An adsorption device capable of online monitoring

Abstract

The present invention relates to an adsorption device capable of online monitoring. The adsorption device comprises an online mid-infrared spectrum detection system, a branch with a test sample pool is arranged on a material pipeline that needs to be monitored online, and an online mid-infrared spectrometer is used to detect the material in the sample pool. The adsorption device capable of online monitoring of the present invention can perform real-time online detection of the material concentration in the adsorption device.

Description

Technical Field

[0001] The invention belongs to the technical field of adsorption separation, and in particular relates to an adsorption device capable of being monitored online. Background Art

[0002] Adsorption equipment is a commonly used separation equipment. Adsorption equipment includes fixed bed adsorption equipment and simulated moving bed equipment. Simulated moving bed equipment has the advantages of high production efficiency, low organic solvent consumption, large mass transfer driving force, and convenient automatic continuous production. It is widely used in petrochemical, food industry, pharmaceutical and other fields. It is a complex industrial process with many influencing factors, nonlinear, non-equilibrium, non-ideal, multi-degree-of-freedom periodic process.

[0003] The simulated moving bed divides the fixed adsorption bed into many sections, each of which is filled with adsorbent, and the liquid cannot flow directly between the sections. Each section is equipped with an inlet and outlet pipe, and its inlet and outlet are controlled by a multi-channel rotary valve. Typically, in a simulated moving bed with 8 adsorption columns, 20 of the 24 inlets and outlets only serve to connect the sections, and the other 4 are for the entry or exit of four streams of materials. The position of the material inlet and outlet at a certain moment divides the entire adsorption bed into four zones, the distance between the zones is not equal, and the mass transfer between each section is also different.

[0004] The simulated moving bed uses a multi-channel rotary valve to move the inlet and outlet of the four materials upward at a speed synchronized with the change in solid phase concentration. In this way, a closed loop is formed, and the overall result is basically the same as keeping the inlet and outlet positions stationary while the solid adsorbent moves from top to bottom in the adsorber, thereby achieving the separation effect. The core equipment to achieve this process is the multi-channel rotary valve, which is used to achieve periodic switching of the process through the rotation of the multi-channel rotary valve, thereby achieving the purpose of separating the products.

[0005] In the prior art, CN100453867C discloses a 36-way rotary valve for a high-performance liquid preparative chromatography simulated moving bed, the 36-way rotary valve is connected to a stepper motor equipped with a synchronous pulley through a belt, the 36-way rotary valve mainly includes a static plate and a cover shell installed on the static plate, a transmission shaft is arranged between the static plate and the cover shell, one end of the transmission shaft is inserted into the central hole of the static plate, the other end passes through the cover shell and is equipped with another synchronous pulley, the circumference of the static plate and the cover shell is equipped with a sealing ring and is evenly fixed; there are also a moving plate, a driving plate, a disc spring, an adjustment pad and a thrust bearing between the static plate and the cover shell from bottom to top. The 36-way rotary valve has a compact structure and a small dead volume, which greatly reduces the failure rate of the simulated moving bed equipment; however, the 36-way rotary valve is expensive and not easy to disassemble and repair. When replacing the adsorbent, the entire simulated moving bed device needs to be shut down, which reduces the long-term operation capacity of the device.

[0006] It is an existing technology to use program-controlled valves for simulated moving beds. The Axens Eluxyl simulated moving bed process and the Sorpx simulated moving bed process are also controlled by n*24 program-controlled valve groups. However, due to the different volumes of the pipelines connected to the adsorption column and the periodic changes in the relative position of the circulating pump in the area, the flow rate of the circulating pump varies greatly with the area, making it difficult to control and causing large pressure fluctuations.

[0007] In the process of production, the accuracy of process control has a great impact on the quality of the product, so it is particularly important to be able to detect the material composition online in real time. The existing adsorption equipment is only equipped with measuring devices for process conditions such as pressure and temperature, and there is no measuring device that can detect the material concentration online in real time.

[0008] Patent CN 103760131A discloses a real-time prediction method for gasoline oil properties based on near-infrared spectroscopy detection. This method requires scanning the near-infrared spectra of gasoline components C4 to C12 and building a model to calculate the octane number, but cannot directly measure the content of olefins, alkanes, and alkynes.

[0009] Patent CN 104122235A discloses an olefin gas detection device and method. This method can only detect whether various olefins are leaking in the device area, but the olefin gas detection requires gaseous olefins or olefins to be gasified before detection. The detection process is cumbersome, the pre-treatment is complicated, and quantitative detection cannot be formed.

[0010] Liang Shipu (Online infrared spectroscopy for the detection of olefins and aromatics (benzene) in gasoline, Fine Petrochemicals, Issue 4, July 2001) proposed an online infrared spectroscopy method for the detection of olefins and aromatics in gasoline. This method uses near infrared spectroscopy to detect gasoline online in the pipeline, but the applicable range of the detection sample is small, and the repeatability and reproducibility of olefin detection have large deviations. Summary of the invention

[0011] In order to solve the above technical problems, the present invention provides an adsorption device capable of online monitoring, which can perform real-time online detection of the material concentration in the adsorption device.

[0012] The technical solutions adopted are:

[0013] An adsorption device capable of online monitoring comprises an online mid-infrared spectrum detection system. A branch with a test sample pool is arranged on a material pipeline requiring online monitoring, and an online mid-infrared spectrometer is used to detect the material in the sample pool.

[0014] Preferably, an online mid-infrared spectroscopy detection system can be used to detect the content of olefins, alkanes and alkynes in the material of the adsorption device in real time.

[0015] The mid-infrared spectrometer uses a fiber optic probe for measurement, with a spectral range of 4000-650cm -1 , resolution 4cm -1 .

[0016] The mid-infrared spectrum detection system can be arranged on the inlet and outlet pipelines of the adsorption device.

[0017] Furthermore, the adsorption device includes a plurality of adsorption columns, and an online mid-infrared spectrum detection system can be arranged on the inlet and outlet pipelines of each adsorption column.

[0018] The inlet pipe and outlet pipe for entering the sample pool are led out before and after the regulating valve with pressure difference in the material pipeline respectively; the pressure in the sample pool is adjusted below 69 bar by the valve, and the temperature of the material entering the sample pool is not higher than 200℃.

[0019] The spectrum is scanned by the optical fiber probe and processed by the instrument software workstation to obtain the peak-to-peak height of the spectrum at the characteristic wavelength.

[0020] Preferably, the feed to the adsorption device is derived from Fischer-Tropsch oil.

[0021] The infrared spectrometer detection steps of the present invention are:

[0022] (1) Calibration model establishment

[0023] Various Fischer-Tropsch synthetic oil samples were selected and the contents of olefins, alkanes and alkynes were determined by gas chromatography. Then, each sample was scanned by mid-infrared spectroscopy through a sample cell, and the C=C bond in the range of 3100-3010 cm was selected. -1 It is the characteristic spectral region; CC bond is at 2975~2800cm -1 Characteristic spectral region; C≡C bond is between 3300 and 2150 cm -1 The response values ​​of the above characteristic spectral regions are correlated with the contents of olefins, alkanes and alkynes determined by gas chromatography, and calibration models are established respectively by the least square method of chemometrics;

[0024] (2) Determination of unknown sample content

[0025] Under the same test conditions as those used to establish the calibration model, the mid-infrared spectrum of the unknown sample was scanned, with the wavelengths between 3100 and 3010 cm -1 、2975~2800cm -1 、3300~2150cm -1 The response values ​​of the spectral regions are substituted into the corresponding calibration models to obtain the contents of olefins, alkanes and alkynes in the unknown samples.

[0026] Preferably, the steps of establishing the calibration model using the least squares method of chemometrics are as follows:

[0027] (1) Assume that the peak height y of the spectrum of olefins (or alkanes or alkynes) at the characteristic wavelength and the concentration value x of the olefins (or alkanes or alkynes) have the following relationship: y = ax + b, where a is the coefficient and b is the intercept.

[0028] (2) There is a corresponding relationship for each set of data (xi, yi).

[0029] (3) Error e=yi-(axi+b)

[0030] (4) When The fitting degree is the highest when is the smallest, that is minimum, S represents the standard deviation (5) calculate the first-order partial derivative

[0031]

[0032]

[0033] (6) Let the above two equations be equal to 0, and we have

[0034] (7) Finally, we can get

[0035]

[0036]

[0037] (8) Substitute the x and y values ​​of each sample to obtain the a and b values, and then derive the linear relationship equation.

[0038] The adsorption device of the present invention is preferably a simulated moving bed device, and preferably has the following structure:

[0039] The simulated moving bed equipment includes an adsorption bed, a raw material feeding system, a desorbent feeding system, a circulation system, a liquid extraction system, a residual liquid extraction system, a programmable valve group and an automatic control system; wherein the adsorption bed includes a plurality of adsorption columns, which are divided into an adsorption zone, a purification zone and a desorption zone;

[0040] The upper end of each adsorption column is provided with a raw material feed valve, a desorbent feed valve, and a circulating liquid feed valve;

[0041] The lower end of each adsorption column is provided with a residual liquid discharge valve and an extracted liquid discharge valve;

[0042] A one-way valve is arranged between two adjacent adsorption columns;

[0043] The raw material feeding system is connected to the raw material feeding valve of each adsorption column;

[0044] The desorbent feed system is connected to the desorbent feed valve of each adsorption column;

[0045] The circulation system includes a circulation pump, and the circulation system is connected to the circulation liquid feed valve of each adsorption column through the circulation pump;

[0046] The extracted liquid system is connected to the extracted liquid discharge valve of each adsorption column;

[0047] The raffinate extraction system is connected to the raffinate extraction valve of each adsorption column;

[0048] All valves form a program-controlled valve group, which is connected to an automatic control system. The automatic control system can control the opening and closing status of each valve in the program-controlled valve group.

[0049] Preferably, the number of the adsorption columns is 3 to 100.

[0050] Preferably, the number of the adsorption columns is 8*N, wherein N is an integer greater than or equal to 1.

[0051] Preferably, the raw material feeding system comprises a raw material pump and a raw material heater located downstream of the raw material pump, and the outlet pipeline of the raw material heater is connected to the adsorption column;

[0052] The desorbent feeding system comprises a desorbent pump and a desorbent heater located downstream of the desorbent pump, and an outlet pipeline of the desorbent heater is connected to the adsorption column;

[0053] The extracted liquid system includes an extracted liquid pump connected to an extracted liquid pipeline of the adsorption bed;

[0054] The residual liquid extraction system comprises a residual liquid extraction pump, and the residual liquid extraction pump is connected to the residual liquid extraction pipeline of the adsorption bed;

[0055] The feed inlet of the circulation pump of the circulation system is connected to the extraction liquid pipeline of the adsorption bed.

[0056] Preferably, the valve types in the program-controlled valve group are independently selected from one of ball valve, needle valve, stop valve and butterfly valve. Preferably, the actuator is pneumatic or electric.

[0057] Preferably, the relative position of the circulating pump in the area remains unchanged.

[0058] Preferably, the volumes of the connecting pipelines between each adsorption column are the same.

[0059] Preferably, the volume of the pipeline connecting each adsorption column to the circulation pump is the same.

[0060] Preferably, it is characterized in that the adsorption zone also includes a buffer zone, that is, the adsorption bed is divided into an adsorption zone, a purification zone, a desorption zone and a buffer zone.

[0061] The high-efficiency simulated moving bed process using the above-mentioned high-efficiency simulated moving bed equipment is:

[0062] A high-efficiency simulated moving bed process using the high-efficiency simulated moving bed equipment controls valve switching to change the position of each material input and output, thereby realizing simulated movement of an adsorption zone, a purification zone, and a desorption zone.

[0063] Preferably, the valve switching is controlled to change the position of each material input and output, thereby realizing the simulated movement of the adsorption zone, purification zone, desorption zone and buffer zone.

[0064] Preferably, the number of adsorption columns is 8, and the high-efficiency simulated moving bed process is specifically:

[0065] 0-t time sequence, open the one-way valve A1 of adsorption column 1, the desorbent feed valve A2, the desorbent feed valve B2 of adsorption column 2, the extracted liquid discharge valve B6, the circulating liquid feed valve C4 of adsorption column 3, the one-way valve D1 of adsorption column 4, the one-way valve E1 of adsorption column 5, the raw material feed valve E3, the one-way valve F1 of adsorption column 6, the residual liquid discharge valve F5, the one-way valve G1 of adsorption column 7, the one-way valve H1 of adsorption column 8, and the remaining valves are closed;

[0066] At this time, the adsorption area is adsorption column 5 and adsorption column 6, the raw material enters adsorption column 5 and adsorption column 6, the target product components are adsorbed, and the non-target components flow out from the outlet;

[0067] The purification area is adsorption column 3 and adsorption column 4. The circulating pump drives the circulating liquid into adsorption column 3 and adsorption column 4 to purify the target product components adsorbed in the previous cycle.

[0068] The desorption zone is adsorption column 1 and adsorption column 2. The desorbent pump drives the desorbent and part of the desorbent from the buffer zone into adsorption column 1 and adsorption column 2. The target product components purified in the previous cycle are eluted and extracted from the system to achieve the purpose of adsorption separation.

[0069] The buffer zone is composed of adsorption column 7 and adsorption column 8. Most of the target product components in the raw material have been adsorbed in the adsorption zone, and the remaining large amount of non-target components and a small amount of target component mixed liquid enter the buffer zone, waiting for the next cycle.

[0070] The valve switching is controlled to change the position of the material inlet and outlet in the t-2t, 2t-3t, and 3t-4t time sequence, realizing the simulated movement of the adsorption zone, purification zone, desorption zone, and buffer zone.

[0071] Beneficial Effects

[0072] (1) The online mid-infrared spectrum detection system of the present invention is more convenient than offline detection and the measurement result accuracy is reliable; the operating conditions of the adsorption process are adjusted in real time according to the online detection results, so as to achieve rapid response of process operation and improve production efficiency, product quality and product qualification rate. The mid-infrared spectrum range is selected, which has strong anti-interference ability and high measurement accuracy, and well realizes product quality control in industrial mass production, reduces costs and is easy to operate.

[0073] (2) By setting up an online mid-infrared spectroscopy detection system in the adsorption device, the adsorption separation process operation can be monitored in real time. Furthermore, an online mid-infrared spectroscopy detection system is set up on the inlet and outlet pipelines of each adsorption column, which can improve the monitoring accuracy, realize real-time monitoring of the working status and performance of each adsorption column, and then adjust the operating conditions of the corresponding adsorption column, maximize production efficiency, reduce costs and energy consumption, and accurately indicate the time when the adsorption column needs to be replaced.

[0074] (3) The branch sample pool is combined with the fiber optic probe measurement to reduce the sample measurement pre-treatment process, reduce the cumbersome detection process, and realize online detection. The detection method is easy to implement and has wide environmental conditions. It is suitable for the detection of olefins, alkanes, and alkynes in liquid hydrocarbons at -80℃ to 200℃ and a pressure of 69 bar. The detection is non-destructive to the sample and does not require the addition of other auxiliary reagents. At the same time, it reduces the difficulty of detection, increases the detection frequency, and provides timely data guidance for process operations. The detection carbon number is C4-C40, which has a wider range.

[0075] (4) The present invention uses a programmable valve group to replace the traditional multi-channel rotary valve to control the cycle conversion of the simulated moving bed, which reduces the equipment cost; the programmable valve group can be flexibly cut out according to maintenance requirements, which is convenient for equipment maintenance; each adsorption column can be cut out for maintenance, and the system can be cut in after the adsorbent is replaced, which greatly improves the long-term operation capacity of the device. At the same time, the volume of each pipeline connected to the adsorption column in the present invention is the same, and the relative position of the circulating pump in the area remains unchanged, so the flow rate of the circulating pump remains unchanged, the pressure fluctuation is small, and the control is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Figure 1 Schematic diagram of sample detection of the present invention

[0077] Figure 2 It is a schematic diagram of a high-efficiency simulated moving bed device of the present invention. DETAILED DESCRIPTION

[0078] The sample detection schematic diagram of the present invention is as follows Figure 1 A branch with a test sample pool is set on the material pipeline, and the material in the sample pool is tested using an online mid-infrared spectrometer.

[0079] The detection steps are as follows:

[0080] (1) Calibration model establishment

[0081] The contents of olefins, alkanes and alkynes in 100 Fischer-Tropsch synthetic oil samples were determined by gas chromatography. Each sample was then scanned by mid-infrared spectroscopy through a sample cell, and the C=C bond in the range of 3100-3010 cm -1 It is the characteristic spectral region; CC bond is at 2975~2800cm -1 Characteristic spectral region; C≡C bond is between 3300 and 2150 cm -1 The response values ​​of the above characteristic spectral regions are correlated with the contents of olefins, alkanes and alkynes determined by gas chromatography, and calibration models are established respectively by the least square method of chemometrics;

[0082] The above-mentioned sample enters the sample pool through the inlet pipe after passing through the material pipeline. The inlet pipe and outlet pipe entering the test sample pool are respectively led out before and after the regulating valve with pressure difference in the material pipeline. The pressure in the sample pool is adjusted below 69 bar by the valve, and the temperature of the material entering the sample pool is not higher than 200°C. The sample pool is a branch flow sample pool, and the infrared spectrometer adopts fiber optic probe type measurement.

[0083] The gas chromatograph used was Agilent 7820 gas chromatograph, PONA column, split / splitless inlet, and PONA column.

[0084] The mid-infrared spectrometer used was Mettler ReactIR15, with a spectral range of 4000-650 cm -1 , resolution 4cm -1 .

[0085] The spectrum is scanned by the optical fiber probe and processed by the instrument software workstation to obtain the peak-to-peak height of the spectrum at the characteristic wavelength.

[0086] (2) Content determination

[0087] The mid-infrared spectrum of the sample was scanned under the same test conditions as those used to establish the calibration model, with the wavelengths between 3100 and 3010 cm -1 、2975~2800cm -1 、3300~2150cm -1 The response values ​​of the spectral regions are substituted into the corresponding calibration models to obtain the contents of olefins, alkanes and alkynes in the samples. By comparing the gas chromatography test results and the online mid-infrared spectroscopy test results of the samples, it can be seen that the online mid-infrared spectroscopy and gas chromatography test results are basically consistent, and the maximum deviation of the infrared spectroscopy measurement results compared with the gas chromatography measurement results is only about ±2%.

[0088] During the adsorption and separation process of the adsorption device of the present invention, the adsorption and separation process can be monitored in real time by an online mid-infrared spectrum detection system provided in the adsorption device, so as to adjust the operating conditions or repair and replace the adsorption column.

[0089] Figure 2 In the figure, an adsorption bed composed of 8 adsorption columns is taken as an example to specifically illustrate the structure of the simulated moving bed device of the present invention.

[0090] A high-efficiency simulated moving bed device, comprising an adsorption bed, a raw material feeding system, a desorbent feeding system, a circulation system, an extraction liquid system, a residual liquid extraction system, a programmable valve group and an automatic control system; wherein the adsorption bed comprises a plurality of adsorption columns, which are divided into an adsorption zone, a purification zone, a desorption zone and a buffer zone (it should be noted that the present embodiment adopts an adsorption bed comprising an adsorption zone, a purification zone, a desorption zone and a buffer zone, but the buffer zone is not necessarily selected for the present invention and is optional);

[0091] The upper ends of the adsorption columns 1-8 are respectively provided with raw material feed valves A3, B3, C3, D3, E3, F3, G3, H3, desorbent feed valves A2, B2, C2, D2, E2, F2, G2, H2, and circulating liquid feed valves A4, B4, C4, D4, E4, F4, G4, H4;

[0092] The lower ends of the adsorption columns 1-8 are respectively provided with residual liquid discharge valves A5, B5, C5, D5, E5, F5, G5, H5, and extracted liquid discharge valves A6, B6, C6, D6, E6, F6, G6, H6;

[0093] One-way valves A1, B1, C1, D1, E1, F1, G1, and H1 are arranged between two adjacent adsorption columns;

[0094] The raw material feeding system is connected to the raw material feeding valves A3, B3, C3, D3, E3, F3, G3, and H3 of each adsorption column;

[0095] The desorbent feed system is connected to the desorbent feed valves A2, B2, C2, D2, E2, F2, G2, and H2 of each adsorption column;

[0096] The circulation system includes a circulation pump, and the circulation liquid feeding system is connected to the circulation liquid feeding valves A4, B4, C4, D4, E4, F4, G4, and H4 of each adsorption column through the circulation pump;

[0097] The extracted liquid system is connected to the extracted liquid discharge valves A6, B6, C6, D6, E6, F6, G6, and H6 of each adsorption column;

[0098] The raffinate extraction system is connected to the raffinate extraction valves A5, B5, C5, D5, E5, F5, G5, and H5 of each adsorption column;

[0099] In this embodiment, the relative position of the circulating pump in the area remains unchanged, so the flow rate of the circulating pump remains unchanged, the volume of the connecting pipelines between each adsorption column is the same, and the volume of the pipeline connecting each adsorption column to the circulating pump is the same. Therefore, the flow rate of the circulating pump in this embodiment remains unchanged, the pressure fluctuation is small, and the control is simple.

[0100] In this embodiment, all valves form a program-controlled valve group, which is connected to an automatic control system. The automatic control system can control the opening and closing state of each valve in the program-controlled valve group.

[0101] As an improvement of the present embodiment, optionally, the raw material feeding system includes a raw material pump and a raw material heater located downstream of the raw material pump, and the raw material heater outlet pipeline is connected to the adsorption column; the raw material pump can provide feeding power for the raw material feed, and the raw material heater can heat the raw material to a suitable temperature to improve the adsorption activity, and the specific pumping pressure and heating temperature are determined according to the characteristics of the material separation system.

[0102] As an improvement of the present embodiment, optionally, the desorbent feed system includes a desorbent pump and a desorbent heater located downstream of the desorbent pump, and the outlet pipeline of the desorbent heater is connected to the adsorption column; the desorbent pump can provide feeding power for the desorbent feed, and the desorbent heater can heat the desorbent to a suitable temperature to improve the desorption capacity, and the specific pumping pressure and heating temperature are determined according to the characteristics of the material separation system.

[0103] As an improvement of this embodiment, optionally, the extracted liquid system includes an extracted liquid pump, which is connected to the extracted liquid pipeline of the adsorption bed and provides power for extracting the extracted liquid.

[0104] As an improvement of this embodiment, the residual liquid extraction system may optionally include a residual liquid extraction pump connected to a residual liquid extraction pipeline of the adsorption bed, and the residual liquid extraction pump provides power for extracting the residual liquid.

[0105] As an improvement of this embodiment, optionally, the feed port of the circulation pump of the circulation system is connected to the extraction liquid pipeline of the adsorption bed to circulate the extraction liquid.

[0106] As an improvement of this embodiment, optionally,

[0107] The valve types in the program-controlled valve group are independently selected as one of ball valves, needle valves, stop valves, and butterfly valves; that is, the 56 valves in this embodiment are independently selected as one of ball valves, needle valves, stop valves, and butterfly valves, and there is no interference between them. The valve actuator is pneumatic or electric.

[0108] As an improvement of this embodiment, the relative position of the circulation pump in the area remains unchanged, so the flow rate of the circulation pump remains unchanged, the volume of the connecting pipelines between each adsorption column is the same, and the volume of the pipeline connecting each adsorption column to the circulation pump is the same. Therefore, the flow rate of the circulation pump of this embodiment remains unchanged, the pressure fluctuation is small, and the control is simple.

Claims

1. An adsorption device capable of online monitoring, characterized in that: The adsorption equipment includes an online mid-infrared spectrum detection system. A branch line with a test sample pool is set on the material pipeline that needs to be monitored online, and the material in the sample pool is tested using an online mid-infrared spectrometer; The mid-infrared spectrum detection system is arranged on the inlet and outlet pipelines of the adsorption equipment; The adsorption equipment is a simulated moving bed equipment; the simulated moving bed equipment includes an adsorption bed, a raw material feeding system, a desorbent feeding system, a circulation system, a liquid extraction system, a residual liquid extraction system, a programmable valve group and an automatic control system; wherein the adsorption bed includes a plurality of adsorption columns, which are divided into an adsorption zone, a purification zone and a desorption zone; The upper end of each adsorption column is provided with a raw material feed valve, a desorbent feed valve, and a circulating liquid feed valve; The lower end of each adsorption column is provided with a residual liquid discharge valve and an extracted liquid discharge valve; A one-way valve is arranged between two adjacent adsorption columns; The raw material feeding system is connected to the raw material feeding valve of each adsorption column; The desorbent feed system is connected to the desorbent feed valve of each adsorption column; The circulation system includes a circulation pump, and the circulation system is connected to the circulation liquid feed valve of each adsorption column through the circulation pump; The extracted liquid system is connected to the extracted liquid discharge valve of each adsorption column; The raffinate extraction system is connected to the raffinate extraction valve of each adsorption column; All valves form a program-controlled valve group, which is connected to an automatic control system. The automatic control system can control the opening and closing status of each valve in the program-controlled valve group. Before and after the regulating valve with pressure difference in the material pipeline, an inlet pipe and an outlet pipe entering the sample pool are led out respectively.

2. The adsorption device capable of online monitoring according to claim 1, characterized in that: The mid-infrared spectrometer uses a fiber optic probe for measurement, with a spectral range of 4000-650cm -1 , resolution 4cm -1 .

3. The adsorption device capable of online monitoring according to claim 1, characterized in that: The adsorption equipment comprises a plurality of adsorption columns, and an online mid-infrared spectrum detection system is arranged on the inlet and outlet pipelines of each adsorption column.

4. The adsorption device capable of online monitoring according to claim 1, characterized in that: The pressure in the sample cell is adjusted to below 69 bar by means of a valve, and the temperature of the material entering the sample cell is kept below 200°C.

5. The online monitorable adsorption device according to claim 2, characterized in that: The spectrum is scanned by the optical fiber probe and processed by the instrument software workstation to obtain the peak-to-peak height of the spectrum at the characteristic wavelength.

6. The online monitorable adsorption device according to any one of claims 1 to 5, characterized in that: The detection steps of mid-infrared spectrometer are as follows: (1) Calibration model establishment Various Fischer-Tropsch synthetic oil samples were selected and the contents of olefins, alkanes and alkynes were determined by gas chromatography. Then, each sample was scanned by mid-infrared spectroscopy through a sample cell, and the C=C bond in the range of 3100-3010 cm was selected. -1 It is the characteristic spectral region; CC bond is at 2975~2800cm -1 Characteristic spectral region; C≡C bond is between 3300 and 2150 cm -1 The response values ​​of the above characteristic spectral regions are correlated with the contents of olefins, alkanes and alkynes determined by gas chromatography, and calibration models are established respectively by the least square method of chemometrics; (2) Determination of unknown sample content Under the same test conditions as those used to establish the calibration model, the mid-infrared spectrum of the unknown sample was scanned, with the wavelengths between 3100 and 3010 cm -1 、2975~2800cm -1 、3300~2150cm -1 The response values ​​of the spectral regions are substituted into the corresponding calibration models to obtain the contents of olefins, alkanes and alkynes in the unknown samples.

7. The adsorption device capable of online monitoring according to claim 1, characterized in that: The number of the adsorption columns is 3 to 100.

Images