Heat energy utilization system, using method and ship

Abstract

The invention discloses a heat energy utilization system, a using method and a ship. The heat energy utilization system comprises an equipment cooling circulation pipeline and a hot cooling medium output. Cold seawater flows in the seawater pipeline; the temperature difference energy power generation module comprises a first heat exchange area, a second heat exchange area and a working medium circulation loop, the equipment cooling circulation pipeline correspondingly exchanges heat with the first heat exchange area, the seawater pipeline correspondingly exchanges heat with the second heat exchange area, and the first heat exchange area and the second heat exchange area are arranged in the working medium circulation loop in series. The liquid working medium absorbs heat, the gaseous working medium releases heat, and the liquid working medium and the gaseous working medium convert forms in the working medium circulation loop and convert energy into electric energy. The use method comprises a cooling mode, a maximum power generation mode, a frequency modulation mode and an emergency mode, and the ship applicable heat energy utilization system and the use method thereof can be a deepwater drilling ship.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ship cold energy utilization and thermal management, in particular to a thermal energy utilization system, a use method and a ship. BACKGROUND

[0002] The traditional deepwater drilling ship consumes a huge amount of energy and produces a large amount of waste heat during deepwater drilling operation. In the traditional technology, the ocean temperature difference energy power generation system and the conventional ship central cooling system are simply superimposed to realize the cooling and recovery of waste heat of the ship.

[0003] The traditional technology has certain shortcomings, such as 1) the ocean temperature difference energy power generation project needs to independently lay and maintain a special cold water pipe of hundreds to thousands of kilometers to obtain a low-temperature cold source, which is a huge project, has a high initial investment and operation and maintenance cost, and has poor economic efficiency; 2) the deepwater drilling device energy recovery method cannot effectively recover a large amount of medium and low temperature waste heat generated during equipment operation, and the heat is directly discharged into the environment through the cooling system, which is a huge energy loss; 3) the ship cooling system uses the surface seawater with a higher temperature as the final cold source, and the heat exchange temperature difference between the low-temperature fresh water is small, and the cooling efficiency is low. In order to meet the cooling requirements, a larger heat exchange area or a higher seawater flow is needed, which increases the system volume and pumping energy consumption; 4) the operation strategy of the temperature difference energy and energy recovery system is rigid, and cannot be dynamically adjusted according to the variable operation conditions (such as drilling, displacement, and parking) of the ship and the power grid load, which leads to low energy efficiency in some conditions, and even may affect the stability of the main operation system. SUMMARY

[0004] To solve at least one of the above technical problems, the present application provides a thermal energy utilization system, a use method and a ship, and the technical solutions adopted are as follows.

[0005] The thermal energy utilization system provided by the present application comprises: A device cooling circulation pipeline, the device cooling circulation pipeline comprises an input end and an output end, the input end is used for inputting a cooling medium, and the output end is used for outputting the cooling medium; A seawater pipeline, used for inputting and outputting cold seawater; A temperature difference energy power generation module, comprising a first heat exchange zone, a second heat exchange zone and a working medium circulation loop; wherein, The first heat exchange zone and the second heat exchange zone are arranged in series in the working medium circulation loop, the first heat exchange zone corresponds to heat exchange with the device cooling circulation pipeline, and the second heat exchange zone corresponds to heat exchange with the seawater pipeline; the first heat exchange zone is used for absorbing the heat energy of the device cooling circulation pipeline, the second heat exchange zone is used for releasing heat energy to the cold seawater, and the working medium circulation loop is used for circulation of the working medium. The working medium converts energy into electric energy through form conversion in the working medium circulation loop.

[0006] In some embodiments of the present application, the thermal energy utilization system further comprises a third heat exchange zone, and the equipment cooling circulation pipeline is further capable of exchanging heat with the seawater pipeline at the third heat exchange zone; the first heat exchange zone and the third heat exchange zone are used for sequentially exchanging heat with the cooling medium of the equipment cooling circulation pipeline.

[0007] In some embodiments of the present application, the seawater pipeline comprises a first pipe section and a second pipe section; the first pipe section is used for absorbing heat at the second heat exchange zone, and the second pipe section is used for absorbing heat at the third heat exchange zone; the first pipe section and the second pipe section are both provided with a flow control valve and a temperature sensor.

[0008] In some embodiments of the present application, the equipment cooling circulation pipeline is provided with a bypass pipe, one end of the bypass pipe is connected to the output end of the equipment cooling circulation pipeline, and the other end of the bypass pipe is connected to a pipe section of the equipment cooling circulation pipeline before the equipment cooling circulation pipeline enters the third heat exchange zone.

[0009] In some embodiments of the present application, a first valve is arranged between an interface of the equipment cooling circulation pipeline and a pipe section of the equipment cooling circulation pipeline before the first heat exchange zone, and / or a second valve is arranged on the bypass pipe.

[0010] In some embodiments of the present application, the first heat exchange zone comprises an evaporator, and the second heat exchange zone comprises a condenser; the working medium circulation loop comprises a working medium pump and a mechanical work mechanism, and the working medium sequentially circulates in the evaporator, the mechanical work mechanism, the condenser and the working medium pump; the evaporator is used for absorbing heat of the equipment cooling circulation pipeline to vaporize the liquid working medium, the condenser is used for liquefying the gaseous working medium by using the cold seawater, and the mechanical work mechanism is used for converting mechanical energy generated by work of the gaseous working medium into electrical energy.

[0011] In some embodiments of the present application, the thermal energy utilization system comprises a control structure, and the evaporator and the condenser are both provided with the pressure sensor and the temperature sensor; the control structure is electrically connected with the pressure sensor, the temperature sensor and the working medium pump, and the control structure is used for controlling the rotating speed of the working medium pump according to monitoring data.

[0012] In some embodiments of the present application, a flow control valve is arranged between the output end of the equipment cooling circulation pipeline and the first heat exchange zone, and the flow control valve is used for controlling the flow of the cooling medium.

[0013] The present application further provides a use method of the thermal energy utilization system as described above, comprising: The device cooling circulation pipeline and the seawater pipeline are each provided with a temperature sensor; the cooling medium temperature output by the device cooling circulation pipeline is a first preset temperature and is provided with a preset alarm temperature, and the following modes are included: A cooling mode: when the device is started or the device cooling circulation pipeline reaches the preset alarm temperature, the circulation efficiency of the working medium circulation loop is reduced and the heat exchange efficiency of the third heat exchange zone is increased. A maximum power generation mode: when the temperature of the device cooling circulation pipeline is higher than the first preset temperature and lower than the preset alarm temperature, the target temperature difference between the cold seawater and the cooling medium is controlled to be a first target temperature difference, and the circulation efficiency of the working medium circulation loop is increased. A frequency modulation mode: when the ship load power suddenly increases, the target temperature difference between the cold seawater and the cooling medium is controlled to be a first target temperature difference, and the circulation efficiency of the working medium circulation loop is increased; when the ship load power suddenly decreases, the target temperature difference between the cold seawater and the cooling medium is controlled to be a second target temperature difference, and the circulation efficiency of the working medium circulation loop is reduced. An emergency mode: when the device cooling circulation pipeline exceeds the preset alarm temperature and is greater than a preset temperature, the device is stopped, the first valve is closed, the second valve is opened, and the heat exchange efficiency of the third heat exchange zone is increased.

[0014] The application also provides a ship comprising the thermal energy utilization system as described above.

[0015] The application has at least the following beneficial effects: the application realizes the integration of device cooling and temperature difference power generation, the device cooling circulation pipeline and the first heat exchange zone exchange heat, the liquid working medium absorbs heat, the seawater pipeline and the second heat exchange zone exchange heat, the gaseous working medium releases heat, the liquid working medium and the gaseous working medium circulate to change the form, and an energy transmission path of device waste heat-working medium-cold seawater is constructed, which converts the originally discarded device waste heat into electric energy and improves the energy comprehensive utilization efficiency. The first and second heat exchange zones are arranged in series in the working medium circulation loop, so that the working medium completes the form conversion of heat absorption and vaporization and heat release and liquefaction in the circulation, converts into electric energy in the form conversion process, ensures the continuity of energy transmission and stable power generation, and adapts to the needs of long-term operation of the ship.

[0016] Additional aspects and advantages of the application will be in part apparent and in part pointed out hereinafter in the description. BRIEF DESCRIPTION OF DRAWINGS

[0017] The application will be further illustrated below in combination with the drawings and examples. It should be noted that the examples embodied in the following drawings are exemplary and are used to explain the application, and cannot be understood as a limitation on the application.

[0018] Figure 1 This is a schematic diagram of a thermal energy utilization system in one embodiment of this application.

[0019] Reference numerals: Equipment cooling circulation pipeline 100; main pipe section 110; first valve 111; short pipe 120; second valve 121; Seawater pipeline 200; electric submersible pump 210; seawater inlet 211; circulation pump 220; first pipe section 230; first outlet 231; third valve 232; second pipe section 240; second outlet 241; fourth valve 242; cryogenic seawater tank 250; third heat exchange zone 260; Thermoelectric power generation module 300; first heat exchange zone 310; second heat exchange zone 320; working fluid pump 330; mechanical working mechanism 340; Equipment 400; Drilling equipment 410; Marine power equipment 420; Living system equipment 430. Detailed Implementation

[0020] The following is combined Figure 1 The embodiments of this application are described in detail below, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0021] In the description of this application, it should be understood that the terms "center", "middle", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0022] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0023] In the description of the application, unless otherwise explicitly specified and limited, the terms "arrangement", "installation", "connected", "connected" should be understood broadly, for example: it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0024] In the description of the application, if the description of the terms "one embodiment", "some embodiments", "one example", "some examples", "some embodiments", "illustrative embodiments", "example", "specific example", "some examples" and the like 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 application. In the description, the illustrative description 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.

[0025] In conjunction with Figure 1 As shown, the application provides a thermal energy utilization system, comprising: A device cooling circulation pipeline 100, the device cooling circulation pipeline 100 comprises an input end and an output end, the input end is used for inputting a cooling medium, and the output end is used for outputting a hot cooling medium; A seawater pipeline 200, used for inputting and outputting cold seawater; A temperature difference power generation module 300, comprising a first heat exchange zone 310, a second heat exchange zone 320 and a working medium circulation loop; The first heat exchange zone 310 and the second heat exchange zone 320 are arranged in series in the working medium circulation loop, the first heat exchange zone 310 exchanges heat with the device cooling circulation pipeline 100, the second heat exchange zone 320 exchanges heat with the seawater pipeline, the first heat exchange zone 310 is used for absorbing the thermal energy of the device cooling circulation pipeline 100, the second heat exchange zone 320 is used for releasing thermal energy to cold seawater, and the working medium circulation loop is used for circulation of working medium. The working medium converts the form in the working medium circulation loop and converts the energy into electric energy.

[0026] Specifically, the working medium is a liquid working medium and / or a gaseous working medium, the liquid working medium can absorb the thermal energy of the device cooling circulation pipeline 100 in the first heat exchange zone 310, and the gaseous working medium can release heat to cold seawater in the second heat exchange zone 320; the liquid working medium and the gaseous working medium convert the form in the working medium circulation loop and convert the energy into electric energy.

[0027] The thermal energy utilization system of the application can be applied to a ship, i.e. a ship thermal energy utilization system.

[0028] The cooling medium flowing in the equipment cooling circulation pipeline 100 is fresh water. During the start-up and operation of the equipment 400, heat is generated. The cooling medium absorbs the heat of the equipment 400 and cools the equipment 400, forming a hot cooling medium. The hot cooling medium is output and concentrated from each of the equipment 400 into a single pipe section, and then transported from the main pipe section 110 to the first heat exchange zone 310.

[0029] The seawater pipeline 200 includes a seawater inlet 211 and a seawater outlet. Cold seawater is drawn in from the seawater inlet 211 and then discharged from the seawater outlet. The seawater pipeline 200 is an open-loop system, and an electric submersible pump 210 is installed on the seawater pipeline 200. When the electric submersible pump 210 is inserted into the seawater, cold seawater is continuously input from the seawater inlet 211 and discharged from the seawater outlet, which can achieve continuous flow of cold seawater within the seawater pipeline 200 and prevent sudden temperature changes in the cold seawater within the seawater pipeline 200 due to local temperature variations.

[0030] Thermoelectric power generation module 300 includes a shipborne closed-loop Rankine cycle power generation system; the working medium is an organic working fluid. The organic working fluid includes two forms: liquid and gaseous, and the liquid and gaseous working fluids can change forms in the working fluid circulation loop. The first heat exchange zone 310 is the area where the equipment cooling circulation pipe 100 exchanges heat with the liquid working fluid, and the second heat exchange zone 320 is the area where the gaseous working fluid exchanges heat with cold seawater. The first heat exchange zone 310 and the second heat exchange zone 320 are connected in series in the working fluid circulation loop. The equipment cooling circulation pipe 100 exchanges heat with the first heat exchange zone 310. The main pipe section 110 extends into the first heat exchange zone 310. The low-temperature, high-pressure liquid working fluid flows through the first heat exchange zone 310. The main pipe section 110 releases heat in the first heat exchange zone 310, and the low-temperature, high-pressure liquid working fluid absorbs heat in the first heat exchange zone 310. After absorbing heat, the low-temperature, high-pressure liquid working fluid forms a high-temperature, high-pressure gaseous working fluid. During the process of forming a low-pressure gaseous working fluid, the high-pressure gaseous working fluid converts energy into electrical energy, which is collected or used directly. At least a portion of the seawater pipe 200 extends into the second heat exchange zone 320. The second heat exchange zone 320 releases heat to the cold seawater and transfers temperature to the gaseous working fluid, cooling it down. The gaseous working fluid releases heat in the second heat exchange zone 320 to form a liquid working fluid. The liquid working fluid is then transported to the first heat exchange zone 310 to form a gaseous working fluid, which then reverts to a liquid working fluid, thus completing the working fluid cycle. The working fluid in the working fluid cycle loop can be ammonia.

[0031] This application integrates equipment cooling and thermoelectric power generation. Heat exchange occurs between the equipment cooling circulation pipe 100 and the first heat exchange zone 310, where the liquid working fluid absorbs heat. Simultaneously, heat exchange occurs between the seawater pipe 200 and the second heat exchange zone 320, where the gaseous working fluid releases heat. The liquid and gaseous working fluids circulate and undergo phase changes, converting previously unused equipment waste heat into electrical energy, thus improving overall energy utilization efficiency. The first and second heat exchange zones are connected in series in the working fluid circulation loop, allowing the working fluid to undergo phase changes from heat absorption and vaporization to heat release and liquefaction during circulation. This phase change process converts the fluid into electrical energy, ensuring continuous energy transfer and stable power generation, meeting the long-term operation requirements of equipment 400.

[0032] It is understood that the thermal energy utilization system of this application can be applied to deep-water drilling vessel systems. When a deep-water drilling vessel system performs drilling operations, it must place equipment to the seabed via a drilling riser or dedicated pipeline. This application is applied to deep-water drilling vessel systems where, simultaneously with placing drilling equipment to the seabed via the drilling riser or dedicated pipeline, an electric submersible pump 210 for extracting cryogenic seawater is placed along with the equipment to a depth of approximately 150-250 meters. The depth range of 150-250 meters is based on typical data from the global ocean thermocline, where seawater temperatures are stable between 10°C and 20°C, making it an excellent cryogenic cold source. It is understood that this depth can be adjusted according to actual needs.

[0033] The thermal energy utilization system includes a cryogenic seawater tank 250, which is installed on a seawater pipeline 200. An electric submersible pump 210 draws cryogenic seawater from the seawater inlet 211 into the cryogenic seawater tank 250 on the ship via the seawater pipeline 200. A circulation pump 220 delivers the cryogenic seawater to the thermal energy utilization system, providing it with a cryogenic cooling medium, i.e., cryogenic seawater.

[0034] Taking a deep-water drilling vessel system as an example, equipment 400 may include drilling equipment 410, ship propulsion equipment 420, and living system equipment 430, etc. The thermal energy utilization system of this application is applied to a deep-water drilling vessel system. Through integrated design, it solves the problem of separating power generation and cooling systems in existing technologies. While the drilling equipment is being placed on the seabed via the drilling riser or dedicated pipeline of the deep-water drilling vessel system, the electric submersible pump 210 for extracting cryogenic seawater is placed along with the equipment at a depth of approximately 150-250 meters. This eliminates the need for dedicated cold water pipelines, enabling thermoelectric power generation and reducing system deployment costs. The overall structure is compact, adaptable to the limited installation space of ships, and can meet the operational needs of special vessels such as deep-water drilling vessels.

[0035] Specifically, the first heat exchange zone 310 includes an evaporator, and the second heat exchange zone 320 includes a condenser; the working fluid circulation loop includes a working fluid pump 330 and a mechanical working mechanism 340, and the working fluid circulates sequentially through the evaporator, the mechanical working mechanism 340, the condenser, and the working fluid pump; the evaporator is used to absorb heat from the equipment cooling circulation pipe 100 to vaporize the liquid working fluid, the condenser is used to liquefy the gaseous working fluid using cold seawater, and the mechanical working mechanism 340 is used to convert the mechanical energy generated by the gaseous working fluid doing work into electrical energy.

[0036] The evaporator can be a shell-and-tube evaporator, with its inlet connected to the main pipe section 110. During operation, a low-temperature liquid working fluid, pressurized by the working fluid pump 330, enters the evaporator. The main pipe section 110 releases heat within the evaporator, while the liquid working fluid absorbs heat, transforming from a low-temperature, high-pressure liquid into a high-temperature, high-pressure gaseous working fluid. This high-temperature, high-pressure gaseous working fluid is input into a mechanical working mechanism 340, such as a turbine. The gaseous working fluid drives the turbine blades, generating mechanical energy. The turbine directly drives a generator to produce electricity. The gaseous working fluid discharged from the turbine enters the condenser. The condenser inlet is connected to a seawater pipe 200, where the gaseous working fluid releases heat to the cold seawater. The gaseous working fluid then forms a liquid working fluid within the condenser. The liquid working fluid is pressurized by the working fluid pump 330 and then transported back to the evaporator, completing the cycle.

[0037] In some embodiments, the thermal energy utilization system further includes a third heat exchange zone 260, in which the equipment cooling circulation pipeline 100 and the seawater pipeline 200 exchange heat; the cooling medium of the equipment cooling circulation pipeline 100 flows sequentially through the first heat exchange zone 310 and the third heat exchange zone 260. The third heat exchange zone 260 includes a plate cooler, through which the equipment cooling circulation pipeline 100 and the seawater pipeline 200 exchange heat. The main pipe section 110 of the equipment cooling circulation pipeline 100 inputs hot cooling medium to the first heat exchange zone 310, where the hot cooling medium undergoes exothermic cooling. The cooling medium in the equipment cooling circulation pipeline 100 flows sequentially to the first heat exchange zone 310 and the third heat exchange zone 260. One end of the equipment cooling circulation pipeline 100, exiting from the first heat exchange zone 310, is directed to the third heat exchange zone 260. The hot-side flow channel inlet of the plate cooler is connected to the equipment cooling circulation pipeline 100 via a pipeline. A section of the seawater pipeline 200 is connected to the cold-side flow channel inlet of the plate cooler. The equipment cooling circulation pipeline 100 and the seawater pipeline 200 exchange heat in the plate cooler, and the cooling medium in the equipment cooling circulation pipeline 100 releases heat again in the plate cooler. After heat exchange, the cooling medium in the equipment cooling circulation pipeline 100 is output from the plate cooler to absorb heat from the equipment 400. A section of the seawater pipeline 200 passes through the plate cooler and is transported into the sea from the seawater outlet, or passes through the plate cooler and connects to the inlet of the second heat exchange zone 320, passes through the second heat exchange zone 320, and is transported into the sea from the seawater outlet.

[0038] This embodiment achieves tiered cooling of the cooling medium by adding a third heat exchange zone 260. Heat is first recovered in the first heat exchange zone 310 for power generation, and then the third heat exchange zone 260 cools the cooling medium to the suitable temperature for the equipment 400. This ensures both power generation requirements and effective cooling of the equipment 400. Tiered cooling allows for the tiered recovery of waste heat, improving overall energy utilization, stabilizing the cooling medium temperature, and protecting ship equipment. Tiered cooling also makes the temperature gradient at each stage of heat exchange gentler, reducing thermal stress between the cooling medium and the heat exchange surface, and decreasing the rate of scale deposition. The use of a plate cooler makes the structure more compact and the heat exchange efficiency higher. Compared to traditional single cooling methods, the temperature drop of the cooling medium is more stable, avoiding equipment losses due to temperature fluctuations. Simultaneously, the third heat exchange zone 260 fully utilizes the cooling capacity of seawater, further improving overall energy utilization efficiency.

[0039] When applied to a deep-water drilling vessel system, the electric submersible pump 210 draws in low-temperature cold seawater through the seawater pipeline 200, and the circulating pump 220 pumps the low-temperature cold seawater to the second heat exchange zone 320 and the third heat exchange zone 260 of the thermoelectric power generation module 300, providing them with a low-temperature cooling medium, namely low-temperature cold seawater.

[0040] In some other embodiments, the first heat exchange zone 310, the second heat exchange zone 320, or the third heat exchange zone 260 may contain two pipes that are close to or attached to each other to achieve direct heat exchange between the contents of the pipes.

[0041] Specifically, after drawing cold seawater from the ESP 210 via the seawater pipeline 200, the cold seawater is first transported to the cryogenic seawater tank 250, and then discharged from the cryogenic seawater tank 250 to the heat exchange area. The cryogenic seawater tank 250 can store a certain amount of cold seawater, ensuring a stable supply. In actual operation, due to the variable operating conditions of ships, such as a surge in cooling demand due to drilling pump startup or changes in power generation demand due to grid fluctuations, the supply of cold seawater may also change at any time. This application incorporates the cryogenic seawater tank 250, which stores low-temperature cold seawater, ensuring a stable supply and rapid response to load changes without waiting for the ESP 210 to adjust its speed or experience startup delays. It also avoids complete system shutdown during maintenance, ensuring continuous cooling of critical ship equipment, reducing the risk of equipment overheating in emergency situations, and improving system reliability.

[0042] Specifically, the seawater pipeline 200 includes a first pipe section 230 and a second pipe section 240. The first pipe section 230 absorbs heat in the second heat exchange zone 320, and the second pipe section 240 absorbs heat from the equipment cooling circulation pipeline 100 in the third heat exchange zone 260. Both the first pipe section 230 and the second pipe section 240 are equipped with flow control valves and temperature sensors. The first pipe section 230 is equipped with a third valve 232, which is a flow control valve; the second pipe section 240 is equipped with a fourth valve 242, which is also a flow control valve. When cold seawater flows through the first pipe section 230, it flows to the second heat exchange zone 320, absorbs heat, and is discharged from the first output end 231. When cold seawater flows through the second pipe section 240, it flows to the third heat exchange zone 260, absorbs heat, and is discharged from the second output end 241. The seawater pipeline 200 is divided into two independent sections, the first section 230 and the second section 240, which supply cold seawater to the second heat exchange zone 320 and the third heat exchange zone 260, respectively. This achieves split control of the cold seawater flow. The flow control valve can be set to precisely adjust the flow rate of the cold seawater in the two sections according to different operating conditions, avoiding waste of cooling capacity. The temperature sensor can provide real-time feedback on the temperature of the cold seawater, providing data support for flow regulation and ensuring stable heat exchange effect. This design makes the distribution of cold seawater more flexible and can adapt to the dynamic changes in the ship's power generation and cooling needs, improving the system's adaptability.

[0043] In some embodiments, the equipment cooling circulation pipeline 100 is provided with a short connector 120. One end of the short connector 120 is connected to the output end of the equipment cooling circulation pipeline 100, and the other end of the short connector 120 is connected to the pipe section of the equipment cooling circulation pipeline 100 before entering the third heat exchange zone 260. By providing the short connector 120, a bypass channel for the equipment cooling circulation pipeline 100 is constructed. Using the short connector 120, all or part of the hot cooling medium of the equipment cooling circulation pipeline 100 can flow to the third heat exchange zone 260, increasing the cooling amount directly passing through the third heat exchange zone 260. It is understood that when the first heat exchange zone 310 malfunctions, requires maintenance, or is selectively not generating electricity and prioritizes direct cooling, the hot cooling medium can be transported to the third heat exchange zone 260 for cooling through the short connector 120.

[0044] Specifically, a first valve 111 is provided between the interface connecting the equipment cooling circulation pipeline 100 and the short pipe 120 and the section of the equipment cooling circulation pipeline 100 before the corresponding first heat exchange zone 310, and / or a second valve 121 is provided on the short pipe 120. With only the first valve 111 provided, when the first valve 111 is open, the equipment cooling circulation pipeline 100 can supply hot cooling medium to both the first heat exchange zone 310 and the third heat exchange zone 260, simultaneously generating electricity and providing cooling. When the first valve 111 is closed, a short circuit is achieved through the short pipe 120, and the hot cooling medium flows directly into the third heat exchange zone 260 for cooling. With only the second valve 121 provided, when the second valve 121 is open, the equipment cooling circulation pipeline 100 can supply hot cooling medium to both the first heat exchange zone 310 and the third heat exchange zone 260, simultaneously generating electricity and providing cooling. When the second valve 121 is closed, the medium first passes through the first heat exchange zone 310 and then through the third heat exchange zone 260, achieving cascade cooling. The first valve 111 and the second valve 121 can be set simultaneously. Depending on the ship's operating conditions, such as power generation priority, cooling priority, or grid frequency regulation, the heat distribution ratio of the two-stage heat exchange can be adjusted through the valves.

[0045] In some embodiments, the thermal energy utilization system includes a control structure (not shown in the figure). The evaporator is equipped with pressure and temperature sensors, and the condenser is also equipped with pressure and temperature sensors. The control structure is electrically connected to the pressure and temperature sensors of the evaporator and condenser, and to the working fluid pump 330, respectively. The control structure is used to control the rotational speed of the working fluid pump 330 based on monitoring data. The control structure employs a PLC controller. The signal output terminals of the pressure and temperature sensors are connected to the signal input terminals of the PLC controller via shielded cables. The signal output terminals of the PLC controller are connected to the frequency converter of the working fluid pump via cables. The PLC controller has a pre-stored database of thermodynamic parameters and control logic for the working fluid. It receives pressure and temperature signals from the evaporator and condenser in real time, calculates the superheat and subcooling of the working fluid, and then adjusts the rotational speed of the working fluid pump 330 via the frequency converter to ensure the working fluid circulation is in optimal condition.

[0046] For example, when the superheat of the working fluid in the evaporator is higher than a preset value, such as 5°C, the PLC controller controls the frequency converter to increase the speed of the working fluid pump 330, increasing the working fluid flow rate and reducing the superheat. When the subcooling of the working fluid in the condenser is lower than a preset value, such as 3°C, the PLC controller controls the frequency converter to decrease the speed of the working fluid pump 330, reducing the working fluid flow rate and increasing the subcooling. By setting up a PLC control structure, intelligent regulation of the working fluid circulation loop is achieved. The precise monitoring by pressure and temperature sensors provides reliable data support for the control logic. The PLC controller dynamically adjusts the speed of the working fluid pump 330 according to the thermodynamic parameters of the working fluid, ensuring that the working fluid always circulates under optimal conditions, thus improving power generation efficiency and system stability.

[0047] In some embodiments, a flow control valve is provided between the output end of the equipment cooling circulation pipeline 100 and the first heat exchange zone 310. The flow control valve is used to control the flow rate of the hot cooling medium. A first valve 111 is provided between the output end of the equipment cooling circulation pipeline 100 and the first heat exchange zone 310. The operator can set the valve opening according to the power generation requirements and equipment cooling status through the control system, thereby controlling the flow rate of the hot cooling medium flowing into the first heat exchange zone 310. Adjusting the flow rate according to the power generation requirements allows the heat exchange effect of the first heat exchange zone 310 to match the power generation requirements, avoiding energy waste due to excessive flow or insufficient power generation due to insufficient flow, thus adapting to different ship operating conditions.

[0048] Understandably, a flow control valve and temperature sensor can be installed on the pipe section at the seawater inlet 211. The valve opening can be automatically or manually adjusted to increase or decrease the cold seawater flow, ensuring the dynamic response quality and stability of the cooling system. This guarantees the safety of the main equipment while achieving optimal power generation efficiency under different operating conditions. It can also be coordinated with the electric submersible pump 210, circulation pump 220, third valve 232, and fourth valve 242 for adjustments, ensuring the dynamic response quality and stability of the cooling system and guaranteeing the safety of the main equipment while achieving optimal power generation efficiency under different operating conditions.

[0049] This application also provides a method for using the thermal energy utilization system as described above, including: Temperature sensors are installed in both the equipment cooling circulation pipe 100 and the seawater pipe 200; the temperature of the cooling medium output by the equipment cooling circulation pipe 100 is a first preset temperature and a preset alarm temperature is provided, including the following modes: Cooling mode: When the equipment 400 is started or the equipment cooling circulation pipeline 100 reaches the preset alarm temperature, the circulation efficiency of the working fluid circulation loop is reduced and the heat exchange efficiency of the third heat exchange zone 260 is increased. Maximum power generation mode: When the temperature of the equipment cooling circulation pipe 100 is higher than the first preset temperature but lower than the preset alarm temperature, the target temperature difference between the cold seawater and the hot cooling medium is controlled to the first target temperature difference to improve the circulation efficiency of the working fluid circulation loop. Frequency modulation mode: When the marine load power suddenly increases, the target temperature difference between the cold seawater and the hot cooling medium is controlled to the first target temperature difference to improve the circulation efficiency of the working fluid circulation loop; when the marine load power suddenly decreases, the target temperature difference between the cold seawater and the hot cooling medium is controlled to the second target temperature difference to reduce the circulation efficiency of the working fluid circulation loop. Emergency mode: When the equipment cooling circulation pipeline 100 exceeds the preset alarm temperature and exceeds the preset range, the equipment will stop running, the first valve will be closed, the second valve will be opened, and the heat exchange efficiency of the third heat exchange zone 260 will be increased.

[0050] The different modes can be switched between each other.

[0051] Under normal operating conditions of the thermal energy utilization system, the temperature of the cooling medium output from the equipment cooling circulation pipe 100 is the first preset temperature, i.e., the temperature of the cooling medium, fresh water, is 40°C. It first flows into the first heat exchange zone 310, i.e., the evaporator. The working fluid in the working fluid circulation loop is ammonia. After absorbing heat, the working fluid evaporates, becoming a high-temperature, high-pressure gaseous working fluid, i.e., working fluid vapor. At the same time, the fresh water in the equipment cooling circulation pipe 100 is cooled to 32°C. The low-pressure working fluid vapor discharged from the turbine enters the second heat exchange zone 320, i.e., the condenser. Here, low-temperature seawater from the low-temperature cooling seawater circulation system cools the working fluid vapor. The temperature of the cold seawater is 10~20°C, causing it to recondense into a liquid working fluid. Depending on the power generation efficiency under different operating conditions, the temperature difference between the high-temperature water entering and leaving the condenser is 5~8°C. The working fluid pump operates within a speed range of 2500r / min~2900r / min. The cooled freshwater then flows into the third heat exchange zone 260, i.e., the plate cooler, where it undergoes secondary heat exchange with the cold seawater from the seawater pipeline 200. The temperature of the cold seawater is 10~20℃, and the freshwater is further cooled to a temperature of 28℃ suitable for use by the equipment 400.

[0052] The preset alarm temperature is set to 42℃.

[0053] For the cooling mode, when the equipment 400 is started or the equipment cooling circulation pipeline 100 reaches the preset alarm temperature, the circulation efficiency of the working fluid circulation loop is reduced to 870r / min~1000r / min to maintain circulation under low power consumption. The speed of the electric submersible pump 210 and the circulation pump 220 is increased, and / or the depth of the electric submersible pump 210 is adjusted. The flow rate of the third valve 232 is reduced, the flow rate of the fourth valve 242 is increased, and the heat exchange efficiency of the third heat exchange zone 260 is increased.

[0054] For the maximum power generation mode, after the equipment 400 has been running stably for a period of time, the grid load is high and the waste heat output is large, the flow rate of the first valve 111 is increased, and the depth of the electric submersible pump 210 is adjusted. The speed of the electric submersible pump 210 and the circulation pump 220 are increased so that the low temperature cold seawater and the high temperature freshwater are at the first target temperature difference, that is, the maximum temperature difference, which is 30℃. The working fluid pump 330 is kept running efficiently within the speed range of 2500r / min~2900r / min.

[0055] In frequency regulation mode, the thermoelectric power generation module is used as a fast-response frequency regulation power source. When the ship's load power suddenly increases, such as when the power grid load on the drilling vessel suddenly increases, the working fluid pump 330 maintains efficient operation within the speed range of 2500r / min to 2900r / min. The depth of the electric submersible pump 210 is adjusted, and the speed of the electric submersible pump 210 and the circulation pump 220 is increased to keep the low-temperature seawater and high-temperature freshwater at the first target temperature difference, i.e., the maximum temperature difference of 30℃, thereby increasing the power generation capacity and supporting the power grid. When the ship's load power suddenly decreases, the power generation efficiency is reduced, which can improve the stability and resilience of the entire ship's power system. The working fluid pump 330 maintains low-efficiency operation within the speed range of 1500r / min to 2000r / min. The depth of the electric submersible pump is adjusted, and / or the speed of the electric submersible pump 210 and the circulation pump 220 is adjusted to keep the low-temperature seawater and high-temperature freshwater at the second target temperature difference, i.e., the temperature difference of 25℃.

[0056] For emergency mode, when the equipment cooling circulation pipeline 100 exceeds the preset alarm temperature of 42℃ and exceeds the preset range by 3℃, i.e., exceeds 45℃, the cooling mode is activated. Alternatively, the speed of the working fluid pump 330 is reduced or the pump is temporarily shut down. The flow rate of the first valve 111 is reduced or the first valve 111 is closed. At the same time, the flow rate of the second valve 121 is increased to be fully open, and cooling is carried out directly through the third heat exchange zone 260. The depth of the electric submersible pump 210 is adjusted, and the speed of the electric submersible pump 210 and the circulation pump 220 is increased. If the cold seawater temperature does not meet the requirements, the cold seawater in the low-temperature seawater tank 250 is checked to see if it meets the requirements. Cold seawater is selectively output through the low-temperature seawater tank 250.

[0057] Understandably, cold seawater can be selectively output through the cryogenic seawater tank 250 in all modes.

[0058] The usage method provided in this application can proactively adapt to different operating conditions and automatically adjust the power generation mode. The multi-mode design is adapted to different operating conditions such as ship equipment startup, stable operation, power grid fluctuations, and emergency failures, and achieves a dynamic balance between power generation efficiency, equipment cooling, and power grid stability. The cooling mode and emergency mode prioritize equipment safety and avoid equipment damage caused by overheating. The maximum power generation mode and frequency regulation mode take into account both energy utilization efficiency and power grid stability, enabling the system to proactively adapt to the dynamic changes in ship operations.

[0059] This application also provides a vessel, including the aforementioned thermal energy utilization system. The vessel can be a deep-water drilling vessel. The control structure of the thermal energy utilization system is integrated with the central control system of the drilling vessel. Operators can monitor the system's operating status in real time in the central control room, switch operating modes, and adjust parameters. The electricity generated by the generator is preferentially supplied to the circulating pump 220 or other equipment 400 on the drilling vessel. Surplus electricity can be stored in the vessel's energy storage device or integrated into the vessel's main power grid. This application realizes on-site recovery of equipment waste heat and on-site utilization of electricity. The stable operation of the system ensures the cooling effect of the drilling vessel's equipment and the stability of the power grid. For deep-water drilling vessels, the acquisition of cold seawater utilizes the operational characteristics of the drilling vessel, eliminating the need for additional dedicated pipelines. This saves the need for dedicated ultra-long cold water pipes and offshore platforms required for traditional ocean thermal energy conversion. By utilizing the drilling vessel's own operational processes to obtain the cold source, the engineering threshold and cost of realizing thermal energy conversion are greatly reduced, improving the energy self-sufficiency and environmental performance of the drilling vessel, and providing support for the safe and efficient conduct of drilling operations.

[0060] In one specific embodiment, the temperature of the hot cooling medium freshwater output by the cooling circulation pipeline 100 of this application is 40°C, and the flow rate is 1000 kg / s. The temperature range of the cold seawater is 10~20°C, with an average of 15°C. The temperature of the hot cooling medium freshwater decreases by 3°C in the evaporator. The gross power generation is calculated as the product of the hot cooling medium freshwater flow rate, the specific heat capacity of the freshwater, and the temperature decrease. Taking the specific heat capacity of water as 4.0 kJ / kg·°C, the calculated gross power generation is 12000 kW. Taking a conservative value of 3% for the actual system efficiency, the gross power generation P_gross = 12000 kW × 3% = 360 kW. In the thermal energy utilization system, the main sources of self-consumption are the electric submersible pump 210, the circulation pump 220, and the working fluid pump 330. The system's self-consumption is 120 kW. Therefore, the static output power is the difference between the gross power generation and the system's self-consumption, which is 240 kW. In the thermal energy utilization system of this application, the equipment cooling circulation pipeline 100 cools the equipment 400 and outputs hot fresh water. The hot fresh water releases heat in the evaporator, then releases heat again in the plate cooler, and then cools the equipment 400 again. Ammonia in the working fluid circulation loop absorbs heat to form a gaseous state, which drives the turbine blades to generate electricity. Then, it releases heat to the cold seawater in the second heat exchange zone 320 and forms a liquid state, utilizing the waste heat of the fresh water to generate electricity. This effectively utilizes waste heat, saves energy, and generates additional electricity while supplying power to the system's own equipment. It provides stable power generation and is suitable for the needs of long-term ship operations.

[0061] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application. Furthermore, unless otherwise specified, the embodiments and features described in the embodiments of this application can be combined with each other.

Claims

1. A thermal energy utilization system, characterized by, The heat energy utilization system comprises: a device cooling circulation pipeline, which comprises an input end for inputting cooling medium and an output end for outputting cooling medium; a seawater pipeline for inputting and outputting cold seawater; a thermoelectric power generation module, which comprises a first heat exchange zone, a second heat exchange zone and a working medium circulation loop; wherein the first heat exchange zone and the second heat exchange zone are arranged in series in the working medium circulation loop, the first heat exchange zone corresponds to heat exchange with the device cooling circulation pipeline, and the second heat exchange zone corresponds to heat exchange with the seawater pipeline; the first heat exchange zone is used for absorbing heat energy of the device cooling circulation pipeline, the second heat exchange zone is used for releasing heat energy to the cold seawater, and the working medium circulation loop is used for circulation of working medium, and the working medium converts energy into electric energy through form conversion in the working medium circulation loop.

2. The thermal energy utilization system of claim 1, wherein: The heat energy utilization system further comprises a third heat exchange zone, and the device cooling circulation pipeline can further exchange heat with the seawater pipeline in the third heat exchange zone; the first heat exchange zone and the third heat exchange zone are used for sequentially exchanging heat with the cooling medium of the device cooling circulation pipeline.

3. The thermal energy utilization system of claim 2, wherein: The seawater pipeline comprises a first pipe section and a second pipe section; the first pipe section is used for absorbing heat in the second heat exchange zone, and the second pipe section absorbs heat in the third heat exchange zone; the first pipe section and the second pipe section are each provided with a flow control valve and a temperature sensor.

4. The thermal energy utilization system of claim 2, wherein: The device cooling circulation pipeline is provided with a bypass pipe, one end of the bypass pipe is connected to the output end of the device cooling circulation pipeline, and the other end of the bypass pipe is connected to a pipe section before the device cooling circulation pipeline inputs the third heat exchange zone.

5. The thermal energy utilization system of claim 4, wherein: A first valve is arranged between an interface of the device cooling circulation pipeline connected with the bypass pipe and a pipe section before the first heat exchange zone of the device cooling circulation pipeline, and / or a second valve is arranged on the bypass pipe.

6. The thermal energy utilization system of claim 1, wherein: The first heat exchange zone comprises an evaporator, the second heat exchange zone comprises a condenser, the working medium circulation loop comprises a working medium pump and a mechanical working mechanism, and working medium circulates in the evaporator, the mechanical working mechanism, the condenser and the working medium pump in sequence; the evaporator is used for absorbing heat of the device cooling circulation pipeline to vaporize liquid working medium, the condenser is used for liquefying gaseous working medium by using the cold seawater, and the mechanical working mechanism is used for converting mechanical energy generated by working of the gaseous working medium into electric energy.

7. The thermal energy utilization system of claim 6, wherein: The heat energy utilization system comprises a control structure, the evaporator and the condenser are each provided with the pressure sensor and the temperature sensor; the control structure is electrically connected with the pressure sensor, the temperature sensor and the working medium pump, and the control structure is used for controlling a rotating speed of the working medium pump according to monitoring data.

8. The thermal energy utilization system of claim 1, wherein: A flow control valve is arranged between the output end of the device cooling circulation pipeline and the first heat exchange zone, and the flow control valve is used for controlling a flow of the cooling medium.

9. A method of using a thermal energy utilization system as defined in claim 5, wherein, The heat energy utilization system comprises: The device cooling circulation pipeline and the seawater pipeline are each provided with a temperature sensor; the temperature of the cooling medium output by the device cooling circulation pipeline is a first preset temperature and is provided with a preset alarm temperature, and the heat energy utilization system comprises the following modes: Cooling mode: when the device starts or the device cooling cycle pipeline reaches the preset alarm temperature, the circulating efficiency of the working medium circulation loop is reduced, and the heat exchange efficiency of the third heat exchange area is increased; Maximum power generation mode: when the temperature of the device cooling circulation pipeline is higher than the first preset temperature and lower than the preset alarm temperature, the target temperature difference between the cold seawater and the cooling medium is controlled to be the first target temperature difference, and the circulating efficiency of the working medium circulation loop is improved; Frequency modulation mode: when the ship load power suddenly rises, the target temperature difference between the cold seawater and the cooling medium is controlled to be the first target temperature difference, and the circulating efficiency of the working medium circulation loop is improved; when the ship load power suddenly drops, the target temperature difference between the cold seawater and the cooling medium is controlled to be the second target temperature difference, and the circulating efficiency of the working medium circulation loop is reduced; Emergency mode: when the device cooling circulation pipeline exceeds the preset alarm temperature and is greater than the preset temperature, the device stops running, the first valve is closed, the second valve is opened, and the heat exchange efficiency of the third heat exchange area is increased.

10. A boat characterised in that, The thermal energy utilization system according to any one of claims 1 to 8.

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