Device and method for detecting perfluorinated compounds in water body

Abstract

The invention relates to a device and method for detecting perfluorinated compounds in water, and relates to the technical field of water detection.The device comprises a workbench, a circular truncated cone base is arranged on the upper end face of the workbench, at least three rotatable mixing barrels are arranged above the circular truncated cone base, and three test tubes are arranged in each mixing barrel; the bottom ends of the three test tubes are arranged on the supporting plate, the device further comprises a rotating assembly, a movable sealing cover piece and a follow-up jacking piece, the movable sealing cover piece comprises a deflection part and an elastic abutting part, and the elastic abutting part is driven to synchronously deflect through deflection of the deflection part. The pushing strip periodically pushes the ejector rod to drive the supporting plate to swing back and forth around a hinge point, so that the test tubes are superposed and shake up and down on the basis of rotary stirring to form a dual mixing effect, the problem of sample layering or insufficient local mixing is effectively avoided, and the sample and an additive are ensured to fully react.

Description

Technical Field

[0001] This invention relates to the field of water body detection technology, and in particular to a device and method for detecting perfluorinated compounds in water. Background Technology

[0002] Perfluorinated compounds (PFAS), as a class of organic compounds with strong chemical stability, are widely used in industrial production and daily consumer goods due to their high-temperature resistance, water and oil resistance, and other properties. However, these compounds are difficult to degrade naturally and tend to persist in environmental media such as water and soil. They also accumulate in organisms through the food chain, posing a potential threat to the ecological environment and human health. Therefore, establishing an efficient and accurate detection system for perfluorinated compounds in water is crucial.

[0003] Currently, the sample processing stage before detecting perfluorinated compounds in water still has some shortcomings. Most traditional detection devices can only achieve stirring and mixing of a single sample, which is difficult to meet the needs of simultaneous processing of multiple water samples, resulting in low detection efficiency. A search revealed a screening device and method for perfluorinated compounds in water in patent application number 202310836800.6. In this method, the rotation of a driven gear drives the rotation of a third rotating rod and a driven gear. The rotation of the third rotating rod and multiple driven gears facilitates the stirring and mixing of the water to be tested in the installation cylinder. Although it can achieve the rotation and stirring of multiple installation cylinders at one time, the mixing method is a single rotation stirring. The uniformity of the sample and additives is insufficient, and local incomplete reactions are likely to occur, which will affect the accuracy of subsequent detection results. In addition, the sealing operation of the sample container is cumbersome, requiring the sealing of each test tube individually. This not only increases the manual operation intensity, but also may lead to sample leakage or contamination due to improper sealing, which restricts the efficient implementation of detection work. Based on this, a device and method for detecting perfluorinated compounds in water is proposed here. Summary of the Invention

[0004] To overcome the problems existing in related technologies, the present invention provides a device and method for detecting perfluorinated compounds in water. Through the linkage design of the follow-up lifting component and the rotating component, during the rotation of the mixing cylinder, the push bar periodically pushes the top rod, causing the tray to swing back and forth around the hinge point, so that the test tube is superimposed with up and down shaking on the basis of rotation and stirring, forming a double mixing effect.

[0005] To achieve the above objectives, the present invention provides a device for detecting perfluorinated compounds in water, comprising a workbench, a frustum-shaped base on the upper surface of the workbench, at least three rotatable mixing cylinders above the frustum-shaped base, each mixing cylinder containing three test tubes, the bottom ends of the three test tubes being mounted on a support plate, the support plate being hinged to the bottom of the mixing cylinder, and further comprising: A rotating assembly, mounted on the worktable, is used to drive all the mixing cylinders to rotate synchronously; The movable sealing component includes a deflecting part and an elastic pressing part. The deflecting part is movably connected to the rotating assembly. The deflection of the deflecting part drives the elastic pressing part to deflect synchronously, so as to realize the synchronous sealing or opening of all the upper ports of the mixing cylinder. The elastic pressing part can be raised and lowered. The follower lifting component is connected to the rotating assembly at one end and is eccentrically and vertically arranged below the pallet at the other end. When the rotating assembly drives all the mixing cylinders to rotate, the follower lifting component can periodically push the pallet upward, causing the pallet to swing around the hinge point.

[0006] Preferably, the rotating assembly includes: A drive motor is fixedly mounted below the worktable, and a connecting shaft is installed at the output end of the drive motor. The connecting shaft vertically penetrates the surface of the worktable. The first gear is mounted on the top of the connecting shaft; A toothed ring is fixed to the lower outer end of each of the mixing cylinders, and all of the toothed rings mesh with the first gear for transmission.

[0007] Preferably, the deflection section includes: A top plate, wherein a connecting rod is fixed to the lower end face of the top plate, and the bottom end of the connecting rod is rotatably connected to the upper end face of the first gear through a bearing; The second gear is fixed to the outside of the connecting rod; A first telescopic rod is vertically installed inside the workbench, and a third gear is mounted on the top of the first telescopic rod via a bearing seat. A fourth gear is mounted above the third gear via a shaft. By raising and lowering the first telescopic rod, the third gear can engage or disengage with the first gear, and the fourth gear can engage or disengage with the second gear.

[0008] Preferably, each mixing cylinder is provided with an elastic pressing part, and the elastic pressing part includes a second telescopic rod, which is vertically installed through the top plate, and the bottom end of the second telescopic rod is connected to a connecting plate through a bearing. The lower end face of the connecting plate is connected to the cover plate through several elastic connecting columns.

[0009] Preferably, the diameter of the cover plate is adapted to the inner diameter of the mixing cylinder, and a sealing gasket is rotatably installed on the lower end face of the cover plate.

[0010] Preferably, the follower lifting member includes a push bar fixed on the connecting shaft, and one side of the push bar is provided with a push slope.

[0011] Preferably, the follower lifting member further includes: The top rod slides vertically through the worktable and the frustum base at its upper end and extends to the bottom of the mixing cylinder, correspondingly positioned below the support plate; A convex ring is fixed to the outside of the top rod, and a first return spring is connected between the upper end face of the convex ring and the lower end face of the worktable. The pressure block is fixed to the bottom end of the top rod, and a pressure inclined surface is provided on one side of the pressure block.

[0012] Preferably, a second return spring is connected between the lower end face of the tray away from the hinge point and the inner bottom of the mixing cylinder.

[0013] Preferably, a rotating ring is fixed at the bottom of the mixing cylinder, and a sliding groove adapted to the rotating ring is provided on the upper surface of the frustum base. The rotating ring is embedded in the sliding groove and slides in cooperation with the sliding groove.

[0014] This invention also provides a method for detecting perfluorinated compounds in water, using the aforementioned detection device for perfluorinated compounds in water, comprising the following steps: S1. Place the water sample containing perfluorinated compounds to be tested and the corresponding additives into three test tubes respectively. Then place the three test tubes containing the same water sample into a mixing cylinder and stably support the test tubes on the tray. S2. Control the extension of the first telescopic rod to drive the third and fourth gears to move upward, so that the third gear meshes with the first gear and the fourth gear meshes with the second gear. Start the drive motor, drive the first gear to rotate through the connecting shaft, and drive the connecting rod and the top plate to deflect through the third gear, the fourth gear and the second gear, so that the cover plate of each elastic pressing part is located directly above the upper port of the mixing cylinder. Then turn off the drive motor, control the first telescopic rod to retract, so that the third gear disengages from the first gear and the fourth gear disengages from the second gear. Then control the extension of the second telescopic rod to drive the cover plate to move downward, and achieve the sealing of the upper port of the test tube by the sealing gasket adhering to the upper end face of the mixing cylinder. S3. Start the drive motor, and through the meshing transmission of the first gear and each gear ring, drive all the mixing cylinders to rotate synchronously, and stir and mix the samples in the test tubes; S4. During the rotation of the mixing cylinder, the connecting shaft drives the push bar to rotate synchronously. The pushing slope of the push bar periodically contacts and pushes the pressure slope of different pressure blocks, causing the push rod to overcome the elastic force of the first reset spring and push the support plate upward. The support plate swings around the hinge point, causing the test tube to shake up and down. When the push bar disengages from the pressure block, the push rod resets under the action of the first reset spring, and the support plate resets under the action of the second reset spring. This cycle is repeated to achieve the periodic extension and shaking of the test tube. After maintaining the above state for a preset time, the drive motor is turned off to complete the mixing of the sample.

[0015] The technical solution provided by this invention may include the following beneficial effects: 1. In this invention, through the linkage design of the follow-up lifting component and the rotating component, during the rotation of the mixing cylinder, the pushing bar periodically pushes the top rod, causing the tray to swing back and forth around the hinge point, so that the test tube is superimposed with up and down shaking on the basis of rotation and stirring, forming a double mixing effect, effectively avoiding the problem of sample stratification or insufficient local mixing, ensuring that the sample and additives react fully, and providing a uniform and stable sample basis for subsequent detection.

[0016] 2. In this invention, at least three mixing cylinders can be driven to rotate synchronously by the meshing transmission between the first gear in the rotating assembly and the external toothed rings of multiple mixing cylinders. Each mixing cylinder can hold three sets of water sample tubes of the same type, which can complete the mixing of multiple sets of samples at one time. Compared with the traditional processing mode, it significantly reduces the sample preparation time and meets the requirements of batch testing.

[0017] 3. In this invention, the deflection part of the movable sealing part cooperates with the elastic pressing part to achieve synchronous sealing and opening of all mixing cylinder ports, eliminating the need for individual sealing operations and simplifying the process. At the same time, the design of the sealing gasket and elastic connecting column of the elastic pressing part ensures the tightness of the seal and prevents sample leakage, while also having a certain buffering capacity to avoid damage to the test tubes caused by rigid compression and reduce the risk of sample contamination.

[0018] 4. In this invention, the mixing cylinder achieves smooth rotation through the cooperation of the rotating ring and the sliding groove of the truncated cone base, and the follower lifting component is reset by means of a reset spring. The transmission paths of each component are clear and the linkage is coordinated, resulting in high overall structural stability. It can also adapt to different batch testing requirements, and the operation process is easy to control. It is suitable for perfluorinated compound testing scenarios in various water bodies such as drinking water, surface water, and wastewater, and has broad application value.

[0019] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0020] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same parts in the exemplary embodiments of the invention.

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a front view of the present invention; Figure 3 This is the present invention. Figure 1 A schematic diagram of the overall structure from another angle; Figure 4This is a schematic diagram of the structure of the mixing cylinder, rotating assembly, movable sealing cover, and follower lifting component of the present invention; Figure 5 This is a schematic diagram of the structure of the movable sealing component of the present invention; Figure 6 This is a schematic diagram of the structure of the mixing cylinder, rotating assembly, follower lifting component, and test tube of the present invention; Figure 7 This is the present invention. Figure 6 A schematic diagram of the cross-sectional structure; Figure 8 This is a schematic diagram of the test tube and the follower lifting component in cross-sectional view of the mixing cylinder of the present invention; Figure 9 This is a schematic diagram of the structure of the support plate and the top rod of the present invention; Figure 10 This is a schematic diagram of the top rod of the present invention.

[0022] The correspondence between the labels and component names in the attached figures is as follows: 1. Workbench; 2. Frustum base; 21. Sliding groove; 3. Mixing cylinder; 31. Rotating ring; 4. Rotating assembly; 41. Drive motor; 42. Connecting shaft; 43. First gear; 44. Gear ring; 5. Movable cover; 51. Deflecting part; 511. Top plate; 512. Connecting rod; 513. Second gear; 514. First telescopic rod; 515. Third gear; 516. Fourth gear; 52. Elastic pressing part; 521. Second telescopic rod; 522. Connecting plate; 523. Elastic connecting column; 524. Cover plate; 6. Follower lifting component; 61. Push bar; 611. Pushing inclined surface; 62. Push rod; 63. Convex ring; 64. First return spring; 65. Pressure block; 651. Pressure inclined surface; 66. Second return spring; 7. Test tube; 71. Tray; 72. Test tube holder. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this invention. Preferred embodiments of the invention will now be described in more detail with reference to the accompanying drawings. Although preferred embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to make the invention more thorough and complete, and to fully convey the scope of the invention to those skilled in the art.

[0024] The technical solutions of the embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0025] Example 1: See Figures 1-10 As shown, this invention proposes a device for detecting perfluorinated compounds in water, including a workbench 1, a controller, and a detection instrument (high-performance liquid chromatography-mass spectrometry, not shown). The workbench 1 is made of high-strength, corrosion-resistant stainless steel, which can not only effectively support the weight of the components of the device, but also resist corrosion from chemical reagents that may be generated during water detection. A frustum 2 is provided on the upper surface of the workbench 1, and at least three rotatable mixing cylinders 3 are provided above the frustum 2. Specifically, a rotating ring 31 is fixed at the bottom of the mixing cylinder 3. The outer circumferential surface of the rotating ring 31 is treated with a smooth, wear-resistant coating to reduce friction during rotation. A sliding groove 21 adapted to the rotating ring 31 is opened on the upper surface of the frustum 2. The rotating ring 31 is embedded in the sliding groove 21 and slides in cooperation with the sliding groove 21. The inner sidewall of the sliding groove 21 is polished, and the groove is... A small amount of highly lubricating, chemically inert lubricant is applied to further improve the smoothness and stability of the rotation of the mixing cylinder 3. Each mixing cylinder 3 is equipped with three test tubes 7. The test tubes 7 are hard glass test tubes that meet laboratory standards. Their volume is designed according to the sample quantity requirements for the detection of perfluorinated compounds in water. The bottom ends of the three test tubes 7 are set on the support plate 71. Three test tube holders 72 are fixed in a circular array on the upper end face of the support plate 71. The bottom ends of the test tubes 7 are installed in the test tube holders 72. The test tube holders 72 can be made of a composite of elastic rubber and hard plastic. The inner side of the holder has an arc-shaped groove that matches the outer diameter of the bottom end of the test tube 7. The inner wall of the groove has anti-slip texture, which can not only firmly install the bottom end of the test tube 7 in the test tube holder 72 to achieve stable positioning of the test tube 7, but also avoid damage to the test tube 7 caused by rigid clamping. The support plate 71 is hinged to the bottom of the mixing cylinder 3.

[0026] In addition, it also includes a rotating assembly 4 and a movable sealing cover 5. The rotating assembly 4 is mounted on the worktable 1 and is used to drive all mixing cylinders 3 to rotate synchronously. The movable sealing cover 5 includes a deflecting part 51 and an elastic pressing part 52, which are integrated and linked. The deflecting part 51 is movably connected to the rotating assembly 4. The deflection of the deflecting part 51 drives the elastic pressing part 52 to deflect synchronously, so as to realize the synchronous sealing or opening of the upper ports of all mixing cylinders 3. There is no need to seal / open them one by one, simplifying the operation process. The elastic pressing part 52 has a height-adjustable function.

[0027] Among them, see Figures 1-4 as well as Figures 6-7 As shown, the rotating assembly 4 includes a drive motor 41 and a gear ring 44. The drive motor 41 is fixedly installed below the workbench 1. The output end of the drive motor 41 is connected to a connecting shaft 42 via a coupling. The connecting shaft 42 vertically penetrates the surface of the workbench 1, and the connecting shaft 42 is connected to the through hole of the workbench 1 via a sealed bearing, which ensures smooth rotation of the connecting shaft 42 and prevents external impurities from entering. A first gear 43 is installed at the top of the connecting shaft 42. A gear ring 44 is fixed at the lower outer end of each mixing cylinder 3. All gear rings 44 are arranged in a circular array around the first gear 43. All gear rings 44 mesh with the first gear 43 for transmission. When the drive motor 41 is started, the output end of the drive motor 41 drives the connecting shaft 42 to rotate, which in turn drives each gear ring 44 to rotate synchronously through the first gear 43. This achieves simultaneous mixing and stirring of water samples in multiple mixing cylinders 3. Compared with the traditional single-cylinder stirring mode, multiple sets of samples can be processed at one time, improving the sample preparation efficiency before detection.

[0028] See Figures 1-5As shown, the deflection part 51 includes a top plate 511 and a first telescopic rod 514. The first telescopic rod 514 can be an electric telescopic rod. A connecting rod 512 is fixed to the lower end face of the top plate 511. The bottom end of the connecting rod 512 is rotatably connected to the upper end face of the first gear 43 via a bearing. A second gear 513 is fixed to the outside of the connecting rod 512. The first telescopic rod 514 is vertically installed through the workbench 1, and a third gear 515 is installed at the top end of the first telescopic rod 514 via a bearing seat. A fourth gear 516 is installed above the third gear 515 via a shaft. The distance between the third gear 515 and the fourth gear 516 is greater than the thickness of the fourth gear 516. The distance between the first gear 43 and the upper end face of the frustum 2 is greater than the thickness of the third gear 515. By raising and lowering the first telescopic rod 514, the deflection part 51 can... The third gear 515 is engaged or disengaged from the first gear 43, and the fourth gear 516 is engaged or disengaged from the second gear 513. When the third gear 515 is engaged with the first gear 43, the power generated by the rotation of the first gear 43 is transmitted to the third gear 515. The third gear 515 drives the fourth gear 516 to rotate synchronously through the shaft. The fourth gear 516 then drives the engaged second gear 513 to rotate. The second gear 513 drives the connecting rod 512 and the top plate 511 at the top to rotate synchronously, thereby realizing the deflection adjustment of the elastic pressing part 52. When the first telescopic rod 514 retracts and disengages the third gear 515 from the first gear 43, the rotation of the first gear 43 will only drive the toothed rings 44 and the mixing cylinder 3 to rotate, without driving the deflection part 51 to move, thus realizing the precise switching of the power transmission path.

[0029] See Figures 1-5 As shown, each mixing cylinder 3 is provided with an elastic pressing part 52, and the elastic pressing part 52 includes a second telescopic rod 521. The second telescopic rod 521 can be an electric telescopic rod. The second telescopic rod 521 is vertically installed on the top plate 511, and the bottom end of the second telescopic rod 521 is connected to a connecting plate 522 via a bearing. The lower end face of the connecting plate 522 is connected to a cover plate 524 via several elastic connecting columns 523. The elastic connecting column 523 is composed of an outer cylinder and a straight rod. The straight rod is slidably connected to the inside of the outer cylinder, and the inner end of the straight rod and A spring connects the inner parts of the outer cylinder. Through the elasticity and expansion of the spring, the cover plate 524 can have a certain buffering and adjustment capability. The cover plate 524 is made of corrosion-resistant material, and its diameter is adapted to the inner diameter of the mixing cylinder 3. A sealing gasket is rotatably installed on the lower end face of the cover plate 524. The sealing gasket is equivalent to a sealing plug and is made of highly elastic and corrosion-resistant rubber material. It can not only enhance the sealing effect and prevent water sample from overflowing during the mixing process, but also rotate synchronously when the mixing cylinder 3 rotates, reducing friction interference.

[0030] Based on the above, in practical use, first place the test tube 7 containing the water sample into the corresponding mixing cylinder 3. After the sample is placed, control the first telescopic rod 514 to extend, driving the third gear 515 and the fourth gear 516 to move upward synchronously until the third gear 515 meshes with the first gear 43 and the fourth gear 516 meshes with the second gear 513. At this time, the power transmission path is connected, and the drive motor 41 is started. The motor output end drives the first gear 43 to rotate through the connecting shaft 42. The first gear 43 transmits power to the third gear 515. The third gear 515 drives the fourth gear 516 to rotate through the shaft. The fourth gear 516 then drives the second gear 513 and the connecting rod 512 to rotate. The connecting rod 512 drives the top plate 511 to deflect synchronously until the cover plate 524 of each elastic pressing part 52 is precisely aligned above the upper port of its respective mixing cylinder 3. After the alignment is completed, the drive motor 41 is turned off. 1. Subsequently, the first telescopic rod 514 is controlled to retract, driving the third gear 515 and the fourth gear 516 to move downwards, causing the third gear 515 to disengage from the first gear 43 and the fourth gear 516 to disengage from the second gear 513, cutting off the power transmission of the deflection part 51. Then, all the second telescopic rods 521 are controlled to extend synchronously, driving the cover plate 524 and the sealing gasket to move downwards until the sealing gasket enters the interior of the mixing cylinder 3. Under the elastic force of the elastic connecting column 523, the sealing gasket reliably seals the upper port of the test tube 7. Conversely, when it is necessary to open, it is only necessary to control the second telescopic rod 521 to retract, which will drive the cover plate 524 to move upwards, realizing the synchronous opening of the upper ports of all test tubes 7. This design can complete the sealing or opening operation of multiple sets of test tubes 7 at one time, effectively reducing manual operation steps, improving the overall efficiency in the water sample detection process, and ensuring the reliability of sealing and the stability of operation.

[0031] Example 2: See Figures 1-2 as well as Figures 4-9 As shown, this embodiment is an extension of Embodiment 1. The detection device also includes a follower lifting member 6, which works in conjunction with the rotation of the mixing cylinder 3 to agitate and mix the water sample in the test tube 7, thereby improving the mixing uniformity and detection accuracy. One end of the follower lifting member 6 is linked to the rotating component 4 to ensure synchronous power transmission. The other end of the follower lifting member 6 is eccentrically and vertically arranged below the support plate 71. When the rotating component 4 drives all the mixing cylinders 3 to rotate, the follower lifting member 6 can periodically push the end of the support plate 71 away from the hinge point upwards, causing the support plate 71 to swing back and forth around the hinge point, thereby causing the test tube 7 above to tilt and shake. This allows the water sample to be agitated and shaken while rotating and stirring, achieving more thorough mixing.

[0032] The follower lifting component 6 includes a pusher bar 61 fixed on the connecting shaft 42, and a pusher inclined surface 611 is provided on one side of the pusher bar 61. The follow-up lifting component 6 also includes a push rod 62. The upper end of the push rod 62 slides vertically through the worktable 1 and the frustum 2, and extends to the bottom of the mixing cylinder 3. It is correspondingly positioned below the support plate 71. A convex ring 63 is fixed to the outside of the push rod 62. Several first return springs 64 are connected between the upper end face of the convex ring 63 and the lower end face of the worktable 1. A pressure block 65 is fixed to the bottom end of the push rod 62. A pressure inclined surface 651 is provided on one side of the pressure block 65. The pressure inclined surface 651 is adapted to the pushing inclined surface 611 of the pushing strip 61. The two inclined surfaces have the same inclination angle and smooth surface, which can realize sliding pushing after close contact. A second return spring 66 is connected between the lower end face of the support plate 71 away from the hinge point and the bottom of the mixing cylinder 3. The second return spring 66 is used for the return swing of the support plate 71 after it is pushed.

[0033] As described above, after sealing the test tube 7, the drive motor 41 is started, and the connecting shaft 42 drives the first gear 43 and the pusher bar 61 to rotate synchronously. The first gear 43 drives the mixing cylinder 3 to rotate to achieve stirring, while the pusher bar 61 rotates with the connecting shaft 42. During the rotation of the pusher bar 61, its pushing slope 611 will contact and adhere to the pressure slope 651 of the pressure block 65. As the connecting shaft 42 continues to rotate, the pushing slope 611 generates a horizontal pushing force on the pressure slope 651. This force is decomposed into an upward lifting force, which pushes the pressure block 65 and the push rod 62 to move upward. The upper end of the push rod 62 pushes the support plate 71, causing the support plate 71 to swing upward around the hinge point. Simultaneously, the first return spring 64 is compressed and the second return spring 66 is compressed. When the push bar 61 rotates to disengage from the pressure block 65, the pushing force disappears, the first return spring 64 releases its elasticity, pulls the top rod 62 downward to reset, and the pressure block 65 returns to its initial position. At the same time, the second return spring 66 drives the support plate 71 to reset to a horizontal state. This cycle repeats. As the connecting shaft 42 continues to rotate, the top rod 62 rises and falls periodically, and the support plate 71 swings back and forth. Under the dual action of rotation and stirring and reciprocating shaking, the water sample in the test tube 7 is mixed more evenly and thoroughly, effectively improving the sample mixing quality and providing a reliable sample basis for subsequent testing.

[0034] This invention also proposes a method for detecting perfluorinated compounds in water, using the aforementioned detection device for perfluorinated compounds in water, comprising the following steps: S1. The water sample containing perfluorinated compounds to be tested and the corresponding additives are respectively placed into three test tubes 7. Then, the three test tubes 7 containing the same water sample are placed into a mixing cylinder 3, so that the test tubes 7 are stably supported on the support plate 71. S2. Control the extension of the first telescopic rod 514 to drive the third gear 515 and the fourth gear 516 to move upward, so that the third gear 515 meshes with the first gear 43 and the fourth gear 516 meshes with the second gear 513. Start the drive motor 41, drive the first gear 43 to rotate through the connecting shaft 42, and drive the connecting rod 512 and the top plate 511 to deflect through the third gear 515, the fourth gear 516 and the second gear 513, so that the cover plate 524 of each elastic pressing part 52 is located directly above the upper port of the mixing cylinder 3. Then turn off the drive motor 41, control the first telescopic rod 514 to retract, so that the third gear 515 disengages from the first gear 43 and the fourth gear 516 disengages from the second gear 513. Then control the extension of the second telescopic rod 521 to drive the cover plate 524 to move downward, and achieve the sealing of the upper port of the test tube 7 by the sealing gasket adhering to the upper end face of the mixing cylinder 3. S3. Start the drive motor 41, and drive all the mixing cylinders 3 to rotate synchronously through the meshing transmission of the first gear 43 and each gear ring 44, so as to stir and mix the sample in the test tube 7. S4. During the rotation of the mixing cylinder 3, the connecting shaft 42 drives the pusher bar 61 to rotate synchronously. The pushing slope 611 of the pusher bar 61 periodically contacts and pushes the pressure slope 651 of different pressure blocks 65, causing the top rod 62 to overcome the elastic force of the first reset spring 64 and push the support plate 71 upward. The support plate 71 swings around the hinge point, causing the test tube 7 to shake up and down. When the pusher bar 61 is separated from the pressure block 65, the top rod 62 is reset under the action of the first reset spring 64, and the support plate 71 is reset under the action of the second reset spring 66. This cycle is repeated to realize the periodic extension and retraction of the test tube 7. After maintaining the above state for a preset time, the drive motor 41 is turned off to complete the mixing of the sample.

[0035] After the water samples are mixed, a suitable amount of the well-mixed water sample is extracted from each test tube using a sterile pipette or sampling spoon and transferred to a dedicated detection instrument (high performance liquid chromatography-mass spectrometry) for detection. During detection, the pre-treated sample is first separated by the high performance liquid chromatography module. The adsorption and elution of the chromatographic column are used to separate different types of perfluorinated compounds in the sample. Then, the mass spectrometry module performs qualitative and quantitative analysis on the separated components. The compounds are ionized into charged ions by the ion source. The specific types of perfluorinated compounds (PFAS) in the water are identified based on the difference in the mass-to-charge ratio of the ions. At the same time, the content of each component is accurately calculated by combining the standard curve method. This method can effectively detect trace amounts of PFAS in various types of water bodies such as drinking water, surface water, and wastewater.

[0036] The present invention has been described in detail above with reference to the accompanying drawings. In the above embodiments, the descriptions of each embodiment have their own emphasis; for parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments. Those skilled in the art should also understand that the actions and modules involved in the specification are not necessarily essential to the present invention. Furthermore, it is understood that the steps in the method of the embodiments of the present invention can be adjusted, combined, and deleted according to actual needs, and the structure in the device of the embodiments of the present invention can be combined, divided, and deleted according to actual needs.

[0037] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A device for detecting perfluorinated compounds in water, comprising a workbench (1), wherein a frustum (2) is provided on the upper surface of the workbench (1), and at least three rotatable mixing cylinders (3) are provided above the frustum (2), each mixing cylinder (3) containing three test tubes (7), characterized in that, The bottom ends of the three test tubes (7) are mounted on a support plate (71), which is hinged to the bottom of the mixing cylinder (3), and also includes: A rotating assembly (4) is mounted on the workbench (1) to drive all the mixing cylinders (3) to rotate synchronously; The movable sealing part (5) includes a deflection part (51) and an elastic pressing part (52). The deflection part (51) is movably connected to the rotating assembly (4). The deflection of the deflection part (51) drives the elastic pressing part (52) to deflect synchronously, so as to realize the synchronous sealing or opening of the upper ports of all the mixing cylinders (3). The elastic pressing part (52) can be raised and lowered. The follower lifting member (6) is connected to the rotating component (4) at one end and is eccentrically and vertically arranged below the tray (71) at the other end. When the rotating component (4) drives all the mixing cylinders (3) to rotate, the follower lifting member (6) can periodically push the tray (71) upward, so that the tray (71) swings around the hinge point.

2. The device for detecting perfluorinated compounds in water according to claim 1, characterized in that, The rotating assembly (4) includes: A drive motor (41) is fixedly mounted below the worktable (1). A connecting shaft (42) is installed at the output end of the drive motor (41). The connecting shaft (42) vertically penetrates the table surface of the worktable (1). The first gear (43) is mounted on the top of the connecting shaft (42); A toothed ring (44) is fixed to the lower outer end of each of the mixing cylinders (3), and all of the toothed rings (44) mesh with the first gear (43) for transmission.

3. The device for detecting perfluorinated compounds in water according to claim 2, characterized in that, The deflection section (51) includes: A top plate (511) is provided with a connecting rod (512) fixed to its lower end face. The bottom end of the connecting rod (512) is rotatably connected to the upper end face of the first gear (43) via a bearing. The second gear (513) is fixed to the outside of the connecting rod (512); The first telescopic rod (514) is vertically installed inside the workbench (1), and the top of the first telescopic rod (514) is equipped with a third gear (515) through a bearing seat. The third gear (515) is equipped with a fourth gear (516) through a shaft above it. By raising and lowering the first telescopic rod (514), the third gear (515) can mesh or disengage from the first gear (43), and at the same time, the fourth gear (516) can mesh or disengage from the second gear (513).

4. The device for detecting perfluorinated compounds in water according to claim 3, characterized in that, Each mixing cylinder (3) is provided with an elastic pressing part (52), and the elastic pressing part (52) includes a second telescopic rod (521). The second telescopic rod (521) is vertically installed on the top plate (511), and the bottom end of the second telescopic rod (521) is connected to a connecting plate (522) through a bearing. The lower end face of the connecting plate (522) is connected to a cover plate (524) through several elastic connecting columns (523).

5. The device for detecting perfluorinated compounds in water according to claim 4, characterized in that, The diameter of the cover plate (524) is adapted to the inner diameter of the mixing cylinder (3), and a sealing gasket is rotatably installed on the lower end face of the cover plate (524).

6. The device for detecting perfluorinated compounds in water according to claim 2, characterized in that, The follower lifting member (6) includes a push bar (61) fixed on the connecting shaft (42), and one side of the push bar (61) is provided with a push slope (611).

7. The device for detecting perfluorinated compounds in water according to claim 6, characterized in that, The follower lifting component (6) also includes: The top rod (62) slides vertically through the worktable (1) and the frustum (2) at its upper end and extends to the bottom of the mixing cylinder (3), and is correspondingly located below the tray (71); A convex ring (63) is fixed to the outside of the top rod (62), and a first return spring (64) is connected between the upper end face of the convex ring (63) and the lower end face of the worktable (1). The pressure block (65) is fixed to the bottom end of the top rod (62), and a pressure inclined surface (651) is provided on one side of the pressure block (65).

8. The device for detecting perfluorinated compounds in water according to claim 7, characterized in that, A second return spring (66) is connected between the lower end face of the tray (71) away from the hinge point and the inner bottom of the mixing cylinder (3).

9. The device for detecting perfluorinated compounds in water according to claim 1, characterized in that, The bottom end of the mixing cylinder (3) is fixed with a rotating ring (31), and the upper end surface of the truncated cone (2) is provided with a sliding groove (21) that is adapted to the rotating ring (31). The rotating ring (31) is embedded in the sliding groove (21) and slides in cooperation with the sliding groove (21).

10. A method for detecting perfluorinated compounds in water, characterized in that, The device for detecting perfluorinated compounds in water as described in any one of claims 1-9 comprises the following steps: S1. The water sample containing perfluorinated compounds to be tested and the corresponding additives are respectively placed into three test tubes (7). Then, the three test tubes (7) containing the same water sample are placed into a mixing cylinder (3) so that the test tubes (7) are stably supported on the tray (71). S2. Control the extension of the first telescopic rod (514), which drives the third gear (515) and the fourth gear (516) to move upward, so that the third gear (515) meshes with the first gear (43) and the fourth gear (516) meshes with the second gear (513). Start the drive motor (41), which drives the first gear (43) to rotate through the connecting shaft (42). Through the transmission of the third gear (515), the fourth gear (516) and the second gear (513), the connecting rod (512) and the top plate (511) deflect. The cover plate (524) of each elastic pressing part (52) is positioned directly above the upper port of the mixing cylinder (3). Then, the drive motor (41) is turned off, and the first telescopic rod (514) is controlled to retract, so that the third gear (515) disengages from the first gear (43) and the fourth gear (516) disengages from the second gear (513). Then, the second telescopic rod (521) is controlled to extend, driving the cover plate (524) to move down and adhere to the upper end face of the mixing cylinder (3) through the sealing gasket, thereby achieving the sealing and plugging of the upper port of the test tube (7). S3. Start the drive motor (41), and drive all the mixing cylinders (3) to rotate synchronously through the meshing transmission of the first gear (43) and each gear ring (44) to stir and mix the sample in the test tube (7); S4. During the rotation of the mixing cylinder (3), the connecting shaft (42) drives the push bar (61) to rotate synchronously. The push slope (611) of the push bar (61) periodically contacts and pushes the pressure slope (651) of different pressure blocks (65), so that the top rod (62) overcomes the elastic force of the first reset spring (64) and pushes the tray (71) upward. The tray (71) swings around the hinge point, causing the test tube (7) to shake up and down. When the push bar (61) is separated from the pressure block (65), the top rod (62) is reset under the action of the first reset spring (64), and the tray (71) is reset under the action of the second reset spring (66). This cycle is repeated to realize the periodic extension and retraction of the test tube (7). After maintaining the above state for a preset time, the drive motor (41) is turned off to complete the mixing of the sample.

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