Cascade column operation method, device and carbon capture system for large-scale carbon capture process

Abstract

The application provides a cascade two-part tower operation method and device of a large-scale carbon capture process and a carbon capture system, wherein the method comprises the following steps: when the target absorption / desorption capacity demand of the carbon capture system is met, a cascade two-part tower design is adopted to distribute the total absorption / desorption capacity to two towers; according to the total capacity of the absorption / desorption unit, the number of cascade tower groups and the variable load characteristics of the absorption / desorption tower, the corresponding capacity of each absorption / desorption tower is determined; when the total capacity demand cannot be met, a plurality of cascade two-part towers with equal capacity are further adopted to expand the capacity; by matching the capacity of a plurality of absorption / desorption towers with the corresponding load rate, the variable load performance of each tower is optimized to meet the operation demand under the variable load working condition, improve the operation efficiency of the absorption / desorption unit, optimize the operation range and assist the peak shaving operation of the thermal power generating unit; the capacity of each absorption / desorption tower meets the range from the lowest load rate to the full load rate in the operation process.

Description

Technical Field

[0001] This invention relates to the field of carbon capture technology, and more particularly to a cascade tower operation method, apparatus and carbon capture system for a large-scale carbon capture process. Background Technology

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

[0003] Carbon capture and storage (CCS) technology is one of the more mature emission reduction technologies at present, and the commissioning of large-scale capture devices is the key to realizing the large-scale application of this technology.

[0004] Thermal power plants are one of the major sources of carbon dioxide emissions, and full-flow carbon capture technology is considered an effective way to reduce carbon dioxide emissions from thermal power plants. Currently, the annual CO2 emissions of mainstream thermal power units generally exceed 1 million tons, and achieving full-flow carbon capture faces many challenges.

[0005] In full-flow capture systems, the power generation system and the capture unit are highly integrated, and the capacity of individual equipment, especially the absorber / desorber, is extremely large (for example, in the case of full-flow capture of a 1,000 kW unit, the scale of the absorber / desorber will exceed 4 to 8 million tons / year). The following problems may arise in this scenario:

[0006] 1. The processing, manufacturing, installation, operation and maintenance costs of ultra-large equipment are high. If the equipment is designed to have an excessively large capacity but operates under partial load conditions for a long time, it will result in high energy consumption and poor economic efficiency. In the case of large-scale carbon capture (e.g., exceeding 1 million tons / year) and frequent load changes of the unit, it is easy to cause poor equipment operation flexibility, large performance loss under load changes, difficulty in control and maintenance, and high site requirements.

[0007] 2. The variable load range of the power generation system is greater than the load range that the absorption / desorption tower can maintain stable operation, making it difficult for the carbon capture unit to achieve stable operation under all load conditions.

[0008] 3. The load change rate of ultra-large capacity absorption / desorption towers is difficult to match with the load change rate of turbines, which will significantly reduce the response speed of power units and affect system flexibility.

[0009] In summary, there is an urgent need for a technical solution that can overcome the above-mentioned defects, redesign the tower, improve operating conditions, and enhance the system's operational flexibility. Summary of the Invention

[0010] To address the problems existing in the prior art, this invention proposes a tiered tower operation method, apparatus, and carbon capture system for large-scale carbon capture processes. By designing the desorption / absorption towers separately, this invention overcomes the low efficiency, high cost, and poor flexibility of traditional single / multi-tower equal-volume designs under large-scale carbon capture and frequent load variations. It adjusts the design to a multi-tower tiered design for the desorption / absorption towers, optimizing the flexible control of the desorption / absorption tower capacity, broadening the operating range of the absorption / desorption towers, and achieving stepless adjustment of the absorption / desorption tower load.

[0011] In a first aspect of the present invention, a method for operating a cascaded tower in a large-scale carbon capture process is proposed, the method comprising:

[0012] To meet the target absorption / desorption capacity requirements of the carbon capture system, a tiered two-tower design is adopted, in which the total absorption / desorption capacity is distributed to two towers. Specifically, the corresponding capacity of each absorption / desorption tower is determined based on the total capacity of the absorption / desorption unit, the number of tiered tower groups, and the variable load characteristics of the absorption / desorption towers. Each tiered tower group includes two absorption / desorption towers.

[0013] When a single set of cascaded two-stage towers cannot meet the total capacity requirements of the carbon capture system, multiple sets of cascaded two-stage towers of equal capacity are further adopted to meet the overall absorption / desorption load of the carbon capture system in a graded manner, thereby expanding the capacity.

[0014] By matching the capacity and corresponding load rate of multiple absorption / desorption towers, the variable load performance of each tower is optimized to meet the operating requirements under variable load conditions, improve the operating efficiency of the absorption / desorption unit, optimize the operating range of the absorption / desorption unit, and assist the peak-shaving operation of thermal power units; wherein, the capacity of each absorption / desorption tower is sufficient to cover the range from the lowest load rate to the full load rate during the operation of the carbon capture system.

[0015] Furthermore, the method also includes:

[0016] Based on the total flue gas treatment capacity / turbine extraction capacity of the carbon capture system, the total capacity of the absorption / desorption unit is dimensionless, and the dimensionless total capacity is determined to be 1. The absorption / desorption tower is designed as a two-stage tower according to the treatment results.

[0017] Furthermore, based on the total capacity of the absorption / desorption unit, the number of cascade tower groups, and the variable load characteristics of the absorption / desorption towers, the corresponding capacity of each absorption / desorption tower is determined, including:

[0018] The constraint relationship between the dimensionless capacity and the dimensionless total capacity of the tiered tower is as follows:

[0019]

[0020] Where D is the dimensionless total capacity of the absorption / desorption unit; D1 is the dimensionless capacity of the smaller tower in the tiered tower; D2 is the dimensionless capacity of the larger tower in the tiered tower; n represents the number of tiered towers; d s1 d represents the minimum stable operating load rate of the small tower. s2 This represents the minimum stable operating load rate of the large tower; under the aforementioned constraints, the cascade tower satisfies the load requirement from d... s1 Continuous adjustment from D1 to 1.

[0021] Furthermore, the method also includes:

[0022] When setting the dimensionless capacity of the small tower and the dimensionless capacity of the large tower, the goal is to minimize d under the given constraints. s1 Targeting D1, optimize the peak-shaving depth of the tower group.

[0023] Furthermore, in the design of the cascade two-stage absorption / desorption tower, the number of absorption / desorption towers is 2n, where n≥1.

[0024] Furthermore, by matching the capacity and corresponding load rate of multiple absorption / desorption towers, the variable load performance of each tower is optimized to meet the operational requirements under variable load conditions, improve the operating efficiency of the absorption / desorption units, optimize the operating range of the absorption / desorption units, and assist the peak-shaving operation of thermal power units, including:

[0025] When both single-tower and multi-tower operation meet the load demand, single-tower operation shall be given priority.

[0026] When both large and small towers can meet the load demand, the large towers will be prioritized.

[0027] Furthermore, by matching the capacity and corresponding load rate of multiple absorption / desorption towers, the variable load performance of each tower is optimized to meet the operational requirements under variable load conditions, improve the operating efficiency of the absorption / desorption units, optimize the operating range of the absorption / desorption units, and assist the peak-shaving operation of thermal power units, including:

[0028] Configure the optimized operating range for multiple towers, where...

[0029] Load between 0 and d s1 D1, the absorption / desorption unit becomes unstable and shuts down;

[0030] Load at d s1 D1~nd s2 D2, the absorption / desorption unit prioritizes the operation of the smaller towers;

[0031] Load at nd s2 D2~nD2, the absorption / desorption unit prioritizes operation of the large tower;

[0032] The load is between nD2 and 1, and the large and small towers of the absorption / desorption unit operate simultaneously.

[0033] In a second aspect of the present invention, a cascade tower operation device for a large-scale carbon capture process is proposed, the device comprising:

[0034] Absorption / desorption tower;

[0035] The capacity of the absorption / desorption towers is determined using the following method: When meeting the target absorption / desorption capacity requirements of the carbon capture system, a tiered two-tower design is adopted, distributing the total absorption / desorption capacity to two towers. The capacity of each absorption / desorption tower is determined based on the total capacity of the absorption / desorption unit, the number of tiered tower groups, and the variable load characteristics of the absorption / desorption towers. Each tiered tower group includes two absorption / desorption towers. When one tiered two-tower group cannot meet the total capacity requirements of the carbon capture system, multiple tiered two-tower groups of equal capacity are further used to meet the overall absorption / desorption load of the carbon capture system in a tiered manner, thus expanding the capacity.

[0036] The absorption / desorption operation module is used to optimize the variable load performance of each absorption / desorption tower by matching the capacity and corresponding load rate of multiple absorption / desorption towers to meet the operating requirements under variable load conditions, improve the operating efficiency of the absorption / desorption unit, optimize the operating range of the absorption / desorption unit, and assist the peak-shaving operation of thermal power units; wherein, the capacity of each absorption / desorption tower is sufficient to cover the range from the minimum load rate to the full load rate during the operation of the carbon capture system.

[0037] In a third aspect of the present invention, a carbon capture system is proposed, comprising: a cascade tower operation device for a large-scale carbon capture process.

[0038] The tower design and operation method for the absorption / desorption unit of the large-scale carbon capture process proposed in this invention has at least the following technical advantages compared with the prior art:

[0039] 1. Through the multi-tower cascade design of the absorption / desorption tower of the present invention, the capacity of the absorption / desorption tower is optimized and the operating range of the absorption / desorption tower is broadened, and the load of the absorption / desorption tower is infinitely adjustable. The design capacity of a single device can be reduced by the design of large and small towers, and the operation mode of the device can be made more flexible, reducing energy consumption and improving economic efficiency.

[0040] 2. The variable load range of power generation systems is usually between 20% and 120%, while the variable load range of absorption / desorption towers is usually between 60% and 100%. It is difficult to solve the mismatch problem of variable load range by using a single tower and equally divided towers. The absorption / desorption tower capacity design and operation method of the present invention can improve the peak shaving depth, better meet the variable load requirements of power generation systems, and meet the stable operation of a wider range of load conditions.

[0041] 3. The load change rate of a steam turbine is approximately equal to the rate of change of its pumping flow rate, while the load change rate of an absorption / desorption tower is much lower than this rate of change. The load change rate of an absorption / desorption tower should be negatively correlated with its equipment capacity (the larger the single unit capacity, the slower the rate). By designing separate towers, the load change response rate of the overall desorption / absorption unit can be improved, thereby increasing the response speed of the power unit and enhancing system flexibility. Attached Figure Description

[0042] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of the cascade tower operation method of a large-scale carbon capture process according to an embodiment of the present invention.

[0044] Figure 2 This is a schematic diagram of the variable load range according to an embodiment of the present invention.

[0045] Figure 3 This is a schematic diagram showing the relationship between the absorption / desorption capacity and the corresponding load rate of an absorption / desorption tower according to an embodiment of the present invention.

[0046] Figure 4 This is a schematic diagram of the relationship between the tiered tower design according to an embodiment of the present invention.

[0047] Figure 5 This is a schematic diagram of the variable load range of the single-tower design in Example 1.

[0048] Figure 6 This is a schematic diagram of the variable load range of the tower design in Example 1, which adopts an equal division design.

[0049] Figure 7 This is a schematic diagram of the variable load range of the tower design method of the present invention in Example 1.

[0050] Figure 8 This is a schematic diagram of the variable load range of the single-tower design in Example 2.

[0051] Figure 9 This is a schematic diagram of the variable load range of the tower design in Example 2, which adopts an equal division design.

[0052] Figure 10 This is a schematic diagram of the variable load range using the tower design method of the present invention in Example 2. Detailed Implementation

[0053] The principles and spirit of the invention will now be described with reference to several exemplary embodiments. It should be understood that these embodiments are given merely to enable those skilled in the art to better understand and implement the invention, and are not intended to limit the scope of the invention in any way. Rather, these embodiments are provided to make this disclosure more thorough and complete, and to fully convey the scope of this disclosure to those skilled in the art.

[0054] Those skilled in the art will recognize that embodiments of the present invention can be implemented as a system, apparatus, device, method, or computer program product. Therefore, this disclosure can be specifically implemented in the following forms: entirely hardware, entirely software (including firmware, resident software, microcode, etc.), or a combination of hardware and software.

[0055] According to an embodiment of the present invention, a cascade tower operation method, apparatus and carbon capture system for a large-scale carbon capture process are proposed, relating to the field of carbon capture technology.

[0056] The principles and spirit of the present invention will be explained in detail below with reference to several representative embodiments.

[0057] Figure 1 This is a schematic diagram of the cascade tower operation method of a large-scale carbon capture process according to an embodiment of the present invention. Figure 1 As shown, the method includes:

[0058] S101, when meeting the target absorption / desorption capacity requirements of the carbon capture system, a tiered two-tower design is adopted, in which the total absorption / desorption capacity is distributed to two towers through a tiered two-tower approach; wherein, based on the total capacity of the absorption / desorption unit, the number of tiered tower groups, and the variable load characteristics of the absorption / desorption towers, the corresponding capacity of each absorption / desorption tower is determined, and each tiered tower group includes 2 absorption / desorption towers;

[0059] S102, when a set of cascade two-stage towers cannot meet the total capacity requirements of the carbon capture system, multiple sets of cascade two-stage towers of equal capacity are further adopted to meet the overall absorption / desorption load of the carbon capture system in a graded manner, thereby expanding the capacity;

[0060] S103 optimizes the variable load performance of each tower by matching the capacity and corresponding load rate of multiple absorption / desorption towers to meet the operating requirements under variable load conditions, improve the operating efficiency of the absorption / desorption unit, optimize the operating range of the absorption / desorption unit, and assist the peak-shaving operation of thermal power units; wherein, the capacity of each absorption / desorption tower is sufficient to cover the range from the minimum load rate to the full load rate during the operation of the carbon capture system.

[0061] To provide a clearer explanation of the cascade tower operation method of the aforementioned large-scale carbon capture process, each step will be described in detail below.

[0062] In one embodiment, for S101, when meeting the target absorption / desorption capacity requirements of the carbon capture system, a tiered two-tower design is adopted, in which the total absorption / desorption capacity is distributed to two towers through a tiered two-tower approach; wherein, the corresponding capacity of each absorption / desorption tower is determined according to the total capacity of the absorption / desorption unit, the number of tiered tower groups, and the variable load characteristics of the absorption / desorption towers, and each tiered tower group includes 2 absorption / desorption towers.

[0063] Specifically, the method also includes:

[0064] Based on the total flue gas treatment capacity / turbine extraction capacity of the carbon capture system, the total capacity of the absorption / desorption unit is dimensionless, and the dimensionless total capacity is determined to be 1. The absorption / desorption tower is designed as a two-stage tower according to the treatment results.

[0065] Based on the total capacity and variable load characteristics of the absorption / desorption units, a tiered two-tower design for the absorption / desorption towers is implemented; the towers are linked and controlled to meet different operating conditions, covering the range from minimum load rate to full load rate during the operation of the carbon capture system.

[0066] Specifically, based on the dimensionless total capacity of the absorption / desorption unit, the number of cascade tower groups n, and the variable load characteristics of the absorption / desorption towers, the absorption / desorption capacity corresponding to each absorption / desorption tower is determined. Each cascade tower group includes two absorption / desorption towers. The constraint relationship between the dimensionless capacity of the cascade towers and the dimensionless total capacity is as follows:

[0067]

[0068] Where D is the dimensionless total capacity of the absorption / desorption unit; D1 is the dimensionless capacity of the smaller tower in the tiered tower; D2 is the dimensionless capacity of the larger tower in the tiered tower; n represents the number of tiered towers; d s1 d represents the minimum stable operating load rate of the small tower. s2 This represents the minimum stable operating load rate of the large tower; under the aforementioned constraints, the cascade tower satisfies the load requirement from d... s1 Continuous adjustment from D1 to 1.

[0069] In one embodiment, when setting the dimensionless capacity of the small tower and the dimensionless capacity of the large tower, the constraint relationship is to minimize d. s1 Targeting D1, optimize the peak-shaving depth of the tower group.

[0070] refer to Figure 2 This is a schematic diagram of the variable load range according to an embodiment of the present invention. Figure 3 This is a schematic diagram showing the relationship between the absorption / desorption capacity and the corresponding load rate of an absorption / desorption tower according to an embodiment of the present invention. Figure 2 and Figure 3 As shown, this is illustrated using a single-tiered bisection tower (n=1):

[0071] 0 to d s1 ×D1 represents the absorption / desorption shutdown range, d s1 ×D1 to D1+D2 can all be covered by small towers operating alone, large towers operating alone, or both towers operating simultaneously.

[0072] Specifically, load 0~d s1 D1 absorption / desorption unit malfunctioned and shut down;

[0073] Load d s1 D1~D1 is the separate operating range for the small tower;

[0074] Load d s2 D2~D2 is the separate operating zone for the large tower;

[0075] Load D2~1 refers to the simultaneous operation of the large tower and the small tower.

[0076] Among them, Figure 2 In the middle, there are two sections where the load is simultaneously covered. In these two sections, the larger tower takes priority in operation. That is, for load d... s2 D2~D2, the absorption / desorption unit prioritizes the operation of the large tower.

[0077] For overall load factor The various load rates between 1 and 1 are achieved through a split-tower design, while, If it is as small as possible, it can ensure that the variable load range of the absorption / desorption unit is as large as possible.

[0078] In one embodiment, for S102, when a set of cascaded two-stage towers cannot meet the total capacity requirement of the carbon capture system, multiple sets of cascaded two-stage towers of equal capacity are further adopted to meet the overall absorption / desorption load of the carbon capture system in a graded manner, thereby expanding the capacity.

[0079] In one embodiment, in the cascade two-stage tower design, the number of absorption / desorption towers is 2n, where n≥1.

[0080] For details, please refer to Figure 4 This is a schematic diagram illustrating the relationship between the tiered tower design according to an embodiment of the present invention. In practical scenarios, multiple sets of equal-capacity tiered bi-tiered towers can be used according to capacity requirements.

[0081] In one embodiment, for S103, by matching the capacity of multiple absorption / desorption towers with their corresponding load rates, the variable load performance of each tower is optimized to meet the operating requirements under variable load conditions, improve the operating efficiency of the absorption / desorption unit, optimize the operating range of the absorption / desorption unit, and assist the thermal power unit in peak shaving operation; wherein, the capacity of each absorption / desorption tower is sufficient to cover the range from the lowest load rate to the full load rate during the operation of the carbon capture system.

[0082] Specifically, when both single-tower and multi-tower operation meet the load demand, single-tower operation will be given priority.

[0083] When both large and small towers can meet the load demand, the large towers will be prioritized.

[0084] Specifically, for n sets of tiered bi-splitting towers, optimize the operating range for each tower, where...

[0085] Load between 0 and d s1 D1, the absorption / desorption unit becomes unstable and shuts down;

[0086] Load at d s1 D1~nd s2 D2, the absorption / desorption unit prioritizes the operation of the smaller towers;

[0087] Load at nd s2 D2~nD2, the absorption / desorption unit prioritizes operation of the large tower;

[0088] The load is between nD2 and 1, and the large and small towers of the absorption / desorption unit operate simultaneously.

[0089] In practical applications, both absorption towers and desorption towers can be designed as separate towers, and the specific principles are similar to those of separate tower design methods.

[0090] It should be noted that although the operation of the method of the present invention has been described in a specific order in the above embodiments and figures, this does not require or imply that the operations must be performed in that specific order, or that all the operations shown must be performed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0091] The present invention will now be described with reference to specific embodiments.

[0092] Example 1:

[0093] For the absorption / desorption unit, based on the total flue gas treatment capacity / turbine extraction capacity, the absorption / desorption capacity D of the absorption / desorption unit is dimensionlessly reduced to 1, and the minimum stable operating load rate d of the large and small towers is determined. s1 =d s2 =0.6. If a single-tower design or an equally distributed design is adopted, the variable load range can be referenced. Figure 5 and Figure 6 As shown.

[0094] like Figure 5 As shown, in single-tower design, the variable load range for single-tower operation is 60% to 100%; 0% to 60% is the range for instability and shutdown.

[0095] like Figure 6 As shown, when using a split-tower design, the absorption / desorption capacity D1 of the first absorption / desorption tower is 50%, and the absorption / desorption capacity D2 of the second absorption / desorption tower is 50%. Since the absorption / desorption capacities of the two towers are the same, the variable load range for single-tower operation is 30% to 50%, and the variable load range for dual-tower operation is 60% to 100%. 0% to 30% and 50% to 60% are the instability shutdown ranges.

[0096] In this embodiment, the carbon capture system operation method based on the absorption / desorption unit-based tower design proposed in this invention is adopted. The absorption / desorption capacity D1 of the first absorption / desorption tower is 37.5%, and the absorption / desorption capacity D2 of the second absorption / desorption tower is 62.5%. (Reference) Figure 7 The variable load range for small towers operating alone is 22.5% to 37.5%, the variable load range for large towers operating alone is 37.5% to 62.5%, and the variable load range for both towers operating simultaneously is 60% to 100%; 0% to 22.5% is the range for instability and shutdown.

[0097] Compared to Figure 5 and Figure 6 The single-tower and equally divided designs mentioned above are addressed by the multi-tower design proposed in this invention, which utilizes a stepped design. Figure 7 The peak shaving depth of the absorption / desorption unit was increased by 37.5% and 7.5% respectively, achieving stepless adjustment from 22.5% to 100% load.

[0098] Example 2:

[0099] For the absorption / desorption unit, based on the total flue gas treatment capacity / turbine extraction capacity, the absorption / desorption capacity D of the absorption / desorption unit is dimensionlessly reduced to 1, and the minimum stable operating load rate d of the large and small towers is determined. s1 =d s2 =0.5. If a single-tower design or an equally distributed design is adopted, the variable load range can be referenced. Figure 8 and Figure 9As shown.

[0100] like Figure 8 As shown, in single-tower design, the variable load range for single-tower operation is 50% to 100%; 0% to 50% is the range for instability and shutdown.

[0101] like Figure 9 As shown, when using a split-tower design, the absorption / desorption capacity D1 of the first absorption / desorption tower is 50%, and the absorption / desorption capacity D2 of the second absorption / desorption tower is 50%. Since the absorption / desorption capacities of the two towers are the same, the variable load range for single-tower operation is 25% to 50%, and the variable load range for dual-tower operation is 25% to 100%. There is no instability zone within the range of 25% to 100%.

[0102] In this embodiment, the carbon capture system operation method based on the absorption / desorption unit-based tower design proposed in this invention is adopted. The absorption / desorption capacity D1 of the first absorption / desorption tower is 33.3%, and the absorption / desorption capacity D2 of the second absorption / desorption tower is 66.6%. (Reference) Figure 10 The variable load range for small towers operating alone is 16.6% to 33.3%, the variable load range for large towers operating alone is 33.3% to 66.6%, and the variable load range for both towers operating simultaneously is 16.6% to 100%; 0% to 16.6% is the range for instability and shutdown.

[0103] Compared to Figure 8 and Figure 9 The single-tower and equally divided designs mentioned above are addressed by the multi-tower design proposed in this invention, which utilizes a stepped design. Figure 10 This invention can only improve the peak tuning depth, increasing the peak tuning depth of the absorption / desorption units by 33.4% and 8.4% respectively. s It is more efficient under conditions greater than 0.5.

[0104] Where, d s The minimum stable (or optimized) operating load rate for the absorption / desorption tower.

[0105] During peak-shaving operation, the operation methods of the absorption / desorption units in the tower design should at least include:

[0106] By matching the capacity and corresponding load rate of multiple absorption / desorption towers, the variable load performance of each tower is optimized to meet the operating requirements under variable load conditions, improve the operating efficiency of the absorption / desorption unit, optimize the operating range of the absorption / desorption unit, and assist the peak-shaving operation of thermal power units.

[0107] 1. When both single-tower and multi-tower operation meet the load requirements, single-tower operation should be prioritized to reduce the difficulty of operation and control and improve system reliability.

[0108] In practical applications, the capacity design of the tower should focus on the variable load requirements of the generator set, so that the high-frequency operating load of the unit is covered by the optimal operating load area of ​​the tower.

[0109] 2. When both large and small towers can meet the load requirements, the large tower should be prioritized.

[0110] In fact, the two towers have their own optimal operating ranges. The smaller tower has a faster response speed, while the larger tower has lower energy consumption and better economic efficiency. For operating conditions with low peak shaving depth and relatively stable operation, the larger tower should be selected first.

[0111] 3. When the carbon capture system operates at peak load (increase load), the small tower is switched to a large tower or the large tower is switched to a dual tower; when the carbon capture system operates at peak load (decrease load), the large tower is switched to a small tower or the dual tower is switched to a large tower.

[0112] In one embodiment, based on the same inventive concept, the present invention also proposes a cascade tower operation device for a large-scale carbon capture process, the device comprising:

[0113] Absorption / desorption tower;

[0114] The capacity of the absorption / desorption towers is determined using the following method: When meeting the target absorption / desorption capacity requirements of the carbon capture system, a tiered two-tower design is adopted, distributing the total absorption / desorption capacity to two towers. The capacity of each absorption / desorption tower is determined based on the total capacity of the absorption / desorption unit, the number of tiered tower groups, and the variable load characteristics of the absorption / desorption towers. Each tiered tower group includes two absorption / desorption towers. When one tiered two-tower group cannot meet the total capacity requirements of the carbon capture system, multiple tiered two-tower groups of equal capacity are further used to meet the overall absorption / desorption load of the carbon capture system in a tiered manner, thus expanding the capacity.

[0115] The absorption / desorption operation module is used to optimize the variable load performance of each absorption / desorption tower by matching the capacity and corresponding load rate of multiple absorption / desorption towers to meet the operating requirements under variable load conditions, improve the operating efficiency of the absorption / desorption unit, optimize the operating range of the absorption / desorption unit, and assist the peak-shaving operation of thermal power units; wherein, the capacity of each absorption / desorption tower is sufficient to cover the range from the minimum load rate to the full load rate during the operation of the carbon capture system.

[0116] In another embodiment, based on the same inventive concept, the present invention also proposes a carbon capture system, which includes a cascade tower operation device for a large-scale carbon capture process.

[0117] This invention uses the total flue gas treatment capacity / turbine extraction capacity of the carbon capture system to make the total capacity of the absorption / desorption units dimensionless. Based on the dimensionless total capacity of the absorption / desorption units, the number of cascade towers (two towers per group), and the variable load characteristics of the absorption / desorption towers, the absorption / desorption capacity of each absorption / desorption tower is determined. The absorption / desorption units are designed to cover all load rates from the lowest load rate to 1 during the operation of the carbon capture system.

[0118] During the operation of the carbon capture system, by matching the capacity of multiple absorption / desorption units with their corresponding load rates, the system expands the stable operating load range of the carbon capture units under variable load conditions, optimizes the variable load performance of the absorption / desorption units, and assists in peak-shaving operation of thermal power units. This includes: prioritizing single-tower operation when both single-tower and multi-tower operation meet load requirements; and prioritizing large-tower operation when both large-tower and small-tower operation meet load requirements.

[0119] The tower design and operation method for the absorption / desorption unit of the large-scale carbon capture process proposed in this invention has at least the following technical advantages compared with the prior art:

[0120] 1. Through the multi-tower cascade design of the absorption / desorption tower of the present invention, the capacity of the absorption / desorption tower is optimized and the operating range of the absorption / desorption tower is broadened, and the load of the absorption / desorption tower is infinitely adjustable. The design capacity of a single device can be reduced by the design of large and small towers, and the operation mode of the device can be made more flexible, reducing energy consumption and improving economic efficiency.

[0121] 2. The variable load range of power generation systems is usually between 20% and 120%, while the variable load range of absorption / desorption towers is usually between 60% and 100%. It is difficult to solve the mismatch problem of variable load range by using a single tower and equally divided towers. The absorption / desorption tower capacity design and operation method of the present invention can improve the peak shaving depth, better meet the variable load requirements of power generation systems, and meet the stable operation of a wider range of load conditions.

[0122] 3. The load change rate of a steam turbine is approximately equal to the rate of change of its pumping flow rate, while the load change rate of an absorption / desorption tower is much lower than this rate of change. The load change rate of an absorption / desorption tower should be negatively correlated with its equipment capacity (the larger the single unit capacity, the slower the rate). By designing separate towers, the load change response rate of the overall desorption / absorption unit can be improved, thereby increasing the response speed of the power unit and enhancing system flexibility.

[0123] The acquisition, storage, use, and processing of data in this application all comply with relevant laws and regulations.

[0124] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, apparatus, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0125] This invention is described with reference to flowchart illustrations and / or block diagrams of methods and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0126] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0127] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0128] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for operating a cascaded tower system in a large-scale carbon capture process, characterized in that, The method includes: To meet the target absorption / desorption capacity requirements of the carbon capture system, a tiered two-tower design is adopted, in which the total absorption / desorption capacity is distributed to two towers. Specifically, the corresponding capacity of each absorption / desorption tower is determined based on the total capacity of the absorption / desorption unit, the number of tiered tower groups, and the variable load characteristics of the absorption / desorption towers. Each tiered tower group includes two absorption / desorption towers. When a single set of cascaded two-stage towers cannot meet the total capacity requirements of the carbon capture system, multiple sets of cascaded two-stage towers of equal capacity are further adopted to meet the overall absorption / desorption load of the carbon capture system in a graded manner, thereby expanding the capacity. By matching the capacity and corresponding load rate of multiple absorption / desorption towers, the variable load performance of each tower is optimized to meet the operating requirements under variable load conditions, improve the operating efficiency of the absorption / desorption unit, optimize the operating range of the absorption / desorption unit, and assist the peak-shaving operation of thermal power units; wherein, the capacity of each absorption / desorption tower is sufficient to cover the range from the lowest load rate to the full load rate during the operation of the carbon capture system. The method also includes: Based on the total flue gas treatment capacity / turbine extraction capacity of the carbon capture system, the total capacity of the absorption / desorption unit is dimensionless, and the dimensionless total capacity is determined to be 1. The absorption / desorption tower is designed as a two-stage tower according to the treatment results. To meet the target absorption / desorption capacity requirements of the carbon capture system, a tiered two-tower design is adopted, distributing the total absorption / desorption capacity to two towers. The capacity of each absorption / desorption tower is determined based on the total capacity of the absorption / desorption units, the number of tiered tower groups, and the variable load characteristics of the absorption / desorption towers. Each tiered tower group includes two absorption / desorption towers, including: The constraint relationship between the dimensionless capacity and the dimensionless total capacity of the tiered tower is as follows: in, The dimensionless total capacity of the absorption / desorption unit; The dimensionless capacity of the smaller towers in the tiered tower; The dimensionless capacity of the largest tower in a tiered tower; Indicates the number of tiered towers; This represents the minimum stable operating load rate for the small tower. This represents the minimum stable operating load rate of the main tower; under the aforementioned constraints, the cascade tower satisfies the load distribution from... Continuous adjustment up to 1; When setting the dimensionless capacity of the small tower and the dimensionless capacity of the large tower, minimize the following under the constraints. To achieve this goal, optimize the peak-shaving depth of the tower group.

2. The cascade tower operation method for the large-scale carbon capture process according to claim 1, characterized in that, In the design of a tiered two-stage absorption / desorption tower, the number of absorption / desorption towers is 2. , ≥1.

3. The cascade tower operation method for the large-scale carbon capture process according to claim 1, characterized in that, By matching the capacity and corresponding load rate of multiple absorption / desorption towers, the variable load performance of each tower is optimized to meet the operational requirements under variable load conditions, improve the operating efficiency of the absorption / desorption units, optimize the operating range of the absorption / desorption units, and assist in peak-shaving operation of thermal power units, including: When both single-tower and multi-tower operation meet the load demand, single-tower operation shall be given priority. When both large and small towers can meet the load demand, the large towers will be prioritized.

4. The cascade tower operation method for the large-scale carbon capture process according to claim 1, characterized in that, By matching the capacity and corresponding load rate of multiple absorption / desorption towers, the variable load performance of each tower is optimized to meet the operational requirements under variable load conditions, improve the operating efficiency of the absorption / desorption units, optimize the operating range of the absorption / desorption units, and assist in peak-shaving operation of thermal power units, including: Configure the optimized operating range for multiple towers, where... Load at 0~ The absorption / desorption unit becomes unstable and shuts down; Load at ~ The absorption / desorption unit prioritizes the operation of the smaller towers; Load at ~ The absorption / desorption unit prioritizes operation of the large tower; Load at ~1, The large and small towers of the absorption / desorption unit operate simultaneously.

5. A cascade tower operation device for a large-scale carbon capture process, comprising a cascade tower operation method for implementing the large-scale carbon capture process according to any one of claims 1 to 4, characterized in that, The device includes: Absorption / desorption tower; The capacity of the absorption / desorption towers is determined using the following method: When meeting the target absorption / desorption capacity requirements of the carbon capture system, a tiered two-tower design is adopted, distributing the total absorption / desorption capacity to two towers. The capacity of each absorption / desorption tower is determined based on the total capacity of the absorption / desorption unit, the number of tiered tower groups, and the variable load characteristics of the absorption / desorption towers. Each tiered tower group includes two absorption / desorption towers. When one tiered two-tower group cannot meet the total capacity requirements of the carbon capture system, multiple tiered two-tower groups of equal capacity are further used to meet the overall absorption / desorption load of the carbon capture system in a tiered manner, thus expanding the capacity. The absorption / desorption operation module is used to optimize the variable load performance of each absorption / desorption tower by matching the capacity and corresponding load rate of multiple absorption / desorption towers to meet the operating requirements under variable load conditions, improve the operating efficiency of the absorption / desorption unit, optimize the operating range of the absorption / desorption unit, and assist the peak-shaving operation of thermal power units; wherein, the capacity of each absorption / desorption tower is sufficient to cover the range from the minimum load rate to the full load rate during the operation of the carbon capture system.

6. A carbon capture system, characterized in that, The carbon capture system includes: a cascade tower operation device for the large-scale carbon capture process as described in claim 5.

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