Chemical wastewater VOC content detection device

Abstract

This invention discloses a VOC content detection device for chemical wastewater, comprising a sampling shell, a sampling container, and a rotating disk. A tube is located in the center of the rotating disk. A driving disk is movably mounted at the upper end of the tube, with its upper end extending upward through the sampling shell and movably fitted with an adjusting ring. Two extraction mechanisms are slidably mounted on the rotating disk within the tube. A piston column, driven and connected to the outer wall of the tube, is slidably mounted inside the sampling shell, with its upper end extending outward through the sampling shell. A connecting valve is mounted on the driving disk, connected to a gas chromatograph-mass spectrometer. A first magnetic element is located at the bottom of the connecting valve. A second magnetic element is located at the top of each extraction mechanism. The extraction mechanisms are driven and connected to the driving disk. When the driving disk slides, it causes one of the extraction mechanisms to move relative to the connecting valve. This device allows for direct thermal desorption-gas chromatography detection of VOCs on the two extraction strips, thereby improving the accuracy of the detection results. It is simple to operate and helps avoid secondary pollution problems.

Description

Technical Field

[0001] This invention relates to the field of VOC content detection technology, and in particular to a device for detecting VOC content in chemical wastewater. Background Technology

[0002] In the field of environmental protection and pollution control, the content of volatile organic compounds (VOCs) in chemical wastewater is an important detection indicator. Traditional VOC detection techniques include direct injection gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS), liquid chromatography (LC), and Fourier transform infrared spectroscopy (FTIR).

[0003] However, these detection technologies are complex to sample processing: they require sample pretreatment, such as solvent extraction and solid-phase microextraction, which are often time-consuming and may introduce contamination, affecting the accuracy of the test results. Furthermore, some require the use of organic solvents, which not only increases operational complexity but may also lead to secondary contamination. Summary of the Invention

[0004] The purpose of this invention is to overcome the above-mentioned shortcomings and provide a VOC content detection device for chemical wastewater, which can directly perform thermal desorption-gas chromatography detection on VOCs on two extraction strips, thereby improving the accuracy of the detection results, simplifying operation, and helping to avoid secondary pollution problems.

[0005] To achieve the above objectives, the specific solution of the present invention is as follows:

[0006] A VOC content detection device for chemical wastewater includes a sampling shell, a sampling container at the lower end of the sampling shell, a rotating disk at the top of the sampling container, and a tube in the middle of the rotating disk; a driving disk is movably provided at the upper end of the tube, the upper end of the driving disk extends upward through the sampling shell and is movably fitted with an adjusting ring for sliding the driving disk relative to the tube; the rotating disk is slidably provided with two extraction mechanisms communicating with the sampling container in the tube.

[0007] The sampling housing has a piston rod that is slidably connected to the outer wall of the tube and is driven by the outer wall of the tube. The upper end of the piston rod extends outward through the sampling housing. When the piston rod moves up and down relative to the sampling housing, it can drive the rotating disk to rotate.

[0008] The drive disc is equipped with a connecting valve, which is connected to the gas chromatograph-mass spectrometer through the drive disc; the bottom of the connecting valve is equipped with a first magnetic component; the top of the extraction mechanism is equipped with a second magnetic component; the extraction mechanism is connected to the drive disc in a transmission manner, and when the drive disc slides, the drive disc causes one of the extraction mechanisms to move relative to the bottom of the connecting valve.

[0009] Optionally, a sampling chamber is formed between the sampling container and the rotating disk; a first cavity communicating with the sampling chamber is formed between the sampling shell, the rotating disk, the tube, and the piston rod; a second cavity is formed between the sampling shell, the piston rod, the tube, and the drive disk; a third cavity communicating with the second cavity is formed between the drive disk, the tube, and the rotating disk; and a conductive terminal is provided on the rotating disk directly below the connecting valve.

[0010] The extraction mechanism includes an extraction tube located in the third chamber, a heating rod disposed inside the extraction tube, and an extraction strip slidably sleeved on the outer wall of the heating rod; the upper end of the heating rod is connected to the upper end of the extraction tube; a first spring is provided between the upper end of the extraction strip and the upper end of the extraction tube; the extraction strip is sealed to the inner wall of the extraction tube, so that the upper end of the extraction tube is connected to the third chamber and the lower end of the extraction tube is connected to the sampling chamber; the first spring causes the extraction strip to be housed inside the extraction tube; a first magnetic element is disposed on the upper end face of the extraction tube.

[0011] Optionally, the inner wall of the extraction tube is provided with a first track, which includes a first vertical groove and a first spiral groove. The upper end of the first spiral groove is connected to the lower end of the first vertical groove, and the upper end of the first vertical groove is provided with a locking groove that smoothly transitions to the first vertical groove. The extraction strip is provided with a first pin, which is movably embedded in the first track. A sealing ring is sleeved on the outer wall of the first pin. A thermal expansion body is embedded in the first pin, which can protrude outward from the first pin when its temperature reaches the deformation temperature threshold.

[0012] Optionally, the bottom surface of the drive plate is provided with a first arc groove, and the groove wall of the first arc groove is provided with two rotationally symmetrical second tracks, the second tracks including a second vertical groove and a second spiral groove; the outer wall of the extraction tube is provided with a second pin, which is movably embedded in the corresponding second track.

[0013] Optionally, the inner wall of the adjusting ring is provided with a third track, and the center of the top surface of the drive disk is provided with a central shaft that protrudes out of the sampling housing. The adjusting ring is movably sleeved on the outer wall of the central shaft, and the outer wall of the central shaft is provided with a third pin that is movably embedded in the third track.

[0014] The third track includes a first horizontal groove, a third spiral groove extending downwards, and a fourth spiral groove extending upwards; the two ends of the first horizontal groove are respectively connected to the upper end of the third spiral groove and the lower end of the fourth spiral groove; initially, the third pin is located in the first horizontal groove.

[0015] Optionally, the lower end of the third spiral groove is connected to a second horizontal groove; the upper end of the fourth spiral groove is connected to a third horizontal groove.

[0016] Optionally, both the drive disc and the central shaft are equipped with air intake channels. The lower end of the air intake channel is connected to the connecting valve via a hose, and the upper end of the air intake channel is connected to the gas chromatograph-mass spectrometer.

[0017] Optionally, the drive disc has a mounting hole that communicates with the first arc groove; the connecting valve includes a valve body that is movably inserted into the mounting hole and a second spring that is sleeved on the outer wall of the valve body; the two ends of the second spring abut against the upper end face of the drive disc and the upper end of the valve body, respectively; the valve body communicates with the third cavity.

[0018] Optionally, the rotating disk has a second arc groove inside the tube, and the lower end of the extraction tube is slidably connected in the second arc groove; the conductive terminal is located in the second arc groove and between the two extraction tubes.

[0019] Optionally, the inner wall of the piston rod is provided with a fourth retaining pin, and the outer wall of the tube is provided with a fifth spiral groove, with the fourth retaining pin being movably embedded in the fifth spiral groove.

[0020] The beneficial effects of this invention are as follows: By setting up a piston column, a rotating disk, a driving disk, and two extraction mechanisms on the rotating disk, the piston column moves up and down, and the gas pressure is used to simultaneously complete the classification extraction of the two extraction mechanisms. Then, by adjusting the ring, the two extraction mechanisms are respectively aligned with the positions of the connecting valve and the conductive terminal, so that the VOCs on the two extraction strips can be directly detected by thermal desorption-gas chromatography, thereby improving the accuracy of the detection results, simplifying the operation, and helping to avoid secondary pollution problems. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the present invention;

[0022] Figure 2 This is a cross-sectional schematic diagram of the present invention;

[0023] Figure 3 This is a cross-sectional schematic diagram from another perspective of the present invention;

[0024] Figure 4 This is a partial structural schematic diagram of the present invention;

[0025] Figure 5 This is an exploded schematic diagram of the extraction mechanism of the present invention;

[0026] Figure 6 This is a cross-sectional schematic diagram of the extraction mechanism of the present invention;

[0027] Figure 7 yes Figure 6 A magnified view of a portion of point A in the middle;

[0028] Figure 8 This is a schematic diagram of the drive disk of the present invention;

[0029] Figure 9 This is a schematic diagram of the structure of the adjusting ring of the present invention;

[0030] Figure 10 This is a schematic diagram of the structure of the connecting valve of the present invention;

[0031] Figure 11 This is a schematic diagram of the rotating disk of the present invention;

[0032] Figure 12 This is a schematic diagram of the piston column structure of the present invention;

[0033] Explanation of reference numerals in the attached drawings: 1. Sampling housing; 2. Sampling container; 21. One-way valve; 3. Rotating disk; 31. Tube body; 32. Second arc groove; 33. Conductive terminal; 34. Fifth spiral groove; 4. Drive disk; 41. Central shaft; 411. Third pin; 42. First arc groove; 43. Second vertical groove; 44. Second spiral groove; 45. Gas duct; 46. Mounting hole; 5. Adjusting ring; 51. First horizontal groove; 52. Third spiral groove; 53. Fourth spiral groove; 54. Second horizontal groove; 55. Third horizontal groove; 61. Extraction tube; 611. First vertical groove 612. First spiral groove; 613. Locking groove; 614. Second pin; 62. Heating rod; 63. Extraction strip; 631. First pin; 632. Sealing ring; 633. Thermal expansion body; 64. Second magnetic component; 65. First spring; 7. Piston column; 71. First ring; 72. Second ring; 73. Column; 74. Fourth locking pin; 8. Connecting valve; 81. Valve body; 82. Second spring; 83. First magnetic component; 84. Flexible tube; 9. Gas chromatograph-mass spectrometer; 10. Sampling chamber; 20. First chamber; 30. Second chamber; 40. Third chamber. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but this is not to limit the scope of the invention to this.

[0035] like Figures 1 to 12 As shown in the figure, the chemical wastewater VOC content detection device described in this embodiment includes a sampling shell 1, which is cylindrical, with a closed end at the upper end and an open end at the lower end.

[0036] The lower end of the sampling housing 1 is provided with a sampling container 2. The sampling container 2 is cylindrical so that it can be installed inside the sampling housing 1. The upper end of the sampling container 2 is an open end and the lower end of the sampling container 2 is a closed end. The closed end of the sampling container 2 is provided with a one-way valve 21. There are two one-way valves 21, which are spaced apart. When the air pressure inside the sampling container 2 decreases, the one-way valve 21 can open to allow the sample liquid to enter the sampling container 2.

[0037] A rotating disk 3 is rotatably mounted on the top of the sampling container 2. The outer peripheral wall of the rotating disk 3 is sealed to the inner peripheral wall of the sampling shell 1. A tube 31 protrudes from the middle of the rotating disk 3. A through hole is provided on the rotating disk 3 so that the sampling container 2 can communicate with the upper part of the sampling shell 1. A drive disk 4 is movably mounted at the upper end of the tube 31.

[0038] The upper end of the drive disk 4 extends upward through the sampling housing 1 and is movably fitted with an adjustment ring 5 for sliding the drive disk 4 relative to the tube body 31. The user uses the adjustment ring 5 to make the drive disk 4 slide up and down relative to the tube body 31. The rotating disk 3 is slidably provided with two extraction mechanisms that are connected to the sampling container 2 within the tube body 31.

[0039] The sampling housing 1 has a piston rod 7 that is slidably connected to the outer wall of the tube 31 inside the tube body 31; the upper end of the piston rod 7 extends outward from the sampling housing 1.

[0040] The piston column 7 has a first ring 71, a second ring 72, and two columns 73 connected between the first ring 71 and the second ring 72. The first ring 71 is slidably sleeved on the outer peripheral wall of the tube 31. The two columns 73 extend out after passing through the closed end of the sampling housing 1. The second ring 72 is fixedly connected to the upper ends of the two columns 73. The user operates the piston column 7 through the second ring 72 to move the piston column 7 up and down. When the piston column 7 moves up and down relative to the sampling housing 1, it can drive the rotating disk 3 to rotate.

[0041] The drive disk 4 is equipped with a connecting valve 8, which is connected to the gas chromatograph-mass spectrometer 9 via the drive disk 4. A first magnetic element 83 is located at the bottom of the connecting valve 8; a second magnetic element 64 is located at the top of the extraction mechanism. The first magnetic element 83 and the second magnetic element 64 have opposite magnetic properties. The extraction mechanism is connected to the drive disk 4 via a transmission mechanism. When the drive disk 4 slides, it causes one of the extraction mechanisms to move relative to the connecting valve 8 and move directly below it. When the extraction mechanism moves directly below the connecting valve 8, the first magnetic element 83 and the second magnetic element 64 are attracted to each other, allowing the extraction mechanism to connect to the gas chromatograph-mass spectrometer 9 via the connecting valve 8. Both the first magnetic element 83 and the second magnetic element 64 are permanent magnets.

[0042] Specifically, such as Figure 2 and Figure 3 As shown, a sampling chamber 10 is formed between the sampling container 2 and the rotating disk 3. A first cavity 20, which communicates with the sampling chamber 10, is formed between the sampling housing 1, the rotating disk 3, the tube 31, and the piston column 7. The first cavity 20 is connected to the sampling chamber 10 through a connecting hole. A second cavity 30 is formed between the sampling housing 1, the piston column 7, the tube 31, and the drive disk 4. A third cavity 40, which communicates with the second cavity 30, is formed between the drive disk 4, the tube 31, and the rotating disk 3. A conductive terminal 33 is provided on the rotating disk 3 directly below the connecting valve 8.

[0043] like Figure 2 , Figure 3 , Figures 5 to 7 As shown, the extraction mechanism includes an extraction tube 61 located within the third chamber 40, a heating rod 62 disposed within the extraction tube 61, and an extraction strip 63 slidably sleeved on the outer wall of the heating rod 62. The extraction strip 63 is made of fiber material, and the appropriate fiber material is selected according to the VOC substance to be extracted. The extraction strip 63 includes a disc portion and a spiral portion. The disc portion is slidably and sealed within the extraction tube 61, and the spiral portion is connected to the disc portion. The spiral portion extends spirally around the axis of the heating rod 62. The upper end of the heating rod 62 is connected to the upper end of the extraction tube 61 for heating. The lower end face of the rod 62 is flush with the lower end face of the extraction tube 61; a first spring 65 is provided between the upper end of the extraction strip 63 and the upper end of the extraction tube 61; the extraction strip 63 is sealed to the inner wall of the extraction tube 61, so that the upper end of the extraction tube 61 is connected to the third cavity 40 and the lower end of the extraction tube 61 is connected to the sampling cavity 10; the first spring 65 causes the extraction strip 63 to be housed in the extraction tube 61; a first magnetic element 83 is provided on the upper end face of the extraction tube 61; when the piston column 7 moves upward, the extraction strip 63 overcomes the elastic force of the first spring 65 under the action of air pressure and extends downward into the sampling cavity 10.

[0044] In this embodiment of the chemical wastewater VOC content detection device, during actual use, one extraction strip 63 is coated with a polydimethylsiloxane (PDMS) coating, and the other extraction strip 63 is coated with a polyacrylate (PA) coating, used for adsorbing non-polar compounds and polar compounds respectively; the piston column 7 is initially at the bottom dead center position. By pulling the piston column 7 upward, the effective volume of the first chamber 20 and the sampling chamber 10 increases, the one-way valve 21 opens, and the sample liquid enters the sampling chamber 10 through the one-way valve 21 until the piston column 7... As the piston column 7 moves upward to the upper stop position, it drives the rotating disk 3 to rotate. The rotating disk 3 drives the driving disk 4 and the extraction mechanism to rotate synchronously. The driving disk 4 drives the adjusting ring 5 to rotate. At the same time, as the volume of the second chamber 30 gradually decreases, the gas in the second chamber 30 enters the third chamber 40. The pressure in the third chamber 40 increases, causing the two extraction strips 63 to overcome the elastic force of the first spring 65 under the action of air pressure, penetrate the rotating disk 3 and extend into the sampling chamber 10. At this time, the extraction strips 63 are inserted into the sample liquid for extraction.

[0045] Then the piston column 7 is pressed down. At this time, the rotating disk 3 rotates in the opposite direction. The effective volume of the first chamber 20 and the sampling chamber 10 decreases. The one-way valve 21 is closed. The effective volume of the second chamber 30 increases. The pressure of the third chamber 40 decreases. At this time, the extraction strip 63 is retracted into the extraction tube 61 under the combined action of air pressure and the elastic force of the first spring 65, thus completing the extraction process.

[0046] Then, by rotating the adjusting ring 5, the driving disk 4 slides relative to the tube body 31, causing one of the extraction mechanisms to move directly below the connecting valve 8. At this time, the corresponding second magnetic component 64 cooperates with the first magnetic component 83, so that the connecting valve 8 is sealed and connected to the extraction tube 61. The heating rod 62 is electrically connected to the conductive terminal 33, so that the heating rod 62 is energized and works to heat the VOC on the extraction strip 63. After heating, the VOC gas evaporates and enters the gas chromatograph 9 through the connecting valve 8. The gas chromatograph 9 detects the VOC gas, thus completing the thermal desorption-gas chromatography (TD-GC) detection of the VOC on the extraction strip 63 of the extraction mechanism.

[0047] Then, the adjusting ring 5 is rotated in the opposite direction, causing the drive disk 4 to slide in the opposite direction. The drive disk 4 causes another extraction mechanism to move directly below the connecting valve 8. At this time, the corresponding second magnetic component 64 cooperates with the first magnetic component 83, so that the connecting valve 8 is sealed and connected to the extraction tube 61. The heating rod 62 is energized to heat the VOC on the extraction strip 63, thereby performing thermal desorption-gas chromatography (TD-GC) detection on the VOC on the extraction strip 63 of the other extraction mechanism.

[0048] This embodiment sets up a piston column 7, a rotating disk 3, a driving disk 4, and two extraction mechanisms on the rotating disk 3. By moving the piston column 7 up and down, the two extraction mechanisms can simultaneously perform classified extraction using air pressure. Then, by adjusting the ring 5, the two extraction mechanisms are aligned with the positions of the connecting valve 8 and the conductive terminal 33, respectively. This allows for direct thermal desorption-gas chromatography detection of VOCs on the two extraction strips 63, thereby improving the accuracy of the detection results, simplifying the operation, and helping to avoid secondary pollution problems.

[0049] like Figure 2 , Figures 5 to 7 As shown, in some embodiments of the chemical wastewater VOC content detection device of this embodiment, the inner wall of the extraction tube 61 is provided with a first track, the first track includes a first vertical groove 611 and a first spiral groove 612, the upper end of the first spiral groove 612 is connected to the lower end of the first vertical groove 611, and the upper end of the first vertical groove 611 is provided with a locking groove 613 that smoothly transitions to the first vertical groove 611; the extraction strip 63 is provided with a first pin 631, which is movably embedded in the first track; a sealing ring 632 is sleeved on the outer wall of the first pin 631; a thermal expansion body 633 is embedded in the first pin 631, the thermal expansion body 633 is a shape memory alloy, and the thermal expansion body 633 can protrude outward from the first pin 631 when its temperature reaches the deformation temperature threshold.

[0050] Specifically, initially, under the elastic force of the first spring 65, the first pin 631 is located in the locking groove 613; when the user pulls the piston column 7 upward, the extraction strip 63 moves downward under the action of air pressure, and the first pin 631 enters the first vertical groove 611 from the locking groove 613 and moves along the first vertical groove 611, and then enters the first spiral groove 612 from the first vertical groove 611, so that the extraction strip 63 rotates synchronously during the downward movement, thereby stirring the sample liquid in the sampling chamber 10 and improving the uniformity of extraction; when the piston column 7 moves upward, the extraction strip 63 moves upward and rotates synchronously, so that excess water on the surface of the extraction strip 63 is separated under centrifugal action, thus making the extraction more accurate;

[0051] When the first pin 631 returns to the locking groove 613, the extraction mechanism is moved to the position directly below the connecting valve 8 by adjusting the ring 5. At this time, the heating rod 62 is energized, so that the VOC gas on the extraction strip 63 enters the gas chromatograph-mass spectrometer 9 through the connecting valve 8 for detection. At the same time, the thermal expansion body 633 is heated and its temperature rises. When it reaches its deformation temperature threshold, the thermal expansion body 633 deforms and extends into the locking groove 613 and cooperates with the locking groove 613 to lock the extraction strip 63 in an unlockable manner, making the structure more reliable.

[0052] like Figure 5 , Figure 6 and Figure 8 As shown, in some embodiments of the chemical wastewater VOC content detection device of this embodiment, the bottom surface of the drive disk 4 is provided with a first arc groove 42, and the groove wall of the first arc groove 42 is provided with two rotationally symmetrical second tracks, including a second vertical groove 43 and a second spiral groove 44; the outer wall of the extraction tube 61 is provided with a second pin 614, which is movably embedded in the corresponding second track. Initially, the second pin 614 is located at the junction of the second vertical groove 43 and the second spiral groove 44.

[0053] Specifically, when the adjusting ring 5 is rotated, causing the drive disk 4 to move downward, the second pin 614 of one of the extraction tubes 61 moves along the corresponding second spiral groove 44, thereby allowing the extraction tube 61 to slide relative to the rotating disk 3 to directly below the connecting valve 8 through the engagement of the second pin 614 and the second spiral groove 44; due to the rotational symmetry of the two second tracks, the second pin 614 of the other extraction tube 61 moves along the corresponding second vertical groove 43, that is, the extraction tube 61 will not slide relative to the rotating disk 3; when the adjusting ring 5 is rotated in the opposite direction, causing the drive disk 4 to move upward, the second pin 614 of the other extraction tube 61 enters the corresponding second spiral groove 44, thereby allowing the other extraction tube 61 to slide directly below the connecting valve 8; in this way, the VOC gas on the two extraction strips 63 is detected respectively.

[0054] like Figure 8and Figure 9 As shown, in some embodiments of the chemical wastewater VOC content detection device of this embodiment, the inner wall of the adjusting ring 5 is provided with a third track, the center of the top surface of the drive disk 4 is provided with a central shaft 41 that protrudes out of the sampling housing 1, the adjusting ring 5 is movably sleeved on the outer wall of the central shaft 41, and the outer wall of the central shaft 41 is provided with a third pin 411 that protrudes out and is movably embedded in the third track.

[0055] The third track includes a first horizontal groove 51, a third spiral groove 52 extending downwards, and a fourth spiral groove 53 extending upwards; the two ends of the first horizontal groove 51 are respectively connected to the upper end of the third spiral groove 52 and the lower end of the fourth spiral groove 53; initially, the third pin 411 is located in the first horizontal groove 51.

[0056] Specifically, when the adjusting ring 5 is rotated, the third pin 411 moves along the first horizontal groove 51 and enters the fourth spiral groove 53 from the first horizontal groove 51. At this time, the third pin 411 cooperates with the fourth spiral groove 53, causing the drive disk 4 to move downward, thereby causing one of the extraction tubes 61 to move directly below the connecting valve 8. When the adjusting ring 5 is rotated in the opposite direction, the third pin 411 enters the third spiral groove 52 from the first horizontal groove 51, thereby causing the drive disk 4 to move upward, causing the other extraction tube 61 to move directly below the connecting valve 8, thereby completing the detection of VOC gas on the two extraction strips 63.

[0057] like Figure 9 As shown, in some embodiments of the chemical wastewater VOC content detection device of this embodiment, the lower end of the third spiral groove 52 is connected to the second horizontal groove 54; the upper end of the fourth spiral groove 53 is connected to the third horizontal groove 55. In this embodiment, by setting the third horizontal groove 55, when the third pin 411 moves along the fourth spiral groove 53, the third pin 411 can enter the third horizontal groove 55 from the fourth spiral groove 53, thereby keeping the drive disk 4 at its current upward height position; similarly, by setting the second horizontal groove 54, the drive disk 4 is kept at its current downward height position, so as to maintain the position of the extraction tube 61.

[0058] like Figure 2 , Figure 3 and Figure 8As shown, in some embodiments of the chemical wastewater VOC content detection device, both the drive disc 4 and the central shaft 41 are equipped with air intake channels 45. The lower end of the air intake channel 45 is connected to the connecting valve 8 via a flexible hose 84, and the upper end of the air intake channel 45 is connected to the gas chromatograph-mass spectrometer 9. In this embodiment, by setting up the air intake channel, when the extraction tube 61 moves directly below the connecting valve 8, the extraction tube 61 and the connecting valve 8 are sealed and connected. The VOC gas in the extraction tube 61 enters the air intake channel 45 through the connecting valve 8, and then enters the gas chromatograph-mass spectrometer 9 for detection.

[0059] like Figure 3 , Figure 8 and Figure 10 As shown, in some embodiments of the chemical wastewater VOC content detection device of this embodiment, the drive disk 4 has an installation hole 46 communicating with the first arc groove 42 to facilitate the installation of the valve 8; the valve 8 includes a valve body 81 movably passing through the installation hole 46 and a second spring 82 sleeved on the outer wall of the valve body 81; the two ends of the second spring 82 abut against the upper end face of the drive disk 4 and the upper end of the valve body 81 respectively; the valve body 81 is connected to the third cavity 40.

[0060] Specifically, under the action of the second elastic force, the valve body 81 is at the top dead center position. When the extraction tube 61 is directly below the valve body 81, with the cooperation of the first magnetic element 83 and the second magnetic element 64, the valve body 81 overcomes the elastic force of the second spring 82 and moves downward, so that the lower end face of the valve body 81 seals against the upper end face of the extraction tube 61, thereby sealing and connecting the valve body 81 with the extraction tube 61. This allows the VOC gas in the extraction tube 61 to enter the gas chromatograph-mass spectrometer 9 for detection after passing through the valve body 81, the hose 84, and the gas priming channel 45.

[0061] like Figure 2 , Figure 3 and Figure 11 As shown, in some embodiments of the chemical wastewater VOC content detection device of this embodiment, the rotating disk 3 has a second arc groove 32 inside the tube body 31, and the lower end of the extraction tube 61 is slidably connected in the second arc groove 32; the conductive terminal 33 is located in the second arc groove 32 and between the two extraction tubes 61. In this embodiment, by setting the second arc groove 32, the extraction mechanism can be installed. When the driving disk 4 moves up and down, the driving disk 4 cooperates with the third spiral groove 52 and the fourth spiral groove 53 through the third pin 411, so that the extraction tube 61 moves along the trajectory of the second arc groove 32, so as to ensure that the extraction tube 61 reliably moves to the position corresponding to the conductive terminal 33, so that the heating rod 62 makes electrical contact with the conductive terminal 33 and conducts electricity, thereby performing thermal desorption-gas chromatography detection on the extraction strip 63.

[0062] like Figures 2 to 4 , Figure 11 and Figure 12 As shown, in some embodiments of the chemical wastewater VOC content detection device of this embodiment, a fourth locking pin 74 protrudes from the inner wall of the piston column 7, and a fifth spiral groove 34 is provided on the outer wall of the tube body 31. The fourth locking pin 74 is movably embedded in the fifth spiral groove 34. In this embodiment, by setting the fourth locking pin 74 to cooperate with the fifth spiral groove 34, the rotating disk 3 rotates during the up-and-down movement of the piston column 7, thereby completing the extraction of the sample liquid by the two extraction strips 63.

[0063] The above description is only a preferred embodiment of the present invention. Therefore, any equivalent changes or modifications made to the structure, features and principles described in the claims of this patent application are included within the protection scope of this patent application.

Claims

1. A device for detecting VOC content in chemical wastewater, characterized in that, The sample includes a sampling housing, a sampling container at the lower end of the sampling housing, a rotating disk at the top of the sampling container, and a tube in the middle of the rotating disk; a driving disk is movably provided at the upper end of the tube, the upper end of the driving disk extends upward through the sampling housing and is movably fitted with an adjusting ring for sliding the driving disk relative to the tube; the rotating disk slides within the tube and is connected to two extraction mechanisms that communicate with the sampling container. The sampling housing has a piston rod that is slidably connected to the outer wall of the tube and is driven by the outer wall of the tube. The upper end of the piston rod extends outward through the sampling housing. When the piston rod moves up and down relative to the sampling housing, it can drive the rotating disk to rotate. The drive disk is equipped with a connecting valve, which is connected to the gas chromatograph-mass spectrometer through the drive disk; the bottom of the connecting valve is equipped with a first magnetic component; the top of the extraction mechanism is equipped with a second magnetic component; the extraction mechanism is connected to the drive disk in a transmission manner, and when the drive disk slides, the drive disk causes one of the extraction mechanisms to move relative to the bottom of the connecting valve. A sampling chamber is formed between the sampling container and the rotating disk. A first cavity communicating with the sampling chamber is formed between the sampling shell, the rotating disk, the tube, and the piston column. A second cavity is formed between the sampling shell, the piston column, the tube, and the drive disk. A third cavity communicating with the second cavity is formed between the drive disk, the tube, and the rotating disk. A conductive terminal is provided on the rotating disk directly below the connecting valve. The extraction mechanism includes an extraction tube located in the third chamber, a heating rod disposed inside the extraction tube, and an extraction strip slidably sleeved on the outer wall of the heating rod; the upper end of the heating rod is connected to the upper end of the extraction tube; a first spring is provided between the upper end of the extraction strip and the upper end of the extraction tube; the extraction strip is sealed to the inner wall of the extraction tube, so that the upper end of the extraction tube is connected to the third chamber and the lower end of the extraction tube is connected to the sampling chamber; the first spring causes the extraction strip to be housed inside the extraction tube; a first magnetic element is disposed on the upper end face of the extraction tube; The inner wall of the extraction tube is provided with a first track, which includes a first vertical groove and a first spiral groove. The upper end of the first spiral groove is connected to the lower end of the first vertical groove. The upper end of the first vertical groove is provided with a locking groove that smoothly transitions to the first vertical groove. The extraction strip is provided with a first pin, which is movably embedded in the first track. A sealing ring is sleeved on the outer wall of the first pin. A thermal expansion body is embedded in the first pin, which can protrude outward from the first pin when its temperature reaches the deformation temperature threshold.

2. The VOC content detection device for chemical wastewater according to claim 1, characterized in that, The bottom surface of the drive plate is provided with a first arc groove, and the groove wall of the first arc groove is provided with two rotationally symmetrical second tracks, the second tracks including a second vertical groove and a second spiral groove; the outer wall of the extraction tube is provided with a second pin, which is movably embedded in the corresponding second track.

3. The VOC content detection device for chemical wastewater according to claim 2, characterized in that, The inner wall of the adjusting ring is provided with a third track, and the center of the top surface of the drive disk is provided with a central shaft that protrudes out of the sampling housing. The adjusting ring is movably sleeved on the outer wall of the central shaft, and the outer wall of the central shaft is provided with a third pin that is movably embedded in the third track. The third track includes a first horizontal groove, a third spiral groove extending downwards, and a fourth spiral groove extending upwards; the two ends of the first horizontal groove are respectively connected to the upper end of the third spiral groove and the lower end of the fourth spiral groove; initially, the third pin is located in the first horizontal groove.

4. The VOC content detection device for chemical wastewater according to claim 3, characterized in that, The lower end of the third spiral groove is connected to the second horizontal groove; the upper end of the fourth spiral groove is connected to the third horizontal groove.

5. The VOC content detection device for chemical wastewater according to claim 3, characterized in that, Both the drive disc and the central shaft are equipped with air intake channels. The lower end of the air intake channel is connected to the connecting valve via a hose, and the upper end of the air intake channel is connected to the gas chromatograph-mass spectrometer.

6. The VOC content detection device for chemical wastewater according to claim 5, characterized in that, The drive disc has a mounting hole that communicates with the first arc groove; the connecting valve includes a valve body that moves through the mounting hole and a second spring that is sleeved on the outer wall of the valve body; the two ends of the second spring abut against the upper end face of the drive disc and the upper end of the valve body, respectively; the valve body communicates with the third cavity.

7. The VOC content detection device for chemical wastewater according to claim 1, characterized in that, The rotating disk has a second arc groove inside the tube, and the lower end of the extraction tube is slidably connected in the second arc groove; the conductive terminal is located in the second arc groove and between the two extraction tubes.

8. The VOC content detection device for chemical wastewater according to claim 1, characterized in that, The inner wall of the piston rod is provided with a fourth retaining pin, and the outer wall of the tube is provided with a fifth spiral groove. The fourth retaining pin is movably embedded in the fifth spiral groove.

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