Carbon dioxide capture and caustic evaluation system and method of evaluation thereof

Abstract

The application relates to a carbon dioxide capture and alkali production evaluation system and an evaluation method thereof, and belongs to the technical field of carbon dioxide capture and alkali production. The carbon dioxide capture and alkali production evaluation system comprises the following: a monitoring unit that monitors a first carbon dioxide concentration C1, a first ammonia concentration N1, a second carbon dioxide concentration C2 and a second ammonia concentration N2 and sends the concentrations to a central processing unit; a monitoring unit that monitors the purity NP1 and impurity content NP2 of a sodium carbonate product and the purity LP1 and impurity content LP2 of an ammonium chloride product and sends the concentrations to the central processing unit; and the central processing unit evaluates the carbon dioxide capture capacity according to the first carbon dioxide concentration C1, the first ammonia concentration N1, the second carbon dioxide concentration C2 and the second ammonia concentration N2, and evaluates the alkali production quality according to the purity NP1 and impurity content NP2 of the sodium carbonate product and the purity LP1 and impurity content LP2 of the ammonium chloride product. The application can evaluate the high-efficiency carbon dioxide capture capacity, the quality of the sodium carbonate and ammonium chloride products, and achieve the balance between economic benefits and environmental benefits.

Description

Technical Field

[0001] The present invention belongs to the technical field of carbon dioxide capture and alkali production, and in particular relates to a carbon dioxide capture and alkali production evaluation system and an evaluation method thereof. Background Art

[0002] CO2 capture technology is widely regarded as one of the key technologies for addressing climate change and reducing CO2 concentrations in the atmosphere. As a dual-function industrial process, CO2 capture and alkali production can not only help mitigate greenhouse gas emissions but also realize the resource utilization of carbon dioxide. However, despite some progress in CO2 capture technology, how to improve the capture efficiency and the quality of by-products such as sodium carbonate (Na2CO3) and ammonium chloride (NH4Cl) in actual operation remains an urgent problem to be solved. Especially in the alkali production process, accurate gas analysis and data acquisition are not only related to the CO2 capture efficiency, but also directly affect the purity and final quality of by-products such as sodium carbonate (Na2CO3) and ammonium chloride (NH4Cl). Therefore, mastering and real-time monitoring of these key process parameters has become a key factor in improving overall production efficiency and product quality.

[0003] However, most existing technologies focus on the optimization and control of a single parameter or local process, such as CO2 concentration monitoring or by-product purity analysis, and often lack a comprehensive evaluation of the entire CO2 capture and alkali production process. For example, they only focus on the CO2 capture efficiency, or only emphasize product quality. Therefore, when dealing with complex industrial processes, existing technologies have failed to provide a multi-dimensional, unified and comprehensive solution. It has become an urgent task to develop an integrated CO2 capture and alkali production process evaluation system that can comprehensively and real-time monitor key parameters, optimize the collaborative work of various links, and improve overall process efficiency. Summary of the Invention

[0004] This invention proposes a carbon dioxide capture and alkali production evaluation system and method, aiming to partially or completely address the existing technical issues of achieving comprehensive quality assessment of carbon dioxide capture and alkali production from industrial waste gas. The technical solution of this invention is as follows:

[0005] In a first aspect, a carbon dioxide capture alkali production evaluation system comprises:

[0006] A first carbon dioxide concentration monitoring unit monitors the first carbon dioxide concentration C1 of carbon dioxide in the industrial waste gas entering the first reaction tower and sends it to the central processing unit; a first ammonia concentration monitoring unit monitors the first ammonia concentration N1 of ammonia in the industrial waste gas entering the first reaction tower and sends it to the central processing unit;

[0007] The first reaction tower captures carbon dioxide and ammonia in industrial waste gas and reacts them to produce ammonium carbonate;

[0008] A second carbon dioxide concentration monitoring unit monitors the second carbon dioxide concentration C2 in the first reaction tower after the capture reaction is completed and sends it to the central processing unit; a second ammonia concentration monitoring unit monitors the second ammonia concentration N2 in the first reaction tower after the capture reaction is completed and sends it to the central processing unit;

[0009] In the second reaction tower, ammonium carbonate reacts with sodium chloride solution to produce sodium bicarbonate and ammonium chloride, the sodium bicarbonate and ammonium chloride are separated, and the ammonium chloride is cooled and crystallized to produce the ammonium chloride product; in the third reaction tower, the sodium bicarbonate is heated to produce the sodium carbonate product;

[0010] The sodium carbonate product purity monitoring unit monitors the purity NP1 and impurity content NP2 of the sodium carbonate product and sends the results to the central processing unit; the ammonium chloride product purity monitoring unit monitors the purity LP1 and impurity content LP2 of the ammonium chloride product and sends the results to the central processing unit;

[0011] The central processing unit evaluates the carbon dioxide capture capacity based on the first carbon dioxide concentration C1, the first ammonia concentration N1, the second carbon dioxide concentration C2, and the second ammonia concentration N2; and evaluates the alkali production quality based on the purity NP1 and impurity content NP2 of the sodium carbonate product and the purity LP1 and impurity content LP2 of the ammonium chloride product.

[0012] Optionally, the carbon dioxide capture capacity includes: a first capture index and a second capture index, the first capture index CC=|C1-C2| / C1, and the second capture index CN=|N1-N2| / N1.

[0013] Optionally, the alkali production quality includes: a first quality index and a second quality index, the first quality index QC = |NP1-NP2| / NP1, and the second quality index QL = |LP1-LP2| / LP1.

[0014] Optionally, when CC≥99% and CN≥98%, the carbon dioxide capture capacity is evaluated to be qualified, and when QC≥99% and QL≥96%, the alkali production quality is evaluated to be qualified.

[0015] In a second aspect, a method for evaluating carbon dioxide capture and alkali production includes:

[0016] Step S100: monitoring a first carbon dioxide concentration C1 of carbon dioxide in the industrial waste gas entering the first reaction tower and sending the result to the central processing unit; monitoring a first ammonia concentration N1 of ammonia in the industrial waste gas entering the first reaction tower and sending the result to the central processing unit;

[0017] Step S200: A first reaction tower captures carbon dioxide and ammonia in the industrial waste gas and reacts them to generate ammonium carbonate; a second carbon dioxide concentration C2 in the first reaction tower is monitored after the capture reaction is completed and sent to the central processing unit; a second ammonia concentration N2 in the first reaction tower is monitored after the capture reaction is completed and sent to the central processing unit;

[0018] Step S300: reacting ammonium carbonate with a sodium chloride solution to generate sodium bicarbonate and ammonium chloride, separating the sodium bicarbonate and ammonium chloride, heating the sodium bicarbonate to generate a sodium carbonate product, and cooling and crystallizing the ammonium chloride to generate an ammonium chloride product;

[0019] Step S400: monitor the purity NP1 and impurity content NP2 of the sodium carbonate product and send them to the central processing unit; monitor the purity LP1 and impurity content LP2 of the ammonium chloride product and send them to the central processing unit;

[0020] Step S500: The central processing unit evaluates the carbon dioxide capture capacity based on the first carbon dioxide concentration C1, the first ammonia concentration N1, the second carbon dioxide concentration C2, and the second ammonia concentration N2; and evaluates the alkali production quality based on the purity NP1 and impurity content NP2 of the sodium carbonate product and the purity LP1 and impurity content LP1 of the ammonium chloride product.

[0021] Optionally, in step S500, the carbon dioxide capture capability includes: a first capture index and a second capture index, the first capture index CC=|C1-C2| / C1, and the second capture index CN=|N1-N2| / N1.

[0022] Optionally, in step S500, the alkali production quality includes: a first quality index and a second quality index, the first quality index QC = |NP1-NP2| / NP1, and the second quality index QL = |LP1-LP2| / LP1.

[0023] Optionally, in step S500, when CC≥99% and CN≥98%, the carbon dioxide capture capacity is evaluated to be qualified; and when QC≥99% and QL≥96%, the alkali production quality is evaluated to be qualified.

[0024] The beneficial effects achieved by the present invention are as follows:

[0025] (1) In the present application, the central processing unit is capable of monitoring the first carbon dioxide concentration, the first ammonia concentration, the second carbon dioxide concentration, and the second ammonia concentration to analyze and evaluate the carbon dioxide capture capacity; at the same time, the central processing unit is also capable of evaluating the quality of alkali production based on the purity and impurity content of the sodium carbonate product and the purity and impurity content of the ammonium chloride product, and then adjusting the carbon dioxide capture alkali production process parameters (such as reaction temperature, pressure, gas flow rate, gas flow rate, etc.) to adjust the carbon dioxide capture capacity. Through this integrated carbon dioxide capture alkali production evaluation system, the carbon dioxide capture capacity and the quality of the sodium carbonate and ammonium chloride products can be evaluated, the energy utilization efficiency in the carbon dioxide capture and alkali production process can be improved, the operating costs can be reduced, the environmental pollution can be reduced, and a balance between economic and environmental benefits can be achieved.

[0026] (2) In the present application, by setting the first capture index CC, the second capture index CN, the first quality index QC and the second quality index QL, the first capture index CC and the second capture index CN provide quantitative evaluation standards for the carbon dioxide capture capacity, which can reflect the capture efficiency of carbon dioxide and ammonia and the optimization requirements of reaction conditions; the first quality index QC and the second quality index QL provide quality control standards for the sodium carbonate output and the ammonium chloride purity in the alkali production process, respectively, to ensure the high quality and high purity of the final product, meet the needs of the market and industry, and bring higher economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 A schematic diagram of the composition of a carbon dioxide capture and alkali production evaluation system applied for by the present invention;

[0029] Figure 2 A schematic diagram of a carbon dioxide capture and alkali production evaluation method applied for by the present invention;

[0030] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments; based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0032] In the description of the present invention, it should be understood that the terms "upper," "lower," "front," "back," "left," "right," "top," "bottom," "inside," "outside," and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended only to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the units or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. To make the objectives, technical solutions, and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0033] First, as Figure 1 As shown, a carbon dioxide capture alkali production evaluation system S includes:

[0034] like Figure 1 As shown, a carbon dioxide capture alkali production evaluation system S includes:

[0035] The first carbon dioxide concentration monitoring unit 101 monitors the first carbon dioxide concentration C1 of carbon dioxide in the industrial waste gas entering the first reaction tower and sends it to the central processing unit 400;

[0036] The first ammonia concentration monitoring unit 102 monitors the first ammonia concentration N1 of the ammonia in the industrial waste gas entering the first reaction tower and sends it to the central processing unit 400;

[0037] The first reaction tower captures carbon dioxide and ammonia in industrial waste gas and reacts them to produce ammonium carbonate;

[0038] The second carbon dioxide concentration monitoring unit 201 monitors the second carbon dioxide concentration C2 in the first reaction tower after the capture reaction is completed and sends it to the central processing unit 400;

[0039] The second ammonia concentration monitoring unit 202 monitors the second ammonia concentration N2 in the first reaction tower after the capture reaction is completed and sends it to the central processing unit;

[0040] In the second reaction tower, ammonium carbonate reacts with sodium chloride solution to produce sodium bicarbonate and ammonium chloride, the sodium bicarbonate and ammonium chloride are separated, and the ammonium chloride is cooled and crystallized to produce an ammonium chloride product;

[0041] The third reaction tower heats the sodium bicarbonate to generate a sodium carbonate product.

[0042] Sodium carbonate product purity monitoring unit 301 monitors the purity NP1 and impurity content NP2 of the sodium carbonate product and sends them to the central processing unit 400;

[0043] The ammonium chloride product purity monitoring unit 302 monitors the purity LP1 and impurity content LP2 of the ammonium chloride product and sends them to the central processing unit 400;

[0044] The central processing unit 400 evaluates the carbon dioxide capture capacity based on the first carbon dioxide concentration C1, the first ammonia concentration N1, the second carbon dioxide concentration C2, and the second ammonia concentration N2; and evaluates the alkali production quality based on the purity NP1 and impurity content NP2 of the sodium carbonate product and the purity LP1 and impurity content LP2 of the ammonium chloride product.

[0045] In some embodiments, the first carbon dioxide concentration monitoring unit 101 can be installed at the entrance of the first reaction tower to monitor the first carbon dioxide concentration in the industrial waste gas, and a high-precision infrared analysis technology (such as non-dispersive infrared absorption method) can be used to detect the first carbon dioxide concentration entering the first reaction tower. In this way, the first carbon dioxide concentration monitoring unit 101 can monitor the concentration change of the first carbon dioxide in real time. Before the waste gas enters the capture reaction, the first carbon dioxide concentration monitoring unit measures the initial concentration of carbon dioxide to provide baseline data for subsequent reactions. The first carbon dioxide concentration monitoring unit must have high sensitivity and wide-range measurement capabilities to cope with fluctuations in the carbon dioxide concentration in industrial waste gas and ensure the accuracy and timeliness of the data.

[0046] In some embodiments, the first ammonia concentration monitoring unit 102 can be installed at the entrance of the first reaction tower to monitor the concentration of ammonia entering the first reaction tower in real time. The first ammonia concentration monitoring unit 102 can generally use an electrochemical sensor or an infrared absorption sensor, which has high detection accuracy to ensure that changes in ammonia concentration can be captured in real time.

[0047] In some embodiments, the first reaction tower includes an air inlet, a discharge port and a spray device, carbon dioxide and ammonia in the industrial waste gas enter the first reaction tower through the air inlet, the spray device sprays water mist, and the discharge port collects ammonium carbonate. In the first reaction tower, carbon dioxide in the industrial waste gas reacts with ammonia at a controlled temperature (e.g., 50-80°C) and pressure (e.g., 1-2MPa) to generate ammonium carbonate (NH4)2CO3. In order to ensure the high efficiency of the reaction, the first reaction tower is equipped with a flow control, temperature regulation, stirring and gas guiding system to ensure that the gas is evenly distributed and the reaction is complete. The flow rate, temperature and pressure of the carbon dioxide and ammonia gases in the first reaction tower are adjusted by an external control system to improve the capture effect of carbon dioxide, so as to achieve sufficient mixing of the carbon dioxide and ammonia reaction gases and complete conversion of the reactants.

[0048] In some embodiments, a second carbon dioxide concentration monitoring unit 201 is installed at the outlet of the first reaction tower to monitor the carbon dioxide concentration after the reaction in order to evaluate the thoroughness of the reaction; similarly, the second carbon dioxide concentration monitoring unit needs to have high measurement accuracy and be able to cope with fluctuations in gas concentration during the reaction to ensure the accuracy of the monitoring results.

[0049] In some embodiments, a second ammonia concentration monitoring unit 202 is installed at the outlet of the first reaction tower to monitor the ammonia concentration in real time. The residual ammonia concentration affects the ammonium carbonate production rate and reaction stability. Therefore, the second ammonia concentration monitoring unit also needs to have good response time and sensitivity.

[0050] In some embodiments, the second reaction tower is used to react the generated ammonium carbonate with a sodium chloride solution to generate sodium bicarbonate (NaHCO3) and ammonium chloride (NH4Cl). The second reaction tower includes a tower body, which is provided with an ammonium carbonate inlet and a sodium chloride inlet. An agitator is provided inside the tower body to fully mix and react the ammonium carbonate and sodium chloride materials. A discharge port is provided at the bottom of the tower body. The temperature, pressure, and solution concentration within the second reaction tower can be controlled by at least an external control system to ensure the high efficiency of the reaction. At the same time, the second reaction tower also includes a separation unit, and the discharge port is connected to the separation unit to ensure that the generated ammonium chloride and sodium bicarbonate can be separated. The ammonium chloride can be purified by a conventional cooling crystallization unit in the prior art to obtain an ammonium chloride product. The second reaction tower can not only support the chemical reaction of the ammonium carbonate and the sodium chloride solution, but also support the separation and recovery of the solution.

[0051] In some embodiments, the third reaction tower includes a feed port, a heating device, and a discharge port. The feed port is used to feed sodium bicarbonate, and the heating device heats and calcines the sodium bicarbonate to generate sodium carbonate (Na2CO3), which is collected from the discharge port. In this process, the reaction temperature, pressure, and gas flow rate need to be precisely controlled to achieve high yield and high purity of sodium carbonate. The CO2 gas released during the calcination process can be captured and refluxed to the first reaction tower for reuse. The heating system in the third reaction tower needs to have efficient heat exchange performance to reduce energy consumption while ensuring the completeness and efficiency of the sodium bicarbonate heating and calcination reaction.

[0052] In some embodiments, the sodium carbonate product purity monitoring unit 301 is used to monitor the purity and impurity content of the generated sodium carbonate product. Typically, high-precision equipment such as a spectrometer or X-ray diffractometer is used to analyze the purity and impurity content of the generated sodium carbonate product. This can accurately measure the purity of the sodium carbonate and ensure that the purity of the sodium carbonate meets industrial standards.

[0053] In some embodiments, the ammonium chloride product purity monitoring unit 302 is used to monitor the purity and impurity content of ammonium chloride in real time. The purity of ammonium chloride is crucial for its use as an industrial raw material. This unit uses gas chromatography or liquid chromatography technology to analyze the impurities in ammonium chloride in real time and adjust production parameters to ensure the purity of ammonium chloride.

[0054] In the carbon dioxide capture and alkali production evaluation system of the present invention, the central processing unit can monitor the first carbon dioxide concentration C1, the first ammonia concentration N1, the second carbon dioxide concentration C2, and the second ammonia concentration N2 to analyze and evaluate the carbon dioxide capture capacity; at the same time, the central processing unit can also evaluate the alkali production quality based on the purity NP1 and impurity content NP2 of the sodium carbonate product and the purity LP1 and impurity content LP2 of the ammonium chloride product, and then adjust the carbon dioxide capture and alkali production process parameters (such as reaction temperature, pressure, gas flow rate, gas flow rate, etc.) to adjust the carbon dioxide capture capacity. Through this integrated carbon dioxide capture and alkali production evaluation system, the carbon dioxide capture capacity and the quality of the sodium carbonate and ammonium chloride products can be evaluated, the energy utilization efficiency in the carbon dioxide capture and alkali production process can be improved, the operating costs can be reduced, the environmental pollution can be reduced, and a balance between economic and environmental benefits can be achieved.

[0055] Optionally, the carbon dioxide capture capacity includes: a first capture index and a second capture index, the first capture index CC=|C1-C2| / C1, and the second capture index CN=|N1-N2| / N1.

[0056] In the present application, the first capture index CC is an important parameter for evaluating the efficiency of the carbon dioxide capture process. By calculating the change in carbon dioxide concentration, the first capture index CC can reflect the proportion of carbon dioxide removed during the capture process. The larger the index value, the better the carbon dioxide capture effect, and vice versa. The numerical range of the first capture index CC is usually between 0 and 1. If the first capture index CC is close to 1, it indicates that the carbon dioxide in the reaction tower is almost completely captured and the capture efficiency is very high. If the first capture index CC is close to 0, there may be incomplete capture or unstable system operation. By real-time monitoring of the first capture index CC, the carbon dioxide capture alkali production process parameters (such as reaction temperature, pressure, gas flow rate, gas flow rate, etc.) can be adjusted to optimize and improve the capture efficiency of carbon dioxide, thereby reducing carbon dioxide emissions.

[0057] In the present application, the second capture index CN is used to evaluate the consumption of ammonia in the carbon dioxide capture process. The second capture index CN indirectly reflects the degree of reaction between carbon dioxide and ammonia through the change of ammonia. The numerical range of the second capture index CN is usually between 0 and 1. If the ammonia concentration changes greatly, it means that more ammonia is used in the reaction, which indirectly indicates that the capture effect of carbon dioxide is better; conversely, insufficient consumption of ammonia may lead to incomplete reaction, which indirectly indicates that the capture efficiency of carbon dioxide is reduced. By real-time monitoring of the second capture index CN, the carbon dioxide capture alkali production process parameters (such as reaction temperature, pressure, gas flow rate, gas flow rate, etc.) can be adjusted to optimize the capture efficiency of carbon dioxide.

[0058] Therefore, in the present application, the first capture index CC and the second capture index CN provide a quantitative evaluation standard for the carbon dioxide capture capacity, which can reflect the capture efficiency of carbon dioxide and ammonia and the need to adjust the carbon dioxide capture alkali production process parameters.

[0059] Optionally, the alkali production quality includes: a first quality index and a second quality index, the first quality index QC = |NP1-NP2| / NP1, and the second quality index QL = |LP1-LP2| / LP1.

[0060] In the present application, the first quality index QC is used to evaluate the quality of the sodium carbonate Na2CO3 product in the alkali production process, and the first quality index QC can measure the efficiency of converting raw materials into alkali production products. If the first quality index QC value is close to 1, it means that the sodium carbonate Na2CO3 product conversion rate in the alkali production process is higher. If the first quality index QC value is much lower than 1, it may indicate that the reaction is incomplete, the material utilization rate is low, and the production efficiency is low. The first quality index QC can be monitored in real time, and the carbon dioxide capture alkali production process parameters (such as reaction temperature, pressure, gas flow rate, gas flow rate, etc.) can be appropriately and dynamically adjusted to ensure the production efficiency and high quality of sodium carbonate.

[0061] In the present application, the second quality index QL is used to measure the purity and quality of ammonium chloride. The second quality index QL reflects the change in ammonium chloride purity during the alkali production process. The closer the second quality index QL is to 1, the higher the purity of the ammonium chloride and the better the quality control during the alkali production process. If the second quality index QL value is low, it indicates that the impurity content in the ammonium chloride is high, which may be caused by improper control of reaction conditions or an insufficient separation process. By real-time monitoring of the second quality index QL, the system can adjust process parameters such as the cooling crystallization temperature and reaction time to improve the purity of the ammonium chloride.

[0062] Thus, in the present application, the first quality index QC and the second quality index QL provide quality control standards for the sodium carbonate yield and ammonium chloride purity, respectively, during the alkali production process. Through real-time monitoring and data feedback of the first quality index QC and the second quality index QL, reaction conditions can be adjusted to improve the sodium carbonate yield and ammonium chloride purity, thereby ensuring the quality of the final product and meeting market and industry demands, thereby achieving higher economic benefits for the entire production process.

[0063] Optionally, when CC≥99% and CN≥98%, the carbon dioxide capture capacity is evaluated to be qualified, and when QC≥99% and QL≥96%, the alkali production quality is evaluated to be qualified.

[0064] In this application, to ensure the efficiency and quality of the CO2 capture and alkali production processes, the system sets strict standards to evaluate the CO2 capture capacity and the quality of the alkali products. When the capture efficiency and product quality meet specific thresholds, the evaluation result is "qualified", thus optimizing and sustaining the entire process. Specifically, the evaluation criteria are as follows:

[0065] In this application, the first capture index (CC) is ≥99%, indicating that the CO2 capture efficiency within the first reaction tower has reached an extremely high level, with a CO2 removal rate of nearly 100%. This result indicates that there is virtually no leakage or uncaptured CO2 during the capture process, minimizing the negative impact of the entire process on the atmospheric environment. Furthermore, the second capture index (CN) is ≥98%, indicating that the reaction between ammonia and CO2 is essentially ideal. Ammonia consumption meets the reaction requirements, and the reaction process is stable and balanced, improving the efficiency of CO2 capture.

[0066] In this application, a first quality index (QC) of ≥99% indicates that the sodium carbonate produced is of very high purity, meeting industrial requirements and containing very low impurities. High-purity sodium carbonate exhibits greater activity in chemical reactions, meeting the demands of applications requiring high purity. Furthermore, a second quality index (QL) of ≥96% indicates that the ammonium chloride produced is of high purity, which can enhance its value in the agricultural and chemical industries.

[0067] Second, as Figure 2 As shown, a carbon dioxide capture alkali production evaluation method, using or not using any one of the carbon dioxide capture alkali production evaluation systems of the first aspect, comprises:

[0068] Step S100: monitoring a first carbon dioxide concentration C1 of carbon dioxide in the industrial waste gas entering the first reaction tower and sending the result to the central processing unit; monitoring a first ammonia concentration N1 of ammonia in the industrial waste gas entering the first reaction tower and sending the result to the central processing unit;

[0069] Step S200: A first reaction tower captures carbon dioxide and ammonia in the industrial waste gas and reacts them to generate ammonium carbonate; a second carbon dioxide concentration C2 in the first reaction tower is monitored after the capture reaction is completed and sent to the central processing unit; a second ammonia concentration N2 in the first reaction tower is monitored after the capture reaction is completed and sent to the central processing unit;

[0070] Step S300: reacting ammonium carbonate with a sodium chloride solution to generate sodium bicarbonate and ammonium chloride, separating the sodium bicarbonate and ammonium chloride, heating the sodium bicarbonate to generate a sodium carbonate product, and cooling and crystallizing the ammonium chloride to generate an ammonium chloride product;

[0071] Step S400: monitor the purity NP1 and impurity content NP2 of the sodium carbonate product and send them to the central processing unit; monitor the purity LP1 and impurity content LP2 of the ammonium chloride product and send them to the central processing unit;

[0072] Step S500: The central processing unit evaluates the carbon dioxide capture capacity based on the first carbon dioxide concentration C1, the first ammonia concentration N1, the second carbon dioxide concentration C2, and the second ammonia concentration N2; and evaluates the alkali production quality based on the purity NP1 and impurity content NP2 of the sodium carbonate product and the purity LP1 and impurity content LP1 of the ammonium chloride product.

[0073] Optionally, in step S500, the carbon dioxide capture capability includes: a first capture index and a second capture index, the first capture index CC=|C1-C2| / C1, and the second capture index CN=|N1-N2| / N1.

[0074] In the present application, the first capture index CC can reflect the proportion of carbon dioxide removed during the capture process. The smaller the index value, the better the carbon dioxide capture effect, and vice versa. The numerical range of the first capture index CC is usually between 0 and 1. If the first capture index CC is close to 1, it indicates that the carbon dioxide in the reaction tower is almost completely captured and the capture efficiency is very high. If the first capture index CC is close to 0, there may be incomplete capture or unstable system operation; at the same time, the second capture index CN reflects the change of ammonia during the reaction, thereby indirectly reflecting the degree of reaction between carbon dioxide and ammonia. The numerical range of the second capture index CN is usually between 0 and 1. If the second capture index CN is close to 1, it means that more ammonia is used in the reaction, which indirectly indicates that the carbon dioxide capture effect is good; conversely, if the second capture index CN is close to 0, insufficient ammonia consumption may lead to incomplete reaction, which indirectly indicates that the carbon dioxide capture efficiency is reduced. Therefore, the first capture index CC and the second capture index CN provide a quantitative evaluation standard for the carbon dioxide capture capacity, which can reflect the capture efficiency of carbon dioxide and ammonia and the need to adjust the carbon dioxide capture alkali production process parameters.

[0075] Optionally, in step S500, the alkali production quality includes: a first quality index and a second quality index, the first quality index QC = |NP1-NP2| / NP1, and the second quality index QL = |LP1-LP2| / LP1.

[0076] In this application, the first quality index (QC) is used to evaluate the quality of the sodium carbonate (Na2CO3) product in the alkali production process. The first quality index (QC) measures the efficiency of converting the raw materials into the alkali product. A QC value close to 1 indicates a high conversion rate in the alkali production process, good Na2CO3 product generation efficiency, and high product quality. A QC value far below 1 may indicate incomplete reaction, low material utilization, and low production efficiency. Meanwhile, the second quality index (QL) is used to measure the purity and quality of ammonium chloride. The second quality index (QL) reflects the change in ammonium chloride purity during the alkali production process. A closer QL value to 1 indicates higher ammonium chloride purity and better quality control during the alkali production process. A lower QL value indicates a high impurity content in the ammonium chloride, which may be caused by improper reaction conditions or an inadequate separation process. Thus, the first and second quality indices (QC and QL), respectively, provide quality control standards for sodium carbonate yield and ammonium chloride purity during the alkali production process. Through real-time monitoring and data feedback of the first quality index QC and the second quality index QL, the reaction conditions can be dynamically adjusted in real time to improve the yield of sodium carbonate and the purity of ammonium chloride, thereby ensuring the high quality and high purity of the final product to meet market and industrial needs.

[0077] Optionally, when CC≥99% and CN≥98%, the carbon dioxide capture capacity is evaluated to be qualified, and when QC≥99% and QL≥96%, the alkali production quality is evaluated to be qualified.

[0078] In this application, if both the CO2 capture capacity and the alkali product quality meet the aforementioned evaluation criteria, the entire CO2 capture and alkali production process will be considered "qualified," meaning that it achieves efficient CO2 capture while stably producing high-purity sodium carbonate and ammonium chloride products. The establishment of these evaluation criteria indicates that the reaction conditions can be adjusted in a timely manner through an external control system to optimize both the CO2 capture capacity and the alkali production process, ensuring the high quality and purity of the final product, meeting market and industry demands and conforming to the goals of green, low-carbon, and sustainable industrial production.

[0079] Therefore, the carbon dioxide capture alkali production evaluation method applied for in the present invention can monitor and analyze the first carbon dioxide concentration, the first ammonia concentration, the second carbon dioxide concentration, and the second ammonia concentration to evaluate the carbon dioxide capture capacity; at the same time, it can evaluate the alkali production quality based on the purity and impurity content of the sodium carbonate product and the purity and impurity content of the ammonium chloride product, thereby reducing environmental pollution and achieving a balance between economic and environmental benefits.

[0080] The above description of the present invention and its embodiments is non-limiting. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if a person skilled in the art is inspired by this and, without departing from the inventive purpose of the present invention, designs structures and embodiments similar to the technical solution without inventiveness, they shall fall within the scope of protection of the present invention.

Claims

1. A carbon dioxide capture alkali production evaluation system, comprising: A first carbon dioxide concentration monitoring unit monitors the first carbon dioxide concentration C1 of carbon dioxide in the industrial waste gas entering the first reaction tower and sends it to the central processing unit; a first ammonia concentration monitoring unit monitors the first ammonia concentration N1 of ammonia in the industrial waste gas entering the first reaction tower and sends it to the central processing unit; The first reaction tower captures carbon dioxide and ammonia in industrial waste gas and reacts them to produce ammonium carbonate; A second carbon dioxide concentration monitoring unit monitors the second carbon dioxide concentration C2 in the first reaction tower after the capture reaction is completed and sends it to the central processing unit; a second ammonia concentration monitoring unit monitors the second ammonia concentration N2 in the first reaction tower after the capture reaction is completed and sends it to the central processing unit; In the second reaction tower, ammonium carbonate reacts with sodium chloride solution to produce sodium bicarbonate and ammonium chloride, the sodium bicarbonate and ammonium chloride are separated, and the ammonium chloride is cooled and crystallized to produce an ammonium chloride product; The third reaction tower heats the sodium bicarbonate to generate a sodium carbonate product; The sodium carbonate product purity monitoring unit monitors the purity NP1 and impurity content NP2 of the sodium carbonate product and sends the results to the central processing unit; the ammonium chloride product purity monitoring unit monitors the purity LP1 and impurity content LP2 of the ammonium chloride product and sends the results to the central processing unit; The central processing unit evaluates the carbon dioxide capture capacity based on the first carbon dioxide concentration C1, the first ammonia concentration N1, the second carbon dioxide concentration C2, and the second ammonia concentration N2; and evaluates the alkali production quality based on the purity NP1 and impurity content NP2 of the sodium carbonate product and the purity LP1 and impurity content LP2 of the ammonium chloride product.

2. A carbon dioxide capture alkali production evaluation system according to claim 1, characterized in that: The carbon dioxide capture capacity includes: a first capture index and a second capture index, the first capture index CC = |C1-C2| / C1, and the second capture index CN = |N1-N2| / N1.

3. The carbon dioxide capture and alkali production evaluation system according to claim 2, characterized in that: The alkali production quality includes: a first quality index and a second quality index, the first quality index QC = |NP1-NP2| / NP1, and the second quality index QL = |LP1-LP2| / LP1.

4. The carbon dioxide capture and alkali production evaluation system according to claim 3, characterized in that: When CC≥99% and CN≥98%, the carbon dioxide capture capacity is evaluated as qualified; when QC≥99% and QL≥96%, the alkali production quality is evaluated as qualified.

5. A method for evaluating carbon dioxide capture and alkali production, comprising: Step S100: monitoring a first carbon dioxide concentration C1 of carbon dioxide in the industrial waste gas entering the first reaction tower and sending the result to the central processing unit; monitoring a first ammonia concentration N1 of ammonia in the industrial waste gas entering the first reaction tower and sending the result to the central processing unit; Step S200: A first reaction tower captures carbon dioxide and ammonia in the industrial waste gas and reacts them to generate ammonium carbonate; a second carbon dioxide concentration C2 in the first reaction tower is monitored after the capture reaction is completed and sent to the central processing unit; a second ammonia concentration N2 in the first reaction tower is monitored after the capture reaction is completed and sent to the central processing unit; Step S300: reacting ammonium carbonate with a sodium chloride solution to generate sodium bicarbonate and ammonium chloride, separating the sodium bicarbonate and ammonium chloride, heating the sodium bicarbonate to generate a sodium carbonate product, and cooling and crystallizing the ammonium chloride to generate an ammonium chloride product; Step S400: monitor the purity NP1 and impurity content NP2 of the sodium carbonate product and send them to the central processing unit; monitor the purity LP1 and impurity content LP2 of the ammonium chloride product and send them to the central processing unit; Step S500: The central processing unit evaluates the carbon dioxide capture capacity based on the first carbon dioxide concentration C1, the first ammonia concentration N1, the second carbon dioxide concentration C2, and the second ammonia concentration N2; and evaluates the alkali production quality based on the purity NP1 and impurity content NP2 of the sodium carbonate product and the purity LP1 and impurity content LP1 of the ammonium chloride product.

6. The method for evaluating carbon dioxide capture and alkali production according to claim 5, wherein: In step S500 , the carbon dioxide capture capability includes: a first capture index and a second capture index, wherein the first capture index CC=|C1-C2| / C1, and the second capture index CN=|N1-N2| / N1.

7. The method for evaluating carbon dioxide capture and alkali production according to claim 6, wherein: In step S500 , the alkali production quality includes: a first quality index and a second quality index, the first quality index QC=|NP1-NP2| / NP1, and the second quality index QL=|LP1-LP2| / LP1.

8. The method for evaluating carbon dioxide capture and alkali production according to claim 7, wherein: In step S500, when CC≥99% and CN≥98%, the carbon dioxide capture capacity is evaluated to be qualified, and when QC≥99% and QL≥96%, the alkali production quality is evaluated to be qualified.

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