A rapid reaction cuvette for water quality free chlorine DPD detection

Abstract

The utility model discloses a kind of for water quality free chlorine DPD detection's fast reaction colorimetric dish, belong to water quality detection equipment technical field, including reagentless bottle, reagent bottle, connecting pipe and intercommunication control assembly, reagentless bottle adopts transparent material, reagent bottle is ultraviolet resistant material, connecting pipe two ends are respectively fixedly connected with left end cap and right end cap, left end cap and right end cap are respectively threadedly connected with reagentless bottle and reagent bottle, with square connecting hole in center, intercommunication control assembly is set in connecting pipe, to intercommunication or close reagentless bottle and reagent bottle. Through the reagent bottle set, the ultraviolet blocking rate of brown borosilicate glass used is more than 99%, effectively avoid free chlorine photolysis, detection result stability is improved by more than 15%, through the reagentless bottle set, the light scattering interference of high turbidity / chromaticity water sample is reduced using quartz material, absorbance detection precision is improved, 10mm / 50mm optical path is adapted, measurement range is 0.004-5mg / L, cover the detection demand of scene such as domestic drinking water, swimming pool water.

Description

Technical Field

[0001] This utility model relates to the field of water quality testing equipment technology, and more specifically, to a rapid reaction cuvette for detecting free chlorine (DPD) in water. Background Technology

[0002] In the detection of free chlorine in water, the DPD method is widely used due to its convenient operation and high sensitivity. Its core principle is to use the reaction of free chlorine with DPD reagent to generate a red compound, and then use a spectrophotometer to detect the absorbance at a wavelength of 515nm to calculate the free chlorine concentration.

[0003] Traditional cuvettes are mostly made of transparent glass, which cannot block ultraviolet light. Free chlorine (especially hypochlorous acid HClO) is prone to photolysis under ultraviolet light, leading to the loss of the target substance during the detection process and resulting in lower detection values. When detecting high-turbidity and high-color water samples, transparent cuvettes are easily affected by light scattering, which increases the error in absorbance detection. Furthermore, traditional detection requires manual addition of DPD reagent to the water sample on-site, and multiple steps of "sample addition-shaking-timing-detection" must be completed independently. The process is cumbersome, especially in outdoor emergency detection scenarios. Improper operation can easily affect accuracy. There are time differences in the reagent dissolution and mixing process, and free chlorine in the water sample decays easily over time (the decay rate can reach 15% within 30 minutes), further amplifying the detection error.

[0004] In view of this, the present invention is proposed to solve the above-mentioned technical problems. Utility Model Content

[0005] The purpose of this invention is to provide a rapid reaction cuvette for detecting free chlorine (DPD) in water, so as to solve the technical problems of existing cuvettes not being able to block ultraviolet light and the complicated operation of adding DPD reagent.

[0006] To achieve the above objectives, this utility model provides the following technical solution: A rapid reaction cuvette for detecting free chlorine (DPD) in water quality, comprising: No reagent bottle; the reagent bottle is made of transparent material. The reagent bottle is made of UV-resistant material. The connecting tube has a left end cap and a right end cap fixedly connected to both ends of the connecting tube. The left end cap and the right end cap are threaded to the reagent bottle and the reagent bottle, respectively. The tube has a square connection hole in the center. A connection control component is disposed within the connecting tube to connect or close the reagent bottle and the reagent bottle.

[0007] Furthermore, the connection control component includes a vertically arranged elastic pressing structure, the upper end of which extends through the outside of the connecting tube, and a pressing part is fitted onto the elastic pressing structure inside the square connecting hole; The square connecting hole has grooves on both the front and rear sides along its length, and a sliding movable part is installed in the groove. The pressing part abuts against the movable part.

[0008] Furthermore, the movable part includes a sealing block that mates with the square connecting hole. The sealing block is detachably connected to the square connecting hole. A central rod is vertically arranged on one end of the sealing block near the right end cover. Limit rods are provided on both sides of the middle of the central rod. A slide rod is provided along the length of the slide groove. The end of the limiting rod away from the center rod is fitted onto the slide rod. A first spring is provided between the side of the limiting rod away from the sealing block and the inner wall of the slide groove.

[0009] Furthermore, a sealing ring is provided on the sealing block along its circumference, and the sealing ring is in frictional connection with the inner wall of the square connecting hole.

[0010] Furthermore, the end of the center rod away from the sealing block has a first inclined surface that slopes downwards, and the pressing part has a second inclined surface that slopes downwards on the side near the center rod, with the second inclined surface fitting against the first inclined surface.

[0011] Furthermore, multiple flow-dispersing ribs are evenly distributed along the height direction at the bottom of the reagent bottle.

[0012] Furthermore, the elastic pressing structure includes a pressing rod, the upper end of which extends through the outside of the connecting tube, and a vertical hole at the bottom of the pressing rod. A sliding bottom rod is installed inside the vertical hole, and a second spring is directly installed between the bottom of the pressing rod and the bottom of the square connecting hole.

[0013] Furthermore, the reagent bottles are fitted with insulating sleeves.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. The reagent bottles are made of brown borosilicate glass with an ultraviolet blocking rate of >99%, which effectively avoids the photolysis of free chlorine and improves the stability of the test results by more than 15%.

[0015] 2. By using a reagent-free bottle and quartz material, the light scattering interference of high turbidity / color water samples is reduced, improving the absorbance detection accuracy. It is compatible with 10mm / 50mm optical path and has a measurement range of 0.004-5mg / L, covering the detection needs of drinking water, swimming pool water and other scenarios. It is compatible with QYJ-Ⅱ portable colorimeter and various spectrophotometers.

[0016] 3. Furthermore, through the established connectivity control components, there is no need for separate reagent addition and timing. In outdoor emergency scenarios, a single person can operate the system, reducing the time consumption by more than 60%. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but do not constitute an undue limitation of the present invention. Obviously, the drawings described below are merely some embodiments; those skilled in the art can obtain other drawings based on these drawings without creative effort. In the drawings: Figure 1 This is a schematic diagram of the structure of the rapid reaction cuvette for detecting free chlorine (DPD) in water provided in this embodiment of the application; Figure 2 for Figure 1 A schematic diagram of the structure after removing the insulation jacket; Figure 3 for Figure 2 A schematic diagram of the structure after removing the reagent bottle and the reagent bottle; Figure 4 for Figure 3 A sectional view; Figure 5 A schematic diagram of the moving parts of a rapid reaction cuvette for detecting free chlorine (DPD) in water provided in an embodiment of this application; Figure 6 This is a schematic diagram of the elastic pressing structure of a rapid reaction cuvette for detecting free chlorine (DPD) in water, provided in an embodiment of this application.

[0018] Reference numerals: 1. No reagent bottle; 2. Reagent bottle; 3. Connecting tube; 4. Insulation sleeve; 5. Baffle rib; 6. Left end cap; 7. Right end cap; 8. Sealing block; 9. Center rod; 10. Limiting rod; 11. Pressing rod; 12. Pressing part; 13. Bottom rod; 14. Second spring; 15. Slide rod; 16. First spring; 17. Sealing ring. Detailed Implementation

[0019] The technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments.

[0020] See Figures 1 to 6 As shown, a rapid reaction cuvette for detecting free chlorine (DPD) in water includes: a reagent-free bottle 1, a reagent bottle 2, a connecting tube 3, and a communication control component. The reagent-free bottle 1 is made of transparent material, and the reagent bottle 2 is made of UV-resistant material. The connecting tube 3 is fixedly connected to a left end cap 6 and a right end cap 7 at both ends, respectively. The left end cap 6 and the right end cap 7 are threadedly connected to the reagent-free bottle 1 and the reagent bottle 2, respectively, to facilitate the disassembly and assembly of the reagent-free bottle 1 and the reagent bottle 2. The connecting tube 3 has a square connection hole in the center, and the communication control component is set inside the connecting tube 3 to connect or close the reagent-free bottle 1 and the reagent bottle 2.

[0021] It should be noted that reagent bottle 1 is made of high-transmittance UV-grade quartz glass (transmittance range 190-2500nm), used for absorbance detection at 515nm wavelength by spectrophotometer, avoiding UV absorption interference. Optical path: 10mm or 50mm, adaptable to different detection limit requirements of HJ586-2010 standard. As the absorbance detection area, the quartz material avoids UV absorption interference, ensuring stable transmission of light signal at 515nm wavelength, with a volume of 10-15mL. Reagent bottle 2 is made of dark brown borosilicate glass (UV blocking rate >99%@200-400nm), pre-filled with DPD lyophilized reagent (powder or tablet). The brown glass blocks UV light, preventing free chlorine from photodegrading before reaction, with a capacity of 10mL standard water sample volume.

[0022] In the above solution, the reagent bottle 2, made of brown borosilicate glass with an ultraviolet blocking rate of >99%, effectively avoids photolysis of free chlorine, improving the stability of the detection results by more than 15%. The reagent-free bottle 1, made of quartz material, reduces light scattering interference from high turbidity / color water samples, improving absorbance detection accuracy. It is compatible with 10mm / 50mm optical path lengths and has a measurement range of 0.004-5mg / L, covering the detection needs of drinking water, swimming pool water, and other scenarios. It is compatible with the QYJ-Ⅱ portable colorimeter and various spectrophotometers. Through the set connection control components, there is no need for independent reagent addition and timing. In outdoor emergency scenarios, it can be operated by a single person, reducing the time by more than 60%.

[0023] See some possible implementations. Figure 3 and Figure 4 As shown, the communication control component includes a vertically arranged elastic pressing structure. The upper end of the elastic pressing structure extends through the outside of the connecting pipe 3. A pressing part 12 is fitted on the elastic pressing structure inside the square connecting hole. Sliding grooves are provided on both the front and rear sides of the square connecting hole along its length. Sliding movable parts are provided in the sliding grooves, and the pressing part 12 abuts against the movable parts.

[0024] In the above scheme, by pressing the elastic pressing structure and the pressing part 12, the elastic pressing structure moves down, causing the movable part to extend out of the square connecting hole along the slide groove, thereby connecting the reagent bottle 1 and the reagent bottle 2. After the connection, the test water sample pre-filled in the reagent bottle 1 is mixed with the DPD lyophilized reagent in the reagent bottle 2, and the mixture is achieved by shaking.

[0025] See some possible implementations. Figures 3 to 6As shown, the movable part includes a sealing block 8 that mates with a square connecting hole. The sealing block 8 is detachably connected to the square connecting hole. A central rod 9 is vertically arranged at one end of the sealing block 8 near the right end cover 7. Limiting rods 10 are arranged on both sides of the middle of the central rod 9. A sliding rod 15 is arranged in the sliding groove along its length. The end of the limiting rod 10 away from the central rod 9 is fitted onto the sliding rod 15. A first spring 16 is arranged between the side of the limiting rod 10 away from the sealing block 8 and the inner wall of the sliding groove.

[0026] In the above scheme, when the center rod 9 is pushed to make the sealing block 8 extend out of the square connection hole, the limiting rod 10 slides along the length direction of the slide rod 15 at the same time, which will stretch the first spring 16. When the center rod 9 is stopped, the first spring 16 resets and drives the sealing block 8 to move into the square connection hole through the limiting rod 10, thereby sealing the square connection hole through the sealing block 8.

[0027] See some possible implementations. Figure 6 As shown, a sealing ring 17 is provided on the sealing block 8 along its circumference. The sealing ring 17 is in frictional connection with the inner wall of the square connecting hole. The sealing ring 17 is used to improve the sealing performance between the sealing block 8 and the square connecting hole.

[0028] See some possible implementations. Figures 4 to 6 As shown, the center rod 9 has a first inclined surface that slopes downwards at the end away from the sealing block 8, and the pressing part 12 has a second inclined surface that slopes downwards on the side near the center rod 9. The second inclined surface is in contact with the first inclined surface.

[0029] See some possible implementations. Figure 1 and Figure 2 As shown, multiple baffles 5 are evenly arranged along the height direction at the bottom of reagent bottle 2. The cross-section of the baffles 5 is triangular, avoiding the light transmission window to ensure that the light path is not obstructed and does not affect light transmission.

[0030] See some possible implementations. Figures 4 to 6 As shown, the elastic pressing structure includes a pressing rod 11, the upper end of which extends through the outside of the connecting tube 3. A vertical hole is provided at the bottom of the pressing rod 11, and a sliding bottom rod 13 is provided inside the vertical hole. A second spring 14 is directly provided between the bottom of the pressing rod 11 and the bottom of the square connecting hole.

[0031] In the above scheme, when the water sample to be tested is mixed with the DPD lyophilized reagent, the pressing rod 11 is pressed down. The pressing rod 11 moves down, and the bottom rod 13 extends into the vertical hole at the bottom of the pressing rod 11. At the same time, the second spring 14 is compressed. The pressing rod 11 moves down, driving the pressing part 12 to move down synchronously. The pressing part 12 moves down and squeezes the first inclined surface of the center rod 9 through the second inclined surface, so that the center rod 9 drives the sealing block 8 to extend out of the square connection hole. When the pressing rod 11 is released, the pressing rod 11 moves up due to the elastic force of the second spring 14. At the same time, the limiting rod 10 is pulled by the first spring 16, driving the sealing block 8 to re-enter the square connection hole to seal the square connection hole. When the pressing rod 11 is stationary, the sealing block 8 is aligned with the left end of the square connection hole.

[0032] See some possible implementations. Figure 1 and Figure 2 As shown, reagent bottle 2 is fitted with an insulating sleeve 4.

[0033] Working principle Preparation phase: Before leaving the factory, rotate reagent bottle 2 to remove reagent bottle 2, pre-fill reagent bottle 2 with a quantitative amount of DPD lyophilized reagent (such as 1 Lovibond DPD tablet or the corresponding dose of 530100 powder), and then tighten reagent bottle 2 back onto the right end cap 7. Before testing, rotate the reagent-free bottle 1 to remove it, pour the water sample to be tested into the reagent-free bottle 1 up to the graduation line (10mL), and then tighten the reagent-free bottle 1 onto the left end cap 6.

[0034] Reaction phase: Press down on the pressing rod 11, and the pressing rod 11 moves down. The bottom rod 13 extends into the vertical hole at the bottom of the pressing rod 11, while compressing the second spring 14. The pressing rod 11 moves down, causing the pressing part 12 to move down synchronously. The pressing part 12 moves down and squeezes the first inclined surface of the center rod 9 through the second inclined surface, so that the center rod 9 drives the sealing block 8 to extend out of the square connection hole. At this time, the water sample to be tested is mixed with the DPD freeze-dried reagent. Then, when the pressing rod 11 is released, the pressing rod 11 moves up due to the elastic force of the second spring 14. At the same time, the limiting rod 10 is pulled by the first spring 16, which drives the sealing block 8 to re-enter the square connection hole and seal the square connection hole. Shake the cuvette up and down for 3-5 seconds to allow liquid convection to fully mix the water sample in reagent bottle 1 with the DPD reagent in reagent bottle 2. Let the cuvette stand for 30 seconds (in a dark environment, protected by the brown glass in the reagent area) to complete the colorimetric reaction (free chlorine reacts with DPD to form a stable red compound).

[0035] Testing phase: Place the cuvette into the cuvette cell of the spectrophotometer, aligning the light-transmitting side of the reagent-free bottle 1 with the light path (quartz material ensures that 515nm wavelength light passes through without interference). The spectrophotometer reads the absorbance value at a wavelength of 515 nm, and automatically converts it into the concentration of free chlorine in the water sample (mg / L) using a standard curve, thus completing the detection.

[0036] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A rapid reaction cuvette for detecting free chlorine (DPD) in water, characterized in that, include: A reagent-free bottle (1) is made of transparent material; Reagent bottle (2), wherein the reagent bottle (2) is made of UV-resistant material; Connecting tube (3), with a left end cap (6) and a right end cap (7) fixedly connected to both ends of the connecting tube (3), the left end cap (6) and the right end cap (7) being threadedly connected to the reagent bottle (1) and the reagent bottle (2) respectively, and having a square connecting hole in the center; A connection control component is disposed within the connecting tube (3) to connect or close the reagent-free bottle (1) and the reagent bottle (2).

2. The rapid reaction cuvette for detecting free chlorine (DPD) in water quality according to claim 1, characterized in that, The communication control component includes a vertically arranged elastic pressing structure, the upper end of which extends through the outside of the connecting pipe (3), and a pressing part (12) is fitted on the elastic pressing structure inside the square connecting hole. The square connecting hole has grooves on both sides along its length, and a sliding movable part is provided in the groove. The pressing part (12) abuts against the movable part.

3. The rapid reaction cuvette for detecting free chlorine (DPD) in water quality according to claim 2, characterized in that, The movable part includes a sealing block (8) that mates with a square connecting hole. The sealing block (8) is detachably connected to the square connecting hole. A central rod (9) is vertically arranged on one end of the sealing block (8) near the right end cap (7). Limiting rods (10) are provided on both sides of the middle part of the central rod (9). A slide rod (15) is provided in the groove along its length. The end of the limiting rod (10) away from the center rod (9) is fitted onto the slide rod (15). A first spring (16) is provided between the side of the limiting rod (10) away from the sealing block (8) and the inner wall of the groove.

4. The rapid reaction cuvette for detecting free chlorine (DPD) in water quality according to claim 3, characterized in that, The sealing block (8) is provided with a sealing ring (17) along its circumference, and the sealing ring (17) is frictionally connected to the inner wall of the square connecting hole.

5. The rapid reaction cuvette for detecting free chlorine (DPD) in water quality according to claim 3, characterized in that, The center rod (9) has a first inclined surface that slopes downward at the end away from the sealing block (8), and the pressing part (12) has a second inclined surface that slopes downward at the side near the center rod (9), with the second inclined surface fitting against the first inclined surface.

6. The rapid reaction cuvette for detecting free chlorine (DPD) in water quality according to claim 5, characterized in that, The reagent bottle (2) has multiple turbulence ribs (5) evenly arranged along its height direction at the bottom.

7. The rapid reaction cuvette for detecting free chlorine (DPD) in water quality according to claim 2, characterized in that, The elastic pressing structure includes a pressing rod (11), the upper end of which extends through the outside of the connecting tube (3), a vertical hole is provided at the bottom of the pressing rod (11), a sliding bottom rod (13) is provided in the vertical hole, and a second spring (14) is directly provided at the bottom of the pressing rod (11) and the bottom of the square connecting hole.

8. The rapid reaction cuvette for detecting free chlorine (DPD) in water quality according to claim 6, characterized in that, The reagent bottle (2) is fitted with an insulating sleeve (4).

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