A device and method for detecting phase separation in a phase separation liquid

Abstract

The present invention discloses a detection device and method for phase separation in a phase-separated liquid. The detection device includes a probe sleeve, a probe, a probe connecting line, and a control and analysis device. The probe sleeve is vertically fixed in the phase-separated liquid. The wall of the probe sleeve is connected with a plurality of hollow transverse tubes. The probe is placed inside the probe sleeve. The probe is provided with a sensor. The probe connecting line is used to connect the probe and the control and analysis device, and transmit the signal detected by the probe to the control and analysis device. The control and analysis device is used to control the movement of the probe, and receive and analyze the signal detected by the probe, thereby obtaining the phase separation. The present invention can obtain an accurate sensing signal through the cooperation of the probe and the probe sleeve, and then use the control and analysis device to analyze the sensing signal, so as to efficiently and accurately obtain the phase separation of the phase-separated liquid. The detection device has a simple structure and low production cost, is suitable for large-scale promotion, and has a good monitoring and control effect on the carbon capture operation process.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of phase separation detection, and particularly relates to a device and a method for detecting the phase separation condition of a phase separation liquid. BACKGROUND

[0002] Coal-fired power plants, steel plants, cement plants and other major carbon-emitting industrial sources can achieve large-scale carbon dioxide emission reduction through carbon capture technology. Among various carbon capture technologies, chemical absorption method carbon capture is the most mature and has the broadest application prospect. After years of development, the third-generation two-phase absorbent has attracted widespread attention due to its significant energy saving and cost reduction advantages.

[0003] After absorbing CO2, the two-phase absorbent will undergo phase separation to form a CO2-rich aqueous phase and an organic phase containing almost no CO2. Only the CO2-rich aqueous phase needs to be desorbed to achieve CO2 capture, which can significantly reduce the energy consumption of desorption. The phase separation behavior of the two-phase absorbent after absorbing CO2 is influenced by various factors, including absorption load, viscosity, temperature, etc. Maintaining a stable phase separation state is the basis for the efficient operation of the entire carbon capture system, and this cannot be achieved without phase separation detection and monitoring of the two-phase absorbent. As a new generation of capture technology, there is currently a lack of efficient phase separation detection and monitoring technology for two-phase absorbents.

[0004] Some studies have proposed a phase separation interface detection method that uses multiple length-decreasing conductivity electrodes to measure the conductivity between adjacent electrodes in real time. However, this measurement method requires multiple conductivity electrodes for detection, and as the volume of the phase separator increases, the number of electrodes needed also increases. This makes it inconvenient and significantly increases the cost for industrial large-capacity carbon capture devices. Moreover, the distribution of numerous electrodes is easily affected by the flow of the solution in the phase separation tank, and the simultaneous movement of all electrodes can disturb the solution and affect the measurement results.

[0005] Some studies have proposed a method that uses an image camera to capture the glass observation window on the phase separation tank, and uses picture recognition to analyze the changes in the phase separation interface. However, this measurement method is greatly affected by the external light in the phase separation tank and the color difference between the upper and lower phases, making it prone to inaccurate recognition. At the same time, it requires the phase separation interface to be within the range of the glass window, limiting the phase separation ratio range of the solution. In addition, this method can only sense whether the solution is phase-separated and cannot sense the situation before and after the solution will phase separate or the phase separation interface disappears, which is not conducive to prior adjustment. SUMMARY

[0006] To overcome the problems of complex device, poor practicability and high cost in the phase separation detection and monitoring methods of the prior art, one of the purposes of the present application is to provide a device for detecting the phase separation condition of a phase separation liquid, which can accurately and efficiently detect the phase separation condition of the phase separation liquid.

[0007] The second object of the present application is to provide a method for detecting the phase separation of a phase separation liquid.

[0008] The third object of the present application is to provide a method for monitoring and regulating the carbon capture operation process.

[0009] To achieve the above object, the technical solution adopted by the present application is as follows:

[0010] The first aspect of the present application provides a device for detecting the phase separation of a phase separation liquid, comprising a probe sleeve, a probe, a probe connecting line and a control analysis device.

[0011] The probe sleeve is vertically fixed in the phase separation liquid; the tube wall of the probe sleeve is connected with a plurality of hollow transverse tubes;

[0012] The probe is placed inside the probe sleeve; the probe is provided with a sensor;

[0013] The probe connecting line is used to connect the probe and the control analysis device, and transmit the signal detected by the probe to the control analysis device;

[0014] The control analysis device is used to control the movement of the probe, and receive and analyze the signal detected by the probe, so as to obtain the phase separation.

[0015] In the detection device of the present application, the probe sleeve connected with the hollow transverse tubes is provided, which on the one hand makes the probe only move up and down in the probe sleeve, avoiding the influence of the liquid in the phase separation liquid on the horizontal position of the probe, and on the other hand makes the phase separation liquid smoothly enter the probe sleeve through the hollow transverse tubes on the tube wall of the probe sleeve to contact the probe, and reduces the phenomenon of mutual mixing of the upper and lower layers of the phase separation liquid caused by the upward and downward movement of the probe, thereby effectively improving the measurement accuracy. Moreover, combined with the analysis of the detection signal of the probe by the detection analysis module, the phase separation can be accurately obtained, which provides effective support for the analysis and regulation of the subsequent phase separation behavior.

[0016] In the present application, the phase separation liquid refers to a liquid that is separated from a homogeneous liquid phase under certain conditions (such as specific temperature, pressure, reaction, operation, etc.) to form two or more immiscible liquid phases. Specifically, such as: an oil-water mixture, which can be separated into oil and water phases after standing; a carbon capture two-phase absorbent, which can form a CO2-rich phase and a CO2-lean phase when the absorption of CO2 reaches the phase separation load, etc.

[0017] In some specific embodiments of the present application, the control analysis device comprises a receiving and releasing module and a detection analysis module connected thereto; the receiving and releasing module and the detection analysis module are connected through the probe connecting line; the receiving and releasing module is used to control the movement of the probe; and the detection analysis module is used to receive and analyze the signal detected by the probe.

[0018] In some more specific embodiments of the present application, the probe is further configured to record the position height signal of the probe and transmit the position height signal of the probe to the detection and analysis module; and the signal transmission can be achieved through the probe connecting line.

[0019] In some specific embodiments of the present application, the probe retraction module comprises a recovery cavity and a control motor; the recovery cavity is configured to accommodate the probe connecting line; the control motor is connected to the detection and analysis module through a signal line; and the detection and analysis module controls the control motor through the signal line to achieve the retraction and extension of the probe connecting line and drive the movement of the probe.

[0020] In some more specific embodiments of the present application, the control motor rotates forward to lift the probe; and the control motor reverses to lower the probe.

[0021] In some specific embodiments of the present application, the sensor is an electrical conductivity sensor; and the signal is electrical conductivity.

[0022] Since the ion concentration between the two phases in the phase separation liquid is usually different, resulting in different electrical conductivity, the ion concentration intensity in the solution can be reflected through the electrical conductivity, so as to determine the phase separation of the phase separation liquid.

[0023] In some more specific embodiments of the present application, the electrical conductivity sensor comprises at least one of an electrode type electrical conductivity sensor, an inductance type electrical conductivity sensor or an ultrasonic electrical conductivity sensor; and the electrode type electrical conductivity sensor is preferred.

[0024] In some specific embodiments of the present application, the phase separation liquid is a flowing phase separation liquid or a static phase separation liquid; and in some more specific embodiments of the present application, the phase separation liquid is a flowing phase separation liquid.

[0025] It should be noted that the detection device of the present application can be suitable for both flowing phase separation liquid and static phase separation liquid. However, there is no simple and efficient detection device for flowing phase separation liquid in the prior art. When the detection device of the present application is suitable for flowing phase separation liquid, it can achieve better detection effect compared with the prior art.

[0026] In some specific embodiments of the present application, the phase separation liquid is a phase separation liquid in a phase separation container (such as a phase separation liquid in a phase separation tank in a carbon capture system), and the probe sleeve is vertically fixed in the phase separation container and in contact with the inner bottom of the phase separation container; further, the phase separation container has a top opening, and the probe sleeve is in communication with the top opening of the phase separation container.

[0027] In some specific embodiments of the present application, the phase separation liquid is a carbon capture two-phase absorbent.

[0028] After the carbon capture two-phase absorbent absorbs carbon dioxide and undergoes phase separation, a large conductivity difference will be generated between the two phases of the two-phase absorbent. The present invention is particularly suitable for detecting the phase separation of the carbon capture two-phase absorbent and can achieve higher detection sensitivity.

[0029] In some specific embodiments of the present invention, the inner diameter of the probe sleeve is R; the inner diameter of the hollow transverse tube is ≤R; and the distribution spacing of the hollow transverse tubes on the wall of the probe sleeve is ≤2R.

[0030] By adjusting the inner diameter and distribution spacing of the hollow horizontal tube, the phase separation liquid can smoothly enter the probe sleeve and contact the probe, and the phenomenon of the upper and lower layers of the phase separation liquid being mixed with each other due to the up and down movement of the probe can be reduced, thereby improving the detection accuracy.

[0031] In the present invention, multiple hollow transverse tubes refer to two or more hollow transverse tubes. The specific number can be set according to the actual situation or actual needs of the phase separation liquid, and the present invention does not make any specific limitation.

[0032] In the present invention, the hollow transverse tubes can be distributed in various forms on the wall of the probe sleeve, and can be distributed at equal intervals or at unequal intervals. This can be set according to the actual situation or actual needs of the phase separation liquid, and the present invention does not make any specific limitations.

[0033] In some embodiments of the present invention, the probe cable includes an inner layer and an outer layer covering the inner layer; the outer layer is a corrosion-resistant coating material; and the inner layer is a sensor signal line. In some embodiments of the present invention, the inner layer may be a conductivity sensor signal line; the outer layer may be an acid- and alkali-resistant coating material. The present invention utilizes a double-layer probe cable configuration, with a corrosion-resistant coating on the outer surface of the sensor signal line to protect the inner layer and provide support.

[0034] The second aspect of the present invention provides a method for detecting the phase separation situation in the phase separation liquid, which is performed by the detection device described in the first aspect of the present invention, and includes the following steps: adjusting the control and analysis device so that the probe is lowered to the bottom of the phase separation liquid and set to the zero position; adjusting the control and analysis device so that the probe moves up and down in the probe sleeve, and at the same time records the height of the probe relative to the zero position; during the up and down movement of the probe, a sensor signal is obtained through the sensor of the probe, and the sensor signal is transmitted to the control and analysis device through the probe connecting line; using the control and analysis device to analyze the sensor signal to obtain a relationship diagram between the sensor signal and the probe height, thereby obtaining the phase separation situation of the phase separation liquid.

[0035] In some specific embodiments of the present invention, the phase separation condition of the phase-separated liquid includes the phase separation state of the phase-separated liquid and / or the position of the phase separation interface after the phase separation; specifically, the phase separation state of the phase-separated liquid includes no phase separation, about to phase separation, phase separation, etc.; the phase separation interface after the phase separation of the phase-separated liquid is located at the position of the probe when the sensor signal jumps.

[0036] For phase-separated liquids, the sensor signals on both sides of the phase interface after phase separation will undergo significant changes. When the probe enters the other phase from one phase, the sensor signal will change significantly. The position of the probe when the sensor signal jumps corresponds to the phase interface. Taking the carbon capture two-phase absorbent as an example, after absorbing CO2, it undergoes phase separation. The CO2-rich aqueous phase formed contains a large amount of carbonate, bicarbonate, carbamate ions, etc. Therefore, the conductivity of the CO2-rich aqueous phase is relatively high, while the ion concentration contained in the other layer of CO2-lean organic phase is very low, and the conductivity is very low. When the probe enters the CO2-lean organic phase from the CO2-rich aqueous phase, or from the CO2-lean organic phase into the CO2-rich aqueous phase, the conductivity will change significantly. The position of the probe when the conductivity jumps corresponds to the phase interface. In the present invention, the jump can be a change of ≥20% in the sensor signal, for example, it can be any value among 20%, 40%, 50%, 80%, 100%, or a range of values ​​between any two.

[0037] In some specific embodiments of the present invention, the time required for the probe to rise from the bottom of the phase separation liquid to the top of the phase separation liquid is t, t≤10s; in some specific embodiments of the present invention, t≤5s; for example, it can be any value of 1s, 2s, 3s, 4s or 5s or a range value between any two of them.

[0038] The moving speed of the probe in the probe sleeve is related to the internal height of the phase-separated liquid. Since the probe sleeve is provided in the present invention, the moving speed of the probe is less affected by the liquid flow, so a faster probe moving speed can be used, which greatly shortens the detection time and achieves efficient and accurate detection.

[0039] The third aspect of the present invention provides a method for monitoring and controlling a carbon capture operation process, which is characterized in that it is performed by the detection device described in the first aspect of the present invention, or by the detection method described in the second aspect of the present invention, and includes the following steps: monitoring the phase separation of the two-phase absorbent during the carbon capture operation process through the detection device or the detection method, and regulating the carbon capture operation process based on the monitored situation.

[0040] In some embodiments of the present invention, the monitoring method includes a continuous monitoring mode, a hybrid monitoring mode or a combination thereof:

[0041] The continuous monitoring mode is that during the carbon capture operation, the probe is controlled to move up and down periodically in the two-phase absorbent, and a relationship diagram of the sensing signal at different times and the probe height is obtained, so that the phase separation of the two-phase absorbent at different times is obtained.

[0042] The mixed monitoring mode is that during the carbon capture operation, when the two-phase absorbent has a phase separation interface, the probe is controlled to be fixed on one side of the phase separation interface in the two-phase absorbent, and the sensing signal at the position is monitored in real time, when the sensing signal at the position changes, the probe is adjusted to move up and down once, and a relationship diagram of the sensing signal at this time and the probe height is obtained, so that the phase separation interface of the two-phase absorbent at each sensing signal change is obtained.

[0043] Through the continuous monitoring mode or the mixed monitoring mode, the phase separation can be monitored, whether the phase separation interface deviates, whether the phase separation behavior develops to phase separation or phase separation disappears, and the like, so as to provide support for the phase separation behavior adjustment, and facilitate the pre-adjustment.

[0044] In some specific embodiments of the present application, the method for adjusting the carbon capture operation based on the monitoring situation includes: when the monitoring situation is that the two-phase absorbent has a phase separation interface and the phase separation interface deviates, adjusting the CO2 load of the two-phase absorbent and / or the volume of the upper and lower phases of the two-phase absorbent (specifically, adjusting the solution flow rate of the phase separation tank) to adjust the phase separation interface; when the monitoring situation is that the two-phase absorbent has a phase separation interface and the phase separation interface does not deviate, but the sensing signal on one side of the phase separation interface changes, adjusting the CO2 load of the two-phase absorbent to adjust the sensing signal; when the monitoring situation is that the two-phase absorbent has a phase separation interface and the phase separation interface does not deviate, and the sensing signal on one side of the phase separation interface does not change, no adjustment is performed. Specifically, adjusting the CO2 load of the two-phase absorbent can be achieved by adjusting the carbon capture process, such as adjusting the CO2 flow rate of the carbon capture process.

[0045] The detection device or the detection method provided by the present application can realize efficient and low-cost detection and monitoring of the phase separation of the two-phase absorbent, provide key support for the stable operation of the two-phase absorbent, and provide an effective adjustment method for the carbon capture operation process, thereby improving the operation efficiency of the carbon capture.

[0046] In some specific embodiments of the present application, adjusting the volume of the upper and lower phases of the two-phase absorbent can be: when the phase separation interface deviates upwards, increasing the volume of the upper phase and / or reducing the volume of the lower phase; when the phase separation interface deviates downwards, reducing the volume of the upper phase and / or increasing the volume of the lower phase. Preferably, the phase separation interface is located at the middle position of the phase separation liquid.

[0047] In some embodiments of the present application, adjusting the CO2 load of the two-phase absorbent can be achieved by adjusting the carbon capture process, such as adjusting the gas-liquid ratio of the carbon capture absorption tower to increase or decrease the CO2 load of the two-phase absorbent. Since the sensing signal on one side of the phase separation interface changes, but the phase separation interface does not change, it is possible that the CO2 load captured by the two-phase absorbent has changed. Monitoring the phase separation interface of the two-phase absorbent is beneficial for monitoring and regulating the carbon capture process, and can pre-control the carbon capture process to obtain good carbon capture efficiency.

[0048] The present application has the following advantages: the design of the probe sleeve allows the probe to move up and down in the probe sleeve, avoiding the probe from deviating in the phase separation liquid, making the measured probe height more accurate. In addition, it also avoids the disturbance of the probe moving up and down to the phase separation liquid, which leads to the mutual mixing of the upper and lower layers of the phase separation liquid, making the detection result more accurate. Through the cooperation of the probe and the probe sleeve, accurate sensing signals can be obtained. The control and analysis device can analyze the sensing signals to efficiently, simply and accurately obtain the phase separation situation of the phase separation liquid. The detection device has a simple structure, low production cost, and is suitable for large-scale promotion. It has good monitoring and regulation effect on the carbon capture operation process. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 The structure diagram of the detection device for the phase separation situation in the phase separation liquid used in some embodiments of the present application.

[0050] Figure 2 The relationship diagram between the conductivity and the probe height obtained in some embodiments of the present application.

[0051] Explanation of reference signs: 1, probe sleeve; 11, hollow horizontal pipe; 2, probe; 3, probe connecting line; 4, control and analysis device; 41, release and winding module; 42, detection and analysis module; 43, signal line; 5, phase separation tank; 51, lower phase of the two-phase absorbent; 52, upper phase of the two-phase absorbent; 53, phase separation interface of the two-phase absorbent; 54, top interface of the two-phase absorbent. DETAILED DESCRIPTION

[0052] The following further illustrates the content of the present application through specific examples. It should also be understood that the following examples are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Some non-essential improvements and adjustments made by those skilled in the art according to the principles set forth in the present application are within the scope of protection of the present application. The following examples specifically process parameters, etc. are only one example in the appropriate range, i.e. those skilled in the art can make appropriate choices within the scope of the present application, and are not limited to the specific data of the following examples. The raw materials, reagents or devices used in the following examples and comparative examples are commercially available or can be obtained by known methods unless otherwise specified.

[0053] Example 1

[0054] The detection device as shown in Figure 1 is used to monitor and control the phase separation of the two-phase absorbent in the phase separation tank. For a kiloton two-phase absorbent CO2 capture device, the internal height of the phase separation tank 5 is designed to be 1.2 m, the absorbent is an organic solvent type two-phase absorbent, the CO2-rich water phase after phase separation is in the lower layer, i.e. the lower phase 51 is the CO2-rich water phase; the CO2-lean organic phase is in the upper layer, i.e. the upper phase 52 is the CO2-lean organic phase; the absorbent also has a phase separation interface 53 and a top interface 54; the laboratory test upper and lower layer phase separation ratio of the absorbent is 54:46. The specific monitoring and control steps are as follows:

[0055] The probe sleeve 1 is vertically fixed in the phase separation tank 5, the pipe wall of the probe sleeve 1 is connected with a plurality of hollow cross pipes 11, the probe 2 and the probe connecting line 3 are put into the probe sleeve 1, according to the internal depth of the phase separation tank 5, the detection and analysis module 42 in the analysis device 4 sends a control signal through the signal line 43, the control motor in the receiving and releasing module 41 reverses, the probe 2 is lowered to the bottom of the phase separation tank 5, the zero point position is corrected, and the height of the position of the probe 2 at this time is 0.00 meters. Then the control motor in the receiving and releasing module 41 is controlled to rotate in the positive direction, the probe 2 rises, the conductivity of the solution is measured synchronously during the rising process of the probe 2, until the probe 2 rises to a height of 1 meter, the position height signal of the probe 2 generated by the rotation of the control motor and the conductivity signal measured by the probe 2 are transmitted to the detection and analysis module 42, forming a coordinate curve with the conductivity data measured by the probe 2 as the X axis and the probe position data as the Y axis, which can be specifically referred to Figure 2 , the probe position data when the conductivity data changes sharply is the height of the phase separation interface, the measured height of the phase separation interface in this example is 0.63 meters.

[0056] During the operation of the carbon capture device, a mixed monitoring mode is adopted. After the stable operation of the absorbent phase separation, the probe 2 is placed at a height of 0.4 meters, which is 0.23 meters away from the phase separation interface 53. The conductivity at this position is monitored in real time. When the conductivity deviates from the normal phase separation range, the solution is automatically detected up and down once to confirm that the phase separation interface 53 moves downward, the feed of the phase separation tank and the extraction of the CO2-lean organic phase are increased, and the phase separation interface 53 is maintained at the middle position of the phase separation tank 5.

[0057] Example 2

[0058] The detection device as shown in Figure 1 is used to monitor and control the phase separation of the two-phase absorbent in the phase separation tank. For a kiloton two-phase absorbent CO2 capture device, the internal height of the phase separation tank 5 is designed to be 1.2 m. The absorbent is an organic solvent type two-phase absorbent. After phase separation, the CO2-rich aqueous phase is in the lower layer, i.e., the lower phase 51 is the CO2-rich aqueous phase; the CO2-lean organic phase is in the upper layer, i.e., the upper phase 52 is the CO2-lean organic phase; the absorbent also has a phase separation interface 53 and a top interface 54; the laboratory test of the absorbent shows that the upper and lower layer phase separation ratio is 54%:46%. The specific monitoring and control steps are as follows:

[0059] The probe sleeve 1 is vertically fixed in the phase separation tank 5. The pipe wall of the probe sleeve 1 is connected with multiple hollow cross pipes 11. The probe 2 and the probe connecting line 3 are placed in the probe sleeve 1. According to the internal depth of the phase separation tank 5, the detection and analysis module 42 in the analysis device 4 sends a control signal through the signal line 43 to make the control motor in the receiving and releasing module 41 reverse, so as to lower the probe 2 to the bottom of the phase separation tank 5 and correct the zero position. At this time, the height of the position of the probe 2 is 0.00 meters. Then the control motor in the receiving and releasing module 41 is controlled to rotate forward, the probe 2 rises, and the conductivity of the solution is measured synchronously during the rising process of the probe 2, until the probe 2 rises to a height of 1 meter. The position height signal of the probe 2 generated by the rotation of the control motor and the conductivity signal measured by the probe 2 are transmitted to the detection and analysis module 42 to form a coordinate curve with the conductivity data measured by the probe 2 as the X axis and the position data of the probe as the Y axis. For details, please refer to Figure 2 . When the conductivity data changes sharply, the position data of the probe is the height of the phase separation interface. In this example, the measured height of the phase separation interface is 0.63 meters.

[0060] During the operation of the carbon capture device, a mixed monitoring mode is adopted. After the stable operation of the absorbent phase separation, the probe 2 is placed at a height of 0.4 meters, which is 0.23 meters away from the phase separation interface 53. The conductivity at this position is monitored in real time. When the conductivity deviates from the normal phase separation range, the solution is automatically detected up and down once to confirm that the phase separation interface 53 moves downward, the feed of the phase separation tank and the extraction of the CO2-lean organic phase are increased, and the phase separation interface 53 is maintained at the middle position of the phase separation tank 5.

[0061] Example 3

[0062] Use Figure 1 The detection device shown monitors and controls the phase separation of the two-phase absorbent in the phase separation tank. For a 1,000-ton two-phase absorbent CO2 capture unit, the internal height of the phase separation tank 5 is designed to be 1.2 meters. The absorbent is an organic solvent-based two-phase absorbent. After phase separation, the CO2-rich aqueous phase is in the upper layer, i.e., the upper phase 52 is the CO2-rich aqueous phase; the CO2-lean organic phase is in the lower layer, i.e., the lower phase 51 is the CO2-lean organic phase. The absorbent also has a phase separation interface 53 and a top interface 54. Laboratory testing of the absorbent shows a phase separation ratio of 59% to 41% between the upper and lower layers. The specific monitoring and control steps are as follows:

[0063] The probe sleeve 1 is fixed vertically in the phase separation tank 5. The wall of the probe sleeve 1 is connected with multiple hollow transverse tubes 11. The probe 2 and the probe connecting line 3 are placed in the probe sleeve 1. According to the internal depth of the phase separation tank 5, the detection and analysis module 42 in the control analysis device 4 sends a control signal through the signal line 43 to reverse the control motor in the retractable module 41 and lower the probe 2 to the bottom of the phase separation tank 5 to correct the zero position. At this time, the height of the probe position is 0.00 meters. Then the control motor in the retractable module 41 is controlled to rotate forward, and the probe 2 rises. The conductivity of the solution is measured synchronously during the rising process of the probe 2 until the probe 2 rises to a height of 1 meter. The position height signal of the probe 2 generated by the rotation of the control motor and the conductivity signal measured by the probe 2 are transmitted to the detection and analysis module 42 to form a coordinate curve with the conductivity data measured by the probe 2 as the X-axis and the probe position data as the Y-axis. For details, please refer to Figure 2 The probe position data when the conductivity data changes sharply is the phase interface height. In this example, the measured phase interface height is 0.51 meters.

[0064] During the operation of the carbon capture device, a mixed monitoring mode is adopted. After the absorbent phase separation is stably operated, the probe 2 is placed at a height of 0.7 meters and 0.19 meters away from the phase separation interface 53. The conductivity of this position is monitored in real time. When the conductivity is smaller than the normal phase separation range, the upper and lower detection of the solution is automatically completed to confirm that the phase separation interface 53 has not moved, indicating that the CO2 content in the CO2-rich water phase is decreasing, that is, the CO2 load captured by the absorbent is reduced. The gas-liquid ratio of the absorption tower is adjusted to increase the CO2 load of the absorbent.

[0065] Comparative Example 1

[0066] Use Figure 1The detection device shown monitors and regulates the phase separation of two-phase absorbents in a phase separation tank. For a kiloton two-phase absorbent CO2 capture device, the internal height of the phase separation tank 5 is designed to be 1.2 m, the absorbent is an organic solvent type two-phase absorbent, and after phase separation, the CO2-rich water phase is in the lower layer, i.e., the lower phase 51, which is the CO2-rich water phase; the CO2-lean organic phase is in the upper layer, i.e., the upper phase 52, which is the CO2-lean organic phase; the absorbent also has a phase separation interface 53 and a top interface 54; the laboratory test upper and lower layer phase separation ratio of the absorbent is 54:46. The specific monitoring and regulating steps are as follows:

[0067] The probe 2 is placed in the phase separation tank 5, and according to the internal depth of the phase separation tank 5, the detection and analysis module 42 in the control analysis device 4 sends a control signal through the signal line 43 to make the control motor in the receiving and releasing module 41 reverse, and the probe 2 is lowered to the bottom of the phase separation tank 5 to correct the zero position, at which time the height of the probe is 0.00 meters. In actual work, the liquid in the phase separation tank 5 is constantly flowing, and the probe 2 and the probe connection line 3 deviate from the horizontal line of the phase separation tank 5 under the action of the solution flow force, forming a certain deviation angle, and the 0.00 meter position of the signal feedback is not the 0.00 meter position at the bottom of the phase separation tank, resulting in a smaller measured value of the phase separation interface height. The faster the liquid flow rate in the phase separation tank, the greater the deviation, and in this example, the measured phase separation interface height is 0.58 meters, which deviates by 7.9% compared with 0.63 meters with the probe sleeve.

[0068] As can be seen, in the comparative example 1, the probe sleeve is not provided, and in the phase separation tank with flowing liquid, the detection accuracy of the phase separation interface is greatly reduced, and it is difficult to provide accurate guidance for the phase separation behavior according to the measured phase separation interface.

[0069] In summary, the probe sleeve is designed to move the probe up and down in the probe sleeve, avoiding the deviation of the probe in the phase separation liquid, making the measured probe height more accurate, and also avoiding the disturbance of the probe moving up and down to the phase separation liquid, thereby causing the upper and lower layers of the phase separation liquid to be mixed, making the detection result more accurate. Through the cooperation of the probe and the probe sleeve, accurate sensing signals can be obtained, and the control analysis device can analyze the sensing signals to efficiently, simply and accurately obtain the phase separation of the phase separation liquid, and the detection device has the advantages of simple structure, low production cost, and is suitable for large-scale promotion, especially for good monitoring and regulating effect in the carbon capture operation process.

Claims

1. A device for detecting phase separation in a phase-separated liquid, characterized in that: It includes a probe sleeve, a probe, a probe connecting line and a control and analysis device; The probe sleeve is fixed vertically in the phase separation liquid; the wall of the probe sleeve is connected with a plurality of hollow transverse tubes; The probe is placed inside the probe sleeve; the probe is provided with a sensor; The probe connecting line is used to connect the probe and the control and analysis device, and transmit the signal detected by the probe to the control and analysis device; The control and analysis device is used to control the movement of the probe, and receive and analyze the signal detected by the probe, so as to obtain the phase separation situation.

2. The detection device according to claim 1, characterized in that The control and analysis device includes a connected retractable module and a detection and analysis module; the retractable module is connected to the detection and analysis module via the probe connecting line; the retractable module is used to control the movement of the probe; the detection and analysis module is used to receive and analyze the signal detected by the probe.

3. The detection device according to claim 2, characterized in that The retraction and extension module includes a connected recovery chamber and a control motor; the recovery chamber is used to accommodate the probe connecting line; the control motor is connected to the detection and analysis module through a signal line; the detection and analysis module controls the control motor through the signal line to realize the retraction and extension of the probe connecting line and drive the movement of the probe.

4. The detection device according to claim 1, characterized in that The sensor is a conductivity sensor; the signal is conductivity; And / or, the phase separation liquid is a mobile phase separation liquid or a static phase separation liquid.

5. The detection device according to claim 1, characterized in that The inner diameter of the probe sleeve is R; the inner diameter of the hollow transverse tube is ≤R; and the distribution spacing of the hollow transverse tubes on the wall of the probe sleeve is ≤2R.

6. A method for detecting phase separation in a phase-separated liquid, characterized in that: The method is performed by a detection device according to any one of claims 1 to 5, and includes the following steps: adjusting the control and analysis device so that the probe is lowered to the bottom of the phase-separated liquid and set to the zero position; adjusting the control and analysis device so that the probe moves up and down in the probe sleeve, and recording the height of the probe relative to the zero position; during the up and down movement of the probe, a sensor signal is obtained through the sensor of the probe, and the sensor signal is transmitted to the control and analysis device through the probe connecting line; using the control and analysis device to analyze the sensor signal to obtain a relationship diagram between the sensor signal and the probe height, thereby obtaining the phase separation condition of the phase-separated liquid.

7. The detection method according to claim 6, characterized in that The phase separation condition of the phase separation liquid includes the phase separation state of the phase separation liquid and / or the position of the phase separation interface after the phase separation liquid is phase-separated; the phase separation interface after the phase separation liquid is phase-separated is located at the position of the probe when the sensor signal jumps; And / or, the time required for the probe to rise from the bottom of the phase-separated liquid to the top of the phase-separated liquid is t, and t≤10s.

8. A method for monitoring and controlling a carbon capture operation process, characterized in that: The method is performed by a detection device according to any one of claims 1 to 5, or by a detection method according to claim 6 or 7, and includes the following steps: monitoring the phase separation of the two-phase absorbent during the carbon capture operation by the detection device or the detection method, and regulating the carbon capture operation based on the monitored conditions.

9. The monitoring and control method according to claim 8, characterized in that: The monitoring mode includes continuous monitoring mode, hybrid monitoring mode or a combination thereof: The continuous monitoring mode is as follows: during the carbon capture operation, the probe is controlled to move up and down periodically in the two-phase absorbent to obtain a relationship diagram between the sensor signal and the probe height at different times, thereby obtaining the phase separation status of the two-phase absorbent at different times; The hybrid monitoring mode is as follows: during the carbon capture operation, when a phase separation interface exists in the two-phase absorbent, the probe is controlled to be fixed on one side of the phase separation interface in the two-phase absorbent, and the sensor signal at this position is monitored in real time. When the sensor signal at this position changes, the probe is adjusted to move up and down once, and a relationship diagram between the sensor signal and the probe height at this time is obtained, thereby obtaining the phase separation interface of the two-phase absorbent each time the sensor signal changes.

10. The monitoring and control method according to claim 9, characterized in that: The method of regulating the carbon capture operation process based on the monitoring situation includes: when the monitoring situation shows that a phase interface exists in the two-phase absorbent and the phase interface is offset, the phase interface is adjusted by adjusting the CO2 load of the two-phase absorbent and / or the upper and lower phase volumes of the two-phase absorbent; when the monitoring situation shows that a phase interface exists in the two-phase absorbent and the phase interface is not offset, but the sensor signal on one side of the phase interface changes, the sensor signal is adjusted by adjusting the CO2 load of the two-phase absorbent; when the monitoring situation shows that a phase interface exists in the two-phase absorbent and the phase interface is not offset, and the sensor signal on one side of the phase interface does not change, no regulation is performed.

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