A method and system for testing the gas-liquid contact area, liquid holdup and pressure drop coupling of a floating structured packing column

Abstract

The application provides a floating regular packing tower gas-liquid contact area, liquid holdup and pressure drop coupling test method and a test system, relates to the technical field of natural gas pretreatment, and can effectively guide the landing application of the green process technology of efficient mass transfer in the floating natural gas purification system by systematically exploring the mass transfer performance change law of the regular packing tower under the multi-degree-of-freedom motion working condition of the floating body, significantly optimizes the gas-liquid mass transfer matching state in the tower, reduces the unit product energy consumption in the natural gas purification treatment process, and realizes the green and efficient production of offshore natural gas.

Description

Technical Field

[0001] This invention relates to the technical field of natural gas pretreatment, and more particularly to a method and system for testing the coupling of gas-liquid contact area, liquid holdup, and pressure drop in a floating structured packed tower. Background Technology

[0002] Natural gas, as a high-quality, low-carbon, and clean energy source, is a core energy category for the green transformation of the global energy structure. With the iterative upgrading of offshore oil and gas development technologies, floating liquefied natural gas production, storage and offloading (FLNG) technology, with its advantages of adaptability to deep-sea development, flexible construction, and strong economic efficiency, has been widely applied in the field of deep-sea natural gas extraction. It has effectively improved the development efficiency of deep-sea natural gas resources and significantly reduced energy consumption and overall costs in offshore natural gas production and transportation, and has become a core technological support for the large-scale development of offshore natural gas in my country.

[0003] Structured packed towers are the core mass transfer equipment in offshore floating natural gas purification processes. They primarily remove acidic components such as carbon dioxide, sulfur dioxide, and hydrogen sulfide from natural gas. Their mass transfer performance directly determines the quality of the purified natural gas and is crucial for ensuring the stable and safe operation of subsequent natural gas liquefaction processes. Under conventional onshore stationary operating conditions, structured packed towers exhibit stable gas-liquid two-phase flow and excellent mass transfer efficiency, meeting the process requirements for natural gas purification.

[0004] However, FLNG operating platforms operate in complex marine environments for extended periods. The combined effects of sea winds, waves, and currents cause the floating body to exhibit six degrees of freedom of irregular motion, including rolling, pitching, and heaving. This severely disrupts the gas-liquid two-phase flow within the tower, leading to a series of technical challenges. The dynamic swaying of the floating body completely disrupts the steady-state flow system of the gas-liquid two-phase flow within the structured packed tower, resulting in uneven fluid distribution, liquid film breakage, and insufficient gas-liquid contact. This directly causes a significant decrease in the mass transfer performance of the packed tower and a marked reduction in purification efficiency.

[0005] Experimental testing has verified that, under typical floating buoy rolling conditions, the carbon dioxide content in natural gas purified by existing structured packed towers can reach up to 250 ppm, while the limit for carbon dioxide impurities in natural gas liquefaction processes is no more than 50 ppm. The actual impurity content far exceeds the process standard requirements. Excessive acidic components in natural gas not only severely affect the operational stability of subsequent liquefaction processes, easily causing equipment corrosion and process failures, threatening the operational safety of the entire FLNG production system, but also lead to incomplete natural gas purification, reduced energy utilization efficiency, and additional carbon emission burdens during production. This contradicts the original intention of using natural gas as a clean energy source and seriously restricts the high-quality development of deep-sea floating natural gas development technology.

[0006] At present, the industry lacks a testing system and method for the mass transfer performance of structured packed towers that are specifically adapted to the dynamic motion of floating bodies. It is impossible to accurately quantify the impact of floating body motion on the mass transfer efficiency inside the tower, making it difficult to accurately locate equipment operation defects. Consequently, it is impossible to effectively optimize the internal mass transfer parameters of packed towers under floating conditions, resulting in existing structured packed towers being unable to meet the production needs of complex floating conditions at sea.

[0007] In summary, to address the technical challenges of declining mass transfer performance, excessive acid components in natural gas, and poor process safety in existing technologies for structured packed towers in floating environments, and to fill the gap in specialized testing technologies for packed tower performance under floating motion conditions, it is urgent to develop a mass transfer performance testing method for structured packed towers adapted to floating environments. This will provide technical support for improving mass transfer efficiency and ensuring the stable operation of deep-sea natural gas purification and liquefaction processes. Summary of the Invention

[0008] In response to the technical problems mentioned in the background section regarding the degradation of mass transfer performance, excessive acid components in natural gas, and poor process safety in existing structuresd packed towers operating in floating environments, this invention provides a coupled testing method and system for gas-liquid contact area, liquid holdup, and pressure drop in floating structuresd packed towers. This invention utilizes a liquid transport unit, a gas transport unit, and a measurement and recording unit to experimentally determine the gas-liquid contact area—a key mass transfer performance indicator of the packed tower. Simultaneously, under static and floating body motion conditions, it simulates the offshore production environment to study the influence of the floating body's multi-degree-of-freedom motion on the packed tower performance. Based on the experimental data, it establishes a quantitative relationship between gas-liquid operating conditions and floating body motion parameters, providing a reference for engineering optimization.

[0009] The technical means employed in this invention are as follows: A method for testing the gas-liquid contact area of ​​a floating structured packed tower, which employs... A rapid, irreversible chemical reaction system includes the following steps: Step A1: Preheat and calibrate the carbon dioxide infrared analyzer, install an impurity filter at the analyzer's inlet, and install a gas mixer and desiccant at the top and bottom of the tower, respectively. Step A2: Under the vertical static condition of the floating structured packed tower, collect data from the top of the tower. Establish static baseline concentration data for the exhaust gas concentration; Step A3: Start the six-degree-of-freedom motion platform to simulate the multi-degree-of-freedom coupled motion of a floating body at sea, and monitor the top of the tower in real time. Dynamic changes in exhaust gas concentration; Step A4, Waiting for the top of the tower After the gas concentration reaches a pseudo-steady state, the concentration time history curve is obtained, and the integral average value of the periodic changes in concentration is calculated. Step A5, based on A model for calculating the gas-liquid contact area of ​​the entire tower was constructed using the mass conservation law and the two-film mass transfer theory, and the actual gas-liquid contact area inside the tower was calculated at the same time. Step A6: Fix the gas-liquid operating conditions, compare the gas-liquid contact area obtained from static and dynamic experiments, calculate the relative change rate, and determine the strengthening or weakening effect of the floating body movement on the mass transfer performance of the packed tower based on the positive or negative change rate, thus completing the mass transfer performance test of the floating structured packed tower.

[0010] Furthermore, the calculation formula for the gas-liquid contact area calculation model is as follows: ; in, This indicates the actual gas-liquid contact area inside the tower; Indicates air velocity; Indicates the overall gas-phase mass transfer coefficient; Indicates the height of the packing layer; Represents the gas constant; Indicates temperature; Indicates air intake at the bottom of the tower mole fraction; Indicates air escaping from the top of the tower. The mole fraction.

[0011] Furthermore, the formula for calculating the relative rate of change is: ; in, Indicates the relative rate of change; This represents the gas-liquid contact area in a dynamic experiment. This represents the gas-liquid contact area in a static experiment. when At that time, it was determined that the movement of the floating body reduced the gas-liquid contact area, thus deteriorating the overall mass transfer performance of the tower; when At that time, it was determined that the motion of the floating body enhanced the gas-liquid contact area and improved the mass transfer performance; when When the motion of the floating body does not change the gas-liquid contact area, the mass transfer performance remains unchanged.

[0012] This invention also includes a coupled testing method for liquid holdup and pressure drop in a floating structured packed tower, employing an air-water two-phase testing system. The test is completed using a liquid phase control component, a gas phase control component, a property adjustment component, and a six-degree-of-freedom motion platform, and includes the following steps: Step B1: Control the spray density of the liquid phase using a circulating water pump and an electromagnetic flowmeter, ensuring the flow error is <0.2%; adjust the gas phase velocity using a centrifugal fan and a vortex flowmeter; adjust the liquid phase properties by adding glycerol or a surfactant to control the liquid phase viscosity. Surface tension control at The physical properties were calibrated using an Anton-Paar advanced physical and chemical property tester. Step B2: Obtain the reference liquid holdup data in the tower under static conditions by using the cut-off venting method, collect static pressure drop data by using high-precision differential pressure sensors arranged above and below the packing section, and combine wavelet analysis to separate the inherent pressure drop and system noise to obtain the static pressure drop parameters. Step B3: Using a six-degree-of-freedom motion platform, simulate multi-degree-of-freedom coupled marine motion conditions, and use the inlet and outlet flow difference method to synchronously monitor the instantaneous flow rates at the inlet and outlet of the tower, and calculate the dynamic change data of the liquid holdup in the tower; combine wavelet analysis to separate the periodic pressure fluctuations caused by the motion of the floating body, and obtain effective data of dynamic pressure drop. Step B4: Quantitatively analyze the variation patterns of liquid holdup and pressure drop under different sea state motion parameters, and complete the quantitative test of the impact of floating body motion on the flow and mass transfer performance of the packed tower.

[0013] Furthermore, the parameters of the test include: liquid phase spray density. gas phase flow rate , floating body rolling amplitude sway / heavy oscillation amplitude exercise cycle Multi-degree-of-freedom phase difference .

[0014] Furthermore, the dynamic liquid holdup is calculated as follows: by integrating the difference between the instantaneous flow rate of the liquid phase at the inlet and the instantaneous flow rate of the liquid phase at the outlet of the tower, the real-time liquid holdup at different motion times is obtained, and the dynamic time history curve of the liquid holdup is fitted.

[0015] Furthermore, the dynamic pressure drop data processing method is as follows: the original dynamic pressure drop data is denoised and separated by wavelet analysis to obtain the periodic pressure drop fluctuation characteristic parameters generated by the multi-degree-of-freedom motion coupling of the floating body.

[0016] This invention also includes a marine integrated mass transfer performance testing system for floating structured packed towers, comprising: The floating body motion simulation module includes: a six-degree-of-freedom motion platform, used to simulate the multi-degree-of-freedom coupled motion of a floating body at sea, including roll, sway, and heave. The gas phase mass transfer detection module includes: a carbon dioxide infrared analyzer, a micro sampling pump, an impurity filter, a gas mixer, and a desiccant, used to acquire, purify, and detect the CO2 gas concentration inside the tower; The liquid phase mass transfer control module includes: a circulating water pump, an electromagnetic flow meter, a property adjustment component, and an Anton-Paar advanced physicochemical property tester; used to control liquid phase flow rate, viscosity, and surface tension parameters. The gas-liquid parameter monitoring module includes a vortex flow meter and a differential pressure sensor; the gas-liquid parameter monitoring module is used to acquire gas phase flow velocity and pressure drop data inside the tower. The data processing module acquires parameters from the floating body motion simulation module, gas phase mass transfer detection module, liquid phase mass transfer control module, and gas-liquid parameter monitoring module, and performs data calculation, noise reduction, and performance evaluation.

[0017] Furthermore, the gas sampling assembly includes a bidirectional sampling structure at the top and bottom of the tower, and a drying and filtering structure is provided in each sampling gas path.

[0018] Compared with the prior art, the present invention has the following advantages: This invention explores the changes in mass transfer performance of structured packed towers under multi-degree-of-freedom motion conditions of floating bodies. It can effectively guide the application of efficient mass transfer green process technologies in floating natural gas purification systems, significantly optimize the gas-liquid mass transfer matching state within the tower, reduce the unit product energy consumption in the natural gas purification process, and achieve green and efficient production of offshore natural gas.

[0019] Meanwhile, this invention can accurately solve core problems such as the degradation of the purification performance of the packed tower and the excessive acid components under floating conditions, ensuring the stability and controllability of the entire process of natural gas purification and liquefaction in the FLNG system, and providing solid and reliable technical support for the safe, continuous and large-scale production of floating natural gas in deep-sea areas.

[0020] Furthermore, this invention can optimize the structure and mass transfer control scheme of efficient and structured packed towers, and has good adaptability and portability to various scenarios. It can be further promoted and applied to marine engineering and industrial scenarios related to low-cost carbon capture (CCUS), greatly expanding the application boundaries of equipment and technology, and realizing the engineering reuse, value-added and sustainable industrial application of technological achievements. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the overall device of the present invention.

[0023] Figure 2 This is a schematic diagram of the process for testing the gas-liquid contact area of ​​a floating structured packed tower according to the present invention.

[0024] Figure 3 This is a schematic diagram of the process for testing the coupling of liquid holdup and pressure drop in a floating structured packed tower according to the present invention.

[0025] The components include: 1. Liquid storage tank; 2. Centrifugal water pump; 3. Regulating valve; 4. Electromagnetic flow meter; 5. Liquid distributor; 6. Gas mixer; 7. Differential pressure sensor; 8. Infrared gas analyzer; 9. Packed tower; 10. Gas distributor; 11. Vortex flow meter; 12. Six-degree-of-freedom motion platform; 13. Centrifugal fan; and 14. Frequency converter. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0027] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0028] like Figures 1-3 As shown, this invention provides a coupled testing method and system for gas-liquid contact area, liquid holdup, and pressure drop of a floating structured packed tower. This invention utilizes a liquid transport unit, a gas transport unit, and a measurement and recording unit to experimentally determine the macroscopic gas-liquid flow characteristics (liquid holdup, pressure drop, and gas-liquid contact area) of the packed tower. Under static and floating body motion conditions, it simulates the marine production environment and studies the influence of the floating body's multi-degree-of-freedom motion on the performance of the packed tower. Simultaneously, based on experimental data, it establishes a quantitative relationship between gas-liquid operating conditions and floating body motion parameters, providing a reference for engineering optimization.

[0029] As a preferred embodiment, such as Figure 1As shown, the floating body motion simulation module of the present invention includes: a six-degree-of-freedom motion platform 12, and a regular packing tower (packing tower 9) is fixedly mounted on the six-degree-of-freedom motion platform 12; the six-degree-of-freedom motion platform is used to simulate the multi-degree-of-freedom coupled marine motion conditions of the floating body at sea, including roll, sway, and heave, to reproduce the marine swaying environment and provide marine motion boundary conditions for the mass transfer performance experiment of the packing tower at sea.

[0030] The liquid phase mass transfer control module includes: a storage tank 1, a centrifugal water pump 2 (circulating water pump), a regulating valve 3, an electromagnetic flowmeter 4, a property adjustment component, and an Anton-Paar advanced physicochemical property tester. The storage tank 1 stores the liquid working medium. The centrifugal water pump 2 delivers the liquid medium to the top of the tower, where the flow rate is adjusted by the regulating valve 3. The electromagnetic flowmeter 4 collects the liquid flow rate data in real time. The property adjustment component is used to change the physicochemical parameters of the liquid medium, such as viscosity and surface tension. The Anton-Paar advanced physicochemical property tester detects the liquid phase properties. The adjusted liquid phase is then fed to the top of the packed tower 9, where it is evenly distributed by the liquid distributor 5. The liquid flows from top to bottom through the structured packing material inside the tower.

[0031] The gas phase mass transfer detection module includes: a centrifugal fan 13, a frequency converter 14, a vortex flow meter 11, a gas mixer 6, a carbon dioxide infrared analyzer (infrared gas analyzer 8), a miniature sampling pump, an impurity filter, and a desiccant. The centrifugal fan 13 serves as the gas source, with the frequency converter 14 regulating the fan's output airflow. The gas phase pipeline passes sequentially through the vortex flow meter 11 and the gas mixer 6 before entering the bottom of the packed tower 9. The gas distributor 10 distributes the gas at the bottom of the tower, and the gas flows counter-currently upwards through the packing layer, engaging in gas-liquid mass transfer contact with the sprayed liquid phase. The gas exiting the tower top is led out through a sampling branch, passing sequentially through the impurity filter and desiccant for gas purification. The miniature sampling pump then extracts a gas sample and sends it to the carbon dioxide infrared analyzer to obtain the CO2 gas concentration data at the tower's inlet and outlet.

[0032] The gas-liquid parameter monitoring module includes a vortex flow meter 11 and a differential pressure sensor 7. The vortex flow meter 11 collects the gas phase velocity parameters of the gas phase pipeline, and the differential pressure sensor 7 is connected across the upper and lower ends of the packing section of the packed tower 9 to obtain the pressure drop data inside the packed tower in real time, providing raw test data for the analysis of the system's liquid holdup and pressure drop characteristics.

[0033] The data processing module connects to the floating body motion simulation module, gas phase mass transfer detection module, liquid phase mass transfer control module, and gas-liquid parameter monitoring module. It uniformly collects all test parameters, including motion attitude signals, gas concentration, liquid phase flow rate, liquid phase properties, gas phase flow velocity, and pressure drop inside the tower. It completes the reception, calculation, and noise reduction of raw experimental data, and realizes the quantitative evaluation of the comprehensive mass transfer performance of the structured packed tower under floating conditions.

[0034] When the entire device is in operation, the six-degree-of-freedom motion platform drives the packed tower to reproduce the multi-degree-of-freedom coupled motion of the floating body at sea; the gas and liquid phases come into countercurrent contact in the packing inside the tower; each module synchronously collects multi-dimensional experimental data such as motion attitude, flow rate, pressure drop, gas composition, and liquid phase properties, and sends them to the data processing module to complete the comprehensive mass transfer performance test of the structured packed tower under marine conditions, including gas-liquid contact area, liquid holdup, and pressure drop.

[0035] In this application, the gas sampling assembly includes a bidirectional sampling structure at the top and bottom of the tower, and a drying and filtering structure is provided in each sampling gas path.

[0036] The gas sampling assembly includes a top sampling branch and a bottom sampling branch. The sampling port of the top sampling branch is located in the top gas phase space above the packing layer, and the sampling port of the bottom sampling branch is located in the bottom gas inlet area below the packing layer. They are used to collect the top gas after mass transfer through the packing layer and the bottom gas before entering the packing layer, respectively.

[0037] The top and bottom sampling branches are connected to the gas path switching assembly via sampling pipelines. The outlet of the gas path switching assembly is sequentially connected to an impurity filter, a dryer, a miniature sampling pump, and a carbon dioxide infrared analyzer. The impurity filter removes droplets, packing debris, and particulate impurities entrained in the sampled gas. The dryer contains a drying medium to reduce the water vapor content in the sampled gas, minimizing the impact of water vapor on the carbon dioxide concentration detection results. The gas path switching assembly selectively connects the top or bottom sampling branch, enabling the carbon dioxide infrared analyzer to measure the CO2 concentration in the top outlet gas and the bottom inlet gas, respectively.

[0038] like Figure 2 As shown, this invention provides a method for testing the gas-liquid contact area of ​​a floating structured packed tower, using... A rapid, irreversible chemical reaction system includes the following steps: Step A1: Preheat and calibrate the carbon dioxide infrared analyzer, install an impurity filter at the analyzer's inlet, and install a gas mixer and desiccant at the top and bottom of the tower, respectively. Step A2: Under the vertical static condition of the floating structured packed tower, collect data from the top of the tower. Establish static baseline concentration data for the exhaust gas concentration; Step A3: Start the six-degree-of-freedom motion platform to simulate the multi-degree-of-freedom coupled motion of a floating body at sea, and monitor the top of the tower in real time. Dynamic changes in exhaust gas concentration; Step A4, Waiting for the top of the tower After the gas concentration reaches a pseudo-steady state, the concentration time history curve is obtained, and the integral average value of the periodic changes in concentration is calculated. Step A5, based on A model for calculating the gas-liquid contact area of ​​the entire column is constructed based on the principles of mass conservation and the two-film mass transfer theory, and the actual gas-liquid contact area within the column is calculated simultaneously. The calculation formula for the gas-liquid contact area is as follows: ; in, This indicates the actual gas-liquid contact area inside the tower; Indicates air velocity; Indicates the overall gas-phase mass transfer coefficient; Indicates the height of the packing layer; Represents the gas constant; Indicates temperature; Indicates air intake at the bottom of the tower mole fraction; Indicates air escaping from the top of the tower. The mole fraction.

[0039] Step A6: With the gas-liquid operating conditions fixed, calculate the relative change rate by comparing the gas-liquid contact areas obtained from static and dynamic experiments. Determine the strengthening or weakening effect of the floating body movement on the mass transfer performance of the packed tower based on the sign of the change rate, thus completing the mass transfer performance test of the floating structured packed tower. In this application, the formula for calculating the relative change rate is: ; in, Indicates the relative rate of change; This represents the gas-liquid contact area in a dynamic experiment. This represents the gas-liquid contact area in a static experiment. when At that time, it was determined that the movement of the floating body reduced the gas-liquid contact area, thus deteriorating the overall mass transfer performance of the tower; when At that time, it was determined that the motion of the floating body enhanced the gas-liquid contact area and improved the mass transfer performance; when When the motion of the floating body does not change the gas-liquid contact area, the mass transfer performance remains unchanged.

[0040] like Figure 3 As shown, this invention also provides a method for coupled testing of liquid holdup and pressure drop in a floating structured packed tower. The method employs an air-water two-phase testing system, and completes the test through a liquid phase control component, a gas phase control component, a property adjustment component, and a six-degree-of-freedom motion platform. The method includes the following steps: Step B1: Control the spray density of the liquid phase using a circulating water pump and an electromagnetic flowmeter, ensuring the flow error is <0.2%; adjust the gas phase velocity using a centrifugal fan and a vortex flowmeter; adjust the liquid phase properties by adding glycerol or a surfactant to control the liquid phase viscosity. Surface tension control at The physical properties were calibrated using an Anton-Paar advanced physical and chemical property tester. Step B2: Obtain the reference liquid holdup data in the tower under static conditions by using the cut-off venting method, collect static pressure drop data by using high-precision differential pressure sensors arranged above and below the packing section, and combine wavelet analysis to separate the inherent pressure drop and system noise to obtain the static pressure drop parameters. Step B3: Using a six-degree-of-freedom motion platform, simulate multi-degree-of-freedom coupled marine motion conditions, and use the inlet and outlet flow difference method to synchronously monitor the instantaneous flow rates at the inlet and outlet of the tower, and calculate the dynamic change data of the liquid holdup in the tower; combine wavelet analysis to separate the periodic pressure fluctuations caused by the motion of the floating body, and obtain effective data of dynamic pressure drop. Step B4: Quantitatively analyze the variation patterns of liquid holdup and pressure drop under different sea state motion parameters, and complete the quantitative test of the impact of floating body motion on the flow and mass transfer performance of the packed tower.

[0041] In this application, the parameters tested include: liquid phase spray density. gas phase flow rate , floating body rolling amplitude sway / heavy oscillation amplitude exercise cycle Multi-degree-of-freedom phase difference .

[0042] Preferably, the dynamic liquid holdup is calculated as follows: by integrating the difference between the instantaneous flow rate of the liquid phase at the inlet and the instantaneous flow rate of the liquid phase at the outlet of the tower, the real-time liquid holdup at different motion times is obtained, and the dynamic time history curve of the liquid holdup is fitted.

[0043] As a preferred embodiment, in this application, the dynamic pressure drop data processing method is as follows: the original dynamic pressure drop data is denoised and separated by wavelet analysis to obtain the periodic pressure drop fluctuation characteristic parameters generated by the multi-degree-of-freedom motion coupling of the floating body.

[0044] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. In the above embodiments of the present invention, the descriptions of each embodiment have their own emphasis; parts not described in detail in a certain embodiment can be referred to in the relevant descriptions of other embodiments. It should be understood that the disclosed technical content in the several embodiments provided in this application can be implemented in other ways.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for testing the gas-liquid contact area of ​​a floating structured packed tower, characterized in that, use A rapid, irreversible chemical reaction system includes the following steps: Step A1: Preheat and calibrate the carbon dioxide infrared analyzer, install an impurity filter at the analyzer's inlet, and install a gas mixer and desiccant at the top and bottom of the tower, respectively. Step A2: Under the vertical static condition of the floating structured packed tower, collect data from the top of the tower. Establish static baseline concentration data for the exhaust gas concentration; Step A3: Start the six-degree-of-freedom motion platform to simulate the multi-degree-of-freedom coupled motion of a floating body at sea, and monitor the top of the tower in real time. Dynamic changes in exhaust gas concentration; Step A4, Waiting for the top of the tower After the gas concentration reaches a pseudo-steady state, the concentration time history curve is obtained, and the integral average value of the periodic changes in concentration is calculated. Step A5, based on A model for calculating the gas-liquid contact area of ​​the entire tower was constructed using the mass conservation law and the two-film mass transfer theory, and the actual gas-liquid contact area inside the tower was calculated at the same time. Step A6: Fix the gas-liquid operating conditions, compare the gas-liquid contact area obtained from static and dynamic experiments, calculate the relative change rate, and determine the strengthening or weakening effect of the floating body movement on the mass transfer performance of the packed tower based on the positive or negative change rate, thus completing the mass transfer performance test of the floating structured packed tower.

2. The method for testing the gas-liquid contact area of ​​a floating structured packed tower according to claim 1, characterized in that, The calculation formula for the gas-liquid contact area calculation model is as follows: ； in, This indicates the actual gas-liquid contact area inside the tower; Indicates air velocity; Indicates the overall gas-phase mass transfer coefficient; Indicates the height of the packing layer; Represents the gas constant; Indicates temperature; Indicates air intake at the bottom of the tower mole fraction; Indicates air escaping from the top of the tower. The mole fraction.

3. The method for testing the gas-liquid contact area of ​​a floating structured packed tower according to claim 1, characterized in that, The formula for calculating the relative rate of change is: ； in, Indicates the relative rate of change; This represents the gas-liquid contact area in a dynamic experiment. This represents the gas-liquid contact area in a static experiment. when At that time, it was determined that the movement of the floating body reduced the gas-liquid contact area, thus deteriorating the overall mass transfer performance of the tower; when At that time, it was determined that the motion of the floating body enhanced the gas-liquid contact area and improved the mass transfer performance; when When the motion of the floating body does not change the gas-liquid contact area, the mass transfer performance remains unchanged.

4. A method for coupled testing of liquid holdup and pressure drop in a floating structured packed tower, characterized in that, The air-water two-phase testing system was used, and the test was completed through liquid phase control components, gas phase control components, property adjustment components, and a six-degree-of-freedom motion platform, including the following steps: Step B1: Control the spray density of the liquid phase using a circulating water pump and an electromagnetic flowmeter, ensuring the flow error is <0.2%; adjust the gas phase velocity using a centrifugal fan and a vortex flowmeter; adjust the liquid phase properties by adding glycerol or a surfactant to control the liquid phase viscosity. Surface tension control at The physical properties were calibrated using an Anton-Paar advanced physical and chemical property tester. Step B2: Obtain the reference liquid holdup data in the tower under static conditions by using the cut-off venting method, collect static pressure drop data by using high-precision differential pressure sensors arranged above and below the packing section, and combine wavelet analysis to separate the inherent pressure drop and system noise to obtain the static pressure drop parameters. Step B3: Using a six-degree-of-freedom motion platform, simulate multi-degree-of-freedom coupled marine motion conditions, and use the inlet and outlet flow difference method to synchronously monitor the instantaneous flow rates at the inlet and outlet of the tower, and calculate the dynamic change data of the liquid holdup in the tower; combine wavelet analysis to separate the periodic pressure fluctuations caused by the motion of the floating body, and obtain effective data of dynamic pressure drop. Step B4: Quantitatively analyze the variation patterns of liquid holdup and pressure drop under different sea state motion parameters, and complete the quantitative test of the impact of floating body motion on the flow and mass transfer performance of the packed tower.

5. The method for coupling test of liquid holdup and pressure drop in a floating structured packed tower according to claim 4, characterized in that, The parameters tested include: liquid phase spray density. gas phase flow rate , floating body rolling amplitude sway / heavy oscillation amplitude exercise cycle Multi-degree-of-freedom phase difference .

6. The method for coupling test of liquid holdup and pressure drop in a floating structured packed tower according to claim 4, characterized in that, The dynamic liquid holdup is calculated as follows: by integrating the difference between the instantaneous flow rate of the liquid phase at the inlet and the instantaneous flow rate of the liquid phase at the outlet of the tower, the real-time liquid holdup at different motion times is obtained, and the dynamic time history curve of the liquid holdup is obtained by fitting.

7. The method for coupled testing of liquid holdup and pressure drop in a floating structured packed tower according to claim 4, characterized in that, The dynamic pressure drop data processing method is as follows: the original dynamic pressure drop data is denoised and separated by wavelet analysis to obtain the periodic pressure drop fluctuation characteristic parameters generated by the multi-degree-of-freedom motion coupling of the floating body.

8. A comprehensive mass transfer performance testing system for a floating structured packed tower at sea, characterized in that, The method for implementing the gas-liquid contact area testing method according to any one of claims 1 to 3 and the liquid holdup and pressure drop coupling testing method according to any one of claims 4 to 7 includes: The floating body motion simulation module includes: a six-degree-of-freedom motion platform, used to simulate the multi-degree-of-freedom coupled motion of a floating body at sea, including roll, sway, and heave. The gas phase mass transfer detection module includes: a carbon dioxide infrared analyzer, a micro sampling pump, an impurity filter, a gas mixer, and a desiccant, used to acquire, purify, and detect the CO2 gas concentration inside the tower; The liquid phase mass transfer control module includes: a circulating water pump, an electromagnetic flow meter, a property adjustment component, and an Anton-Paar advanced physicochemical property tester; used to control liquid phase flow rate, viscosity, and surface tension parameters. The gas-liquid parameter monitoring module includes a vortex flow meter and a differential pressure sensor; the gas-liquid parameter monitoring module is used to acquire gas phase flow velocity and pressure drop data inside the tower. The data processing module acquires parameters from the floating body motion simulation module, gas phase mass transfer detection module, liquid phase mass transfer control module, and gas-liquid parameter monitoring module, and performs data calculation, noise reduction, and performance evaluation.

9. A marine integrated mass transfer performance testing system for a floating structured packed tower according to claim 8, characterized in that, The gas sampling assembly includes a bidirectional sampling structure at the top and bottom of the tower, and a drying and filtration structure is installed in each sampling gas path.

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