High-precision rapid online analysis instrument for ammonia nitrogen water quality

Abstract

The utility model provides an ammonia nitrogen water quality high-precision rapid on-line analysis instrument, which comprises a sampling unit, a metering unit, a digestion and photoelectric colorimetric unit, a control unit and a man-machine interaction unit, the sampling unit comprises air, a sample, a reagent I, a reagent II, pure water, a standard solution I, a standard solution II, a standard solution III and a standard solution IV, the digestion and photoelectric colorimetric unit comprises a light source, a photoelectric detector and a reaction vessel, the light source and the photoelectric detector are arranged on the two sides of the reaction vessel respectively, the light source and the photoelectric detector are opposite in position, a heating wire is arranged on the outer side of the reaction vessel, and a temperature sensor is arranged in the reaction vessel; the sampling unit is connected with the input end of the metering unit through the multi-channel selector valve, and the output end of the metering unit is communicated with the reaction vessel. According to the utility model, a four-point calibration method is adopted, the detection accuracy can be improved, gradient dilution can be carried out, the detection range of a sample can be improved, in addition, the detection period can be shortened, the detection efficiency can be improved, and the structure is simple.

Description

Technical Field

[0001] The utility model relates to the technical field of water quality instrument analysis and detection, in particular to a high-precision rapid online analysis instrument for ammonia nitrogen water quality. Background Art

[0002] Water quality is of great significance in today's industrial water safety. Water quality monitoring can timely discover water quality problems and provide corresponding solutions for improving water quality so that water quality meets national standards. High-concentration ammonia nitrogen water mainly comes from the production processes of steel manufacturing, feed production, coal coking, chemical pharmaceuticals, oil refining and fertilizers and pesticides. These processes are very harmful to industrial water systems, so it is urgent to monitor the ammonia nitrogen content in industrial water.

[0003] At present, ammonia nitrogen detection includes Nessler reagent spectrophotometry, salicylic acid spectrophotometry, and ammonia sensitive electrode method. Among them, ammonia sensitive electrode has a short life and is easy to turn black during detection, which is not suitable for long-term online detection, analysis and control. Nessler reagent spectrophotometry requires toxic reagents, which pollutes the water quality to be tested and is not suitable for the technical requirements of green analysis required by the country. Salicylic acid spectrophotometry is now mostly used for ammonia nitrogen detection. Salicylic acid spectrophotometry has the following disadvantages: First, the two-point calibration method is generally used in market instruments, and the standard curve has distortion problems, resulting in low detection accuracy; second, the current detection range is generally small, generally 0-2mg / L, and it cannot detect ammonia nitrogen in industrial water with high concentrations of 0-100mg / L or above; third, the color development cycle is long. According to the national standard method, the color development time requires 60min, and the detection efficiency is low; fourth, the structure and process are complex, resulting in a long overall detection cycle. Utility Model Content

[0004] In order to solve the problems existing in the background technology, the utility model proposes a high-precision and rapid online analyzer for ammonia nitrogen water quality, comprising a sampling unit, a metering unit, a digestion and photoelectric colorimetric unit, a control unit and a human-computer interaction unit, wherein the sampling unit comprises air, a sample, a reagent one, a reagent two, pure water, a standard solution one, a standard solution two, a standard solution three and a standard solution four, the digestion and photoelectric colorimetric unit comprises a light source, a photoelectric detector and a reaction vessel, the light source and the photoelectric detector are respectively arranged at positions on both sides of the reaction vessel, and the light source and the photoelectric detector are positioned relative to each other, a heating wire is arranged on the outside of the reaction vessel, and a temperature sensor is arranged in the reaction vessel, the air, the sample, the reagent one, the reagent two, pure water, the standard solution one, the standard solution two, the standard solution three and the standard solution four are respectively connected to the input end of the metering unit through a multi-channel selection valve, the output end of the metering unit is connected to the reaction vessel, and the control unit is respectively connected to the multi-channel selection valve, the metering unit, the light source, the photoelectric detector, the heating wire, the temperature sensor and the human-computer interaction unit.

[0005] Preferably, the metering unit comprises a metering pump, an input end of the metering pump is connected to the multi-channel selection valve, and an output end of the metering pump is connected to the reaction vessel.

[0006] Preferably, the output end of the metering unit is also connected to a waste bucket.

[0007] Preferably, the metering unit is connected to the reaction vessel and the waste bucket respectively through a three-way valve, and the three-way valve is electrically connected to the control unit.

[0008] Preferably, a waste pump for pumping waste liquid is provided between the waste barrel and the three-way valve, and the waste pump is connected to the control unit.

[0009] Preferably, the sample, reagent 1, reagent 2, pure water, standard solution 1, standard solution 2, standard solution 3 and standard solution 4 are respectively placed in the sample tank, the first reagent tank, the second reagent tank, the pure water tank, the first standard solution tank, the second standard solution tank, the third standard solution tank and the fourth standard solution tank.

[0010] Preferably, the reaction vessel is fixed in a fixing frame, and the light source and the photodetector are fixed on the fixing frame.

[0011] The utility model has the following beneficial effects:

[0012] 1. The utility model adopts a four-point calibration method. By setting standard solution 1, standard solution 2, standard solution 3 and standard solution 4, the four standard solutions are sequentially aspirated during calibration to obtain the corresponding relationship between absorbance and concentration, and the K and B values ​​of the standard curve of the four-point calibration are saved, thereby improving the authenticity of the standard curve and the detection accuracy of the instrument, which can meet the user's demand for high-precision detection.

[0013] 2. The utility model can perform gradient dilution. By setting pure water and setting the range segment on the host computer, the sample and pure water are mixed in a gradient manner, thereby ensuring that the sample detection always meets the spectrophotometric principle, and ultimately improving the detection range of the sample, achieving a 1-20-fold dilution of the sample.

[0014] 3. The utility model adopts a heating wire for rapid heating, which can speed up the reaction time, shorten the detection cycle, and thus improve the detection efficiency.

[0015] 4. The utility model has a simple structure and no complicated process flow. The analysis and detection can be completed by using a metering pump, a multi-channel selection valve and a reaction dish. At the same time, air stirring is adopted, and no other external hardware devices need to be added, which can greatly save the instrument space. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0017] Numbers in the figure: 1. Sample; 2. Reagent 1; 3. Reagent 2; 4. Pure water; 5. Standard solution 1; 6. Standard solution 2; 7. Standard solution 3; 81. Standard solution 4; 51. Multi-channel selection valve; 61. Metering pump; 71. Reaction dish; 8. Heating wire; 9. Temperature sensor; 10. Light source; 11. Photoelectric detector; 12. Control unit; 13. Three-way valve; 14. Waste barrel; 15. Waste pump. DETAILED DESCRIPTION

[0018] In order to make the present invention clearer and more understandable, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the given embodiment is only one implementation method and does not represent all embodiments.

[0019] Combined with Figure 1 , a high-precision rapid online analyzer for ammonia nitrogen water quality, comprising a sampling unit, a metering unit, a digestion and photoelectric colorimetric unit, a control unit 12 and a human-computer interaction unit, wherein the sampling unit comprises air, a sample 1, a reagent 1 2, a reagent 2 3, pure water 4, a standard solution 1 5, a standard solution 2 6, a standard solution 3 7 and a standard solution 4 81, wherein the sample 1, the reagent 1 2, the reagent 2 3, the pure water 4, the standard solution 1 5, the standard solution 2 6, the standard solution 3 7 and the standard solution 4 81 are respectively placed in a sample tank 1, a first reagent tank, a second reagent tank, a pure water tank 4, a first standard solution tank, a second standard solution tank, a third standard solution tank and a fourth standard solution tank;

[0020] Specifically, the reagent one is sodium salicylate / sodium nitrosoferricyanide; the reagent two is sodium hydroxide / sodium dichloroisocyanurate; and the four standard solutions are: 0 mg / L, 0.5 mg / L, 1 mg / L, and 2 mg / L ammonia nitrogen standard solutions.

[0021] The digestion and photoelectric colorimetric unit comprises a light source 10 (697 nm), a photoelectric detector 11 and a reaction vessel 71. The light source 10 and the photoelectric detector 11 are respectively arranged at the positions on both sides of the reaction vessel 71, and the light source 10 and the photoelectric detector 11 are opposite to each other. A heating wire 8 is arranged on the outside of the reaction vessel 71, and a temperature sensor 9 is arranged inside the reaction vessel 71. The temperature sensor 9 detects the temperature inside the reaction vessel 71.

[0022] The air, sample 1, reagent 1 2, reagent 2 3, pure water 4, standard solution 1 5, standard solution 2 6, standard solution 3 7 and standard solution 4 81 are respectively connected to the input end of the metering unit through the multi-channel selection valve 51, that is, the multi-channel selection valve 51 includes nine input ports and one output port, and the air, sample 1, reagent 1 2, reagent 2 3, pure water 4, standard solution 1 5, standard solution 2 6, standard solution 3 7 and standard solution 4 81 are each connected to an input port of the multi-channel selection valve 51, and the input end of the metering unit is connected to the output port of the multi-channel selection valve 51. The metering unit is connected to the reaction vessel 71, and the output end of the metering unit is also connected to the waste bucket 14. Specifically, the metering unit includes a metering pump 61, the input end of the metering pump 61 is connected to the multi-channel selection valve 51, and the output end of the metering pump 61 is connected to the waste bucket 14 and the reaction vessel 71 respectively through the three-way valve 13; the metering pump 61 can accurately measure the sample 1 and the reagent, and the measurement accuracy is 0.02ml, and the multi-channel selection valve 51 can make the sample 1 and the reagent sequentially added to the reaction vessel 71;

[0023] The control unit 12 is respectively connected to the multi-channel selection valve 51, the metering unit, the light source 10, the photoelectric detector 11, the heating wire 8, the temperature sensor 9, the three-way valve 13 and the human-computer interaction unit. The control unit 12 controls the operation of each structure, presets the working procedure, thereby controlling the overall detection process, and transmits the detection signal to the human-computer interaction unit. The human-computer interaction unit is used to issue control instructions, display the reaction status, reaction progress and historical data, and the human-computer interaction unit can use a resistive touch screen.

[0024] Specifically, a waste pump 15 for pumping waste liquid is provided between the waste bucket 14 and the three-way valve 13, and the waste pump 15 is connected to the control unit 12. The waste bucket 14 is used to receive waste liquid discharged from the reaction vessel 71. After the sample 1 is tested, it is discharged from the reaction vessel 71 into the waste bucket 14. The waste pump 15 provides power for the transportation of the waste liquid.

[0025] Specifically, the reaction vessel 71 is fixed in a fixing frame, and the light source 10 and the photodetector 11 are fixed on the fixing frame.

[0026] Detection process: four standard solutions are sucked into the reaction dish 71 in turn, the corresponding relationship between absorbance and standard solution concentration is obtained through the light source 10 and the photoelectric detector 11, a four-point standard curve is obtained, and the K and B values ​​of the four-point calibrated standard curve are saved;

[0027] Pure water 4 enters the reaction dish 71 through the metering pump 61, and the light source 10 cooperates with the photoelectric detector 11 to detect the current light energy value, calculate the current absorbance of pure water 4, and then discharge the pure water 4 in the reaction dish 71 into the waste bucket 14; then the sample 1 is metered and passed into the reaction dish 71 for rinsing through the metering pump 61, and the rinsing is repeated for multiple times to avoid the pure water 4 remaining in the reaction dish 71, which affects the detection of the sample 1. The sample 1 is discharged into the waste bucket 14 after each rinsing; then the sample 1 in the sample tank is passed into the reaction dish 71 through the metering pump 61, and then the reaction dish 71 is fed to the sample 1 through the metering pump 61. Pure water 4 is added to dilute sample 1 to make sample 1 reach the required concentration gradient, and then reagent 1 and reagent 2 are added to the reaction dish 71 in sequence to pre-treat the diluted sample 1; air is then introduced into the reaction dish 71 through the metering pump 61, the sample 1 in the reaction dish 71 is stirred by air, and then the heating wire 8 is started to start heating; after the sample 1 is heated to 50 degrees and the color is developed for 90 seconds, the light energy value of the current sample 1 solution is detected, the absorbance of the current solution is calculated, and finally the current ammonia nitrogen concentration is calculated according to the four-point standard curve to realize the analysis and detection of ammonia nitrogen water quality.

[0028] The specific implementation methods of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the described implementation methods. For those skilled in the art, various changes, modifications, substitutions and variations of these implementation methods without departing from the principles and spirit of the present invention are still within the scope of protection of the present invention.

Claims

1. A high-precision rapid online analyzer for ammonia nitrogen water quality, characterized by: The invention comprises a sampling unit, a metering unit, a digestion and photoelectric colorimetry unit, a control unit (12) and a human-computer interaction unit. The sampling unit comprises air, a sample (1), a reagent 1 (2), a reagent 2 (3), pure water (4), a standard solution 1 (5), a standard solution 2 (6), a standard solution 3 (7) and a standard solution 4 (81). The digestion and photoelectric colorimetry unit comprises a light source (10), a photoelectric detector (11) and a reaction vessel (71). The light source (10) and the photoelectric detector (11) are respectively arranged at positions on both sides of the reaction vessel (71), and the positions of the light source (10) and the photoelectric detector (11) are opposite to each other. The reaction vessel (71) 1) A heating wire (8) is provided on the outside, a temperature sensor (9) is provided in the reaction vessel (71), the air, the sample (1), the reagent one (2), the reagent two (3), the pure water (4), the standard solution one (5), the standard solution two (6), the standard solution three (7) and the standard solution four (81) are respectively connected to the input end of the metering unit through a multi-channel selection valve (51), the output end of the metering unit is connected to the reaction vessel (71), and the control unit (12) is respectively connected to the multi-channel selection valve (51), the metering unit, the light source (10), the photoelectric detector (11), the heating wire (8), the temperature sensor (9) and the human-computer interaction unit.

2. According to claim 1, a high-precision rapid online analyzer for ammonia nitrogen water quality, characterized in that: The metering unit comprises a metering pump (61), wherein an input end of the metering pump (61) is connected to the multi-channel selection valve (51), and an output end of the metering pump (61) is connected to the reaction vessel (71).

3. A high-precision rapid online analyzer for ammonia nitrogen water quality according to claim 1 or 2, characterized in that: The output end of the metering unit is also connected to a waste bucket (14).

4. The high-precision rapid online analyzer for ammonia nitrogen water quality according to claim 3, characterized in that: The metering unit is respectively connected to the reaction vessel (71) and the waste bucket (14) via a three-way valve (13), and the three-way valve (13) is electrically connected to the control unit (12).

5. The high-precision rapid online analyzer for ammonia nitrogen water quality according to claim 4, characterized in that: A waste discharge pump (15) for pumping waste liquid is provided between the waste barrel (14) and the three-way valve (13), and the waste discharge pump (15) is connected to the control unit (12).

6. The high-precision rapid online analyzer for ammonia nitrogen water quality according to claim 1, characterized in that: The sample (1), reagent 1 (2), reagent 2 (3), pure water (4), standard solution 1 (5), standard solution 2 (6), standard solution 3 (7) and standard solution 4 (81) are respectively placed in the sample tank (1), the first reagent tank, the second reagent tank, the pure water tank (4), the first standard solution tank, the second standard solution tank, the third standard solution tank and the fourth standard solution tank.

7. The high-precision rapid online analyzer for ammonia nitrogen water quality according to claim 1, characterized in that: The reaction vessel (71) is fixed in a fixing frame, and the light source (10) and the photoelectric detector (11) are fixed on the fixing frame.

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