaust gas in the cooling tower while simultaneously reducing the energy consumption of the hot water tanks has become a pressing issue. Summary of the Invention

[0003] In view of this, the present invention provides a cooling tower thermal energy reuse system and method for a carbon capture system to solve the problems existing in the background art.

[0004] A cooling tower thermal energy reuse system for a carbon capture system includes a cooling tower, a cooler, coils, a fresh water pressure tank, and a hot water tank. The exhaust gas outlet at the top of the cooling tower is connected to the carbon capture system. The exhaust gas inlet in the middle of the cooling tower is connected to the exhaust gas outlet of the ship's main engine through a pipeline. The liquid outlet at the bottom of the cooling tower is connected to the hot side inlet of the cooler through a first cleaning pipe. The hot side outlet of the cooler is connected to a second cleaning pipe, and the second cleaning pipe extends into the tower body of the cooling tower. The section of the second cleaning pipe that extends into the tower body is equipped with multiple spray heads located above the air inlet of the cooling tower to form an exhaust gas cooling and cleaning circulation pipeline. A first circulation pump is installed on the first cleaning pipe. The coil is installed inside the cooling tower and above the spray head. The inlet of the coil is connected to the outlet of the fresh water pressure tank through the first fresh water heating pipe, and the outlet of the coil is connected to the inlet of the hot water tank through the second fresh water heating pipe to form a fresh water heating pipeline. The hot water outlet of the hot water tank is connected to the hot water pipe inlet of the upper building through a first hot water delivery pipe, and the hot water pipe outlet of the upper building is connected to the hot water inlet of the hot water tank through a second hot water delivery pipe to form a hot water delivery circulation pipeline. A second circulation pump is installed on the second hot water delivery pipe.

[0005] The first freshwater heating pipe is equipped with a first shut-off check valve and a second shut-off check valve, and the second freshwater heating pipe is equipped with a third shut-off check valve and a fourth shut-off check valve. A freshwater filling pipe is also connected to the section of the first freshwater heating pipe located at the rear end of the second shut-off check valve. The end of the freshwater filling pipe extends into the interior of the cooling tower, and a first shut-off valve is installed on the freshwater filling pipe.

[0006] A spare connecting pipe is also connected between the first freshwater heating pipe and the second freshwater heating pipe. One end of the spare connecting pipe is connected to the pipe section of the first freshwater heating pipe located between the first shut-off check valve and the second shut-off check valve, and the other end is connected to the pipe section of the second freshwater heating pipe located between the third shut-off check valve and the fourth shut-off check valve. A second shut-off valve is installed on the spare connecting pipe.

[0007] The hot water outlet of the hot water tank is located at the upper part of its body, the hot water inlet is located at the lower part of its body, and the liquid inlet of the hot water tank is located between its hot water outlet and hot water inlet.

[0008] A method for reusing the thermal energy of a cooling tower using the aforementioned system specifically includes the following steps: Fresh water in the cooling tower enters the cooler through the first cleaning pipe and exchanges heat with seawater. The seawater cools the fresh water, and the resulting lower-temperature fresh water flows out through the spray head on the second cleaning pipe. It sprays the main exhaust gas entering the tower from the exhaust gas inlet in the middle of the cooling tower from top to bottom to cool and clean the main exhaust gas. Fresh water that absorbs some of the heat from the main unit's exhaust gas continues to flow from the bottom of the cooling tower into the first cleaning pipe, while the main unit's exhaust gas, after being cooled once, continues to flow upward. The ambient temperature fresh water in the fresh water pressure tank enters the coil through the first fresh water heating pipe and exchanges heat with the main unit exhaust gas that has been cooled once and flows outside the coil. The residual heat in the main unit exhaust gas is used to heat the fresh water in the coil to form hot water at 50-60°C. The 50-60°C hot water flows into the hot water tank through the second fresh water heating pipe. The main unit exhaust gas that has been cooled twice becomes 45-60°C exhaust gas. The 45-60°C exhaust gas flows into the carbon capture system from the top of the cooling tower. The hot water tank supplies 60°C hot water to the upper floors through the first hot water delivery pipe.

[0009] After hot water at 50-60℃ flows into the hot water tank through the second freshwater heating pipe, the sensor on the hot water tank will detect the temperature of the hot water inside. If the hot water temperature does not reach 60℃, it will be heated to 60℃ by steam heating or electric heating, and then supplied to the upper building through the first hot water delivery pipe.

[0010] Before using the cooling tower, the first freshwater heating pipe and the freshwater filling pipe must be opened, while the second freshwater heating pipe is kept closed. Use the first freshwater heating pipe and the freshwater filling pipe to fill the cooling tower with room temperature freshwater from the freshwater pressure tank.

[0011] If the coil malfunctions or breaks, the second shut-off check valve on the first freshwater heating pipe is closed, and the second shut-off valve on the backup connecting pipe is opened. The regular freshwater in the freshwater pressure tank is then transported to the hot water tank sequentially through the first freshwater heating pipe, the backup connecting pipe, and the second freshwater heating pipe to ensure the hot water supply to the upper floors.

[0012] The beneficial effects of this invention are: This invention adds a coil above the cooling tower, using the heat from the exhaust gas to heat the water inside the coil. The hot water in the coil is then transported to the hot water tank through pipelines, thereby reducing the energy consumption of the hot water tank. This method utilizes the heat energy of the exhaust gas from the main unit while reducing the energy consumption of the hot water tank, making it both energy-saving and environmentally friendly. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the cooling tower thermal energy reuse system of the present invention.

[0015] The meanings of the labels in the diagram are as follows: 1 is the cooling tower, 2 is the first circulating pump, 3 is the cooler, 4 is the spray head, 5 is the freshwater pressure tank, 6 is the hot water tank, 7 is the superstructure, 8 is the second circulating pump, 9 is the first shut-off check valve, 10 is the second shut-off check valve, 11 is the coil, 12 is the third shut-off check valve, 13 is the fourth shut-off check valve, 14 is the first shut-off valve, 15 is the second shut-off valve, 16 is the first cleaning pipe, 17 is the second cleaning pipe, 18 is the first freshwater heating pipe, 19 is the second freshwater heating pipe, 20 is the first hot water delivery pipe, 21 is the second hot water delivery pipe, 22 is the freshwater injection pipe, 23 is the spare connecting pipe, and 24 is the carbon capture system. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0017] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The singular forms “a,” “the,” and “the” as used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0018] It should be understood that although the terms first, second, third, etc., may be used in this disclosure to describe various information, such information should not be limited to these terms and should not be construed as indicating or implying relative importance. These terms are used only to distinguish information of the same type from one another. For example, without departing from the scope of this disclosure, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0019] In the description of this invention, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two components. They can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0020] To better understand the technical solution of the present invention, the present invention will be described in detail below with reference to the accompanying drawings.

[0021] The present invention provides a cooling tower thermal energy reuse system for a carbon capture system, comprising a cooling tower 1, a cooler 3, a coil 11, a fresh water pressure tank 5, and a hot water tank 6.

[0022] The exhaust gas outlet at the top of the cooling tower 1 is connected to the carbon capture system. The exhaust gas inlet in the middle of the cooling tower 1 is connected to the exhaust gas outlet of the ship's main engine through a pipeline. The liquid outlet at the bottom of the cooling tower 1 is connected to the hot side inlet of the cooler 3 through the first cleaning pipe 16. The first circulating pump 2 is installed on the first cleaning pipe 16. The hot side outlet of the cooler 3 is connected to the second cleaning pipe 17 and the second cleaning pipe 17 extends into the tower body of the cooling tower 1. The section of the second cleaning pipe 17 that extends into the tower body is equipped with multiple spray heads 4 located above the air inlet of the cooling tower 1 to form an exhaust gas cooling and cleaning circulation pipeline.

[0023] The first circulating pump 2 pumps fresh water from the cooling tower 1 into the cooler 3 through the first cleaning pipe 16. The fresh water entering the cooler 3 exchanges heat with the low-temperature seawater, using the seawater to cool the fresh water. The resulting lower-temperature fresh water flows along the second cleaning pipe 17 and is sprayed from top to bottom through the spray nozzles 4 on the second cleaning pipe 17. This sprays the main unit exhaust gas entering the tower from the exhaust gas inlet in the middle of the cooling tower 1 from top to bottom. During this process, the lower-temperature fresh water is sprayed from top to bottom, while the 240°C main unit exhaust gas flows from bottom to top. The main unit exhaust gas exchanges heat with the lower-temperature fresh water, thereby cooling and cleaning the main unit exhaust gas. The fresh water that has absorbed some of the heat from the main unit exhaust gas continues to flow from the bottom of the cooling tower 1 into the first cleaning pipe 16, while the main unit exhaust gas, after being cooled once, continues to flow upward.

[0024] The coil 11 is installed inside the cooling tower 1 and above the spray head 4. The inlet of the coil 11 is connected to the outlet of the freshwater pressure tank 5 through the first freshwater heating pipe 18, and the outlet of the coil 11 is connected to the inlet of the hot water tank 6 through the second freshwater heating pipe 19, thus forming a freshwater heating pipeline. The internal pressure of the freshwater pressure tank 5 is approximately 0.7 MPa.

[0025] A first shut-off check valve 9 and a second shut-off check valve 10 are installed on the first freshwater heating pipe 18, and a third shut-off check valve 12 and a fourth shut-off check valve 13 are installed on the second freshwater heating pipe 19. The ambient temperature freshwater in the freshwater pressure tank 5 enters the coil 11 through the first freshwater heating pipe 18, where it exchanges heat with the exhaust gas from the main unit that has undergone primary cooling flowing outside the coil 11. The residual heat in the exhaust gas is used to heat the freshwater in the coil 11 to form hot water at 50-60°C. The resulting hot water flows into the hot water tank 6 through the second freshwater heating pipe 19, while the exhaust gas from the main unit, after secondary cooling, becomes exhaust gas at 45-60°C. This 45-60°C exhaust gas flows from the top of the cooling tower 1 into the carbon capture system 24.

[0026] The hot water outlet of the hot water tank 6 is connected to the hot water inlet of the upper building 7 via a first hot water delivery pipe 20. The hot water outlet of the upper building 2 is connected to the hot water inlet of the hot water tank 6 via a second hot water delivery pipe 21, forming a hot water delivery circulation pipeline. A second circulation pump 8 is installed on the second hot water delivery pipe 21. The hot water outlet of the hot water tank 6 is located at the upper part of its body, the hot water inlet is located at the lower part of its body, and the liquid inlet of the hot water tank 6 is located between its hot water outlet and hot water inlet.

[0027] After the second freshwater heating pipe 19 delivers hot water at 50-60℃ to the hot water tank 6, the sensor on the hot water tank 6 will detect the temperature of the hot water inside. If the hot water temperature does not reach 60℃, the hot water will be heated to 60℃ by steam heating or electric heating, and then supplied to the upper building 7 through the first hot water delivery pipe 20.

[0028] Preferably, a freshwater filling pipe 22 is connected to the section of the first freshwater heating pipe 18 located at the rear end of the second shut-off check valve 10. The end of the freshwater filling pipe 22 extends into the interior of the cooling tower 1, and a first shut-off valve 14 is installed on the freshwater filling pipe 22. Before the system is put into use, the first shut-off check valve 9, the second shut-off check valve 10, and the first shut-off valve 14 are opened, and room-temperature freshwater in the freshwater pressure tank 5 can be added to the cooling tower 1 through the first freshwater heating pipe 18 and the freshwater filling pipe 22.

[0029] Preferably, a spare connecting pipe 23 is also connected between the first freshwater heating pipe 22 and the second freshwater heating pipe 19. One end of the spare connecting pipe 23 is connected to the pipe section of the first freshwater heating pipe 18 located between the first shut-off check valve 9 and the second shut-off check valve 10, and the other end is connected to the pipe section of the second freshwater heating pipe 19 located between the third shut-off check valve 12 and the fourth shut-off check valve 13. A second shut-off valve 15 is installed on the spare connecting pipe 23. When the coil 11 ruptures or other problems occur, the second shut-off check valve 10 on the first freshwater heating pipe 18 is closed, the second shut-off valve 15 on the spare connecting pipe 23 is opened, and the fourth shut-off check valve 13 remains open. The regular freshwater in the freshwater pressure tank 5 can be sequentially transported to the hot water tank 6 through the first freshwater heating pipe 18, the spare connecting pipe 23, and the second freshwater heating pipe 19 to ensure the normal supply of hot water to the upper floors.

[0030] When arranging cooling tower 1, cooler 3, fresh water pressure tank 5 and hot water tank 6, in order to ensure the normal operation of the entire system, cooling tower 1 should be about 25m higher than fresh water pressure tank 5, cooler 3 should be about 14m higher than fresh water pressure tank 5, and hot water tank 6 should be about 10m higher than fresh water pressure tank 5.

[0031] The present invention also provides a method for reusing the thermal energy of a cooling tower using the system described above, specifically including the following steps: Fresh water in cooling tower 1 enters cooler 3 through first cleaning pipe 16 to exchange heat with seawater. The seawater cools the fresh water, and the resulting lower-temperature fresh water flows out through spray head 4 on second cleaning pipe 17 to spray the main exhaust gas entering the tower from the exhaust gas inlet in the middle of cooling tower 1 from top to bottom, so as to cool and clean the main exhaust gas. Fresh water that absorbs some of the heat from the exhaust gas continues to flow from the bottom of the cooling tower 1 into the first cleaning pipe 16, while the exhaust gas from the main unit, after being cooled once, continues to flow upward. The ambient temperature fresh water in the fresh water pressure tank 5 enters the coil 11 through the first fresh water heating pipe 18 and exchanges heat with the main unit exhaust gas that has been cooled once and flows outside the coil 11. The residual heat in the main unit exhaust gas is used to heat the fresh water in the coil 11 to form hot water at 50-60°C. The 50-60°C hot water flows into the hot water tank 6 through the second fresh water heating pipe 19. The main unit exhaust gas that has been cooled twice becomes 45-60°C exhaust gas. The 45-60°C exhaust gas flows into the carbon capture system from the top of the cooling tower 1. The hot water tank 6 supplies 60°C hot water to the upper building 7 through the first hot water delivery pipe 20.

[0032] Preferably, after hot water at 50-60℃ flows into the hot water tank 6 through the second fresh water heating pipe 19, the sensor on the hot water tank 6 will detect the temperature of the hot water inside. If the hot water temperature does not reach 60℃, the hot water will be heated to 60℃ by steam heating or electric heating, and then supplied to the upper building 7 through the first hot water delivery pipe 20.

[0033] Preferably, before using the cooling tower 1, the first freshwater heating pipe 18 and the freshwater filling pipe 22 need to be opened, while the second freshwater heating pipe 19 is kept closed. The room temperature freshwater in the freshwater pressure tank 5 is then added to the cooling tower 1 using the first freshwater heating pipe 18 and the freshwater filling pipe 22.

[0034] Preferably, if the coil 11 malfunctions or breaks, the second shut-off check valve 10 on the first freshwater heating pipe 18 is closed, and the second shut-off valve 15 on the backup connecting pipe 23 is opened. The regular freshwater in the freshwater pressure tank 5 is then transported to the hot water tank 6 through the first freshwater heating pipe 18, the backup connecting pipe 23, and the second freshwater heating pipe 19 to ensure the hot water supply to the upper floors.

[0035] It should be understood that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A cooling tower thermal energy recovery system for a carbon capture system, characterized in that, It includes a cooling tower (1), a cooler (3), a coil (11), a fresh water pressure tank (5), and a hot water tank (6); The exhaust gas outlet at the top of the cooling tower (1) is connected to the carbon capture system. The exhaust gas inlet in the middle of the cooling tower (1) is connected to the exhaust gas outlet of the ship's main engine through a pipeline. The liquid outlet at the bottom of the cooling tower (1) is connected to the hot side inlet of the cooler (3) through the first cleaning pipe (16). The hot side outlet of the cooler (3) is connected to the second cleaning pipe (17), and the second cleaning pipe (17) extends into the tower body of the cooling tower (1). The section of the second cleaning pipe (17) extending into the tower body is equipped with multiple spray heads (4) located above the air inlet of the cooling tower (1) to form an exhaust gas cooling and cleaning circulation pipeline. A first circulation pump (2) is installed on the first cleaning pipe (16). The coil (11) is installed inside the cooling tower (1) and above the spray head (4). The inlet of the coil (11) is connected to the outlet of the fresh water pressure tank (5) through the first fresh water heating pipe (18), and the outlet of the coil (11) is connected to the inlet of the hot water tank (6) through the second fresh water heating pipe (19) to form a fresh water heating pipeline. The hot water outlet of the hot water tank (6) is connected to the hot water pipe inlet of the superstructure (7) through the first hot water delivery pipe (20), and the hot water pipe outlet of the superstructure (2) is connected to the hot water inlet of the hot water tank (6) through the second hot water delivery pipe (21) to form a hot water delivery circulation pipeline. A second circulation pump (8) is installed on the second hot water delivery pipe (21).

2. The cooling tower thermal energy recovery system of the carbon capture system according to claim 1, characterized in that, The first freshwater heating pipe (18) is equipped with a first shut-off check valve (9) and a second shut-off check valve (10), and the second freshwater heating pipe (19) is equipped with a third shut-off check valve (12) and a fourth shut-off check valve (13). A fresh water filling pipe (22) is connected to the section of the first fresh water heating pipe (18) located at the rear end of the second shut-off check valve (10). The end of the fresh water filling pipe (22) extends into the interior of the cooling tower (1). A first shut-off valve (14) is installed on the fresh water filling pipe (22).

3. The cooling tower thermal energy recovery system of the carbon capture system according to claim 1, characterized in that, A spare connecting pipe (23) is also connected between the first freshwater heating pipe (22) and the second freshwater heating pipe (19). One end of the spare connecting pipe (23) is connected to the pipe section of the first freshwater heating pipe (18) located between the first shut-off check valve (9) and the second shut-off check valve (10), and the other end is connected to the pipe section of the second freshwater heating pipe (19) located between the third shut-off check valve (12) and the fourth shut-off check valve (13). A second shut-off valve (15) is installed on the spare connecting pipe (23).

4. The cooling tower thermal energy recovery system of the carbon capture system according to claim 1, characterized in that, The cooling tower (1), cooler (3) and hot water tank (6) are all installed at a higher height than the fresh water pressure tank (5).

5. The cooling tower thermal energy recovery system of the carbon capture system according to claim 1, characterized in that, The hot water outlet of the hot water tank (6) is located at the upper part of its body, the hot water inlet is located at the lower part of its body, and the liquid inlet of the hot water tank (6) is located between its hot water outlet and hot water inlet.

6. A method for reusing the thermal energy of a cooling tower using the system described in any one of claims 1-5, characterized in that, Specifically, the following steps are included: Fresh water in the cooling tower (1) enters the cooler (3) through the first cleaning pipe (16) to exchange heat with seawater. The seawater is used to cool the fresh water, and the resulting lower-temperature fresh water flows out through the spray head (4) on the second cleaning pipe (17) to spray the main exhaust gas entering the tower from the exhaust gas inlet in the middle of the cooling tower (1) from top to bottom, so as to cool and clean the main exhaust gas. Fresh water that absorbs some of the heat from the exhaust gas continues to flow from the bottom of the cooling tower (1) into the first cleaning pipe (16), while the exhaust gas from the main unit, after being cooled once, continues to flow upward. The ambient temperature fresh water in the fresh water pressure tank (5) enters the coil (11) through the first fresh water heating pipe (18) and exchanges heat with the main engine exhaust gas that has been cooled once and flows outside the coil (11). The residual heat in the main engine exhaust gas is used to heat the fresh water in the coil (11) to form hot water at 50-60°C. The 50-60°C hot water flows into the hot water tank (6) through the second fresh water heating pipe (19). The main engine exhaust gas that has been cooled twice becomes 45-60°C exhaust gas. The 45-60°C exhaust gas flows into the carbon capture system from the top of the cooling tower (1). The hot water tank (6) supplies 60°C hot water to the upper building (7) through the first hot water delivery pipe (20).

7. The method for reusing the thermal energy of a cooling tower in a carbon capture system according to claim 6, characterized in that, After the 50-60℃ hot water flows into the hot water tank (6) through the second fresh water heating pipe (19), the sensor on the hot water tank (6) will detect the temperature of the hot water inside. If the hot water temperature does not reach 60℃, the hot water will be heated to 60℃ by steam heating or electric heating, and then supplied to the upper building (7) through the first hot water delivery pipe (20).

8. The method for reusing the thermal energy of a cooling tower in a carbon capture system according to claim 6, characterized in that, Before using the cooling tower (1), the first fresh water heating pipe (18) and the fresh water filling pipe (22) need to be opened, while the second fresh water heating pipe (19) is kept closed. The room temperature fresh water in the fresh water pressure tank (5) is added to the cooling tower (1) using the first fresh water heating pipe (18) and the fresh water filling pipe (22).

9. The method for reusing the thermal energy of a cooling tower in a carbon capture system according to claim 6, characterized in that, If the coil (11) malfunctions or breaks, the second shut-off check valve (10) on the first freshwater heating pipe (18) is closed, and the second shut-off valve (15) on the spare connecting pipe (23) is opened. The regular freshwater in the freshwater pressure tank (5) is then transported to the hot water tank (6) through the first freshwater heating pipe (18), the spare connecting pipe (23), and the second freshwater heating pipe (19) to ensure the hot water supply to the upper building.

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