Thermal power generation steam CO2 cooling and liquefying device and using method thereof
By using liquid CO2 cooling liquefaction devices in thermal power plants, the problem of scale deposition in water cooling systems has been solved, achieving automated temperature control and efficient cooling, improving production efficiency, reducing energy consumption and maintenance costs, and expanding the site selection flexibility of thermal power plants.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JIEWEI INTELLIGENT TECHNOLOGY (JIANGSU) CO LTD
- Filing Date
- 2026-03-06
- Publication Date
- 2026-04-24
AI Technical Summary
When thermal power plants use water cooling systems, they need to frequently remove scale, which leads to low production efficiency and dependence on river and lake water sources, increasing energy consumption and maintenance costs. At the same time, water resource extraction has an impact on the ecology.
Liquid CO2 is used as the cooling medium, and the temperature is automatically controlled by a CO2 cooling liquefaction device to avoid scale buildup. The inertness and stability of CO2 are utilized to reduce pipeline corrosion and achieve automated temperature control and circulating cooling.
It does not rely on rivers and lakes, reducing the ecological impact of water resource extraction, lowering the operating costs and energy consumption of purification equipment, improving production efficiency, and reducing equipment failure rate and maintenance frequency.
Smart Images
Figure CN121916684A_ABST
Abstract
Description
Technical Field
[0001] This invention patent relates to the field of cooling technology, specifically to a steam CO2 cooling and liquefaction device for thermal power generation and its usage method. Background Technology
[0002] In modern thermal power plants, the condenser cooling system is used to cool the steam driving the turbine, which requires a large amount of water. Therefore, these plants are often built near rivers and lakes for easy access to water. However, the water in these water sources contains a lot of impurities, and purification before use is an energy-intensive process. Furthermore, the use of water for heat exchange causes scale to form on the inner walls of the cooling system pipes, especially in the condenser where the inner diameter of the tubes is relatively small. As a result, thermal power plants periodically shut down to clean the scale from the inner walls of the condenser tubes, which reduces the plant's production efficiency.
[0003] Therefore, we propose a steam CO2 cooling and liquefaction device for thermal power generation, which can ensure the continuous operation of thermal power plants while avoiding scale buildup on the inner walls of pipelines and condenser tubes. It can also achieve automated temperature control, reduce maintenance and labor costs, and improve work efficiency.
[0004] The purpose of this invention is to provide a steam CO2 cooling and liquefaction device for thermal power generation to solve the problems mentioned in the background art.
[0005] To solve the above-mentioned technical problems, this invention provides the following technical solution: a steam CO2 cooling and liquefaction device for thermal power generation, comprising a liquid CO2 storage tank, a heat exchange unit, a conversion unit, a condenser, and a recovery unit, wherein the number of the heat exchange unit and the conversion unit is at least one; The heat exchange unit includes a shell-and-tube heat exchanger a and a gas-liquid separator. The shell-side input end of the shell-and-tube heat exchanger a is connected to the output end of the liquid CO2 storage tank through a primary conveying pipeline. The shell-side output end of the shell-and-tube heat exchanger a is connected to the input end of the gas-liquid separator through a transfer pipeline a. The output end of the gas-liquid separator is connected to the tube-side input end of the condenser through a secondary conveying pipeline. The conversion unit includes a booster, a temperature controller, and a nozzle arranged sequentially along the CO2 conveying direction on the secondary conveying pipeline. The output end of the nozzle is connected to the input end of the condenser tube. The recovery unit includes at least one gas recovery tank and N recovery components, with the input end connected to the output end of the condenser tube side via a recovery pipeline. The recovery components include a shell-and-tube heat exchanger b and a compressor. The output end of the gas recovery tank is connected to the input ends of the N compressors via a branch pipeline. The input end of the liquid CO2 storage tank is connected to the shell-side output ends of the N shell-and-tube heat exchangers b via a polymerization pipeline. The shell-side input ends of the shell-and-tube heat exchangers b in the same group are connected to the output ends of the compressors via a transfer pipeline b. The primary delivery pipeline and the secondary delivery pipeline located on the input side of the booster are each equipped with a liquid CO2 electrically controlled valve a and a booster delivery pump a in sequence along the CO2 delivery direction. The main pipelines of the recovery pipeline and the diversion pipeline are each equipped with a gaseous CO2 electrically controlled valve a and a gas delivery pump in sequence along the CO2 delivery direction. The branch pipeline of the polymerization pipeline is equipped with a booster delivery pump b. The top of the gas-liquid separator is connected to the input end of the nozzle through a gas delivery pipeline. The gas delivery pipeline is equipped with a gaseous CO2 electrically controlled valve b and an air compressor in sequence along the CO2 delivery direction. The output end of the branch pipeline of the diversion pipeline and the input end of the branch pipeline of the polymerization pipeline are respectively equipped with a gaseous electrically controlled valve c and a liquid electrically controlled valve b. Temperature detectors are installed at the tube-side output ends of the shell-and-tube heat exchanger a, the condenser, and the shell-and-tube heat exchanger b.
[0006] Furthermore, both the booster pump a and the booster pump b are high-pressure shielded pumps.
[0007] Furthermore, pressure gauges are installed on the main pipelines of the shell-and-tube heat exchanger a, the gas-liquid separator, the gas recovery tank, the shell-and-tube heat exchanger b, and the branch pipeline. Pressure relief valves are installed on the main pipelines of the gas-liquid separator, the gas recovery tank, the shell-and-tube heat exchanger b, and the branch pipeline. The pressure gauges and pressure relief valves on the main pipelines of the branch pipeline are arranged sequentially along the CO2 delivery direction and are located on the output end side of the gas pump.
[0008] Furthermore, each of the branch lines of the initial delivery pipeline, gas delivery pipeline, recovery pipeline, and diversion pipeline is equipped with an electric flow regulating valve. The electric flow regulating valve located on the initial delivery pipeline is positioned between the liquid CO2 electric control valve a and the booster delivery pump a. The electric flow regulating valve located on the gas delivery pipeline is positioned between the gaseous CO2 electric control valve b and the air compressor. The electric flow regulating valve located on the recovery pipeline is positioned between the gaseous CO2 electric control valve and the gas delivery pump.
[0009] Furthermore, upper liquid level sensors are installed in the middle of the shell-side inner wall of the shell-and-tube heat exchanger a and the middle of the inner wall of the gas-liquid separator, and lower liquid level sensors are installed in the lower part of the shell-side inner wall of the shell-and-tube heat exchanger a and the lower part of the inner wall of the gas-liquid separator.
[0010] Furthermore, check valves are provided at the output ends of the primary delivery pipeline, transfer pipeline a, secondary delivery pipeline, gas pipeline, recovery pipeline, transfer pipeline b, and polymerization pipeline main pipeline.
[0011] A method for implementing a liquid CO2 condensing steam system based on a steam turbine in a thermal power plant includes the following steps: S1: The high-pressure shielded pump on the initial delivery pipeline draws liquid CO2 from the liquid CO2 storage tank, pressurizes it, and delivers it to the shell-and-tube heat exchanger a for cooling. The gas-liquid mixed state of CO2 is then delivered to the gas-liquid separator via the transfer pipeline a. S2: The high-pressure shielded pump and air compressor on the secondary delivery pipeline respectively extract gaseous CO2 and liquid CO2 from the gas-liquid separator. The gaseous CO2 is pressurized by the air compressor and delivered to the nozzle. The liquid CO2 is further pressurized by the booster and cooled by the temperature controller to become subcritical CO2 and delivered to the nozzle. The subcritical CO2 in the nozzle mixes with the pressurized gaseous CO2 and is converted into a high-pressure gas-solid mixture. It is then injected into the condenser through the output end of the nozzle. The high-pressure gas-solid mixture CO2 exchanges heat with the steam in the shell side of the condenser through the heat exchange tube side and is delivered to the gas recovery tank through the recovery pipeline. S3: The gas pump on the main pipeline of the branch pipeline draws gaseous CO2 from the gas recovery tank and delivers it to the corresponding compressor through one or N branch pipelines for pressurization. The pressurized gaseous CO2 is then delivered to the shell-and-tube heat exchanger b via the transfer pipeline for cooling and conversion into liquid CO2. The high-pressure shielded pump on the branch pipeline of the polymerization pipeline draws liquid CO2 from the shell-and-tube heat exchanger b and delivers it back to the liquid CO2 storage tank through the polymerization pipeline.
[0012] Furthermore, the opening and closing degree of the electric flow regulating valve on the initial delivery pipeline and the operating power of the high-pressure shielded pump are both regulated based on the pressure gauge readings on the shell-and-tube heat exchanger a. The heat exchange power of the shell-and-tube heat exchanger a is regulated based on the temperature readings from the temperature detector at the tube-side output end of the shell-and-tube heat exchanger a. The opening and closing degree of the electric flow regulating valve on the initial delivery pipeline, the operating power of the high-pressure shielded pump, and the heat exchange power of the shell-and-tube heat exchanger a are all regulated based on the triggering of the upper and lower liquid level sensors in the gas-liquid separator.
[0013] Furthermore, the opening and closing degree of the electric flow regulating valve on the primary delivery pipeline, the operating power of the high-pressure shielded pump, the heat exchange power of the shell-and-tube heat exchanger a, the operating power of the high-pressure shielded pump on the secondary delivery pipeline, the operating power of the air compressor, the operating power of the two gas pumps, the opening and closing degree of the electric flow regulating valve on the branch pipeline of the diversion pipeline and the number of openings and closings of the gaseous electric control valve c, the heat exchange power of the shell-and-tube heat exchanger b, the operating power of the compressor, and the operating power of the high-pressure shielded pump on the branch pipeline of the polymerization pipeline and the number of openings and closings of the liquid electric control valve b are all regulated based on the temperature detection value of the condenser tube output end temperature detector 8.
[0014] The beneficial effects achieved by this invention patent are as follows: Using liquid CO2 instead of traditional cooling water as the cooling medium eliminates the need to rely on rivers and lakes for power plant construction, breaks the geographical limitations of water intake, expands the flexibility of power plant site selection, avoids the purification requirements caused by impurities in river and lake water, eliminates the high energy consumption of water pretreatment, significantly reduces the operating cost and energy consumption of purification equipment, and avoids the ecological impact of water resource extraction.
[0015] Liquid CO2 leaves no impurities during circulation and, as a cooling medium, does not form scale on the inner walls of pipelines and condenser tubes. This solves the scaling problem of traditional water cooling systems at its source, eliminating the need for periodic shutdowns to clean scale from the condenser tubes, avoiding production interruptions caused by shutdowns for maintenance, ensuring continuous and stable operation of thermal power plants, and significantly improving production efficiency.
[0016] The system is equipped with temperature detectors, sensors, and an external central control platform to achieve automated temperature control and closed-loop regulation of the cooling process. It eliminates the need for frequent manual intervention, reducing labor costs. Furthermore, due to the absence of scaling and minimal wear from impurities, the failure rate of system pipelines and equipment is significantly reduced, decreasing the frequency and cost of equipment maintenance and further alleviating the operational and maintenance burden of thermal power plants.
[0017] Liquid CO2, as an inert medium, is chemically stable and will not corrode pipelines or the inner walls of condenser tubes. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the structure of a steam CO2 cooling and liquefaction device for thermal power generation in the embodiment; Figure 2 As in the embodiments Figure 3 This is a flowchart illustrating the usage method of a steam CO2 cooling and liquefaction device for thermal power generation, as described in this embodiment. Detailed Implementation
[0019] The present invention will be further described below with reference to the accompanying drawings. Example
[0020] like Figure 1-2 As shown, this embodiment discloses a steam CO2 cooling and liquefaction device for thermal power generation, including: a liquid CO2 storage tank 1, a heat exchange unit 2, a conversion unit 3, a condenser 4, and a recovery unit 5, wherein the number of heat exchange unit 2 and conversion unit 3 is at least one; The heat exchange unit 2 includes a shell-and-tube heat exchanger a21 and a gas-liquid separator 22. The shell-side input end of the shell-and-tube heat exchanger a21 is connected to the output end of the liquid CO2 storage tank 1 through the primary conveying pipeline 11. The shell-side output end of the shell-and-tube heat exchanger a21 is connected to the input end of the gas-liquid separator 22 through the transfer pipeline a23. The output end of the gas-liquid separator 22 is connected to the tube-side input end of the condenser 4 through the secondary conveying pipeline 24. The conversion unit 3 includes a booster 31, a temperature controller 32 and a nozzle 33 arranged sequentially on the secondary conveying pipeline 24 along the CO2 conveying direction. The output end of the nozzle 33 is connected to the tube input end of the condenser 4. The recovery unit 5 includes at least one gas recovery tank 51 whose input end is connected to the tube-side output end of the condenser 4 via a recovery pipeline 54, and N recovery components. The recovery components include shell-and-tube heat exchangers b52 and compressors 53. The output end of the gas recovery tank 51 is connected to the input ends of the N compressors 53 via a branch pipeline 55. The input end of the liquid CO2 storage tank 1 is connected to the shell-side output ends of the N shell-and-tube heat exchangers b52 via a polymerization pipeline 56. The shell-side input ends of the shell-and-tube heat exchangers b52 in the same group are connected to the output ends of the compressors 53 via a transfer pipeline b57. The primary delivery pipeline 11 and the secondary delivery pipeline 24 located at the input section of the booster 31 are each equipped with a liquid CO2 electrically controlled valve a6 and a booster delivery pump a61 sequentially along the CO2 delivery direction. The main pipelines of the recovery pipeline 54 and the diversion pipeline 55 are each equipped with a gaseous CO2 electrically controlled valve a62 and a gas delivery pump 63 sequentially along the CO2 delivery direction. A booster delivery pump b64 is installed on the branch pipeline of the polymerization pipeline 56. The gas-liquid separator 22... The top end is connected to the input end of the nozzle 33 via the gas transmission pipeline 25. Along the CO2 delivery direction, the gas transmission pipeline 25 is sequentially equipped with a gaseous CO2 electric control valve b65 and an air compressor 66. The output end of the branch pipeline of the diversion pipeline 55 and the input end of the branch pipeline of the polymerization pipeline 56 are respectively equipped with a gaseous electric control valve c58 and a liquid electric control valve b59. Temperature detectors 8 are installed at the tube-side output ends of the shell-and-tube heat exchanger a21, the condenser 4 and the shell-and-tube heat exchanger b52. Specifically, such as Figure 2 As shown, the vertical end of nozzle 33 is connected to the output end of secondary conveying pipeline 24, and the side end of nozzle 33 is connected to the output end of gas conveying pipeline 25. Subcritical CO2 enters nozzle 33 through the output end of secondary conveying pipeline 24. At the same time, gaseous CO2 enters nozzle 33 through the output end of gas pipeline 25. Subcritical CO2 and gaseous CO2 mix at the output end of nozzle 33, and the high-pressure gas-solid mixture of CO2 is ejected from the output end of nozzle 33 into condenser 4 for heat exchange.
[0021] Furthermore, both booster pump a61 and booster pump b64 are high-pressure shielded pumps. The high-pressure shielded pumps can boost pressure while ensuring the delivery of liquid CO2.
[0022] Furthermore, such as Figure 1-2As shown, pressure gauges 67 are installed on the main pipelines of shell-and-tube heat exchanger a21, gas-liquid separator 22, gas recovery tank 51, shell-and-tube heat exchanger b52, and branch line 55. Pressure relief valves 68 are installed on the main pipelines of gas-liquid separator 22, gas recovery tank 51, shell-and-tube heat exchanger b52, and branch line 55. The pressure gauges 67 and pressure relief valves 68 on the main pipeline of branch line 55 are arranged sequentially along the CO2 delivery direction and located at the output end of gas pump 63. The pressure gauges 67 detect the pressure value in real time. When the pressure gauges 67 detect that the pressure value in any equipment or pipeline exceeds the preset limit and the system cannot be controlled, the corresponding pressure relief valve 68 opens and releases pressure, while activating another heat exchange unit 2 and conversion unit 3 to alleviate the system pressure.
[0023] Furthermore, such as Figure 1-2 As shown, electric flow regulating valves 69 are installed on the branch lines of the initial delivery pipeline 11, the gas delivery pipeline 25, the recovery pipeline 54, and the diversion pipeline 55. The electric flow regulating valve 69 on the initial delivery pipeline 11 is located between the liquid CO2 electric control valve a6 and the booster delivery pump a61. The electric flow regulating valve 69 on the gas delivery pipeline 25 is located between the gas CO2 electric control valve b65 and the air compressor 66. The electric flow regulating valve 69 on the recovery pipeline 54 is located between the gas CO2 electric control valve 62 and the gas delivery pump 63.
[0024] Furthermore, such as Figure 1-2 As shown, upper liquid level sensors 7 are installed in the middle of the shell-side inner wall of the shell-and-tube heat exchanger a21 and the middle of the inner wall of the gas-liquid separator 22, and lower liquid level sensors 71 are installed in the lower part of the shell-side inner wall of the shell-and-tube heat exchanger a21 and the lower part of the inner wall of the gas-liquid separator 22.
[0025] Furthermore, such as Figure 1-2 As shown, check valves 691 are installed at the output ends of the primary conveying pipeline 11, the transfer pipeline a23, the secondary conveying pipeline 24, the gas transmission pipeline 25, the recovery pipeline 54, the transfer pipeline b57, and the main pipeline of the polymerization pipeline 56. The design of the check valves 691 prevents gaseous and liquid CO2 from flowing back along the pipeline.
[0026] Specifically, the booster 31, temperature controller 32, temperature detector 8, compressor 53, liquid CO2 electric control valve a6, booster delivery pump a61, gaseous CO2 electric control valve a62, air pump 63, booster delivery pump b64, gaseous CO2 electric control valve b65, air compressor 66, gaseous electric control valve c58, liquid electric control valve b59, pressure gauge 67, pressure relief valve 68, electric flow regulating valve 69, upper liquid level sensor 7, and lower liquid level sensor 71 are all connected to an external central control platform (not shown in the figure).
[0027] Specifically, the tube-side inlet and outlet of shell-and-tube heat exchanger a21 and shell-and-tube heat exchanger b52 are both connected to an external heat exchange system (not shown in the figure). Example
[0028] like Figure 3 As shown in Embodiment 2, a method for using a liquid CO2 condensing steam system based on a steam turbine in a thermal power plant is disclosed, including the following steps: S1: The high-pressure shielded pump on the initial delivery pipeline 11 draws liquid CO2 from the liquid CO2 storage tank 1, pressurizes it, and delivers it to the shell-and-tube heat exchanger a21 for cooling. The gas-liquid mixed state CO2 is then delivered to the gas-liquid separator 22 through the transfer pipeline a23. S2: The high-pressure shielded pump and air compressor 66 on the secondary conveying pipeline 24 respectively extract gaseous CO2 and liquid CO2 from the gas-liquid separator 22. The gaseous CO2 is pressurized by the air compressor 66 and conveyed to the nozzle 33. The liquid CO2 is further pressurized by the booster 31 and cooled by the temperature controller 32 to become subcritical CO2 and is conveyed to the nozzle 33. The subcritical CO2 in the nozzle 33 mixes with the pressurized gaseous CO2 and is converted into a high-pressure gas-solid mixture. It is then injected into the condenser 4 through the output end of the nozzle 33. The high-pressure gas-solid mixture CO2 exchanges heat with the steam in the shell side of the condenser 4 through the heat exchange tube side and is then conveyed to the gas recovery tank 51 by the recovery pipeline 54. S3: The gas pump 63 on the main line of the branch line 55 draws gaseous CO2 from the gas recovery tank 51 and delivers it to the corresponding compressor 53 through one or N branch lines for pressurization. The pressurized gaseous CO2 is then delivered to the shell-and-tube heat exchanger b52 through the transfer line b57 for cooling and conversion into liquid CO2. The high-pressure shielded pump on the branch line of the polymerization line 56 draws liquid CO2 from the shell-and-tube heat exchanger b52 and delivers it back to the liquid CO2 storage tank 1 through the polymerization line 56.
[0029] Furthermore, the opening and closing degree of the electric flow regulating valve 69 on the initial delivery pipeline 11 and the operating power of the high-pressure shielded pump are both regulated based on the detection value of the pressure gauge 67 on the shell-and-tube heat exchanger a21. The heat exchange power of the shell-and-tube heat exchanger a21 is regulated based on the detection value of the temperature detector 8 at the tube-side output end of the shell-and-tube heat exchanger a21. The opening and closing degree of the electric flow regulating valve 69 on the initial delivery pipeline 11, the operating power of the high-pressure shielded pump, and the heat exchange power of the shell-and-tube heat exchanger a21 are all regulated based on the triggering of the upper liquid level sensor 7 and the lower liquid level sensor 71 in the gas-liquid separator 22. When the pressure gauge 67 of the shell-and-tube heat exchanger a21 exceeds the predetermined threshold, the external central control platform controls the electric flow regulating valve 69 and the high-pressure shielded pump on the initial delivery pipeline 11 to reduce the opening degree and operating power, and vice versa. When the temperature detected by the temperature detector 8 at the tube side output end of the shell-and-tube heat exchanger a21 exceeds the predetermined threshold, the external central control platform controls the shell-and-tube heat exchanger a21 to increase the heat exchange power, and vice versa. When the lower liquid level sensor 71 in the gas-liquid separator 22 is triggered, the external central control platform controls the electric flow regulating valve 69 and the high-pressure shielded pump on the initial conveying pipeline 11, as well as the shell-and-tube heat exchanger a21, to reduce their opening degree, operating power, and heat exchange power. When the upper liquid level sensor 7 in the gas-liquid separator 22 is triggered, the power is reduced accordingly. The heat exchange power weighting ratio of shell-and-tube heat exchanger a21 is: the triggering of the upper liquid level sensor 7 and the lower liquid level sensor 71 in the gas-liquid separator 22 > the detection value of the temperature detector 8 of shell-and-tube heat exchanger a21. The weighting ratio of the opening and closing degree of the electric flow regulating valve 69 on the initial delivery pipeline 11 to the operating power of the high-pressure shielded pump: the triggering of the upper liquid level sensor 7 and the lower liquid level sensor 71 in the gas-liquid separator 22 > the detection value of the pressure gauge 67 on the shell-and-tube heat exchanger a21.
[0030] Furthermore, the opening and closing degree of the electric flow regulating valve 69 on the primary delivery pipeline 11, the operating power of the high-pressure shielded pump, the heat exchange power of the shell-and-tube heat exchanger a21, the operating power of the high-pressure shielded pump on the secondary delivery pipeline 24, the operating power of the air compressor 66, the operating power of the two air pumps 63, the opening and closing degree of the electric flow regulating valve 69 on the branch pipeline of the diversion pipeline 55, the number of openings and closings of the gaseous electric control valve c58, the heat exchange power of the shell-and-tube heat exchanger b52, the operating power of the compressor 53, and the operating power of the high-pressure shielded pump and the number of openings and closings of the liquid electric control valve b59 on the branch pipeline of the polymerization pipeline 56 are all regulated based on the temperature detection value of the temperature detector 8 at the tube-side output end of the condenser 4. When the temperature detected by the temperature detector 8 at the output end of the condenser tube exceeds the predetermined threshold, the external central control platform controls the opening degree of the electric flow regulating valve 69 on the primary delivery pipeline 11 and the operating power of the high-pressure shielded pump, the heat exchange power of the shell-and-tube heat exchanger a21, the operating power of the high-pressure shielded pump on the secondary delivery pipeline 24, the operating power of the air compressor 66, the operating power of the two air pumps 63, the opening degree of the electric flow regulating valve 69 on the branch pipeline of the diversion pipeline 55 and the number of openings of the gaseous electric control valve c58, the heat exchange power of the shell-and-tube heat exchanger b52, the operating power of the compressor 53, and the operating power of the high-pressure shielded pump and the number of openings of the liquid electric control valve b59 on the branch pipeline of the polymerization pipeline 56 to increase, and vice versa. The weighting ratio of the temperature detection value of the temperature detector 8 at the output end of the condenser tube 4 is greater than the triggering weighting ratio of the upper liquid level sensor 7 and the lower liquid level sensor 71 in the gas-liquid separator 22. Preferably, the opening and closing of the gaseous electric control valve c58 is a prerequisite for the start / stop of the electric flow regulating valve 69 on the corresponding branch line 55, the corresponding compressor 53, the corresponding shell-and-tube heat exchanger b52, and the corresponding high-pressure shielded pump and the corresponding liquid electric control valve b59 on the branch line 56. When the gaseous solenoid valve c58 is open, the external central control platform controls the electric flow regulating valve 69 on the corresponding branch pipeline 55 to run, and the corresponding compressor 53, the corresponding shell-and-tube heat exchanger b52, and the corresponding high-pressure shielded pump and the corresponding liquid solenoid valve b59 on the polymer pipeline 56 to start. Conversely, it can be kept closed. The weighting ratio of the start / stop of the electric flow regulating valve 69, compressor 53, shell-and-tube heat exchanger b52 on the flow line 55 branch line and the corresponding high-pressure shielded pump and corresponding liquid electric control valve b59 on the polymerization line 56 branch line is: the opening and closing of gaseous electric control valve c58 > the detection value of temperature detector 8. Preferably, the triggering of the upper liquid level sensor 7 and the lower liquid level sensor 71 on the shell-and-tube heat exchanger b52 is a prerequisite for the start / stop of the corresponding high-pressure shielded pump and the corresponding liquid electro-hydraulic valve b59 on the branch pipeline of the polymerization pipeline 56. When the upper liquid level sensor 7 on the shell-and-tube heat exchanger b52 is triggered, the corresponding booster pump and the corresponding liquid electro-hydraulic valve b59 on the polymer pipeline 56 branch line are activated; otherwise, they remain closed. The weighting ratio of the start / stop of the high-pressure shielded pump and the liquid solenoid valve b59 on the polymer pipeline 56 is: triggering of the upper liquid level sensor 7 and the lower liquid level sensor 71 on the shell-and-tube heat exchanger b52 > opening and closing of the gas solenoid valve c58.
[0031] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. A steam CO2 cooling and liquefaction device for thermal power generation, characterized in that: It includes a liquid CO2 storage tank (1), a heat exchange unit (2), a conversion unit (3), a condenser (4), and a recovery unit (5), wherein the number of heat exchange units (2) and conversion units (3) is at least one; The heat exchange unit (2) includes a shell-and-tube heat exchanger a (21) and a gas-liquid separator (22). The shell-side input end of the shell-and-tube heat exchanger a (21) is connected to the output end of the liquid CO2 storage tank (1) through the primary section conveying pipeline (11). The shell-side output end of the shell-and-tube heat exchanger a (21) is connected to the input end of the gas-liquid separator (22) through the transfer pipeline a (23). The output end of the gas-liquid separator (22) is connected to the tube-side input end of the condenser (4) through the secondary section conveying pipeline (24). The conversion unit (3) includes a booster (31), a temperature controller (32) and a nozzle (33) arranged sequentially on the secondary conveying pipeline (24) along the CO2 conveying direction. The output end of the nozzle (33) is connected to the tube input end of the condenser (4). The recovery unit (5) includes at least one gas recovery tank (51) whose input end is connected to the tube-side output end of the condenser (4) via a recovery pipeline (54) and N recovery components. The recovery components include shell-and-tube heat exchangers b (52) and compressors (53). The output end of the gas recovery tank (51) is connected to the input ends of N compressors (53) via a diversion pipeline (55). The input end of the liquid CO2 storage tank (1) is connected to the shell-side output ends of N shell-and-tube heat exchangers b (52) via a polymerization pipeline (56). The shell-side input ends of the shell-and-tube heat exchangers b (52) in the same group are connected to the output ends of the compressors (53) via a transfer pipeline b (57). The primary delivery pipeline (11) and the secondary delivery pipeline (24) located on the input side of the booster (31) are each equipped with a liquid CO2 electrically controlled valve a (6) and a booster delivery pump a (61) in sequence along the CO2 delivery direction. The main pipelines of the recovery pipeline (54) and the diversion pipeline (55) are each equipped with a gaseous CO2 electrically controlled valve a (62) and a gas delivery pump (63) in sequence along the CO2 delivery direction. A booster delivery pump b (64) is installed on the branch pipeline of the polymerization pipeline (56). The gas-liquid separator (22)... The top end is connected to the input end of the nozzle (33) through the gas transmission pipeline (25). The gas transmission pipeline (25) is sequentially equipped with a gaseous CO2 electric control valve b (65) and an air compressor (66) along the CO2 transmission direction. The output end of the branch pipeline of the diversion pipeline (55) and the input end of the branch pipeline of the aggregation pipeline (56) are respectively equipped with a gaseous electric control valve c (58) and a liquid electric control valve b (59). The tube-side output end of the shell-and-tube heat exchanger a (21), the condenser (4) and the shell-and-tube heat exchanger b (52) is equipped with a temperature detector (8).
2. The steam CO2 cooling and liquefaction device for thermal power generation according to claim 1, characterized in that: Both the booster pump a (61) and the booster pump b (64) are high-pressure shielded pumps.
3. The steam CO2 cooling and liquefaction device for thermal power generation according to claim 2, characterized in that: Pressure gauges (67) are installed on the main lines of the shell heat exchanger a (21), gas-liquid separator (22), gas recovery tank (51), shell-and-tube heat exchanger b (52) and the branch line (55). Pressure relief valves (68) are installed on the main lines of the gas-liquid separator (22), gas recovery tank (51), shell-and-tube heat exchanger b (52) and the branch line (55). The pressure gauges (67) and pressure relief valves (68) on the main line of the branch line (55) are arranged sequentially along the CO2 delivery direction and are located on the output side of the gas pump (63).
4. The steam CO2 cooling and liquefaction device for thermal power generation according to claim 3, characterized in that: Electric flow regulating valves (69) are installed on the branch lines of the initial delivery pipeline (11), gas delivery pipeline (25), recovery pipeline (54) and diversion pipeline (55). The electric flow regulating valve (69) on the initial delivery pipeline (11) is located between the liquid CO2 electric control valve a (6) and the booster delivery pump a (61). The electric flow regulating valve (69) on the gas delivery pipeline (25) is located between the gas CO2 electric control valve b (65) and the air compressor (66). The electric flow regulating valve (69) on the recovery pipeline (54) is located between the gas CO2 electric control valve (62) and the gas delivery pump (63).
5. A steam CO2 cooling and liquefaction device for thermal power generation according to claim 4, characterized in that: Upper liquid level sensors (7) are provided in the middle of the shell side inner wall of the shell-and-tube heat exchanger a (21) and the middle of the inner wall of the gas-liquid separator (22). Lower liquid level sensors (71) are provided in the lower part of the shell side inner wall of the shell-and-tube heat exchanger a (21) and the lower part of the inner wall of the gas-liquid separator (22).
6. The steam CO2 cooling and liquefaction device for thermal power generation according to claim 5, characterized in that: Check valves (691) are provided at the output ends of the primary delivery pipeline (11), the transfer pipeline a (23), the secondary delivery pipeline (24), the gas pipeline (25), the recovery pipeline (54), the transfer pipeline b (57), and the main pipeline of the polymerization pipeline (56).
7. The method of using the steam CO2 cooling and liquefaction device for thermal power generation according to claim 6, characterized in that: Includes the following steps: S1: The high-pressure shielded pump on the initial section of the conveying pipeline (11) draws liquid CO2 from the liquid CO2 storage tank (1), pressurizes it, and conveys it to the shell-and-tube heat exchanger a (21) for cooling. It then conveys the gas-liquid mixed state CO2 to the gas-liquid separator (22) through the transfer pipeline a (23). S2: The high-pressure shielded pump and air compressor (66) on the secondary conveying pipeline (24) respectively extract gaseous CO2 and liquid CO2 from the gas-liquid separator (22). The gaseous CO2 is pressurized by the air compressor (66) and conveyed to the nozzle (33). The liquid CO2 is further pressurized by the booster (31) and cooled by the temperature controller (32) to become subcritical CO2 and conveyed to the nozzle (33). The subcritical CO2 in the nozzle (33) mixes with the pressurized gaseous CO2 and is converted into a high-pressure gas-solid mixture state. It is then injected into the condenser (4) through the output end of the nozzle (33). The high-pressure gas-solid mixture CO2 exchanges heat with the steam in the shell side of the condenser (4) through the heat exchange tube side and is then conveyed to the gas recovery tank (51) by the recovery pipeline (54). S3: The gas pump (63) on the main pipeline of the branch pipeline (55) extracts gaseous CO2 from the gas recovery tank (51) and delivers it to the corresponding compressor (53) through one or N branch pipes for pressurization. The pressurized gaseous CO2 is then delivered to the shell-and-tube heat exchanger b (52) through the transfer pipeline b (57) for cooling and conversion into liquid CO2. The high-pressure shielded pump on the branch pipeline of the polymerization pipeline (56) extracts liquid CO2 from the shell-and-tube heat exchanger b (52) and delivers it back to the liquid CO2 storage tank (1) through the polymerization pipeline (56).
8. The method of using a steam CO2 cooling and liquefaction device for thermal power generation according to claim 1, characterized in that: The opening and closing degree of the electric flow regulating valve (69) on the initial delivery pipeline (11) and the operating power of the high-pressure shielded pump are both regulated based on the pressure gauge (67) detected on the shell-and-tube heat exchanger a (21). The heat exchange power of the shell-and-tube heat exchanger a (21) is regulated based on the temperature detector (8) detected at the tube-side output end of the shell-and-tube heat exchanger a (21). The power output and the heat exchange power of the shell-and-tube heat exchanger a (21) are both regulated based on the triggering of the upper liquid level sensor (7) and the lower liquid level sensor (71) in the gas-liquid separator (22). The weight ratio of the upper liquid level sensor (7) and the lower liquid level sensor (71) in the gas-liquid separator (22) is greater than the weight ratio of the pressure detection value of the pressure gauge (67) on the shell-and-tube heat exchanger a (21) and the weight ratio of the temperature detection value of the temperature detector (8) at the tube end of the shell-and-tube heat exchanger a (21).
9. The method of using the steam CO2 cooling and liquefaction device for thermal power generation according to claim 1, characterized in that: The opening and closing degree of the electric flow regulating valve (69) on the primary delivery pipeline (11) and the operating power of the high-pressure shielded pump, the heat exchange power of the shell-and-tube heat exchanger a (21), the operating power of the high-pressure shielded pump on the secondary delivery pipeline (24), the operating power of the air compressor (66), the operating power of the two air pumps (63), the opening and closing degree of the electric flow regulating valve (69) on the branch pipeline of the diversion pipeline (55) and the number of openings and closings of the gaseous electric control valve c (58), and the heat exchange power of the shell-and-tube heat exchanger b (52) are all measured. The operating power of the compressor (53), the operating power of the high-pressure shielded pump on the branch line of the polymer pipeline (56), and the number of opening and closing of the liquid electronic control valve b (59) are all regulated based on the temperature detection value of the condenser (4) tube end output instrument (8). The weight ratio of the temperature detection value of the condenser (4) tube end output instrument (8) is greater than the heat exchange power of the shell-and-tube heat exchanger a (21). The weight ratio of the upper liquid level sensor (7) and the lower liquid level sensor (71) in the gas-liquid separator (22) is also regulated.