A quantitative acid addition instrument

Abstract

This utility model discloses a quantitative acid addition instrument, including a platform scale. An acid addition pump electrically connected to one side of the platform scale is provided. A switch on the platform scale controls the on / off state of the acid addition pump. The switch is configured to automatically shut off the acid addition pump when the weighing weight on the platform scale reaches a preset weight threshold. The inlet of the acid addition pump is connected to an acid storage bottle via an inlet pipe. An adjusting column is provided on the platform scale, and a support portion extending above the weighing surface of the platform scale is provided on the adjusting column. A guide hole is provided on the support portion. A addition pipe is connected to the outlet of the acid addition pump, and the addition pipe passes through the guide hole with its end suspended above the weighing surface. This utility model enables quantitative acid addition, effectively improving the accuracy and efficiency of acid addition, reducing manpower consumption, and eliminating the need for frequent opening of the acid reagent storage container. This avoids burns or inhalation of toxic gases when opening the acid reagent storage container, thus improving the safety of acid addition.

Description

Technical Field

[0001] This utility model relates to the field of experimental instrument technology, specifically to a quantitative acid addition instrument. Background Technology

[0002] In laboratory work across many fields, including environmental monitoring, food safety, geological analysis, and biomedicine, chemical digestion is a crucial step in sample pretreatment. Its purpose is to use strong acids under heating conditions to break down the sample matrix, converting target elements into measurable ionic forms. This process requires the precise injection of highly corrosive liquids such as concentrated nitric acid or concentrated hydrochloric acid into the sample to achieve an oxidation reaction under high-temperature conditions.

[0003] Currently, laboratories generally rely on manual pipetting. Researchers must use pipettes, tubes, or graduated cylinders to aspirate and quantitatively transfer highly corrosive, volatile, and potentially toxic concentrated acids from storage containers to digestion containers. Faced with ever-increasing sample testing demands, laboratories often need to process dozens or even hundreds of samples. Manual acid addition is a highly repetitive, time-consuming, and labor-intensive process. From opening the container, aspirating, quantifying, transferring, adding, to closing, each sample requires individual handling, making the process cumbersome. In batch processing, this repetitive labor consumes a significant amount of valuable experimental time, significantly reducing testing efficiency. Operators must frequently open acid reagent storage containers, which can easily lead to burns or inhalation of toxic fumes. Furthermore, manual pipetting is affected by the stability of technique, visual errors, and accumulated fatigue, resulting in fluctuations in the added volume, impacting digestion efficiency, the recovery rate of target elements, and the accuracy and comparability of the final analytical results. Utility Model Content

[0004] The purpose of this invention is to provide a quantitative acid dosing instrument that can achieve quantitative acid dosing, effectively improve the accuracy and efficiency of acid dosing, reduce manpower consumption, and eliminate the need to frequently open the acid reagent storage container, thereby avoiding burns or inhalation of toxic gases when opening the acid reagent storage container and improving the safety of acid dosing.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a quantitative acid addition instrument, including a platform scale, an acid addition pump electrically connected to one side of the platform scale, a switch for controlling the opening and closing of the acid addition pump on the platform scale, the switch being configured to automatically shut off the acid addition pump when the weighing weight of the platform scale reaches a preset weight threshold, the inlet of the acid addition pump being connected to an acid storage bottle through an inlet pipe, an adjusting column on the platform scale, a support portion extending above the weighing surface of the platform scale on the adjusting column, a guide hole on the support portion, an addition pipe connected to the outlet of the acid addition pump, the addition pipe passing through the guide hole and its end suspended above the weighing surface.

[0006] A further improvement of this utility model is that an adjusting ring that can be adjusted and positioned along its height direction is sleeved on the adjusting column, and the supporting part is fixedly disposed on the adjusting ring.

[0007] A further improvement of this invention is that the adjusting ring and the adjusting column are positioned relative to each other through friction, so that the adjusting ring remains in a fixed position without external force and can be adjusted by manual force along the axial direction of the adjusting column.

[0008] A further improvement of this utility model is that the inlet pipe is connected to the acid storage bottle through a connector, and the connector is also connected to at least one storage bottle. The acid storage bottle and the storage bottle are both connected to the connector through connecting pipes, and each connecting pipe is equipped with an independent control valve.

[0009] A further improvement of this utility model is that the communicating vessel is a four-way connector, and the number of storage bottles is two.

[0010] A further improvement of this utility model is that the guide hole is set at an angle.

[0011] A further improvement of this utility model is that the inlet pipe, the filling pipe, and the connecting pipe are all made of soft pipe material resistant to corrosion by concentrated nitric acid and concentrated hydrochloric acid.

[0012] A further improvement of this invention is that the acid pump is a peristaltic pump resistant to corrosion from concentrated nitric acid and concentrated hydrochloric acid.

[0013] The beneficial effects of this utility model are as follows:

[0014] This invention, through the combination of an acid pump, a platform scale, and an adjusting column, enables precise acid addition, effectively improving the accuracy and efficiency of acid addition, reducing manpower consumption, and eliminating the need to frequently open the acid reagent storage container, thereby avoiding burns or inhalation of toxic gases when opening the acid reagent storage container and improving the safety of acid addition.

[0015] This invention achieves adjustable liquid filling height by incorporating an adjusting ring that can be adjusted and positioned along the height of the adjusting column. By controlling the raising and lowering of the support section, it can flexibly adapt to containers of different depths, solving the problem that fixed-height liquid filling pipes cannot handle diverse containers and improving the equipment's versatility.

[0016] The guide hole of this invention is angled, which applies lateral friction to the liquid dispensing tube passing through it, ensuring stable positioning of the end of the dispensing tube and preventing the end from shifting due to shaking during dripping. Simultaneously, the angled design allows the end of the dispensing tube to maintain a natural tilt angle, facilitating the guidance of acid to the inner wall of the container for wall-mounted dispensing during acid addition, effectively reducing the risk of splashing from direct liquid impact to the liquid surface or bottom of the container. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural schematic diagram of the present invention.

[0018] Figure 2 This is a top view of the structure of this utility model.

[0019] Figure 3 This is a side view of the structure of this utility model.

[0020] In the diagram, 1-platform scale, 2-acid pump, 3-inlet pipe, 4-acid storage bottle, 5-adjusting column, 6-support, 7-inlet pipe, 8-adjusting ring, 9-communicating device, 10-storage bottle, 11-control valve. Detailed Implementation

[0021] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments.

[0022] Example 1: Combination Figures 1-3 It is known that a quantitative acid addition instrument includes a platform scale 1, an acid addition pump 2 electrically connected to one side of the platform scale 1, a switch for controlling the opening and closing of the acid addition pump 2 on the platform scale 1, the switch being configured to automatically shut off the acid addition pump 2 when the weighing weight of the platform scale 1 reaches a preset weight threshold, the inlet of the acid addition pump 2 being connected to the acid storage bottle 4 through the inlet pipe 3, an adjustment column 5 being provided on the platform scale 1, a support part 6 extending above the weighing surface of the platform scale 1 on the adjustment column 5, a guide hole being provided on the support part 6, and an addition pipe 7 being connected to the outlet of the acid addition pump 2, the addition pipe 7 passing through the guide hole and its end being suspended above the weighing surface.

[0023] It should be understood that the electrical connection and logical relationship between the platform scale 1 and the acid pump 2, which is based on a preset weight threshold for opening and closing control, is a conventional technical means for the linkage control of electronic weighing equipment (such as electronic platform scales or balances with setpoint output function) and external actuators (such as pumps and valves) in the prior art. Those skilled in the art can implement this control function based on conventional knowledge, and this utility model does not involve any improvement to its program.

[0024] An adjusting ring 8 is fitted on the adjusting column 5, which can be adjusted and positioned along its height direction, and the support part 6 is fixedly mounted on the adjusting ring 8.

[0025] Optionally, the adjusting ring 8 and the adjusting column 5 are relatively positioned through frictional engagement, allowing the adjusting ring 8 to remain in a fixed position without external force and to be adjusted by manual force applied along the axial direction of the adjusting column 5. The relative positioning between the adjusting ring 8 and the adjusting column 5 is achieved through friction generated by an interference fit. Specifically, the adjusting ring 8 is made of elastic engineering plastic (such as polyoxymethylene POM), and its inner diameter is designed to be slightly smaller than the outer diameter of the adjusting column 5 (e.g., if the diameter of the adjusting column is 50 mm, then the inner diameter of the adjusting ring is 49.75 ± 0.05 mm). After assembly, the adjusting ring 8 undergoes elastic deformation, generating continuous positive pressure on the contact surface, thus forming sufficient static friction. This friction allows the adjusting ring 8 to reliably maintain a fixed position without external force, supporting the end of the liquid filling pipe 7. Simultaneously, this static friction can be overcome by manually applying an axial force, allowing the adjusting ring 8 to slide along the axial direction of the adjusting column 5 for height adjustment.

[0026] Optionally, the adjusting column 5 is provided with a positioning groove along its length, and the adjusting ring 8 is threaded with a locking bolt. The positioning of the adjusting ring 8 and the adjusting column 5 is achieved by one end of the locking bolt abutting against the positioning groove.

[0027] The inlet pipe 3 is connected to the acid storage bottle 4 via a connector 9. The connector 9 is also connected to at least one storage bottle 10. Both the acid storage bottle 4 and the storage bottle 10 are connected to the connector 9 via connecting pipes, each equipped with an independent control valve 11. When multiple storage bottles 10 are configured, the inlet of the acid pump 2 can be selectively connected to either the acid storage bottle 4 or any of the storage bottles 10. Different acid or reagent sources can be switched by operating the corresponding control valve 11. Preferably, the connector 9 is a four-way connector, and the number of storage bottles 10 is two.

[0028] Preferably, the storage bottle 10 can contain different strong acids (such as concentrated nitric acid or concentrated hydrochloric acid) or ordinary reagents (such as water or hydrogen peroxide). For samples that are difficult to digest (such as biological samples with high fat and protein content, or certain polymers), nitric acid alone may not be sufficient to completely destroy all organic matter or oxidize certain elements to the desired valence state. In this case, hydrogen peroxide can be selectively connected to the storage bottle 10 by operating the control valve 11. Adding hydrogen peroxide can significantly increase the oxidation potential of the system.

[0029] During use, different acids or reagents can be quickly selected by operating control valve 11, avoiding the need to change the acid storage bottle. When switching between different liquid sources (e.g., switching from hydrogen peroxide in storage bottle 10 to nitric acid in acid storage bottle 4), a waste liquid bottle needs to be placed on the platform scale 1, the control valve 11 corresponding to the target bottle (e.g., acid storage bottle 4) should be opened and other control valves 11 should be closed. The acid pump 2 should be started. After the acid pump 2 draws out a section of liquid (which is the residual liquid from the previous type in the pipeline, such as hydrogen peroxide), and the residual waste liquid from the previous type in the pipeline is completely drawn out (discharged into the waste liquid bottle), the next required liquid (nitric acid) can be drawn and used.

[0030] The guide hole is angled, preferably with an angle of 15°-45° between its axis and the vertical direction. The angled guide hole applies lateral constraint to the dispensing pipe 7, utilizing friction to ensure stable positioning of the end of the pipe 7 and prevent drip deviation. Furthermore, this angled arrangement allows the dispensing pipe 7 to extend at an angle, with its outlet tilted downwards towards the inner wall of the container, facilitating a slow, downward flow of acid along the container wall and effectively preventing splashing.

[0031] The inlet pipe 3, the filling pipe 7, and the connecting pipe are all made of flexible tubing resistant to strong acids (such as concentrated nitric acid and concentrated hydrochloric acid). Flexible tubing facilitates bending and accommodates length changes caused by the raising and lowering of the adjusting ring 8. Preferably, the flexible tubing is made of polytetrafluoroethylene (PTFE) or perfluoroether rubber.

[0032] The acid pump 2 is a peristaltic pump resistant to strong acids (such as concentrated nitric acid and concentrated hydrochloric acid). Peristaltic pumps offer advantages such as liquid contact only with the pump tubing, no seals, no valves, and ease of cleaning and flow path replacement, making them particularly suitable for conveying highly corrosive liquids. Preferably, the pump tubing of the peristaltic pump is made of one of the following materials: polytetrafluoroethylene, fluororubber, or perfluoroalkoxy resin, to ensure chemical stability under long-term contact with strong acids or strong oxidants. The pump head structure of the peristaltic pump (such as rollers, housing, etc.) should be compatible with and able to drive the aforementioned corrosion-resistant pump tubing.

[0033] When the peristaltic pump stops operating according to the target weight, the squeezing action exerted by its rollers on the pump tube creates an effective fluid isolation at the squeezing point, blocking the connection between the pipeline before the pump and the pipeline after the squeezing point (i.e., the liquid addition pipe 7). At this time, a certain amount of residual liquid still remains in the pipeline between the squeezing point and the outlet of the end of the liquid addition pipe 7. Under the action of gravity, the residual liquid tends to flow downwards. However, this tendency will cause a local negative pressure zone to form between the squeezing point and the nozzle. At the same time, the atmospheric pressure acting on the open port at the end of the liquid addition pipe 7 will act upwards on the liquid column. When the gravity of the liquid column, the negative pressure in the pipeline, and the atmospheric pressure reach equilibrium, the flow of residual liquid is effectively suppressed. Therefore, after the peristaltic pump stops, the residual liquid in the pipeline will not drip continuously, thus ensuring the accuracy of the acid addition action after the platform scale 1 reaches the preset weight threshold.

[0034] The working principle of Embodiment 1 of the quantitative acid addition instrument provided by the utility model is as follows:

[0035] In use, place the container to be added acid on the weighing surface of the platform scale 1. The adjusting column 5 drives the support part 6 to rise and fall through the adjusting ring 8, which can flexibly adjust the height of the end of the liquid addition tube 7 to adapt to different container depths. After setting the target weight threshold, the acid addition pump 2 is started, and the acid is pumped from the acid storage bottle 4 through the liquid inlet pipe 3, and then injected into the container through the liquid addition tube 7 suspended above the container. The platform scale 1 monitors the weight of the container in real time. When the weighing value reaches the preset threshold, the switch is automatically triggered to turn off the acid addition pump 2, so as to achieve precise quantitative acid addition.

[0036] In the description of this utility model, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Any equivalent structural or procedural transformations made using the content of this utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A dosing acid machine, characterized in that: The system includes a platform scale (1), an acid pump (2) electrically connected to one side of the platform scale (1), a switch for controlling the opening and closing of the acid pump (2) on the platform scale (1), the switch being configured to automatically shut off the acid pump (2) when the weighing weight of the platform scale (1) reaches a preset weight threshold, the inlet of the acid pump (2) being connected to an acid storage bottle (4) through an inlet pipe (3), an adjustment column (5) on the platform scale (1), a support part (6) extending above the weighing surface of the platform scale (1) on the adjustment column (5), a guide hole on the support part (6), and a liquid addition pipe (7) connected to the outlet of the acid pump (2), the liquid addition pipe (7) passing through the guide hole and its end suspended above the weighing surface.

2. The acid dosing instrument according to claim 1, characterized in that: An adjusting ring (8) that can be adjusted and positioned along its height direction is fitted on the adjusting column (5), and the supporting part (6) is fixedly mounted on the adjusting ring (8).

3. The acid dosing instrument according to claim 2, characterized in that: The adjusting ring (8) and the adjusting column (5) are positioned relative to each other through friction, so that the adjusting ring (8) remains in a fixed position without external force and can be adjusted by manually applying force along the axial direction of the adjusting column (5).

4. The acid dosing instrument of claim 1, wherein: The inlet pipe (3) is connected to the acid storage bottle (4) through the connector (9). The connector (9) is also connected to at least one storage bottle (10). The acid storage bottle (4) and the storage bottle (10) are both connected to the connector (9) through connecting pipes. Each connecting pipe is equipped with an independent control valve (11).

5. The acid dosing instrument according to claim 4, characterized in that: The communicating vessel (9) is a four-way connector, and the number of storage bottles (10) is two.

6. The acid dosing instrument of claim 1, wherein: The guide hole is angled.

7. The acid dosing instrument of claim 4, wherein: The inlet pipe (3), the filling pipe (7), and the connecting pipe are all soft pipes resistant to corrosion by concentrated nitric acid and concentrated hydrochloric acid.

8. The acid dosing instrument of claim 1, wherein: The acid pump (2) is a peristaltic pump resistant to corrosion from concentrated nitric acid and concentrated hydrochloric acid.

Images