An ammonia nitrogen on-line detection system and method in a ternary precursor production process

Abstract

This invention discloses an online ammonia nitrogen detection system and method in the production of ternary precursors. The system includes a sampling component, a vibration reaction component, a reaction liquid extraction component, a cuvette loading component, a reaction cup / cuvette transfer component, and a fixing plate. All components are integrated on the fixing plate and work collaboratively. The sampling component extracts the intermediate precursor product and standard salicylic acid solution and injects them into the reaction cup; the vibration reaction component carries the reaction cup and promotes the reaction through vibration; the reaction liquid extraction component extracts the post-reaction liquid and injects it into the cuvette; the cuvette loading component provides the cuvette; and the reaction cup / cuvette transfer component enables automatic replacement of the reaction cup and cuvette. The detection method is based on salicylic acid spectrophotometry, utilizing the linear relationship between ammonia nitrogen concentration and absorption wavelength at a 5mm optical path. Controlled by a PLC and touchscreen, the system is managed and remotely monitored by a host computer. This invention requires no manual intervention, provides accurate and efficient detection, and can optimize the control of the ternary precursor production process.

Description

Technical Field

[0001] This invention relates to the field of online ammonia nitrogen detection technology, specifically to an online ammonia nitrogen detection system in the production process of ternary precursors. Background Technology

[0002] In the preparation of high-performance ternary cathode materials, the ternary precursor, as the core raw material, has a decisive influence on the physicochemical properties of the cathode sintering product, especially its particle size distribution. The preparation of the ternary precursor involves a variety of process parameters, among which ammonia nitrogen concentration, reaction temperature, pH value during the reaction process, stirring rate, and reaction time all have a significant impact on particle size, while ammonia nitrogen concentration has the most significant effect on the particle size of the ternary precursor.

[0003] Therefore, ammonia nitrogen concentrations in intermediate products during industrial production processes are frequently monitored as a basis for process control. Existing ammonia nitrogen detection equipment is essentially semi-automated, requiring constant human intervention. It offers high accuracy and repeatability only at low concentrations, and exhibits significant deviations when detecting high concentrations of ammonia nitrogen in production processes. Summary of the Invention

[0004] To address this issue, the present invention provides an online ammonia nitrogen detection system and method for the production of ternary precursors, solving the problems of low automation and large detection deviations for high-concentration ammonia nitrogen in traditional technologies.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an online ammonia nitrogen detection system in the production process of ternary precursors, comprising a sampling component, a vibration reaction component, a reaction liquid extraction component, a cuvette feeding component, a reaction cup / cuvette transfer component, and a fixing plate;

[0006] The sampling component, the vibration reaction component, the reaction liquid extraction component, the cuvette loading component, and the reaction cup / cuvette transfer component are all mounted on a fixed plate. The sampling component extracts the precursor intermediate and standard salicylic acid solution from the reaction vessel and injects them into the reaction cup. The vibration reaction component carries the reaction cup and realizes the vibration and position adjustment of the reaction cup. The reaction liquid extraction component extracts the reaction liquid from the vibration reaction component and injects it into the cuvette. The cuvette loading component is used to provide cuvettes. The reaction cup / cuvette transfer component is used to grasp and replace the reaction cup / cuvette.

[0007] As a preferred solution for an online ammonia nitrogen detection system in the production process of ternary precursors, the sampling component includes a first lead screw stepper motor, a liquid extraction lifting motor plate, a lifting nut seat, a liquid extraction lifting support plate, a liquid extraction pipeline plate, an injection pump, a pump fixing seat, and an injection needle.

[0008] The first lead screw stepper motor is mounted on the liquid extraction lifting motor plate. The lifting nut seat cooperates with the lead screw of the first lead screw stepper motor. The liquid extraction lifting support plate is connected to the end of the lead screw of the first lead screw stepper motor. The liquid extraction pipeline plate is connected to the side of the lifting nut seat. The injection pump is mounted on the liquid extraction pipeline plate through the pump fixing seat. The injection needle is connected to the injection pump.

[0009] As a preferred solution for the online ammonia nitrogen detection system in the production process of ternary precursors, the vibration reaction assembly includes a second lead screw stepper motor, a nut connecting block, a first transverse lead screw, a mixing transverse motor support plate, a mixing beaker support plate, a vibration motor mounting base, a vibration motor, a beaker bottom plate adapter, a beaker body, and a beaker bottom plate.

[0010] The second lead screw stepper motor is mounted on the hybrid transverse motor support plate. The first transverse lead screw is connected to the second lead screw stepper motor. The nut connecting block cooperates with the first transverse lead screw. The hybrid beaker support plate is connected to the nut connecting block. The beaker bottom plate is connected to the hybrid beaker support plate through the beaker bottom plate adapter. The vibration motor mounting base is connected to the beaker bottom plate. The vibration motor is connected to the vibration motor mounting base. The beaker body is placed in the beaker placement hole on the beaker bottom plate.

[0011] As a preferred solution for the online ammonia nitrogen detection system in the production process of ternary precursors, the reaction liquid extraction component includes a third lead screw stepper motor, a liquid delivery motor mounting plate, a second transverse lead screw, a liquid delivery lifting cover plate, a liquid delivery lifting motor, a liquid delivery motor lifting plate, a liquid delivery motor support plate, a liquid delivery nut seat, a filter nozzle adapter, and a filter nozzle mounting plate.

[0012] The third lead screw stepper motor is mounted on the liquid delivery motor mounting plate. The second transverse lead screw is connected to the third lead screw stepper motor. The liquid delivery lifting cover plate is connected to the second transverse lead screw through the liquid delivery nut seat. The liquid delivery lifting motor is mounted on the liquid delivery motor lifting plate. The liquid delivery lifting cover plate is connected to the side of the liquid delivery motor lifting plate. The liquid delivery motor support plate is connected to the other end of the second transverse lead screw. The filter nozzle adapter is connected to the liquid delivery nut seat through the filter nozzle mounting plate.

[0013] As a preferred embodiment of the online ammonia nitrogen detection system in the production process of ternary precursors, the cuvette feeding assembly includes a vibration motor, a feeding tray, and a feeding channel; the vibration motor is connected to the lower part of the feeding tray, and the feeding channel is formed on the upper edge of the feeding tray.

[0014] As a preferred solution for the online ammonia nitrogen detection system in the production process of ternary precursors, the reaction cup / cubic dish transfer assembly includes a horizontal stepper motor, a vertical stepper motor, an adapter plate, a gripping and lifting motor, a horizontal drive block, a horizontal moving plate, a vertical drive block, a motor mounting base, a lifting transmission rod, a lifting drive block, and a reaction cup / cubic dish gripper.

[0015] The power output end of the horizontal stepper motor is connected to the horizontal drive block, the horizontal drive block is connected to the horizontal moving plate, the vertical stepper motor is mounted on the horizontal moving plate, and the power output end of the vertical stepper motor is engaged with the vertical drive block through a lead screw; the vertical drive block is connected to the motor mounting base through the adapter plate; the gripping lifting motor is mounted on the motor mounting base, the power output end of the gripping lifting motor is connected to the lifting transmission rod, the lifting transmission rod is connected to the lifting drive block, and the reaction cup / cubit gripper is fixedly connected to the lifting drive block.

[0016] This invention also provides an online ammonia nitrogen detection method during the production of ternary precursors, based on the above-mentioned online ammonia nitrogen detection system during the production of ternary precursors, comprising the following steps:

[0017] Step 1: Use a peristaltic pump to extract the precursor intermediate from the reaction vessel in the production process into the first beaker, and place the standard salicylic acid solution into the second beaker;

[0018] Step 2: The syringe pump of the sampling assembly draws the precursor intermediate from the first beaker, and the other syringe pump draws the standard salicylic acid solution from the second beaker.

[0019] Step 3: The syringe pump of the sampling component injects the set volume of precursor intermediate into the reaction vessel, and the other syringe pump of the sampling component slowly adds the set number of drops of standard salicylic acid solution. The reaction vessel is vibrated during the addition process, and the reaction is allowed to stand for a specified time after the reaction is complete.

[0020] Step 4: After the reaction vessel has been left to stand for a specified time, the supernatant is extracted by a peristaltic pump, filtered through a filter, and then injected into a cuvette of a set volume. The cuvette is then placed in a spectrophotometer for colorimetric analysis. The ammonia nitrogen concentration is obtained from the host computer by comparing the result with the standard curve.

[0021] Step 5: Discharge the precursor intermediate product from the first beaker. Use a peristaltic pump to draw water from a container containing clean water and purified water to clean the first beaker and the tubing from the peristaltic pump to the cuvette, in preparation for the next round of testing.

[0022] The method for online detection of ammonia nitrogen in the production process of ternary precursors according to claim 7 is characterized in that, in step three, the volume of the injected precursor intermediate product is 4.5 ml, injected all at once; the standard salicylic acid solution added is 0.45 ml, added in 10 portions, with vibration started simultaneously during the addition; after the addition is completed, mixing is performed, with air blowing started simultaneously during mixing; after mixing is completed, the mixture is allowed to stand and precipitate for 1 minute.

[0023] As a preferred method for online detection of ammonia nitrogen in the production process of ternary precursors, in step four, after the filtered supernatant is injected into a cuvette, it is placed in a spectrophotometer for 15 seconds and the detection result is recorded. After the detection is completed, the cuvette is rinsed with water, dried, and the next round of detection begins.

[0024] As a preferred method for online detection of ammonia nitrogen in the production process of ternary precursors, a standard curve is plotted based on the linear relationship between ammonia nitrogen concentration and absorption wavelength within a 5mm optical path range using salicylic acid spectrophotometry. The operation and running of the online ammonia nitrogen monitoring system are controlled by a PLC and a touch screen, and data is stored and managed, as well as remotely monitored, through a host computer.

[0025] The present invention has the following advantages: First, it eliminates the need to dilute high-concentration ammonia nitrogen samples and can directly measure high ammonia nitrogen concentrations of around 10 g / L. It can accurately obtain ammonia nitrogen values ​​during the production of ternary precursors, solving the problem of large deviations in the detection of high-concentration ammonia nitrogen in existing equipment.

[0026] Secondly, it achieves full automation from sampling to output of test results, requiring no manual intervention. It can run continuously and the cycle is adjustable, reducing errors caused by human operation, improving testing efficiency, and meeting the needs of high-frequency testing in industrial production.

[0027] Third, by adopting a PLC control system combined with equipment such as robotic arms, peristaltic pumps, and spectrophotometers, the system has achieved functions such as automatic continuous sampling, automatic titration reaction, automatic filtration, automatic detection, and automatic cleaning and replacement of reaction cups and cuvettes, thereby improving the system's integration and intelligence level.

[0028] Fourth, by utilizing volumetric metering pumps, lead screw and slider mechanisms, photoelectric switches, etc., the sampling, reaction, detection, and cleaning actions are coordinated, ensuring the stability and reliability of the detection process and providing accurate data support for process optimization (such as pH adjustment and determination of reaction termination timing).

[0029] Fifth, based on the salicylic acid spectrophotometry method at a 5mm optical path, a good linear relationship between the concentration of high-concentration ammonia nitrogen (8-10 mg / L) and the wavelength of light was achieved. The detection results can be obtained quickly by comparing with the standard curve, which improves the accuracy and timeliness of the detection. Attached Figure Description

[0030] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0031] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0032] Figure 1 This is a first-view perspective three-dimensional schematic diagram of the online ammonia nitrogen detection system in the ternary precursor production process provided in this embodiment of the invention.

[0033] Figure 2 This is a second-view perspective three-dimensional schematic diagram of the online ammonia nitrogen detection system in the ternary precursor production process provided in this embodiment of the invention.

[0034] Figure 3 This is a third-view perspective stereoscopic diagram of the online ammonia nitrogen detection system in the ternary precursor production process provided in this embodiment of the invention.

[0035] Figure 4 This is a fourth-view perspective stereoscopic diagram of the online ammonia nitrogen detection system in the ternary precursor production process provided in this embodiment of the invention.

[0036] Figure 5 This is a schematic diagram of the sampling component of the online ammonia nitrogen detection system provided in the ternary precursor production process according to an embodiment of the present invention.

[0037] Figure 6 This is a schematic diagram of the vibration reaction component of the online ammonia nitrogen detection system in the ternary precursor production process provided in this embodiment of the invention.

[0038] Figure 7 This is a schematic diagram of the reaction liquid extraction component of the online ammonia nitrogen detection system in the ternary precursor production process provided in this embodiment of the invention.

[0039] Figure 8 This is a schematic diagram of the cuvette feeding component of the online ammonia nitrogen detection system in the ternary precursor production process provided in this embodiment of the invention.

[0040] Figure 9This is a schematic diagram of the reaction cup / cube transfer assembly of the online ammonia nitrogen detection system in the ternary precursor production process provided in this embodiment of the invention.

[0041] Figure 10 The standard curves for ammonia concentration and absorbance at two different wavelengths are provided in this embodiment of the invention for the online detection method of ammonia nitrogen in the production process of ternary precursors.

[0042] Figure 11 The absorbance of the ammonia nitrogen online detection method in the ternary precursor production process provided in this embodiment of the invention is the absorbance at a wavelength of 630 nm within the ammonia concentration range of 1~15 g / L.

[0043] In the diagram, A is the sampling component; A1 is the first lead screw stepper motor; A2 is the liquid extraction lifting motor plate; A3 is the lifting nut seat; A4 is the liquid extraction lifting support plate; A5 is the liquid extraction pipeline plate; A6 is the syringe pump; A7 is the pump mounting base; and A8 is the injection needle.

[0044] B. Vibration response assembly; B1. Second lead screw stepper motor; B2. Nut connecting block; B3. First transverse lead screw; B4. Mixing transverse motor support plate; B5. Mixing beaker support plate; B6. Vibration motor mounting base; B7. First vibration motor; B8. Beaker bottom plate adapter; B9. Beaker body; B10. Beaker bottom plate;

[0045] C. Reaction liquid extraction assembly; C1. Third lead screw stepper motor; C2. Liquid delivery motor mounting plate; C3. Second transverse lead screw; C4. Liquid delivery lifting cover plate; C5. Liquid delivery lifting motor; C6. Liquid delivery motor lifting plate; C7. Liquid delivery motor support plate; C8. Liquid delivery nut seat; C9. Filter nozzle adapter; C10. Filter nozzle mounting plate;

[0046] D. Cuvette feeding assembly; D1. Second vibration motor; D2. Feeding tray; D3. Feeding channel;

[0047] E. Reaction cup / cubic cuvette transfer assembly; E1. Horizontal stepper motor; E2. Vertical stepper motor; E3. Adapter plate; E4. Gripping and lifting motor; E5. Horizontal drive block; E6. Horizontal moving plate; E7. Vertical drive block; E8. Motor mounting base; E9. Lifting transmission rod; E10. Lifting drive block; E11. Reaction cup / cubic cuvette gripper;

[0048] G. Fixing plate. Detailed Implementation

[0049] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] See Figure 1 , Figure 2 , Figure 3 and Figure 4 This invention provides an online ammonia nitrogen detection system for the production of ternary precursors, comprising a sampling component A, a vibration reaction component B, a reaction liquid extraction component C, a cuvette loading component D, a reaction cup / cuvette transfer component E, and a fixing plate G. The sampling component A, vibration reaction component B, reaction liquid extraction component C, cuvette loading component D, and reaction cup / cuvette transfer component E are all mounted on the fixing plate G. The sampling component A extracts the precursor intermediate and standard salicylic acid solution from the reaction vessel and injects them into the reaction cup. The vibration reaction component B carries the reaction cup and enables its vibration and position adjustment. The reaction liquid extraction component C extracts the reacted liquid from the vibration reaction component B and injects it into the cuvette. The cuvette loading component D provides the cuvettes. The reaction cup / cuvette transfer component E is used to grasp and replace the reaction cups / cuvettes.

[0051] Specifically, the online ammonia nitrogen detection system integrates sampling component A, vibration reaction component B, reaction liquid extraction component C, cuvette loading component D, and reaction cup / cuvette transfer component E onto a fixed plate G, forming a compact and collaborative whole to ensure the continuity of the detection process. Sampling component A is responsible for acquiring the precursor intermediate product to be detected and the standard salicylic acid solution required for the reaction, providing raw materials for subsequent reactions; vibration reaction component B promotes thorough mixing of reactants through vibration, while adjusting its position to cooperate with the operation of reaction liquid extraction component C and reaction cup / cuvette transfer component E; reaction liquid extraction component C transfers the reacted liquid to the cuvette for detection; cuvette loading component D provides clean cuvettes to ensure smooth detection; reaction cup / cuvette transfer component E realizes automatic replacement of reaction cups and cuvettes, avoiding the tediousness and contamination risk of manual operation. Each component has a clear division of labor and cooperates with each other to complete the entire process of online ammonia nitrogen detection.

[0052] See Figure 5In this embodiment, the sampling component A includes a first lead screw stepper motor A1, a liquid extraction lifting motor plate A2, a lifting nut seat A3, a liquid extraction lifting support plate A4, a liquid extraction pipeline plate A5, an injection pump A6, a pump mounting base A7, and an injection needle A8. The first lead screw stepper motor A1 is mounted on the liquid extraction lifting motor plate A2. The lifting nut seat A3 cooperates with the lead screw of the first lead screw stepper motor A1. The liquid extraction lifting support plate A4 is connected to the end of the lead screw of the first lead screw stepper motor A1. The liquid extraction pipeline plate A5 is connected to the side of the lifting nut seat A3. The injection pump A6 is mounted on the liquid extraction pipeline plate A5 through the pump mounting base A7. The injection needle A8 is connected to the injection pump A6.

[0053] Specifically, the first lead screw stepper motor A1 provides power for the movement of the sampling component A. Through the cooperation of the lead screw and the lifting nut seat A3, the rotational motion of the motor is converted into the linear motion of the lifting nut seat A3, which in turn drives the liquid collection pipeline plate A5 and the syringe pump A6 installed on it to move up and down. The liquid collection lifting support plate A4 supports the end of the lead screw, ensuring the stability of the lead screw's movement. As the core liquid collection component, the syringe pump A6 accurately draws the precursor intermediate product and standard salicylic acid solution from the corresponding container through the injection needle A8. The pump mounting base A7 ensures that the syringe pump A6 is firmly installed. The structural design of the entire component realizes precise positioning and quantitative aspiration of the sample, ensuring the accuracy of the sample volume.

[0054] See Figure 6 In this embodiment, the vibration response component B includes a second lead screw stepper motor B1, a nut connecting block B2, a first transverse lead screw B3, a mixing transverse motor support plate B4, a mixing beaker support plate B5, a vibration motor mounting base B6, a first vibration motor B7, a beaker bottom plate adapter B8, a beaker body B9, and a beaker bottom plate B10. The second lead screw stepper motor B1 is mounted on the mixing transverse motor support plate B4. The first transverse lead screw B3 is connected to the second lead screw stepper motor B1. The nut connecting block B2 cooperates with the first transverse lead screw B3. The mixing beaker support plate B5 is connected to the nut connecting block B2. The beaker bottom plate B10 is connected to the mixing beaker support plate B5 through the beaker bottom plate adapter B8. The vibration motor mounting base B6 is connected to the beaker bottom plate B10. The first vibration motor B7 is connected to the vibration motor mounting base B6. The beaker body B9 is placed in the beaker placement hole on the beaker bottom plate B10.

[0055] Specifically, the second lead screw stepper motor B1 drives the first lateral lead screw B3 to rotate, and the rotational motion is converted into the lateral movement of the mixing beaker support plate B5 through the nut connecting block B2. This causes the beaker bottom plate B10 and the beaker body B9 placed on it to move together, realizing the adjustment of the reaction cup position so as to cooperate with other components. The first vibration motor B7 transmits vibration to the beaker bottom plate B10 through the vibration motor mounting seat B6, which in turn causes the reactants in the beaker body B9 to vibrate, promoting the full mixing of the reactants and improving the reaction efficiency and uniformity. The beaker bottom plate adapter seat B8 connects and fixes the beaker bottom plate B10 to ensure that the vibration can be effectively transmitted, and the holes on the beaker bottom plate B10 play a positioning role for the beaker body B9 to prevent it from shifting during vibration and movement.

[0056] See Figure 7 In this embodiment, the reaction liquid extraction component C includes a third lead screw stepper motor C1, a liquid delivery motor mounting plate C2, a second transverse lead screw C3, a liquid delivery lifting cover plate C4, a liquid delivery lifting motor C5, a liquid delivery motor lifting plate C6, a liquid delivery motor support plate C7, a liquid delivery nut seat C8, a filter nozzle adapter C9, and a filter nozzle mounting plate C10. The third lead screw stepper motor C1 is mounted on the liquid delivery motor mounting plate C2. The second transverse lead screw C3 is connected to the third lead screw stepper motor C1. The liquid delivery lifting cover plate C4 is connected to the second transverse lead screw C3 through the liquid delivery nut seat C8. The liquid delivery lifting motor C5 is mounted on the liquid delivery motor lifting plate C6, and the liquid delivery lifting cover plate C4 is connected to the side of the liquid delivery motor lifting plate C6. The liquid delivery motor support plate C7 is connected to the other end of the second transverse lead screw C3. The filter nozzle adapter C9 is connected to the liquid delivery nut seat C8 through the filter nozzle mounting plate C10.

[0057] Specifically, the third lead screw stepper motor C1 drives the second transverse lead screw C3 to rotate. Through the cooperation of the liquid delivery nut seat C8 and the second transverse lead screw C3, components such as the liquid delivery lifting cover C4 move laterally. The liquid delivery motor support plate C7 supports the other end of the second transverse lead screw C3, ensuring its stable rotation. The liquid delivery lifting motor C5 provides power for the lifting and lowering of the liquid delivery components. Through the liquid delivery motor lifting plate C6, it drives the liquid delivery lifting cover C4 and other components to move up and down, adjusting the position of the filter nozzle adapter C9 so that it can accurately extract the reacted liquid from the reaction vessel. The filter nozzle adapter C9 is used to connect to a filtration device to filter the reacted liquid, remove impurities, ensure the purity of the liquid injected into the cuvette, and improve the accuracy of the detection results.

[0058] See Figure 8In this embodiment, the cuvette feeding assembly D includes a second vibration motor D1, a feeding tray D2, and a feeding channel D3; the second vibration motor D1 is connected to the lower part of the feeding tray D2, and the feeding channel D3 is formed on the upper edge of the feeding tray D2.

[0059] Specifically, when the second vibration motor D1 operates, it generates vibration, which drives the feeding tray D2 to vibrate. The cuvettes placed in the feeding tray D2 move orderly along the feeding channel D3 on the upper edge of the tray D2 under the action of vibration, achieving automatic feeding of the cuvettes. This vibration feeding method can efficiently transport the cuvettes to the designated position, providing clean cuvettes for the reaction solution extraction component C, ensuring the continuity of the detection process, and reducing the time and labor intensity of manual feeding.

[0060] See Figure 9 In this embodiment, the reaction cup / cubic cuvette transfer assembly E includes a horizontal stepper motor E1, a vertical stepper motor E2, an adapter plate E3, a gripping and lifting motor E4, a horizontal drive block E5, a horizontal moving plate E6, a vertical drive block E7, a motor mounting base E8, a lifting transmission rod E9, a lifting drive block E10, and a reaction cup / cubic cuvette gripper E11. The power output end of the horizontal stepper motor E1 is connected to the horizontal drive block E5, the horizontal drive block E5 is connected to the horizontal moving plate E6, and the vertical stepper motor E2 is mounted on the motor. Mounted on the transverse moving plate E6, the power output end of the longitudinal stepper motor E2 is connected to the longitudinal drive block E7 via a lead screw; the longitudinal drive block E7 is connected to the motor mounting base E8 via the adapter plate E3; the gripping lifting motor E4 is mounted on the motor mounting base E8, the power output end of the gripping lifting motor E4 is connected to the lifting transmission rod E9, the lifting transmission rod E9 is connected to the lifting drive block E10, and the reaction cup / cube gripper E11 is fixedly connected to the lifting drive block E10.

[0061] Specifically, the horizontal stepper motor E1 drives the horizontal moving plate E6 to move laterally via the horizontal drive block E5, achieving horizontal position adjustment of the entire assembly. The vertical stepper motor E2, mounted on the horizontal moving plate E6, drives the motor mounting base E8 and other components to move vertically via a lead screw and the vertical drive block E7, achieving vertical position adjustment. The gripping lifting motor E4 drives the reaction cup / cubic cuvette gripper E11 to move up and down via the lifting transmission rod E9 and the lifting drive block E10. Combined with the horizontal and vertical movements, the gripper accurately grasps the reaction cup or cuvette and transfers it to the designated position, enabling automatic replacement of reaction cups and cuvettes and ensuring container cleanliness and testing accuracy during the detection process.

[0062] The working process of the online ammonia nitrogen detection system in the ternary precursor production process of this invention is as follows:

[0063] I. System Initialization and Standby

[0064] After the system starts up, each component completes a reset and self-test in sequence, preparing for the testing process:

[0065] 11. Reaction cup / cubic cuvette transfer assembly E: The horizontal stepper motor E1, the vertical stepper motor E2, and the gripping and lifting motor E4 work together to precisely reset the reaction cup / cubic cuvette gripper E11 to the standby position. Real-time monitoring via photoelectric switches ensures that the gripper is unloaded and all motion axes return to zero, laying the foundation for subsequent gripping actions.

[0066] 12. Cuvette feeding assembly D: The second vibration motor D1 starts briefly, causing the feeding tray D2 to vibrate slightly, which prompts the cuvettes to return to their orderly positions in the feeding channel D3 at its upper edge, completing the preparation and waiting to supply cuvettes for the testing process.

[0067] 13. Sampling component A: The first lead screw stepper motor A1 drives the injection needle A8 to rise to the highest position, the injection pump A6 reverses to empty the internal residual liquid, and the needle reset is confirmed by the origin sensor to ensure the accuracy of the initial sampling state.

[0068] 14. Vibration reaction component B: The second lead screw stepper motor B1 drives the mixing beaker support plate B5 back to the initial position, the first vibration motor B7 is turned off, so that the beaker body B9 is precisely aligned with the sampling injection position, ready to receive the liquid sent by the sampling component.

[0069] 15. Reaction liquid extraction component C: The third lead screw stepper motor C1 drives the filter nozzle adapter C9 to rise to the high position, and the peristaltic pump reverses to empty the residue in the pipeline, which is in the state of waiting for extraction, to ensure the purity of the reaction liquid to be extracted later.

[0070] II. Precise Sampling

[0071] 21. Precursor and reagent extraction

[0072] Target positioning: The first lead screw stepper motor A1 of sampling component A rotates forward, driving the injection needle A8 to move downward. Combined with feedback from the liquid level sensor or preset coordinates, it accurately aligns with the first beaker containing the intermediate product of the precursor and the second beaker containing the standard salicylic acid solution, preparing for quantitative extraction.

[0073] Quantitative aspiration: The A6 syringe pump operates in volumetric metering mode, strictly controlling the extraction volume. Specifically, when extracting the precursor intermediate, a precise 4.5 mL is extracted in a single step to meet the subsequent "one-time injection" process requirement; when extracting the standard salicylic acid solution, it is performed in 10 separate 0.045 mL extractions, with the pump's pulse counting function ensuring the accuracy of each extraction, providing a basis for subsequent dropwise vibration mixing.

[0074] 22. Pour into the reaction vessel

[0075] Needle movement: The first lead screw stepper motor A1 reverses, driving the injection needle A8 to rise, and then moves laterally to above the beaker body B9 of the vibration reaction component B, ready to inject liquid.

[0076] Sequential injection: The syringe pump A6 is activated to inject the extracted precursor intermediate into the reaction vessel in one go; while the standard salicylic acid solution is injected slowly in 10 portions, with each injection spaced 1-2 seconds apart. Simultaneously, the first vibration motor B7 of the vibration reaction component B is triggered, causing it to operate in a high-frequency, low-amplitude vibration mode at a frequency of 30Hz and an amplitude of 2mm, allowing the liquids to mix synchronously during the droplet addition process and promoting uniform contact in the early stage of the reaction.

[0077] III. Vibration-induced reaction and static precipitation

[0078] 31. Dynamic Mixing Stage: The first vibration motor B7 continuously vibrates at a high frequency and low amplitude, in conjunction with any possible air blowing device, to create a vortex flow in the liquid within the reaction vessel, accelerating the colorimetric reaction between ammonia nitrogen and salicylic acid. After the addition is completed, the vibration motor does not immediately shut down but continues to run for 20-30 seconds (timed by PLC to ensure thorough mixing of the liquid), creating conditions for the full initiation of the reaction.

[0079] 32. Settling Stage: The first vibration motor B7 is de-energized, and the reaction vessel remains stationary along with the mixing beaker support plate B5. The system uses a PLC timer to time 1 minute, allowing the precipitate generated by the reaction to settle fully under gravity, making the supernatant clear liquid transparent, avoiding interference from the precipitate in the subsequent clear liquid extraction process, and ensuring the purity of the extracted liquid.

[0080] IV. Extraction and Detection of the Clear Liquid

[0081] 41. Precise extraction of clear liquid

[0082] Filter tip positioning: The third lead screw stepper motor C1 of the reaction liquid extraction component C rotates forward, driving the filter tip adapter C9 to move downward. Relying on the height sensor, it is precisely aligned with the supernatant layer of the reaction cup 2-3mm below the liquid surface, avoiding the sediment layer, in preparation for extracting the supernatant.

[0083] Filtration and extraction: The peristaltic pump rotates forward at a low flow rate of 5 mL / min to extract the supernatant from the reaction vessel. The supernatant flows through a microfilter with a built-in 0.45 μm filter membrane, effectively removing particulate impurities from the liquid and ensuring the purity of the liquid entering the cuvette, providing a reliable sample for subsequent spectral detection.

[0084] 42. Filling cuvettes

[0085] Cuvette positioning: The second vibration motor D1 of the cuvette feeding assembly D starts briefly to send the new cuvette to the filling position. The positioning sensor triggers the gripper E11 of the reaction cup / cuvette transfer assembly E to grab the cuvette, completing the feeding connection.

[0086] Clarified liquid injection: The peristaltic pump runs continuously, injecting the filtered clarified liquid into the cuvette until it reaches 80% of its volume. The injection volume is precisely controlled by a photoelectric level sensor or flow meter to prevent the clarified liquid from overflowing and ensure that the liquid level in the cuvette meets the detection requirements.

[0087] 43. Spectral Detection and Concentration Calculation

[0088] Cuvette transfer: The horizontal stepper motor E1 and the vertical stepper motor E2 of the reaction cup / cinnabar transfer assembly E work together to accurately deliver the cuvette filled with clear liquid to the spectrophotometer detection position. The mechanical positioning pins are used to achieve docking, ensuring the positional accuracy during detection.

[0089] Absorbance measurement: The spectrophotometer automatically switches to the preset optimal wavelength of 630nm to measure the absorbance of the liquid in the cuvette. The detection data is then uploaded to the host computer in real time.

[0090] Concentration conversion: The host computer calls a pre-stored "concentration-absorbance" fitting formula based on salicylic acid spectrophotometry. The mathematical expression is: ,in k, b To calibrate parameters, the ammonia nitrogen concentration is automatically calculated. The system displays and stores data in real time on the interface, providing a basis for production decisions.

[0091] V. Final Cycle

[0092] 51. Pipeline and container cleaning

[0093] Cleaning solution path: The peristaltic pump is switched to cleaning mode to draw clean water or purified water and rinse the first beaker in sequence to remove residual precursor materials and avoid cross-contamination. The sampling needle is rinsed with a combination of forward and back flushing to remove residues on the inner wall. The reaction cup is rinsed to prepare a clean container for the next reaction. The filter pipeline is also rinsed.

[0094] Cleaning verification: The conductivity of the cleaning fluid is detected in real time using a conductivity sensor. When the detected value is close to that of pure water, the cleaning is deemed qualified, the cleaning process ends, and preparations are made for the next round of testing.

[0095] 52. Consumable replacement shall be carried out as needed.

[0096] Reaction cup / cubic cuvette recycling: The reaction cup / cubic cuvette transfer component E's reaction cup / cubic cuvette gripper E11 grabs the used reaction cups and cuvettes and transfers them to the recycling area. It can be connected to an automatic recycling device to achieve orderly recycling of consumables.

[0097] New consumables replenishment: Cuvette feeding assembly D replenishes new cuvettes; if reaction cups need to be replaced, they are automatically replenished by the spare cup storage of vibration reaction assembly B or manually replenished to ensure the continuous supply of consumables for system operation.

[0098] This invention also provides an online ammonia nitrogen detection method during the production of ternary precursors, based on the aforementioned online ammonia nitrogen detection system for the production of ternary precursors, comprising the following steps:

[0099] Step 1: Using a peristaltic pump, extract the precursor intermediate from the reaction vessel in the production process into the first beaker, and place the standard salicylic acid solution into the second beaker. The peristaltic pump delivers the liquid by squeezing the tubing, which avoids contact between the liquid and the pump body, reducing the risk of contamination. This method is suitable for extracting precursor intermediates, a material used in industrial production. Placing the precursor intermediate and the standard salicylic acid solution in separate beakers facilitates subsequent sampling by the sampling components, preparing the raw materials for the reaction.

[0100] Step Two: The sampling assembly's syringe pump draws the precursor intermediate from the first beaker, while another syringe pump draws the standard salicylic acid solution from the second beaker. The syringe pumps possess high-precision quantitative aspiration capabilities; by drawing the precursor intermediate and standard salicylic acid solution separately, the two pumps can accurately control the aspiration volume of the two liquids, ensuring the accurate proportions of the materials required for the reaction. This lays the foundation for the thorough progress of the subsequent reaction and the accuracy of the detection results.

[0101] Step 3: The syringe pump of the sampling assembly injects a set volume of the precursor intermediate into the reaction vessel. Another syringe pump of the sampling assembly slowly adds a set number of drops of standard salicylic acid solution, vibrating the reaction vessel during the addition process. After the reaction is complete, allow it to stand for a specified time. The syringe pumps inject the precursor intermediate and standard salicylic acid solution into the reaction vessel according to the set volume, ensuring accurate amounts of reactants. The slow addition of the standard salicylic acid solution accompanied by vibration of the reaction vessel ensures thorough mixing of the two liquids, promoting uniform reaction and improving the reaction rate and completeness. Allowing the reaction to stand for a specified time after completion allows the reaction product to stabilize, preparing it for subsequent detection.

[0102] Step 4: After the reaction vessel has stood for the specified time, the supernatant is extracted by a peristaltic pump, filtered, and then injected into a cuvette of a predetermined volume. The cuvette is then placed in a spectrophotometer for colorimetric analysis. The ammonia nitrogen concentration is obtained from the analysis on a host computer by comparing the supernatant with a standard curve. Impurities in the reaction solution will precipitate after standing; extracting the supernatant reduces the impact of impurities on the detection results. The filter further filters out minute impurities in the supernatant, ensuring the purity of the liquid injected into the cuvette. The spectrophotometer utilizes the absorption characteristics of substances to different wavelengths of light to determine the ammonia nitrogen concentration through colorimetric analysis. By comparing the detection results with a pre-plotted standard curve, the ammonia nitrogen concentration value can be obtained quickly and accurately, and the results are displayed on a host computer, enabling real-time acquisition of the detection results.

[0103] Step 5: Discharge the precursor intermediate product from the first beaker. The peristaltic pump draws water from a container filled with clean water and purified water to rinse the first beaker and the tubing from the peristaltic pump to the cuvette, preparing for the next round of testing. Discharging the precursor intermediate product from the first beaker prevents residual material from affecting the next test. Rinsing the first beaker and related tubing with clean water removes residual material and reaction products, prevents cross-contamination, ensures the accuracy of the next round of testing, and enables the system to perform continuous and stable testing.

[0104] In this embodiment, in step three, the volume of the injected precursor intermediate is 4.5 ml, injected all at once; the standard salicylic acid solution is 0.45 ml, injected in 10 portions, with vibration activated during the addition; after the addition is complete, the mixture is stirred, with air blowing activated during the mixing; after mixing, the mixture is allowed to stand for 1 minute to settle.

[0105] Specifically, the injection and addition volumes—4.5 ml of the precursor intermediate and 0.45 ml of standard salicylic acid solution—are determined based on the stoichiometric relationship of the reaction and the required detection accuracy, ensuring the reaction proceeds fully and the detection signal is clear. Injecting the precursor intermediate all at once improves efficiency, while adding the standard salicylic acid solution in 10 drops with vibration facilitates better mixing of the two liquids. Aeration during mixing further promotes uniform mixing of the reactants and improves reaction efficiency. Allowing the mixture to settle for one minute allows the precipitate to settle fully, facilitating subsequent extraction of the supernatant for detection.

[0106] In this embodiment, in step four, after the filtered supernatant is injected into the cuvette, it is placed in the spectrophotometer for 15 seconds and the detection result is recorded. After the detection is completed, the cuvette is rinsed with water, dried, and the next round of detection begins.

[0107] Specifically, after injecting the filtered supernatant into the cuvette, it is placed in the spectrophotometer for 15 seconds. This allows the spectrophotometer sufficient time for light irradiation and signal acquisition, ensuring the stability and accuracy of the detection data. After the detection is completed, the cuvette is rinsed and dried to remove any residual detection liquid, preventing interference with subsequent detections and ensuring that each detection is performed in a clean environment.

[0108] In this embodiment, a standard curve is plotted based on the linear relationship between ammonia nitrogen concentration and absorption wavelength within a 5mm optical path range using salicylic acid spectrophotometry. The operation and running of the online ammonia nitrogen monitoring system are controlled by a PLC and a touch screen, and data is stored and managed, as well as remotely monitored, through a host computer.

[0109] Specifically, salicylic acid spectrophotometry is a mature method for ammonia nitrogen detection. Within a 5mm optical path length, ammonia nitrogen concentration exhibits a good linear relationship with the absorption wavelength, providing a theoretical basis for accurate colorimetric determination of ammonia nitrogen concentration. By plotting a standard curve using this linear relationship, the detected absorbance value can be quickly converted into an ammonia nitrogen concentration value. The PLC (Programmable Logic Controller) serves as the system's control core, controlling the coordinated operation of various components according to a preset program. A touchscreen provides a convenient operating interface for operators. The host computer is used for data storage and management, facilitating the analysis and traceability of historical test data, and enabling remote monitoring. This allows operators to understand the testing status remotely in real time, improving the system's intelligence and management efficiency.

[0110] See Figure 10 The figures show standard curves for ammonia concentration versus absorbance at two different wavelengths, with ammonia concentration on the horizontal axis and absorbance on the vertical axis. The two curves show a consistent trend: absorbance increases continuously with increasing ammonia concentration, demonstrating a strong linear relationship between ammonia concentration and absorbance; the higher the concentration, the stronger the absorption of light at a specific wavelength. Comparing 590nm and 630nm, the curve slopes and point distribution differ, reflecting the difference in sensitivity for ammonia nitrogen detection at different wavelengths. Therefore, 630nm is more suitable for detecting high concentrations of 1-15 g / L.

[0111] See Figure 11The absorbance values ​​at a wavelength of 630 nm represent the ammonia concentration range of 1–15 g / L. The horizontal axis represents ammonia concentration (1–15 g / L), and the vertical axis represents absorbance, covering the typical range for "high ammonia nitrogen detection" in industrial production. The data points (orange dots) highly coincide with the fitted line (blue dashed line), indicating that the absorbance linearity for high concentrations of ammonia nitrogen (1–15 g / L) at 630 nm is excellent (R² close to 1). This demonstrates that high-concentration samples do not require dilution in production; they can be directly detected at 630 nm. Through the conversion of absorbance, standard curve, and ammonia concentration, results can be obtained quickly and accurately, solving the problem of large deviations in high-concentration detection using traditional methods. This invention's ammonia nitrogen detection method can accurately cover the high ammonia nitrogen detection needs of production scenarios at a wavelength of 630 nm, providing a reliable basis for process optimization and quality control.

[0112] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. An ammonia nitrogen on-line detection system in a ternary precursor production process, characterized in that, It includes a sampling assembly (A), a vibration reaction assembly (B), a reaction liquid extraction assembly (C), a cuvette loading assembly (D), a reaction cup / cuvette transfer assembly (E), and a fixing plate (G). The sampling assembly (A), the vibration reaction assembly (B), the reaction liquid extraction assembly (C), the cuvette loading assembly (D), and the reaction cup / cuvette transfer assembly (E) are all mounted on a fixed plate (G). The sampling assembly (A) extracts the precursor intermediate and standard salicylic acid solution from the reaction vessel and injects them into the reaction cup. The vibration reaction assembly (B) carries the reaction cup and enables its vibration and position adjustment. The reaction liquid extraction assembly (C) extracts the reacted liquid from the vibration reaction assembly (B) and injects it into the cuvette. The cuvette loading assembly (D) provides the cuvettes. The reaction cup / cuvette transfer assembly (E) is used to pick up and replace the reaction cups / cuvettes. The sampling assembly (A) includes a first lead screw stepper motor (A1), a liquid extraction lifting motor plate (A2), a lifting nut seat (A3), a liquid extraction lifting support plate (A4), a liquid extraction pipeline plate (A5), an injection pump (A6), a pump mounting base (A7), and an injection needle (A8). The first lead screw stepper motor (A1) is mounted on the liquid dispensing lifting motor plate (A2), the lifting nut seat (A3) is engaged with the lead screw of the first lead screw stepper motor (A1), the liquid dispensing lifting support plate (A4) is connected to the end of the lead screw of the first lead screw stepper motor (A1), the liquid dispensing pipeline plate (A5) is connected to the side of the lifting nut seat (A3), the injection pump (A6) is mounted on the liquid dispensing pipeline plate (A5) through the pump fixing seat (A7), and the injection needle (A8) is connected to the injection pump (A6). The vibration response assembly (B) includes a second lead screw stepper motor (B1), a nut connecting block (B2), a first transverse lead screw (B3), a hybrid transverse motor support plate (B4), a hybrid beaker support plate (B5), a vibration motor mounting base (B6), a first vibration motor (B7), a beaker bottom plate adapter (B8), a beaker body (B9), and a beaker bottom plate (B10). The second lead screw stepper motor (B1) is mounted on the hybrid transverse motor support plate (B4). The first transverse lead screw (B3) is connected to the second lead screw stepper motor (B1). The nut connecting block (B2) cooperates with the first transverse lead screw (B3). The hybrid beaker support plate (B5) is connected to the nut connecting block (B2). The beaker bottom plate (B10) is connected to the hybrid beaker support plate (B5) through the beaker bottom plate adapter (B8). The vibration motor mounting base (B6) is connected to the beaker bottom plate (B10). The first vibration motor (B7) is connected to the vibration motor mounting base (B6). The beaker body (B9) is placed in the beaker placement hole on the beaker bottom plate (B10). The reaction cup / cubic cuvette transfer assembly (E) includes a horizontal stepper motor (E1), a vertical stepper motor (E2), an adapter plate (E3), a gripping and lifting motor (E4), a horizontal drive block (E5), a horizontal moving plate (E6), a vertical drive block (E7), a motor mounting base (E8), a lifting transmission rod (E9), a lifting drive block (E10), and a reaction cup / cubic cuvette gripper (E11). The power output end of the horizontal stepper motor (E1) is connected to the horizontal drive block (E5), the horizontal drive block (E5) is connected to the horizontal moving plate (E6), the vertical stepper motor (E2) is mounted on the horizontal moving plate (E6), and the power output end of the vertical stepper motor (E2) is connected to the vertical drive block (E7) via a lead screw; the vertical drive block (E7) is connected to the motor mounting base (E8) via the adapter plate (E3); the gripping lifting motor (E4) is mounted on the motor mounting base (E8), the power output end of the gripping lifting motor (E4) is connected to the lifting transmission rod (E9), the lifting transmission rod (E9) is connected to the lifting drive block (E10), and the reaction cup / cube gripper (E11) is fixedly connected to the lifting drive block (E10). 2.The ammonia nitrogen on-line detection system in a three-element precursor production process according to claim 1, characterized in that, The reaction liquid extraction assembly (C) includes a third lead screw stepper motor (C1), a liquid delivery motor mounting plate (C2), a second transverse lead screw (C3), a liquid delivery lifting cover plate (C4), a liquid delivery lifting motor (C5), a liquid delivery motor lifting plate (C6), a liquid delivery motor support plate (C7), a liquid delivery nut seat (C8), a filter nozzle adapter (C9), and a filter nozzle mounting plate (C10). The third lead screw stepper motor (C1) is mounted on the liquid delivery motor mounting plate (C2). The second transverse lead screw (C3) is connected to the third lead screw stepper motor (C1). The liquid delivery lifting cover plate (C4) is connected to the second transverse lead screw (C3) through the liquid delivery nut seat (C8). The liquid delivery lifting motor (C5) is mounted on the liquid delivery motor lifting plate (C6). The liquid delivery lifting cover plate (C4) is connected to the side of the liquid delivery motor lifting plate (C6). The liquid delivery motor support plate (C7) is connected to the other end of the second transverse lead screw (C3). The filter nozzle adapter (C9) is connected to the liquid delivery nut seat (C8) through the filter nozzle mounting plate (C10). 3.The ammonia nitrogen on-line detection system in a ternary precursor production process according to claim 1, characterized in that, The cuvette feeding assembly (D) includes a second vibration motor (D1), a feeding tray (D2), and a feeding channel (D3); the second vibration motor (D1) is connected to the lower part of the feeding tray (D2), and the feeding channel (D3) is formed on the upper edge of the feeding tray (D2).

4. An ammonia nitrogen online detection method in a ternary precursor production process, characterized in that, The online ammonia nitrogen detection system for the ternary precursor production process according to any one of claims 1-3 includes the following steps: Step 1: Use a peristaltic pump to extract the precursor intermediate from the reaction vessel in the production process into the first beaker, and place the standard salicylic acid solution into the second beaker; Step 2: The syringe pump of the sampling assembly draws the precursor intermediate from the first beaker, and the other syringe pump draws the standard salicylic acid solution from the second beaker. Step 3: The syringe pump of the sampling component injects the set volume of precursor intermediate into the reaction vessel, and the other syringe pump of the sampling component slowly adds the set number of drops of standard salicylic acid solution. The reaction vessel is vibrated during the addition process, and the reaction is allowed to stand for a specified time after the reaction is complete. Step 4: After the reaction vessel has been left to stand for a specified time, the supernatant is extracted by a peristaltic pump, filtered through a filter, and then injected into a cuvette of a set volume. The cuvette is then placed in a spectrophotometer for colorimetric analysis. The ammonia nitrogen concentration is obtained from the host computer by comparing the result with the standard curve. Step 5: Discharge the precursor intermediate product from the first beaker. Use a peristaltic pump to draw water from a container containing clean water and purified water to clean the first beaker and the tubing from the peristaltic pump to the cuvette, in preparation for the next round of testing.

5. The method according to claim 4, wherein the ammonia nitrogen is measured on-line during the production of the ternary precursor. In step three, the volume of the injected precursor intermediate is 4.5 ml, injected all at once; the standard salicylic acid solution is 0.45 ml, injected in 10 portions, with vibration activated during the addition; after the addition is complete, the mixture is stirred while blowing air; after mixing, the mixture is allowed to stand for 1 minute to settle.

6. The method according to claim 4, wherein the ammonia nitrogen is detected on line during the production of the ternary precursor. In step four, after the filtered supernatant is poured into the cuvette, it is placed in the spectrophotometer for 15 seconds and the detection result is recorded. After the detection is completed, the cuvette is rinsed with water, dried, and the next round of detection begins.

7. The method for online detection of ammonia nitrogen in the production process of ternary precursors according to claim 4, characterized in that, Based on the salicylic acid spectrophotometric method within a 5mm optical path range, a standard curve is plotted using the linear relationship between ammonia nitrogen concentration and absorption wavelength. The operation and running of the online ammonia nitrogen monitoring system are controlled by a PLC and a touch screen, and data storage and management, as well as remote monitoring, are achieved through a host computer.

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