An acid precipitation method-based fulvic acid extraction system

Abstract

The application relates to a fulvic acid extraction system based on an acid precipitation method, which comprises a mixing container and an acid adjusting assembly, the acid adjusting assembly comprises a dropper, an infusion pump and a liquid storage tank, one end of the dropper is inserted into the mixing container, the other end is connected with a liquid outlet of the infusion pump, a suction tube is arranged in the liquid storage tank, one end of the suction tube is connected with a liquid inlet of the infusion pump; a pH detector probe is arranged in the mixing container, the pH detector probe is electrically connected with a pH detector, the infusion pump can drop the pH adjusting liquid stored in the liquid storage tank into the mixing container drop by drop through the dropper to mix with the solution containing fulvic acid, so that the pH of the solution is gradually reduced, and the problem that the structure of the fulvic acid is damaged due to excessive local acidity of the solution caused by too fast titration speed during artificial titration is avoided; the pH detector probe can monitor the pH of the solution in real time, and can prevent the structure of the fulvic acid from being damaged due to excessive addition of the pH adjusting liquid.

Description

Technical Field

[0001] This application belongs to the field of fulvic acid detection technology, and specifically relates to a fulvic acid extraction system based on acid precipitation. Background Technology

[0002] Fulvic acid, a type of humic acid, possesses strong soil-amortizing and metal-chelating abilities. Therefore, it is often used as a soil conditioner in combination with water-soluble fertilizers such as potassium and phosphate fertilizers. However, fulvic acid is relatively expensive. To prevent unscrupulous merchants from adding other impurities or inefficient substitutes to fulvic acid fertilizers, it is necessary to accurately test the fulvic acid content in the fertilizer. Therefore, purifying fulvic acid is one of the key steps before testing. In existing technologies, alkali extraction and acid precipitation are commonly used to extract fulvic acid from fulvic acid water-soluble fertilizer solutions. After adding alkaline fulvic acid extract to the test solution and separating the layers, acidic pH adjustment solution needs to be added dropwise to the supernatant containing fulvic acid to precipitate the fulvic acid and achieve "acid precipitation". However, during the "acid precipitation" process, the operator needs to hold a dropper or funnel to add acidic pH adjustment solution to the supernatant to lower the pH value of the supernatant to 1±0.1. This process is not only labor-intensive, but also difficult to control the drip rate and titration amount. It is very easy to cause over-acidification, which will destroy the fulvic acid structure and thus affect the accuracy of subsequent fulvic acid content determination. Summary of the Invention

[0003] Based on the aforementioned technical needs, this application provides a fulvic acid extraction system based on acid precipitation, which allows operators to easily control the dripping rate and titration amount of the acidic pH adjustment solution during the fulvic acid extraction process, thereby improving the accuracy of fulvic acid content determination.

[0004] To achieve the above objectives, the technical solution of this application is as follows: A fulvic acid extraction system based on acid precipitation includes a mixing container and an acidity adjustment component. The acidity adjustment component includes a dropper, an infusion pump, and a storage tank. One end of the dropper extends into the mixing container, and the other end is connected to the outlet of the infusion pump. A suction tube is installed in the storage tank, and one end of the suction tube is connected to the inlet of the infusion pump. A pH meter probe is installed in the mixing container, and the pH meter probe is electrically connected to a pH meter.

[0005] Preferably, the dropper includes a main tube and at least one capillary branch tube. One end of the main tube is connected to the outlet of the infusion pump, and one end of the capillary branch tube is connected to the side of the main tube. Flow regulating valves are provided on the main tube below the capillary branch tube and on the capillary branch tube.

[0006] Preferably, the infusion pump is a peristaltic pump.

[0007] Preferably, the fulvic acid extraction system based on acid precipitation further includes a mixing component, at least a portion of which is located within the mixing container, and the mixing component is used to agitate the liquid within the mixing container.

[0008] Preferably, the mixing assembly includes a base, a magnetic stirring motor, and a magnetic rotor. The upper surface of the base is a plane for horizontally placing the mixing container. The magnetic stirring motor is located below the upper surface of the base and has a magnet on its output shaft. The magnetic rotor is located inside the mixing container.

[0009] Preferably, the upper surface of the base is provided with a plurality of limiting portions around the circumference of the mixing container, the limiting portions being used to prevent the mixing container from sliding relative to the upper surface of the base.

[0010] Preferably, the upper surface of the base is provided with a plurality of heating plates around the circumference of the mixing container, the heating plates being used to heat the liquid inside the mixing container.

[0011] Preferably, a support arm is provided on one side of the base in a vertical direction, and a fixed seat is provided on the support arm above the mixing container. A lifting drive assembly is provided on the fixed seat, and the pH value detector probe is driven to move along the axial direction of the mixing container.

[0012] Preferably, the fixing base has a through hole in the vertical direction, and a limiting wall is provided adjacent to the through hole. The lifting drive assembly includes several pairs of limiting rollers and a drive motor. The several pairs of limiting rollers are spaced apart along the axial direction of the through hole on one side of the limiting wall, and any pair of limiting rollers is symmetrically distributed with respect to the axial direction of the through hole. A limiting groove is provided on the rolling surface of the limiting roller. The pH value detector probe passes through the through hole and fits with the limiting groove. The drive shaft of the drive motor is connected to any one of the limiting rollers.

[0013] By adopting the above technical solution, compared with the prior art, this application has at least the following beneficial effects: The infusion pump can drip the pH adjusting solution stored in the storage tank into the mixing container through the dropper to mix with the solution containing fulvic acid, thereby gradually reducing the pH value of the solution and avoiding local over-acidity caused by excessively fast titration during manual titration, which could damage the fulvic acid structure. The pH value detector probe can monitor the pH value of the solution in real time, preventing excessive addition of pH adjusting solution that could damage the fulvic acid structure. Attached Figure Description

[0014] Figure 1This is a schematic diagram of the fulvic acid extraction system in the embodiment.

[0015] Figure 2 This is a partial top view of the fulvic acid extraction system in the embodiment.

[0016] Figure 3 This is a partially enlarged view of the fulvic acid extraction system in the example (from...). Figure 1 ).

[0017] In the diagram: mixing container 10, acidity adjustment component 20, dropper 21, main pipe 211, capillary branch pipe 212, flow regulating valve 213, infusion pump 22, storage tank 23, pipette 24, pH meter 30, pH meter probe 31, mixing component 40, base 41, limiting part 411, magnetic stirring motor 42, magnetic rotor 43, magnet 44, heating plate 45, support arm 46, fixed base 47, through hole 471, limiting wall 472, lifting drive component 50, limiting roller 51, limiting groove 511, drive motor 52. Detailed Implementation

[0018] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of this application will be further described below with reference to the accompanying drawings of the embodiments, and this application is not limited to the following specific implementation methods.

[0019] It should be understood that the same or similar reference numerals in the accompanying drawings of the embodiments correspond to the same or similar components. In the description of this application, it should be understood that if terms such as "upper," "lower," "inner," "outer," "left," "right," "front," "rear," "top," and "bottom" indicate directions or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the structure or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms describing positional relationships in the accompanying drawings are for illustrative purposes only and should not be construed as limitations on this patent. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0020] The following is in conjunction with the appendix Figure 1 To be continued Figure 3 The present application will be further described in detail with reference to specific embodiments.

[0021] This application discloses a fulvic acid extraction system based on acid precipitation (hereinafter referred to as the "system"). The system includes a mixing container 10 and an acidity adjustment component 20. The mixing container 10 is a cylindrical liquid container with a flat bottom, providing space for mixing an acidic pH adjustment solution and a solution containing fulvic acid. The acidity adjustment component 20 includes a dropper 21, an infusion pump 22, and a storage tank 23. One end of the dropper 21 extends above the liquid surface in the mixing container 10, and the other end is connected to the outlet of the infusion pump 22. The storage tank 23 is used to store the acidic pH adjustment solution, and a pipette 24 is provided inside the storage tank 23. One end of the pipette 24 is connected to the inlet of the infusion pump 22, and the infusion pump 22 can pump the pH adjustment solution in the storage tank 23 into the dropper 21 through the pipette 24 at a set flow rate. The pH adjusting solution is injected dropwise into the mixing container 10 via pipette 21. Pipe 21 limits the amount of pH adjusting solution that can be injected per unit time, preventing the solution from being injected directly into the mixing container 10 in a stream or column. This is to prevent excessive acidification of the solution due to excessive pH adjusting solution injection, which could damage the fulvic acid structure. To prevent excessive addition of pH adjusting solution from causing the pH of the mixture to be too low and damaging the fulvic acid structure, a pH meter probe 31 is also installed in the mixing container 10. The pH meter probe 31 is electrically connected to a pH meter 30. The pH meter 30 can output the pH value of the solution in real time via the pH meter probe 31 until the pH value of the solution reaches 1±0.1, so as to prompt the operator to stop adding pH adjusting solution to the mixing container 10.

[0022] In summary, the above-mentioned acid precipitation-based fulvic acid extraction system has the following beneficial effects: The infusion pump 22 can drip the pH adjustment solution stored in the storage tank 23 into the mixing container 10 through the dropper 21 to mix with the solution containing fulvic acid, thereby achieving the purpose of gradually reducing the pH value of the solution and avoiding local over-acidity of the solution due to excessively fast titration during manual titration, which would damage the structure of fulvic acid. The pH value detector probe 31 can monitor the pH value of the solution in real time, which can prevent the addition of excessive pH adjustment solution from damaging the structure of fulvic acid.

[0023] In addition, this application provides some specific embodiments to improve the above system.

[0024] Furthermore, to improve the efficiency of reducing the pH of the fulvic acid solution by using large droplets and continuous titration in the initial stage of titration, and to achieve fine-tuning of the pH of the fulvic acid solution by using small droplets and intermittent titration in the later stage of titration, the dropper 21 includes a main pipe 211 and capillary branches 212. One end of the main pipe 211 is connected to the outlet of the infusion pump 22, and one end of the capillary branches 212 is connected to the side of the main pipe 211, with the other end branching out in a direction deviating from the radial direction of the main pipe 211. Flow regulating valves 213 are installed on both the main pipe 211 below the connection point of the capillary branches 212 and on the capillary branches 212. Specifically, the number of capillary branches 212 is at least one, and may be more than one if necessary. In one specific embodiment, a first capillary branch 212 and a second capillary branch 212 are provided on the main pipe 211. The titration process is divided into an early stage, a transition stage, and a late stage. The pH value of the solution is controlled within the range of the initial pH value to 3.0, 3.0 to 2.0, and 2.0 to 1.0 in the three stages, respectively. The droplet diameters in the three stages are 2.0 to 3.0 mm, 1.5 to 2.0 mm, and 0.5 to 1.5 mm, respectively. The flow rates in the three stages are 1.0 to 2.0 ml / min, 0.5 to 1.0 ml / min, and 0.1 to 0. The flow rate is 5 ml / min. The inner diameter of the main pipe 211 is preferably 2.5 mm (the median of the droplet diameter in the early stage), and the flow regulating valve 213 installed on it can adjust the maximum flow rate to 2.0 ml / min. The inner diameter of the first capillary branch 212 is preferably 1.75 mm, and the flow regulating valve 213 installed on it can adjust the maximum flow rate to 1.0 ml / min. The inner diameter of the second capillary branch 212 is preferably 1 mm, and the flow regulating valve 213 installed on it can adjust the maximum flow rate to 0.5 ml / min.

[0025] When using the above system, the titration flow rate and droplet size can be adjusted by sequentially closing and opening the flow regulating valve 213 on the main pipe 211 or capillary branch pipe 212 during different titration processes (early stage, transition stage, and late stage).

[0026] In a preferred embodiment, to relatively slow down the titration rate and assist the dropper 21 in forming drops, the infusion pump 22 is a peristaltic pump to facilitate the formation of a stable pulsating flow, thereby controlling the titration rate. Furthermore, the peristaltic pump can also be electrically connected to the pH meter 30. In a pre-set program, the rotational speed of the peristaltic pump is matched to the reading of the pH meter 30, allowing the peristaltic pump to automatically switch its rotational speed based on the pH value of the solution at different titration stages, achieving the purpose of automatically adjusting the rotational speed and flow rate.

[0027] To improve the mixing effect of pH adjustment solution and fulvic acid solution, the system further includes a mixing component 40, at least a portion of which is disposed inside the mixing container 10 so as to directly contact the solution and agitate the liquid inside the mixing container 10.

[0028] Specifically, the mixing assembly 40 includes a base 41, a magnetic stirring motor 42, and a magnetic rotor 43. The upper surface of the base 41 is flat, used to horizontally place the mixing container 10. A mounting hole is provided on the upper surface of the base 41, and the magnetic stirring motor 42 is installed below the upper surface of the base 41 within the mounting hole. A magnet 44 is mounted on the output shaft of the magnetic stirring motor 42, and the magnetic rotor 43 is placed inside the mixing container 10. After the magnetic stirring motor 42 is started, the output shaft drives the magnet 44 to rotate, generating a rotating magnetic field. This causes the magnetic rotor 43 to stir the solution inside the mixing container 10 under the influence of the magnetic field, thereby increasing the mixing efficiency of the pH adjusting solution and the humic acid solution and improving the uniformity of the solution.

[0029] Furthermore, the upper surface of the base 41 is provided with a plurality of limiting parts 411 around the circumference of the mixing container. In one embodiment, the bottom of the limiting part 411 is slidably connected to the base 41 through a sliding groove provided on the upper surface of the base 41. The upper part of the base 41 is in the shape of a claw. The plurality of limiting parts 411 can slide toward the bottom of the mixing container and limit the mixing container 10 after stopping, so as to prevent the mixing container from shifting during the disturbance of the liquid.

[0030] To further improve the mixing effect of the fulvic acid solution and the pH adjustment solution, a plurality of heating plates 45 are arranged circumferentially on the surface of the base 41 surrounding the mixing container 10. The heating plates 45 are preferably electric heating plates, which generate heat when energized to heat the solution. Heating the solution within the range of 25°C to 50°C can accelerate the mixing speed of the two liquids and shorten the pH equilibrium time. The heating plates 45 can work in conjunction with the mixing component 40 to heat and stir the solution simultaneously, avoiding local over-acidity or overheating of the solution, thus preventing damage to the fulvic acid structure due to overheating or over-acidity.

[0031] Based on the above embodiments, to prevent local imbalance during the pH adjustment process, a support arm 46 is vertically arranged on one side of the base 41. A fixed seat 47 is movably arranged on the support arm 46 above the mixing container 10. A lifting drive assembly 50 is arranged on the fixed seat 47, and the pH meter probe 31 is driven by the lifting drive assembly 50. After adjusting the position of the fixed seat 47 relative to the support arm 46 so that it is directly above the mixing container 10, the pH meter probe 31 is driven by the lifting drive assembly 50 to move along the axial direction of the mixing container 10 within the liquid level height range. This allows the pH meter probe 31 to detect the pH of the mixed liquid at various heights in the mixing container 10. During the detection process, the titration speed and stirring degree are controlled to adjust the pH of the mixed solution and prevent local over-acidity imbalance.

[0032] In one embodiment, the aforementioned fixing base 47 has a through hole 471 in the vertical direction for the pH meter probe 31 to pass through, and a limiting wall 472 is provided on the side of the fixing base 47 adjacent to the through hole 471. The aforementioned lifting drive assembly 50 includes several pairs of limiting rollers 51 and a drive motor 52. The several pairs of limiting rollers 51 are spaced apart along the axial direction of the through hole 471 on the side of the limiting wall 472 adjacent to the through hole 471, and any pair of limiting rollers 51 are symmetrically distributed along the axial direction of the through hole 471. The roller surface of the limiting roller 51 is provided with a limiting groove 511 for fitting with the side of the pH meter probe 31, and the drive shaft of the drive motor 52 is connected to any one of the limiting rollers 51. Specifically, in this embodiment, two pairs of limiting rollers 51 are arranged vertically on the limiting wall 472. The pH value detector probe 31 passes through the through hole 471 axially downwards and its side is sandwiched between the limiting grooves 511 of the two pairs of limiting rollers 51. The drive motor 52 is a servo motor. When its output shaft rotates around the first direction, it drives the limiting rollers 51 to generate a downward frictional force on the pH value detector probe 31. The other limiting rollers 51 restrict the movement direction of the pH value detector probe 31 and guide the pH value detector probe 31 to move downwards, thereby driving the pH value detector probe 31 to move downwards to detect the pH value at a deeper depth in the mixture. When the output shaft rotates in the opposite direction around the first direction, the limiting rollers 51 drive the pH value detector probe 31 to move upwards. This allows the pH value detector 30 to easily and automatically monitor the pH value at various depths of the mixture, preventing the mixture from becoming locally overly acidic or unbalanced.

[0033] When using the above system, the titration flow rate can be adjusted by regulating the flow regulating valve 213 or the speed of the peristaltic pump on the main pipe 211 or capillary branch pipe 212. By sequentially switching the connection between the main pipe 211 or capillary branch pipe 212 and the infusion pump 22, the size of the titration droplet can be adjusted during the titration process. During the titration process, the mixing effect and efficiency are improved by the mixing component 40 and the heating block. Throughout the titration process (especially in the later stage), the height of the pH value detector probe 31 in the mixed solution is adjusted by the lifting drive component 50 to monitor the pH value at each liquid level of the mixed solution, preventing local over-acidity or mixing imbalance from affecting the structural integrity of fulvic acid.

[0034] Obviously, the above embodiments of this application are merely examples for clearly illustrating this application, and are not intended to limit the implementation of this application. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A fulvic acid extraction system based on acid precipitation, characterized in that, The device includes a mixing container and an acidity adjustment assembly. The acidity adjustment assembly includes a dropper, an infusion pump, and a storage tank. One end of the dropper extends into the mixing container, and the other end is connected to the outlet of the infusion pump. A pipette is installed in the storage tank, and one end of the pipette is connected to the inlet of the infusion pump. A pH meter probe is installed in the mixing container, and the pH meter probe is electrically connected to a pH meter.

2. The fulvic acid extraction system based on acid precipitation as described in claim 1, characterized in that, The dropper includes a main tube and at least one capillary branch tube. One end of the main tube is connected to the outlet of the infusion pump, and one end of the capillary branch tube is connected to the side of the main tube. Flow regulating valves are provided on the main tube below the capillary branch tube and on the capillary branch tube.

3. The fulvic acid extraction system based on acid precipitation as described in claim 1, characterized in that, The infusion pump is a peristaltic pump.

4. The fulvic acid extraction system based on acid precipitation as described in claim 1, characterized in that, It also includes a mixing component, at least a portion of which is located within the mixing container, the mixing component being used to agitate the liquid within the mixing container.

5. The fulvic acid extraction system based on acid precipitation as described in claim 4, characterized in that, The mixing assembly includes a base, a magnetic stirring motor, and a magnetic rotor. The upper surface of the base is a plane for horizontally placing the mixing container. The magnetic stirring motor is located below the upper surface of the base and has a magnet on its output shaft. The magnetic rotor is located inside the mixing container.

6. The fulvic acid extraction system based on acid precipitation as described in claim 5, characterized in that, The upper surface of the base is provided with a plurality of limiting parts around the circumference of the mixing container, the limiting parts being used to prevent the mixing container from sliding relative to the upper surface of the base.

7. The fulvic acid extraction system based on acid precipitation as described in claim 5, characterized in that, The upper surface of the base is provided with a plurality of heating plates around the circumference of the mixing container, and the heating plates are used to heat the liquid in the mixing container.

8. The fulvic acid extraction system based on acid precipitation as described in any one of claims 5 to 7, characterized in that, A support arm is provided on one side of the base in a vertical direction. A fixed seat is provided on the support arm above the mixing container. A lifting drive assembly is provided on the fixed seat. The pH value detector probe is driven by the lifting drive assembly. The lifting drive assembly is used to drive the pH value detector probe to move along the axial direction of the mixing container.

9. The fulvic acid extraction system based on acid precipitation as described in claim 8, characterized in that, The fixed base has a through hole in the vertical direction, and a limiting wall is provided adjacent to the through hole. The lifting drive assembly includes several pairs of limiting rollers and a drive motor. The several pairs of limiting rollers are spaced apart along the axial direction of the through hole on one side of the limiting wall, and any pair of limiting rollers is symmetrically distributed with respect to the axial direction of the through hole. A limiting groove is provided on the rolling surface of the limiting roller. The pH value detector probe passes through the through hole and fits with the limiting groove. The drive shaft of the drive motor is connected to any one of the limiting rollers.

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