Lean and rich liquid storage tank and carbon capture power generation system

Abstract

The utility model discloses a rich and lean solution storage tank and a carbon capture power generation system, and the rich and lean solution storage tank comprises a lean solution bin used for storing lean solution; the rich liquid bin is used for storing rich liquid, and the barren liquid and the rich liquid are CO2 absorbents in different states; the at least one empty bin is arranged between the barren liquor bin and the rich liquor bin and is used for adjusting the volume distribution of the barren liquor bin and the rich liquor bin; wherein when the load of the power system is kept unchanged, the volume distribution of the barren liquor bin and the rich liquor bin is kept unchanged; when the power load is increased, rich liquor is replaced through the empty bin and flows into the rich liquor bin, and barren liquor flows out of the barren liquor bin; and when the power load is reduced, the barren liquor is replaced through the empty bin and flows into the barren liquor bin, and the rich liquor flows out of the rich liquor bin. According to the utility model, the problems of huge volume and low space utilization rate of the traditional double storage tanks in the carbon capture power generation system can be solved.

Description

Technical Field

[0001] This utility model relates to the fields of electricity, CO2 capture technology and energy storage technology, and in particular to a lean liquid storage tank and a carbon capture power generation system. Background Technology

[0002] This section is intended to provide background or context for the embodiments of the present invention set forth in the claims. The description herein is not an admission that it is prior art simply because it is included in this section.

[0003] As the proportion of renewable energy in electricity continues to increase, the security and stability of the power system will become more prominent. Due to the discontinuous and unstable nature of renewable energy sources, primarily wind and solar power, fluctuations in energy production and user load on the consumption side will overlap, posing unprecedented challenges to the safe and stable operation of the power grid. Utilizing the controllable characteristics of coal-fired power plants for peak shaving to offset the impact of renewable energy fluctuations is one approach to addressing this challenge.

[0004] Meanwhile, coal-fired power plants emit CO2 during power generation, and deploying CCUS (Chemical Enzyme-Based Gas) technology can further reduce CO2 emissions. Among various capture technologies, chemical absorption CO2 capture is a mature process and is currently the only CO2 capture technology that can be widely deployed commercially. In coal-fired power plants equipped with chemical absorption processes, the CO2 capture unit both extracts steam from the turbines and captures CO2 from the flue gas after desulfurization and denitrification treatment. The CO2 capture unit is directly linked to the coal-fired power plant and participates in peak shaving for the plant.

[0005] Carbon capture (CCF) coal-fired power plants equipped with chemical absorption processes possess three functions: power generation, decarbonization, and peak shaving. However, the coupling relationship between the CCF unit and the power generation unit is complex, hindering the effective functioning of the coupled system. This is mainly due to the following aspects: In power generation, the problem of stable combustion during low-load boiler operation remains unresolved. Furthermore, the CCF unit extracts steam from the power plant's turbines, leading to turbine unit load reduction and resulting in turbine efficiency and power generation losses. In decarbonization, the reduced boiler load reduces the total flue gas volume and CO2 concentration, causing the CCF unit's absorption towers to operate at reduced loads, limiting the large absorption capacity of these towers. In peak shaving, the actual peak shaving depth / rate is primarily determined by the boiler's load variation depth / rate and the CCF unit's steam extraction rate / rate. The differences in load variation and dynamic characteristics between the power generation and CCF units complicate the design of load variation operation control that balances power generation efficiency, carbon capture rate, and peak shaving capability.

[0006] Currently, there is relatively little research on the flexibility modification of carbon capture power generation systems. Exploring the design of carbon capture power generation systems (including lean and rich liquid storage tanks) that can simultaneously achieve high efficiency, low carbon emissions, and flexibility is of great practical significance. Utility Model Content

[0007] This utility model embodiment provides a lean-rich liquid storage tank to solve the problems of large volume and low space utilization of traditional dual storage tanks in carbon capture power generation systems, including:

[0008] A lean solution tank is used to store lean solution.

[0009] The rich solution tank is used to store the rich solution, while the lean solution and rich solution are CO2 absorbents in different states.

[0010] At least one empty compartment is provided between the lean liquid compartment and the rich liquid compartment, which is used to adjust the volume distribution between the lean liquid compartment and the rich liquid compartment.

[0011] Specifically, when the power system load remains constant, the volume distribution between the lean liquid tank and the rich liquid tank remains constant; when the power load increases, the rich liquid is replaced by the empty tank and flows into the rich liquid tank, while the lean liquid flows out of the lean liquid tank; when the power load decreases, the lean liquid is replaced by the empty tank and flows into the lean liquid tank, while the rich liquid flows out of the rich liquid tank.

[0012] This utility model provides a carbon capture power generation system to solve the problems of large volume and low space utilization in traditional dual-tank systems, including: a low-carbon combustion unit, a power generation decarbonization unit and a lean and rich liquid storage tank that are interconnected.

[0013] The low-carbon combustion unit is used to: burn carbon-containing fuels, remove CO2 from flue gas, and generate steam;

[0014] The power generation decarbonization unit is used to: generate electricity using steam and remove CO2 from the CO2 absorbent;

[0015] The lean and rich liquid storage tank is used to store CO2 absorbent.

[0016] In this embodiment of the utility model, the integrated design can effectively reduce the volume of lean and rich liquid storage tanks and improve space utilization. The empty tank design can achieve flexible distribution of lean and rich liquids during peak-shaving operation, thereby improving the economy and feasibility of the entire carbon capture and power generation system. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0018] Figure 1 This is a schematic diagram of the structure of the lean and rich liquid storage tank in the embodiment of this utility model;

[0019] Figure 2 This is a schematic diagram of the carbon capture and power generation system in an embodiment of this utility model;

[0020] Figure 3 This is a schematic diagram of the replacement of lean and rich liquids when the power load increases in an embodiment of this utility model;

[0021] Figure 4 This is a schematic diagram of the replacement of lean and rich liquids when the power load is reduced in an embodiment of this utility model;

[0022] Figure 5 This is a schematic diagram of the structure of the partition-type lean and rich liquid storage tank in this utility model embodiment;

[0023] Figure 6 This is a schematic diagram illustrating the changes in the lean and rich liquids when the power load increases in an embodiment of this utility model.

[0024] Figure 7 This is a schematic diagram illustrating the changes in the rich and poor liquids when the power load decreases in an embodiment of this utility model. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the embodiments of this utility model will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments of this utility model and their descriptions are used to explain this utility model, but are not intended to limit this utility model.

[0026] To address the aforementioned problems, this utility model proposes an integrated lean-rich liquid storage tank, which comes in two forms: a compartmentalized lean-rich liquid storage tank and a baffled lean-rich liquid storage tank. Figure 1 This is a schematic diagram of the structure of the lean and rich liquid storage tank in an embodiment of this utility model. Figure 1 The corresponding compartmentalized lean and rich liquid storage tank 300 is used in a carbon capture and power generation system, including: an integrated lean liquid tank 10, a rich liquid tank 20, and at least one empty tank 30 located between the lean liquid tank and the rich liquid tank.

[0027] The lean liquid tank 10, the rich liquid tank 20, and the empty tank 30 are all equipped with independent inlet and outlet ports;

[0028] The lean solution tank 10 is used to store lean solution;

[0029] The rich liquid tank 20 is used to store the rich liquid, while the lean liquid and rich liquid are CO2 absorbents in different states.

[0030] Empty compartment 30, used to adjust the volume distribution between the lean and rich liquid compartments;

[0031] Specifically, when the power system load remains constant, the volume distribution between the lean liquid tank 10 and the rich liquid tank 20 remains constant; when the power load increases, the rich liquid is replaced by the empty tank 30 and flows into the rich liquid tank 20, while the lean liquid flows out of the lean liquid tank 10; when the power load decreases, the lean liquid is replaced by the empty tank 30 and flows into the lean liquid tank 10, while the rich liquid flows out of the rich liquid tank 20.

[0032] The aforementioned liquid-rich and liquid-poor storage tanks decouple the capture process, and reconstruct the low-carbon combustion unit and power generation decarbonization unit of the carbon capture power generation system.

[0033] The lean and rich liquid storage tank adopts an integrated design method, with lean and rich liquids stored in the same storage device. The lean liquid and rich liquid tanks of the lean and rich liquid storage tank can be synchronously and reversely adjusted through structures such as partitions or movable baffles, thereby reducing the tank volume, improving space utilization, and achieving flexible peak-shaving operation.

[0034] The lean solution storage capacity and the rich solution storage capacity have the characteristic of synchronous and inverse changes. That is, when the demand for rich solution storage increases, the demand for lean solution storage will decrease by the same amount, and vice versa. In addition, since the lean solution and the rich solution have the same composition, only the amount of CO2 they carry is different, a small amount of leakage between the stored lean solution and the rich solution will not seriously affect the storage function.

[0035] Figure 2 This is a schematic diagram of the carbon capture and power generation system in an embodiment of the present invention. The system includes a low-carbon combustion unit 100, a power generation and decarbonization unit 200, and a lean and rich liquid storage tank 300 that are interconnected.

[0036] The low-carbon combustion unit 100 is used to: burn carbon-containing fuels, remove CO2 from flue gas, and generate steam;

[0037] The power generation decarbonization unit 200 is used to: generate electricity using steam and remove CO2 from the CO2 absorbent;

[0038] The lean and rich liquid storage tank 300 is used to store CO2 absorbent.

[0039] The low-carbon combustion unit 100 includes a boiler 1 and an absorption tower 2, and the power generation decarbonization unit 200 includes a turbine 3 and a desorption tower 4.

[0040] The steam mentioned above is high-temperature steam. Figure 1 This describes the empty condition of the compartmented lean and rich liquid storage tank when the power load remains constant. When the power load remains constant, the steam extraction rate of the desorption tower and the production of lean and rich liquids remain stable, ensuring the stable operation of the absorption tower and desorption tower under non-peak-shaving conditions. Figure 3 This is a schematic diagram of the replacement of lean and rich liquids when the power load increases in this embodiment of the present invention. When the power load increases, the rich liquid in the compartmented lean and rich liquid storage tank is replaced by the empty compartment and flows smoothly into the rich liquid compartment to ensure that the rich liquid gets more storage space, thereby meeting the coordinated operation of the absorption tower and desorption tower under high power load. Figure 4 This is a schematic diagram of lean and rich liquid replacement in an embodiment of the present invention when the power load decreases. When the power load decreases, the lean liquid in the compartmentalized storage tank is replaced by empty compartment into the lean liquid tank, ensuring that the lean liquid can flow smoothly into the lean liquid tank, increasing the lean liquid storage space, and ensuring the coordinated operation of the absorption tower and desorption tower under low power load.

[0041] In one embodiment, there are multiple lean liquid tanks 10; and / or multiple rich liquid tanks 20. Figure 1 The document presents three scenarios, namely, a lean liquid tank and a rich liquid tank. When the power system load remains constant, the empty tank remains unchanged. When the power load increases, the rich liquid in the power generation decarbonization unit is replaced by the empty tank and flows into the rich liquid tank, while the lean liquid flows from the lean liquid tank into the low-carbon combustion unit. When the power load decreases, the lean liquid is replaced by the empty tank and flows into the lean liquid tank, while the rich liquid flows from the rich liquid tank into the power generation decarbonization unit. By transferring liquid from the lean or rich liquid zone to the empty tank for replacement, the volume distribution of the storage tank can be flexibly adjusted, simplifying the design.

[0042] In one embodiment, the at least one empty compartment 30 has a vertical, horizontal, or diamond-shaped structure. Different structures of empty compartments can be designed according to actual conditions.

[0043] In one embodiment, at least one empty compartment 30 adopts a multi-level nesting method, and each nested empty compartment can independently adjust its volume.

[0044] When the power load changes, the volume of the lean and rich liquid tanks can be adjusted step by step in layers to achieve more precise regulation and improve the accuracy and stability of volume regulation. For example, during a slow increase in power load, the outer compartment can be used for initial volume adjustment. If this is still insufficient, the inner compartment can be activated for further adjustment.

[0045] In one embodiment, the empty compartment 30 is made of a flexible material.

[0046] The walls of the compartments are made of flexible materials, such as elastic rubber. When adjusting the volume of the lean and rich liquid compartments, the flexible walls can naturally deform according to the liquid pressure, reducing mechanical wear caused by rigid structure adjustments and lowering energy consumption during the adjustment process.

[0047] Figure 5 This is a schematic diagram of the structure of the partition-type lean and rich liquid storage tank in this utility model embodiment, that is, at least one movable partition 40 is used to replace at least one empty chamber.

[0048] The movable partition 40 can adjust the volume distribution between the lean liquid tank 10 and the rich liquid tank 20;

[0049] Each movable partition 40 can move independently;

[0050] Specifically, when the power system load remains constant, the position of the movable partition 40 remains fixed; when the power load increases, the position of at least one movable partition 40 changes so that the volume of the rich liquid tank 20 increases and the volume of the lean liquid tank 10 decreases; when the power load decreases, the position of at least one movable partition 40 changes so that the volume of the lean liquid tank 10 increases and the volume of the rich liquid tank 20 decreases.

[0051] Figure 5 This describes the situation inside the lean and rich liquid storage tank when the power load remains constant. When the power load remains constant, the steam extraction rate of the desorption tower and the production of lean and rich liquids in the baffle-type lean and rich liquid storage tank remain stable, and the position of the movable baffle is fixed, thereby maintaining the smooth operation of the absorption tower and desorption tower and ensuring the stability of the system under non-peak-shaving conditions. Figure 6 This diagram illustrates the changes in lean and rich liquids when the power load increases, as described in this embodiment of the invention. When the power load increases, the steam extraction rate of the desorption tower decreases, leading to a reduction in lean liquid production. At this time, the amount of rich liquid entering the storage tank is greater than the amount of lean liquid. The movable baffle moves in the direction of decreasing lean liquid production, providing more storage space for the rich liquid, ensuring coordinated operation of the absorption tower and desorption tower under high power loads, and meeting the system's peak-shaving requirements. Figure 7 This diagram illustrates the changes in lean and rich liquor when the power load decreases in this embodiment of the invention. When the power load decreases, the steam extraction rate of the desorption tower increases, leading to a corresponding increase in lean liquor production. The amount of lean liquor entering the storage tank is greater than the amount of rich liquor. The movable baffle moves in the direction of increased lean liquor to increase the lean liquor storage space and decrease the rich liquor storage space, ensuring coordinated operation of the absorption tower and desorption tower under low power load and meeting the system's peak-shaving requirements.

[0052] The movable partition 40 can adjust the volume of the lean liquid zone and the rich liquid zone according to the system operation requirements, so as to further optimize the space utilization and operational flexibility of the storage tank.

[0053] In one embodiment, the movable partition 40 is driven by a hydraulic system.

[0054] In one embodiment, the movable partition 40 is a foldable structure.

[0055] When not adjusting the volume, the movable partition can be folded away for storage, reducing space usage; when the volume needs to be adjusted, the movable partition can be unfolded and moved to the appropriate position, improving the flexibility of the movable partition and the space utilization rate.

[0056] In this invention, the lean and rich liquid storage tanks can be designed as multi-layered, three-dimensional structures, with lean and rich liquid tanks distributed on different floors. Liquid transfer between floors is achieved through pipelines and pump sets. This increases the storage capacity of the tanks and provides a more rational spatial layout, adapting to different installation environments.

[0057] A self-cleaning coating or structure can be installed on the inner wall of the lean and rich liquid storage tank. For example, a nano-level superhydrophobic coating can be used to allow impurities and residual liquid adhering to the tank wall to automatically slide off; or a retractable cleaning brush can be installed on the tank wall to clean the tank wall regularly and prevent the accumulation of impurities from affecting the performance of the absorbent.

[0058] In one embodiment, the system further includes a regulating device for controlling the flow of lean and rich liquids between the lean and rich liquids in the lean and rich liquids storage tank 300 and the low-carbon combustion unit 100 and the power generation decarbonization unit 200.

[0059] Specifically, the regulating device mainly includes an absorbent circulation pump to flexibly adjust the liquid storage volume under different operating conditions, in accordance with the load changes of the power generation unit. The integrated lean and rich liquid storage tanks, together with other equipment in the system, meet different peak-shaving requirements.

[0060] In summary, the system proposed in this embodiment effectively solves the problems of large size and low space utilization of traditional dual-tank systems, significantly reducing the tank volume and power plant footprint, thereby lowering facility costs and improving the system's economy and feasibility. This integrated lean and rich liquid storage tank, operating in conjunction with other equipment in the carbon capture and power generation system, achieves flexible peak shaving, providing an efficient peak-shaving operation method and offering a solution with significant economic advantages for the efficient, low-carbon, and flexible operation of coal-fired power plants.

[0061] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above descriptions are merely specific embodiments of this utility model and are not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A lean-rich liquid storage tank characterized by, The system is used in carbon capture and power generation systems and includes: an integrated lean liquid tank (10), a rich liquid tank (20), and at least one empty tank (30) located between the lean liquid tank and the rich liquid tank; The lean liquid tank (10), the rich liquid tank (20), and the empty tank (30) are all equipped with independent inlet and outlet ports; The lean liquid tank (10) is used to store lean liquid; The rich liquid tank (20) is used to store the rich liquid, while the lean liquid and rich liquid are CO2 absorbents in different states. Empty compartment (30), used to adjust the volume distribution of lean and rich liquid compartments; When the power system load remains constant, the volume distribution between the lean liquid tank (10) and the rich liquid tank (20) remains constant; when the power load increases, the rich liquid is replaced by the empty tank (30) and flows into the rich liquid tank (20), while the lean liquid flows out of the lean liquid tank (10); when the power load decreases, the lean liquid is replaced by the empty tank (30) and flows into the lean liquid tank (10), while the rich liquid flows out of the rich liquid tank (20).

2. The lean-rich liquid tank of claim 1, wherein There are multiple lean liquid tanks (10); and / or multiple rich liquid tanks (20).

3. The lean-rich liquid tank of claim 1, wherein The structure of the at least one empty compartment (30) is a vertical structure, a horizontal structure, or a diamond structure.

4. The lean-rich liquid tank of claim 1, wherein At least one empty compartment (30) adopts a multi-level nesting method, and each nested empty compartment can independently adjust its volume.

5. The lean-rich liquid tank of claim 1, wherein The empty compartment (30) is made of flexible material.

6. The lean-rich liquid tank of claim 1, wherein At least one movable partition (40) is used instead of at least one empty compartment; The movable partition (40) can adjust the volume distribution of the lean liquid tank (10) and the rich liquid tank (20); Each movable partition (40) can move independently; When the power system load remains constant, the position of the movable partition (40) remains fixed; when the power load increases, the position of at least one movable partition (40) changes so that the volume of the rich liquid tank (20) increases and the volume of the lean liquid tank (10) decreases; when the power load decreases, the position of at least one movable partition (40) changes so that the volume of the lean liquid tank (10) increases and the volume of the rich liquid tank (20) decreases.

7. The lean-rich liquid tank of claim 6, wherein The movable partition (40) is driven by a hydraulic system.

8. The lean-rich liquid tank of claim 6, wherein The movable partition (40) has a foldable structure.

9. A carbon capture power generation system characterized by, It includes an interconnected low-carbon combustion unit (100), a power generation decarbonization unit (200), and a lean-rich liquid storage tank (300) as described in any one of claims 1 to 5; The low-carbon combustion unit (100) is used to: burn carbon-containing fuels, remove CO2 from flue gas, and generate steam; The power generation decarbonization unit (200) is used to: generate electricity using steam and remove CO2 from the CO2 absorbent; The lean and rich liquid storage tank (300) is used to store CO2 absorbent.

10. The carbon capture power system of claim 9, wherein, It also includes a regulating device for controlling the flow of lean and rich liquids between the lean and rich liquid storage tank (300) and the low-carbon combustion unit (100) and the power generation decarbonization unit (200).

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