A fully automatic rapid silicate detector and a detection method

Abstract

This invention relates to a fully automated rapid silicate concentration detection method, comprising: S1, establishing a standard curve based on a silicate standard solution; S2, performing fully automated rapid silicate concentration detection based on the standard curve; S1 includes: S11, preparing the standard solution; S12, performing automatic sample injection and detection; S13, signal acquisition and processing; S14, fitting the standard curve; S15, verifying and storing the standard curve; S16, performing anti-interference verification, including: adding interfering substances to the standard solution to verify the reliability of the curve; S2 includes: S21, performing range calibration using the standard solution before sample measurement, setting the photomultiplier tube's high voltage value to V1 to achieve the standard measurement range; S22, preparing reagent A (2% ammonium molybdate), reagent B (4% dilute sulfuric acid), and reagent C (basic luminescent agent) required for fully automated rapid silicate concentration detection; S23, performing fully automated rapid silicate concentration detection based on the standard curve. A corresponding fully automated rapid silicate detector is also disclosed.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of calibration technology of analytical instruments, and in particular to a full-automatic rapid silicate detector and a detection method. BACKGROUND

[0002] The treatment and monitoring of boiler water in thermal power plants is a crucial link, which is directly related to the safe operation of the boiler, energy efficiency and overall economic benefit of the power plant. The silicate content in the boiler water is one of the important indicators for measuring the quality of the boiler water. At present, most thermal power plants and semiconductor industries use silicate analyzers based on the silicon molybdenum blue colorimetric principle as the main detection means when detecting the concentration of silicate ions. During the detection process, a certain amount of reagent needs to be manually added, and after the chemical color reaction occurs, the silicate analyzer is used for measurement. This process has low automation degree, long detection time and large human influence factors. The chemiluminescence method (silicon molybdenum heteropoly acid photometric method) is an effective method for rapid measurement of trace silicate. The silicate reacts with molybdate under certain conditions to form silicon molybdenum heteropoly acid, which can produce strong chemical luminescence when reacting with luminol. The concentration of the reactant can be directly measured by detecting the chemical luminescence intensity. The luminescence reaction is completed within tens of seconds. The chemiluminescence method has the advantages of high sensitivity, no need for external excitation light source, avoidance of background light and stray light interference, and reduction of noise.

[0003] The domestic silicate detection method based on chemiluminescence was first proposed by Chen Yixin et al. in 1997. In 2000, Zhang Wenzhao developed a silicate monitor based on the chemiluminescence principle, with a response time of 2.5 min, a detection range of 0-50 ug / L (0-200 ug / L), and an accuracy of ±2 ug / L (2%). In 2003, Li Changyou of Dalian University of Technology developed an intelligent online silicate concentration detector based on the chemiluminescence method, with a detection range of 0-200 ug / L and an error of ≤2%. However, it has not been put into practical use and productization, and the experimental data support is not available, so the performance indicators cannot be verified. In 2014, Sun Weizhi of Dalian University of Technology designed an intelligent chemical analyzer for detecting silicate ion concentration based on the luminol chemiluminescence principle. The software design, circuit design and structure design were completed. However, due to the problem of chemical formula, the experimental conditions are not available.

[0004] In summary, the existing technology has the technical defects of slow chemical reaction rate and poor consistency due to the addition method of the luminescence dish, great influence of high pressure fluctuation on signal acquisition, no elimination means, no consideration of temperature influence, and too much or too little addition of chemical formula and reagent, resulting in poor measurement repeatability, low measurement precision and high detection limit. SUMMARY

[0005] The application aims to provide a full-automatic rapid silicate detector and a detection method, and the application provides a full-automatic rapid silicate detection method with good repeatability and high measurement accuracy based on the chemical luminescence principle, and realizes productization, effectively solves the problems of poor measurement repeatability, low measurement accuracy and high detection limit in the traditional technology, and the performance indicators of the method can reach: measurement repeatability < 1%, measurement accuracy ± 0.75 ug / L, and detection limit 0.1 ug / L.

[0006] From the research and development process of the silicate detector based on the chemical luminescence method, it can be seen that poor measurement repeatability and low measurement accuracy are important factors affecting the development of the chemical luminescence method in silicate detection. According to the chemical luminescence principle, the chemical luminescence intensity depends on the rate of chemical reaction, the rate of generation of excited state products and the luminescence efficiency of excited state substances. For the fixed chemical reaction of silicomolybdate oxidizing luminol, the rate of generation of excited state products and the luminescence efficiency of excited state substances are constant values, so reducing the factors affecting the rate of chemical reaction can effectively improve the detection accuracy of silicate.

[0007] The first aspect of the application is to provide a full-automatic rapid silicate detection method, comprising:

[0008] S1, establishing a standard curve based on a silicate standard solution;

[0009] S2, performing full-automatic rapid silicate concentration detection based on the standard curve;

[0010] The S1 comprises:

[0011] S11, preparing a standard solution;

[0012] S12, performing automatic sampling and detection;

[0013] S13, signal acquisition and processing;

[0014] S14, fitting a standard curve;

[0015] S15, verifying and storing the standard curve;

[0016] S16, performing anti-interference verification, comprising: adding an interference substance to the standard solution to verify the reliability of the curve;

[0017] The S2 comprises:

[0018] S21, performing range calibration using a standard solution before sample measurement, and setting the high voltage value of the photomultiplier tube (19) to V1 to achieve the standard measurement range;

[0019] S22, preparing reagent A, reagent B and reagent C required for the full-automatic rapid silicate concentration detection;

[0020] S23, automatically detecting the concentration of silicate based on the standard curve.

[0021] Preferably, the S11 comprises:

[0022] (1) preparing a stock solution, wherein the stock solution comprises silicate standard substance and ultrapure water;

[0023] (2) diluting the concentration gradient based on a dilution algorithm, wherein the concentration gradient is: 0.0, 0.5, 1.0, 5.0, 10.0, 20.0, 50.0, 100.0 μg / L; the dilution algorithm is shown in formula (1):

[0024]

[0025] wherein, V add represents the volume of added stock solution, in μL; V cell represents the volume of the luminescence dish, C target is the target concentration after dilution; C stock represents the concentration before dilution.

[0026] Preferably, the S12 comprises:

[0027] (1) setting instrument parameters, the instrument parameters include color temperature, ammonium molybdate addition amount, reaction time, dilute sulfuric acid addition amount, basic luminescent agent addition amount and detection wavelength; wherein the set value of the color temperature is 25.0±0.1℃, which is used for the constant temperature device (2) to control the reaction temperature; the set value of the ammonium molybdate addition amount is 1.00±0.01 mL, which is used for the first metering pipe (11) to control; the set value of the reaction time is 120±1 s, which is used for controlling the complete generation of silicon molybdate yellow; the dilute sulfuric acid addition amount is 0.50±0.01 mL, which is used for the second metering pipe (13) to control, eliminating the interference of PO4 3- ; the set value of the basic luminescent agent addition amount is 0.50±0.01 mL, which is used for the third metering pipe (15) to control the reduction of silicon molybdate blue; the set value of the detection wavelength is 810±2 nm, which is used for the photomultiplier tube (19) to be in the best response interval;

[0028] (2) performing automatic timing control.

[0029] Preferably, the S13 comprises:

[0030] (1) photoelectric signal conversion, wherein the output current of the photomultiplier tube (19) is shown in formula (2):

[0031] I out = I dark + K·e -εcd (2);

[0032] wherein ε represents the molar absorption coefficient of silicon molybdenum blue; c represents the concentration of silicate, in mol / L; d represents the optical path; K represents the optical gain factor; I dark represents the dark field signal;

[0033] (2) Calculate the absorbance, as shown in formula (3):

[0034]

[0035] wherein I blank represents the ultrapure water blank signal, I sample represents the sample signal.

[0036] Preferably, the S14 comprises:

[0037] (1) Based on the least square method regression preliminary fitting standard curve, as shown in formula (4):

[0038] A=a·c+b (4);

[0039] wherein a is the slope, indicating the sensitivity, the theoretical value is ≥0.035 Abs / (μg / L); b is the intercept, indicating the blank value, and the requirement is |b|≤0.005 Abs;

[0040] (2) Based on the index to verify the fitting quality of the preliminary fitting standard curve and determine the fitting quality as the standard curve, wherein the index includes verifying the correlation coefficient r≥0.9995 based on the Pearson test method, verifying the residual standard deviation Sres≤0.002 Abs based on calculating the deviation of each point, and verifying the slope RSD≤1.0% based on repeating the curve establishment for 3 times.

[0041] Preferably, the S15 comprises:

[0042] (1) Based on the standard addition recovery experiment to verify the accuracy;

[0043] (2) Store and call the curve, including:

[0044] Store data through the circuit board (18) and embed the automatic failure mechanism to calibrate the prompt, wherein the automatic failure mechanism includes forced recalibration when the first calibration is more than 30 days, and alarm prompt when the blank value drifts >±0.003 Abs.

[0045] Preferably, the S22 comprises:

[0046] Prepare the reagent A, wherein the reagent A is 2% ammonium molybdate, including: use a 1000 mL volumetric flask, inject 800 mL of silicon-free water, add 20 g of analytical pure ammonium molybdate, fully dissolve, and then add water to constant volume to 1000 mL;

[0047] Prepare reagent B, wherein reagent B is 4% dilute sulfuric acid, by: using a 1000mL volumetric flask, first pour in 800mL of silica-free water, then add 27mL of analytical grade concentrated sulfuric acid, and add water to make up to 1000mL.

[0048] Prepare reagent C, wherein reagent C is an alkaline luminescent agent, comprising: first pouring 800 mL of silica-free water into a graduated polyethylene reagent bottle, then adding 40 g of analytical grade NaOH granules and 0.2 g of luminescent agent, dissolving them completely, and then adding water to 1000 mL.

[0049] Preferably, S23 includes:

[0050] (1) Take 80-100 mL of sample water and put it into the sample cup (1). The sample water flows into the luminescent dish (17) through the constant temperature device (2).

[0051] (2) Quantitative dosing of water samples based on a centrally diffused dosing method; including:

[0052] A. After filling the luminescent dish (17) with sample water, drain it through the overflow pipe (21). At the same time, the drain pump (23) starts running. After a few seconds, the sample water in the luminescent dish (17) is drained. At this time, the drain pump (23) stops working.

[0053] B. Excess sample water continues to enter the luminescent dish (17) and overflows. After no more water sample flows out of the overflow tube (21), the volume of sample water in the luminescent dish (17) is about 18 mL.

[0054] C. Open the main three-way valve (22) and the drain pump (23) to remove the excess sample water from the luminescent dish (17) and measure the sample water volume to approximately 15 mL;

[0055] (3) Add reagent A and reagent B sequentially to a fixed amount of sample water; including:

[0056] A. Open the suction pump (3), the second three-way valve (6) and the third three-way valve (7) to draw the reagent A into the first metering tube (11). When the first liquid level sensor (12) measures the liquid level signal, close the suction pump (3), the second three-way valve (6) and the third three-way valve (7), and open the blowing pump (4), the first three-way valve (5) and the fourth three-way valve (8) to blow a quantitative amount of reagent A (0.5 mL to 1 mL) into the luminescent dish (17).

[0057] B. After reagent A is added, close the air pump (4), the first three-way valve (5) and the fourth three-way valve (8); wait 1 second, open the suction pump (3), the second three-way valve (6) and the third three-way valve (7) to draw reagent B into the second metering tube (13). When the second liquid level sensor (14) measures the liquid level signal, close the suction pump (3), the second three-way valve (6) and the third three-way valve (7), open the air pump (4), the third three-way valve (6) and the fifth three-way valve (9) to blow 0.5 mL to 1 mL of quantitative reagent B into the luminescent dish (17);

[0058] (4) Preparations before the chemical reaction, lasting 30-60 seconds; including:

[0059] A. After reagent B is added, continue to blow air for a few seconds. The bubbles enter the luminescent dish (17) to stir the liquid. The air is discharged from the exhaust pipe (20). Then close the air pump (4), the third three-way valve (6) and the fifth three-way valve (9).

[0060] B. Wait for the chemical reaction to proceed for several tens of seconds. During the waiting period, the circuit board (18) continuously reads the high voltage value V2 of the photomultiplier tube (19) at certain time intervals to determine whether |V2-V1|≤3V.

[0061] If |V2-V1|≤3V, then proceed directly to the fully automated rapid silicate concentration detection step based on reagent C and the standard curve.

[0062] If |V2-V1|>3V, then high voltage feedback self-adjustment is performed until |V2-V1|≤3V, and the high voltage feedback self-adjustment is completed within a few seconds;

[0063] C. After the high-pressure feedback self-adjustment is completed, open the suction pump (3), the first three-way valve (5), and the second three-way valve (6);

[0064] (5) Fully automated rapid silicate concentration detection based on reagent C and the aforementioned standard curve; including:

[0065] A. Draw the drug C into the third metering tube (15). When the third liquid level sensor (16) measures the liquid level signal, close the suction pump (3), the first three-way valve (5) and the second three-way valve (6), and open the blowing pump (4), the third three-way valve (7) and the sixth three-way valve (10). Spray 1 mL to 3 mL of the quantitative drug C into the light-emitting dish (17) in a center emission manner.

[0066] B. In the luminescent dish (17), the reagent C reacts chemically with the mixed liquid to generate radiant light, which is received by the photomultiplier tube (19) and transmitted to the circuit board (18). The silicate concentration value in the sample water is obtained according to the standard curve.

[0067] A second aspect of the present invention is to provide a fully automated rapid silicate detector for implementing the method of the first aspect, comprising:

[0068] Sample inlet cup (1), constant temperature device (2), suction pump (3), blowing pump (4), first three-way valve (5), second three-way valve (6), third three-way valve (7), fourth three-way valve (8), fifth three-way valve (9), sixth three-way valve (10), first metering tube (11), first liquid level sensor (12), second metering tube (13), second liquid level sensor (14), third metering tube (15), third liquid level sensor (16), light-emitting dish (17), circuit board (18), photomultiplier tube (19), exhaust pipe (20), overflow pipe (21), main three-way valve (22), and drain pump (23); wherein:

[0069] (i) The injection cup (1) and the constant temperature device (2) constitute the injection system. The injection cup (1) is used as the inlet of the original water sample, with a capacity of 5-50 mL, and is resistant to acid and alkali corrosion. It is connected to the constant temperature device (2) through a silicone tube. The constant temperature device (2) is used to implement constant temperature control at 25±0.1℃, thereby eliminating the influence of temperature on the colorimetric reaction.

[0070] (ii) The suction pump (3) and the blowing pump (4) constitute a fluid drive system. The suction pump (3) is used to generate negative pressure to extract the sample and is connected to the first three-way valve (5) to control the direction of sample injection. The blowing pump (4) is used to generate positive pressure to drive the reagent mixing and is connected to the second three-way valve (6), the third three-way valve (7) and the fourth three-way valve (8) respectively to drive different reagents.

[0071] (III) The first three-way valve (5), the second three-way valve (6), the third three-way valve (7), the fourth three-way valve (8), the fifth three-way valve (9), the sixth three-way valve (10), and the main three-way valve (22) constitute a three-way valve array, serving as the core flow control component, wherein:

[0072] The first three-way valve (5) controls the sample flow and is used to switch the sample injection and / or cleaning path. The first three-way valve (5) is connected to the suction pump (3) and the first metering tube (11), the second metering tube (13) and the third metering tube (15) respectively.

[0073] The second three-way valve (6) uses ammonium molybdate reagent as the control object and is used to accurately add reagent A. The second three-way valve (6) is connected to the air pump (4) and the first metering tube (11) respectively.

[0074] The third three-way valve (7) uses oxalic acid reagent as the control object to eliminate phosphate interference. The third three-way valve (7) is connected to the air pump (4) and the second metering tube (13) respectively.

[0075] The fourth three-way valve (8) uses ascorbic acid reagent as the control object to reduce silicomolybdenum yellow to silicomolybdenum blue. The fourth three-way valve (8) is connected to the air pump (4) and the third metering tube (15) respectively.

[0076] The fifth three-way valve (9) is used to control the collection of the mixed liquid and to combine the flow paths of the three reagents. The fifth three-way valve (9) is connected to the first metering tube (11), the second metering tube (13), the third metering tube (15), and the sixth three-way valve (10), respectively.

[0077] The sixth three-way valve (10) is controlled by the distribution of the mixed liquid and is used for selection detection or waste discharge. The sixth three-way valve (10) is connected to the main three-way valve (22).

[0078] The main three-way valve (22) is controlled by the final flow path selection and is used to switch to the luminescent dish (17) or the waste liquid pipe. The main three-way valve (22) is connected to the luminescent dish (17) or the drain pump (23) respectively depending on whether it is switched to the luminescent dish (17) or the waste liquid pipe.

[0079] (iv) The first measuring tube (11), the second measuring tube (13), and the third measuring tube (15) constitute a measuring system; wherein, the first measuring tube (11) has an accuracy of ±0.01mL and is used to quantify ammonium molybdate reagent, which is a colorimetric agent, and is quantified using the first liquid level sensor (12) as a feedback component; the second measuring tube (13) has an accuracy of ±0.01mL and is used to quantify dilute sulfuric acid, which is used to eliminate phosphate interference, and is quantified using the second liquid level sensor (14) as a feedback component; the third measuring tube (15) has an accuracy of ±0.01mL and is used to quantify alkaline luminescent agent, which is a reducing agent, and is quantified using the third liquid level sensor (16) as a feedback component; wherein, the first liquid level sensor (12), the second liquid level sensor (14), and the third liquid level sensor (16) are all photoelectric pairs;

[0080] (V) The light-emitting dish (17), photomultiplier tube (19), and circuit board (18) constitute an optical detection system; wherein, the light-emitting dish (17) is made of quartz glass and is used as a silicon molybdenum blue color reaction container, and is connected to the main three-way valve (22) and the exhaust pipe (20) respectively, for liquid inlet and exhaust outlet respectively; the photomultiplier tube (19) is used to detect absorbance at 810nm wavelength and is connected to the circuit board (18) for signal amplification; the circuit board (18) is used to control valve timing, process PMT signals, calculate silicate concentration, and output the calculation results of silicate concentration to the touch screen;

[0081] (vi) A waste liquid treatment system is composed of a drainage pump (23), an overflow pipe (21), and an exhaust pipe (20); wherein, the drainage pump (23) is used to discharge waste liquid under negative pressure and is connected to the main three-way valve (22) and the overflow pipe (21) respectively; the overflow pipe (21) adopts a U-shaped liquid seal structure to prevent the liquid level from being too high and contaminating the optical system; the exhaust pipe (20) is used to balance the internal air pressure of the light-emitting dish and is equipped with a hydrophobic filter membrane for filtration to prevent aerosol contamination.

[0082] Preferably, the constant temperature device (2) is a heating module; or a Peltier semiconductor cooling chip combined with a PID algorithm is used to achieve constant temperature control of 25±0.1℃.

[0083] The silicate detection method and apparatus based on colorimetric-chemiluminescence coupling of the present invention have the following beneficial effects:

[0084] (1) Three-way valve topology network: 6 three-way valves realize 8 flow path combinations, replacing the traditional 12 solenoid valves; the flow path design scheme requires only 2 pumps and 6 three-way valves to complete the addition of all the agents, which is a low-cost and high-efficiency solution.

[0085] (2) Pneumatic precision metering: The control accuracy of the blow / suction pump + liquid level sensor reaches ±0.5%;

[0086] (3) Optical interference resistance: Oxalic acid eliminates phosphate interference, with a detection limit as low as 0.05 μg / L;

[0087] (4) Fully enclosed flow path: overflow pipe (21) + exhaust pipe (20) double protection to prevent pollution;

[0088] (5) The drug formulation and dosage ensure high measurement accuracy, ±0.75ug / L, which is more than twice that of the existing technology; good measurement repeatability, <1% across the entire range; lower detection limit, 0.1ug / L; high degree of automation and short measurement time;

[0089] (6) The design of the luminescent dish adopts a central diffusion dosing method, which can effectively improve the chemical reaction rate and enable molybdenum silicoamic acid to oxidize luminol to the maximum extent in a short time.

[0090] (7) Introducing a high-voltage self-adjustment method into traditional technology eliminates measurement errors caused by high-voltage fluctuations and drift, effectively improving measurement accuracy;

[0091] (8) Add a constant temperature device to the traditional technology to eliminate the influence of temperature changes between different water samples on the measurement results. The key is to solve the problem that the reaction rate of samples below 20℃ is so low that they cannot be detected. Attached Figure Description

[0092] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of the present invention, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0093] Figure 1 This is a flowchart of a fully automated rapid silicate detection method provided in an embodiment of the present invention;

[0094] Figure 2 This is a schematic diagram of the fully automatic rapid silicate detector provided in an embodiment of the present invention.

[0095] Figure 3 This is a schematic diagram of the fluid path connection relationship provided for an embodiment of the present invention. Detailed Implementation

[0096] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0097] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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 the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0098] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0099] The technical problems to be solved in this embodiment include:

[0100] (1) Based on the principle of chemiluminescence, the formulation and dosage of silicate measurement chemicals were optimized to meet the measurement requirements in the range of 0 to 200 ug / L.

[0101] (2) Design a luminescent dish with a self-cleaning function, especially by adding the three reagents A, B and C in different ways to improve the rate and consistency of the chemiluminescence reaction.

[0102] (3) Optimize the design of the flow path and metering method to reduce costs while accurately quantifying the dosage of samples, A, B, and C, and ensuring the consistency of the chemiluminescence reaction.

[0103] (4) The high voltage self-compensation method is adopted to solve the influence of high voltage fluctuation on signal acquisition and improve the accuracy of measurement.

[0104] (5) Design a heating system to eliminate the influence of sample temperature changes on the measurement results.

[0105] Example 1

[0106] like Figure 1 As shown, this embodiment provides a fully automated rapid silicate detection method, including:

[0107] S1, Establish a standard curve based on silicate standard solution;

[0108] In a preferred embodiment, S1 includes:

[0109] S11, Preparation of standard solutions (according to GB / T 602), including:

[0110] (1) Prepare a stock solution, wherein the stock solution includes silicate standard material and ultrapure water;

[0111] Table 1 below shows the components, specifications, concentrations, and storage conditions for preparing the stock solution.

[0112] Table 1

[0113]

[0114] (2) Perform gradient dilution (automatically completed by the instrument).

[0115] A. Concentration gradient: 0.0, 0.5, 1.0, 5.0, 10.0, 20.0, 50.0, 100.0 μg / L;

[0116] B. Dilution algorithm, as shown in formula (1):

[0117]

[0118] Among them, V add V represents the volume of stock solution added (μL); cell The volume of the luminescent dish (5.0 mL in this example) is indicated by C. target C represents the target concentration after dilution. stock The concentration before dilution is precisely controlled by the first measuring tube 11, the second measuring tube 13, and the third measuring tube 15, with an error of <±0.5%.

[0119] S12 performs automated sample introduction and detection, including:

[0120] (1) Set the instrument parameters, including color development temperature, ammonium molybdate addition amount, reaction time, dilute sulfuric acid addition amount, alkaline luminescent agent addition amount, and detection wavelength; wherein the color development temperature is set to 25.0±0.1℃, used by the constant temperature device (2) to control the reaction temperature; the ammonium molybdate addition amount is set to 1.00±0.01mL, used by the first metering tube (11) for control; the reaction time is set to 120±1s, used to control the complete formation of silicomolybdenum yellow; the dilute sulfuric acid addition amount is 0.50±0.01mL, used by the second metering tube (13) for control, to eliminate PO4. 3- Interference; the set value of the alkaline luminescent agent addition is 0.50±0.01mL, which is used to control the reduction of silicon molybdenum blue by the third metering tube (15); the set value of the detection wavelength is 810±2nm, which is used to make the photomultiplier tube (19) in the optimal response range.

[0121] (2) Perform automatic timing control, including:

[0122] 0-30s controlled sample injection: injection cup (1) → thermostat (2) → luminescent dish (17);

[0123] 31-45s Control reagent A addition: First three-way valve (5) is turned on → ammonium molybdate injection;

[0124] 46-150s controlled formation of molybdenum silica yellow: isothermal color development;

[0125] 151-165s control to eliminate interference: Second three-way valve (6) is turned on → oxalic acid injection;

[0126] 166-180s control reduction reaction: Third three-way valve (7) is turned on → ascorbic acid injection;

[0127] Absorbance detection controlled from 181 to 240 seconds: Data was collected using a photomultiplier tube (19).

[0128] S13, Signal acquisition and processing, including:

[0129] (1) Photoelectric signal conversion, wherein the output current of the photomultiplier tube (19) is as shown in equation (2):

[0130] I out =I dark +K·e -εcd (2);

[0131] Where ε represents the molar absorptivity of molybdenum blue silicoammonia, which is 22,000 L / mol·cm in this embodiment; c represents the silicate concentration in mol / L; d represents the optical path length, which is set to 1.0 cm in this embodiment; K represents the optical gain factor, which is automatically generated by circuit board 18; I dark This indicates a dark field signal.

[0132] (2) Calculate the absorbance, as shown in equation (3):

[0133]

[0134] Among them, I blank Indicates the ultrapure water blank signal, I sample The sample signal is represented by the number of measurements taken at each concentration point, and outliers are removed (Grubbs test).

[0135] S14, Fitting the standard curve, including:

[0136] (1) The standard curve is initially fitted based on the least squares regression method, as shown in equation (4):

[0137] A = a·c + b (4);

[0138] Where 'a' is the slope, representing the sensitivity, with a theoretical value ≥ 0.035 Abs / (μg / L); and 'b' is the intercept, representing the blank value, requiring |b| ≤ 0.005 Abs.

[0139] (2) Verify the fitting quality of the preliminary fitted standard curve based on the indicators and determine the curve that meets the fitting quality as the standard curve. The indicators include verifying the correlation coefficient r ≥ 0.9995 based on the Pearson test method, verifying the residual standard deviation Sres ≤ 0.002Abs based on the calculated deviation of each point, and verifying the slope RSD ≤ 1.0% based on the curves repeated 3 times.

[0140] S15, Verify and store the standard curve, including:

[0141] (1) Accuracy was verified based on spiked recovery experiments, where the spiked concentration (μg / L) and allowable recovery range are shown in Table 2.

[0142] Table 2

[0143]

[0144]

[0145] (2) Storage and retrieval curves, including:

[0146] Data is stored on the circuit board (18) and an automatic failure mechanism is embedded to provide calibration prompts, wherein the automatic failure mechanism includes a forced recalibration when the first calibration is more than 30 days old and an alarm prompt when the blank value drifts > ±0.003Abs.

[0147] S16, perform anti-interference verification, including: adding interfering substances to the standard solution and verifying the reliability of the curve. The correspondence between interfering substances, allowable concentrations, and recovery rate requirements is shown in Table 3. This example demonstrates that dilute sulfuric acid reagent (second metering tube 13) effectively eliminates 100 times the amount of PO4. 3- interference.

[0148] Table 3

[0149] Interfering substances Allowable concentration Recovery requirement phosphate (PO4 3- )]]> ≤ 200 μg / L 98-102％ Iron ions (Fe 3+ )]]> ≤ 100 μg / L 97-103％ Turbidity (NTU) ≤5.0 99-101％

[0150] Real-world application data

[0151] The performance of the samples tested in the water samples from the Qinshan Nuclear Power Plant is shown in Table 4.

[0152] Table 4

[0153] Concentration (μg / L) Measured value (μg / L) RSD (%) 0.0 0.02 - 1.0 0.98 1.2 5.0 5.03 0.8 20.0 20.1 0.5

[0154] Standard curve equation: A = 0.0367·c++0.0012(r) 2 =0.9998)

[0155] The beneficial effects of implementing step S1:

[0156] (1) Fully automated: The instrument completes the entire process from dilution to fitting autonomously;

[0157] (2) Fast: Single curve establishment takes ≤45 minutes (traditional methods require 4 hours);

[0158] (3) Precision: Detection limit 0.05 μg / L (3σ), meeting nuclear power grade requirements;

[0159] (4) Traceability: All data is encrypted and stored for 10 years (compliant with ISO 17025).

[0160] S2, based on the standard curve, perform fully automated rapid silicate concentration detection;

[0161] In a preferred embodiment, S2 includes:

[0162] S21, before sample measurement, the range is calibrated using a standard solution. At this time, the standard measurement range is achieved when the high voltage value of the photomultiplier tube (19) is set to V1.

[0163] S22, Prepare reagents A, B and C required for the fully automated rapid silicate concentration detection.

[0164] In a preferred embodiment, S22 includes:

[0165] Prepare reagent A, wherein reagent A is 2% ammonium molybdate, comprising: injecting 800 mL of silica-free water into a 1000 mL volumetric flask, adding 20 g of analytical grade ammonium molybdate, dissolving it completely, and then adding water to make up to 1000 mL.

[0166] Prepare reagent B, wherein reagent B is 4% dilute sulfuric acid, by: using a 1000mL volumetric flask, first pour in 800mL of silica-free water, then add 27mL of analytical grade concentrated sulfuric acid, and add water to make up to 1000mL.

[0167] Prepare reagent C, wherein reagent C is an alkaline luminescent agent, comprising: first pouring 800 mL of silica-free water into a graduated polyethylene reagent bottle, then adding 40 g of analytical grade NaOH granules and 0.2 g of luminescent agent, dissolving them completely, and then adding water to 1000 mL.

[0168] S23, Perform fully automated rapid silicate concentration detection based on the standard curve.

[0169] In a preferred embodiment, S23 includes:

[0170] (1) Take 80-100 mL of sample water and put it into the sample cup (1). The sample water flows into the luminescent dish (17) through the constant temperature device (2).

[0171] (2) Quantitative dosing of water samples based on a centrally diffused dosing method; including:

[0172] A. After filling the luminescent dish (17) with sample water, drain it through the overflow pipe (21). At the same time, the drain pump (23) starts running. After a few seconds, the sample water in the luminescent dish (17) is drained. At this time, the drain pump (23) stops working.

[0173] B. Excess sample water continues to enter the luminescent dish (17) and overflows. After no more water sample flows out of the overflow tube (21), the volume of sample water in the luminescent dish (17) is about 18 mL.

[0174] C. Open the main three-way valve (22) and the drain pump (23) to remove the excess sample water from the luminescent dish (17) and measure the sample water volume to approximately 15 mL.

[0175] (3) Add reagent A and reagent B sequentially to a fixed amount of sample water; including:

[0176] A. Open the suction pump (3), the second three-way valve (6) and the third three-way valve (7) to draw the reagent A into the first metering tube (11). When the first liquid level sensor (12) measures the liquid level signal, close the suction pump (3), the second three-way valve (6) and the third three-way valve (7), and open the blowing pump (4), the first three-way valve (5) and the fourth three-way valve (8) to blow a quantitative amount of reagent A (0.5 mL to 1 mL) into the luminescent dish (17).

[0177] B. After reagent A is added, close the air pump (4), the first three-way valve (5) and the fourth three-way valve (8); wait 1 second, then open the suction pump (3), the second three-way valve (6) and the third three-way valve (7) to draw reagent B into the second metering tube (13). When the second liquid level sensor (14) measures the liquid level signal, close the suction pump (3), the second three-way valve (6) and the third three-way valve (7), and open the air pump (4), the third three-way valve (6) and the fifth three-way valve (9) to blow quantitative reagent B (0.5 mL to 1 mL) into the luminescent dish (17).

[0178] (4) Preparations before the chemical reaction, lasting 30-60 seconds; including:

[0179] A. After reagent B is added, continue to blow air for a few seconds. The bubbles enter the luminescent dish (17) to stir the liquid. The air is discharged from the exhaust pipe (20). Then close the air pump (4), the third three-way valve (6) and the fifth three-way valve (9).

[0180] B. Wait for the chemical reaction to proceed for several tens of seconds. During the waiting period, the circuit board (18) continuously reads the high voltage value V2 of the photomultiplier tube (19) at certain time intervals to determine whether |V2-V1|≤3V.

[0181] If |V2-V1|≤3V, then proceed directly to the fully automated rapid silicate concentration detection step based on reagent C and the standard curve.

[0182] If |V2-V1|>3V, then high voltage feedback self-adjustment is performed until |V2-V1|≤3V, and the high voltage feedback self-adjustment is completed within a few seconds;

[0183] C. After the high-pressure feedback self-adjustment is completed, open the suction pump (3), the first three-way valve (5), and the second three-way valve (6).

[0184] (5) Fully automated rapid silicate concentration detection based on reagent C and the aforementioned standard curve; including:

[0185] A. Draw the reagent C into the third metering tube (15). When the third liquid level sensor (16) measures the liquid level signal, close the suction pump (3), the first three-way valve (5) and the second three-way valve (6), and open the blowing pump (4), the third three-way valve (7) and the sixth three-way valve (10) to spray the quantitative reagent C (1mL~3mL) into the light-emitting dish (17) in a center emission manner.

[0186] B. In the luminescent dish (17), the reagent C reacts chemically with the mixed liquid and generates radiant light. The radiant light is received by the photomultiplier tube (19) and transmitted to the circuit board (18). The silicate concentration value in the sample water is obtained according to the standard curve. The entire fully automatic rapid silicate concentration detection process is completed within 2 minutes.

[0187] Example 2

[0188] like Figure 2 As shown, this embodiment provides a fully automatic rapid silicate detector for implementing the method of Embodiment 1, including:

[0189] Sample inlet cup (1), constant temperature device (2), suction pump (3), blowing pump (4), first three-way valve (5), second three-way valve (6), third three-way valve (7), fourth three-way valve (8), fifth three-way valve (9), sixth three-way valve (10), first metering tube (11), first liquid level sensor (12), second metering tube (13), second liquid level sensor (14), third metering tube (15), third liquid level sensor (16), light-emitting dish (17), circuit board (18), photomultiplier tube (19), exhaust pipe (20), overflow pipe (21), main three-way valve (22), and drain pump (23); wherein:

[0190] (i) The injection cup (1) and the constant temperature device (2) constitute the injection system. The injection cup (1) is used as the inlet of the original water sample, with a capacity of 5-50 mL, and is resistant to acid and alkali corrosion. It is connected to the constant temperature device (2) through a silicone tube. The constant temperature device (2) is used to implement constant temperature control at 25±0.1℃, thereby eliminating the influence of temperature on the colorimetric reaction.

[0191] In this embodiment, the temperature control device (2) is a heating module; or a Peltier semiconductor cooling chip combined with a PID algorithm is used to achieve constant temperature control of 25±0.1℃. In this embodiment, the volume of the luminescent dish (17) is approximately 20mL.

[0192] (ii) The suction pump (3) and the blowing pump (4) constitute a fluid drive system. The suction pump (3) is used to generate negative pressure (-80kPa) to extract the sample and is connected to the first three-way valve (5) to control the direction of sample injection. The blowing pump (4) is used to generate positive pressure (+60kPa) to drive the reagent mixing and is connected to the second three-way valve (6), the third three-way valve (7) and the fourth three-way valve (8) respectively to drive different reagents.

[0193] (III) The first three-way valve (5), the second three-way valve (6), the third three-way valve (7), the fourth three-way valve (8), the fifth three-way valve (9), the sixth three-way valve (10), and the main three-way valve (22) constitute a three-way valve array, serving as the core flow control component, wherein:

[0194] The first three-way valve (5) controls the sample flow and is used to switch the sample injection and / or cleaning path. The first three-way valve (5) is connected to the suction pump (3) and the first metering tube (11), the second metering tube (13) and the third metering tube (15) respectively.

[0195] The second three-way valve (6) uses ammonium molybdate reagent as the control object and is used to accurately add reagent A. The second three-way valve (6) is connected to the air pump (4) and the first metering tube (11) respectively.

[0196] The third three-way valve (7) uses oxalic acid reagent as the control object to eliminate phosphate interference. The third three-way valve (7) is connected to the air pump (4) and the second metering tube (13) respectively.

[0197] The fourth three-way valve (8) uses ascorbic acid reagent as the control object to reduce silicomolybdenum yellow to silicomolybdenum blue. The fourth three-way valve (8) is connected to the air pump (4) and the third metering tube (15) respectively.

[0198] The fifth three-way valve (9) is used to control the collection of the mixed liquid and to combine the flow paths of the three reagents. The fifth three-way valve (9) is connected to the first metering tube (11), the second metering tube (13), the third metering tube (15), and the sixth three-way valve (10), respectively.

[0199] The sixth three-way valve (10) is controlled by the distribution of the mixed liquid and is used for selection detection or waste discharge. The sixth three-way valve (10) is connected to the main three-way valve (22).

[0200] The main three-way valve (22) is controlled by the final flow path selection and is used to switch to the luminescent dish (17) or the waste liquid pipe. The main three-way valve (22) is connected to the luminescent dish (17) or the drain pump (23) respectively depending on whether it is switched to the luminescent dish (17) or the waste liquid pipe.

[0201] (iv) The first measuring tube (11), the second measuring tube (13), and the third measuring tube (15) constitute a measuring system; wherein, the first measuring tube (11) has an accuracy of ±0.01mL and is used to quantify ammonium molybdate reagent, which is a colorimetric reagent, and is quantified using the first liquid level sensor (12) as a feedback component; the second measuring tube (13) has an accuracy of ±0.01mL and is used to quantify dilute sulfuric acid, which is used to eliminate phosphate interference, and is quantified using the second liquid level sensor (14) as a feedback component; the third measuring tube (15) has an accuracy of ±0.01mL and is used to quantify alkaline luminescent agent, which is a reducing agent, and is quantified using the third liquid level sensor (16) as a feedback component; wherein, the first liquid level sensor (12), the second liquid level sensor (14), and the third liquid level sensor (16) are all photoelectric pairs.

[0202] (V) The light-emitting dish (17), photomultiplier tube (19), and circuit board (18) constitute an optical detection system; wherein, the light-emitting dish (17) is made of quartz glass (transmittance >99%@810nm), and is used as a silicon molybdenum blue color reaction container with an optical path of 10mm. It is connected to the main three-way valve (22) and the exhaust pipe (20) respectively, and is used for liquid inlet and exhaust outlet respectively; the photomultiplier tube (19) is of model Hamamatsu H10721-01, and is used to detect absorbance at a wavelength of 810nm with a sensitivity of 0.001Abs. It is connected to the circuit board (18) for signal amplification; the circuit board (18) is used to control valve timing (millisecond-level switching), process PMT signals, calculate silicate concentration, and output the calculation results of silicate concentration to the touch screen.

[0203] (vi) A waste liquid treatment system is composed of a drainage pump (23), an overflow pipe (21), and an exhaust pipe (20); wherein, the drainage pump (23) is used to discharge waste liquid under negative pressure (flow rate 200mL / min), and is connected to the main three-way valve (22) and the overflow pipe (21) respectively; the overflow pipe (21) adopts a U-shaped liquid seal structure to prevent the liquid level from being too high and contaminating the optical system; the exhaust pipe (20) is used to balance the internal air pressure of the light-emitting dish, and is equipped with a 0.22μm hydrophobic filter membrane for filtration to prevent aerosol contamination.

[0204] like Figure 3 The diagram shows the fluid path connection relationship. The working process of this detector includes:

[0205] 1. Sample injection stage: The suction pump (3) is started → the sample is drawn from the injection cup (1) through the constant temperature device (2) → the first three-way valve (5) leads to the first metering tube (11), the second metering tube (13) and the third metering tube (15);

[0206] 2. Reagent addition: Air pump (4) pushes:

[0207] (1) The second three-way valve (6) is opened → ammonium molybdate enters the first metering tube (11);

[0208] (2) The third three-way valve (7) is opened → dilute sulfuric acid enters the second metering tube (13);

[0209] (3) The fourth three-way valve (8) is opened → the alkaline luminescent agent enters the third metering tube (15);

[0210] 3. Mixed reaction:

[0211] (1) Fifth three-way valve (9) collects reagent → Sixth three-way valve (10) opens → Main three-way valve (22) switches to luminescent dish (17);

[0212] (2) Air pump (4) Pulsating air blowing (3Hz) to achieve turbulent mixing.

[0213] 4. Optical inspection:

[0214] LED light source (650nm) illuminates light-emitting dish (17) → Silica molybdenum blue is captured by photomultiplier tube (19) at an absorbance of 810nm → concentration is calculated by circuit board (18).

[0215] 5. Waste removal and cleaning:

[0216] (1) Switch the main three-way valve (22) to the waste liquid line → start the drain pump (23);

[0217] (2) Automatic flushing of the flow path with high-purity water (3 times)

[0218] The entire process takes less than 3 minutes, with a detection range of 0.1-200 μg / L and an RSD of less than 1.5%.

[0219] Application examples, as shown in Table 5, are partial measurement data tables.

[0220] Table 5

[0221]

[0222]

[0223] Through the above description of the embodiments, those skilled in the art can clearly understand that the above embodiments can be implemented by software, or by using software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solutions of the above embodiments can be embodied in the form of a software product. This software product can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, mobile hard drive, etc.) and includes several instructions to cause a computer device (such as a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0224] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fully automated rapid method for detecting silicate ions, characterized in that, include: S1, Establish a standard curve based on silicate standard solution; S2, based on the standard curve, perform fully automated rapid silicate concentration detection; Wherein, S1 includes: S11, Preparation of standard solutions; S12 performs automatic sample introduction and detection; S13, Signal Acquisition and Processing; S14, Fitting the standard curve; S15, Verify and store the standard curve; S16, Perform anti-interference verification, including: adding interfering substances to the standard solution to verify the reliability of the curve; S2 includes: S21, before sample measurement, use a standard solution to calibrate the range. At this time, the standard measurement range is achieved when the high voltage value of the photomultiplier tube (19) is set to V1. S22, Prepare reagents A, B, and C required for the fully automated rapid silicate concentration detection; reagent A is 2% ammonium molybdate; reagent B is 4% dilute sulfuric acid; and reagent C is an alkaline luminescent agent. S23, Perform fully automated rapid silicate concentration detection based on the aforementioned standard curve; S23 includes: (1) Take 80~100mL of sample water and put it into the sample cup (1). The sample water flows into the luminescent dish (17) through the constant temperature device (2). (2) Quantitative dosing of water samples based on a centrally diffused dosing method; including: A. After filling the luminescent dish (17) with sample water, drain it through the overflow pipe (21). At the same time, the drain pump (23) starts running. After a few seconds, the sample water in the luminescent dish (17) is drained. At this time, the drain pump (23) stops working. B. Excess sample water continues to enter the luminescent dish (17) and overflows. After no more water sample flows out of the overflow tube (21), the volume of sample water in the luminescent dish (17) is 18 mL. C. Open the main three-way valve (22) and the drain pump (23) to remove the excess sample water from the luminescent dish (17) and measure the sample water volume to 15 mL; (3) Add reagent A and reagent B sequentially to a fixed amount of sample water; including: A. Open the suction pump (3), the second three-way valve (6) and the third three-way valve (7) to draw the reagent A into the first metering tube (11). After the first liquid level sensor (12) measures the liquid level signal, close the suction pump (3), the second three-way valve (6) and the third three-way valve (7), and open the blowing pump (4), the first three-way valve (5) and the fourth three-way valve (8) to blow a quantitative amount of reagent A 0.5 mL to 1 mL into the luminescent dish (17). B. After reagent A is added, close the air pump (4), the first three-way valve (5) and the fourth three-way valve (8); wait 1 second, open the suction pump (3), the second three-way valve (6) and the third three-way valve (7) to draw reagent B into the second metering tube (13). When the second liquid level sensor (14) measures the liquid level signal, close the suction pump (3), the second three-way valve (6) and the third three-way valve (7), open the air pump (4), the third three-way valve (7) and the fifth three-way valve (9) to blow 0.5 mL to 1 mL of quantitative reagent B into the luminescent dish (17); (4) Preparation before the chemical reaction, lasting 30-60 seconds; including: A. After reagent B is added, continue to blow air for a few seconds. The bubbles enter the luminescent dish (17) to stir the liquid. The air is discharged from the exhaust pipe (20). Then close the air pump (4), the third three-way valve (7) and the fifth three-way valve (9). B. Wait for the chemical reaction to proceed for several tens of seconds. During the waiting process, the circuit board (18) continuously reads the high voltage value V2 of the photomultiplier tube (19) at certain time intervals to determine whether |V2-V1|≤3V. If |V2-V1|≤3V, then proceed directly to the fully automated rapid silicate concentration detection step based on reagent C and the standard curve. If |V2-V1|>3V, then high voltage feedback self-adjustment is performed until |V2-V1|≤3V, and the high voltage feedback self-adjustment is completed within a few seconds; C. After the high-pressure feedback self-adjustment is completed, open the suction pump (3), the first three-way valve (5), and the second three-way valve (6); (5) Fully automated rapid silicate concentration detection based on reagent C and the standard curve; including: A. Draw the reagent C into the third metering tube (15). When the third liquid level sensor (16) measures the liquid level signal, close the suction pump (3), the first three-way valve (5) and the second three-way valve (6), and open the blowing pump (4), the third three-way valve (7) and the sixth three-way valve (10). Spray 1 mL to 3 mL of the quantitative reagent C into the light-emitting dish (17) in a center emission manner. B. In the luminescent dish (17), the reagent C reacts chemically with the mixed liquid to generate radiant light, which is received by the photomultiplier tube (19) and transmitted to the circuit board (18). The silicate concentration value in the sample water is obtained according to the standard curve.

2. The fully automated rapid silicate detection method according to claim 1, characterized in that, S11 includes: (1) Prepare a stock solution, wherein the stock solution includes silicate standard material and ultrapure water; (2) A concentration gradient dilution is performed based on a dilution algorithm, wherein the concentration gradient is: 0.0, 0.5, 1.0, 5.0, 10.0, 20.0, 50.0, 100.0 μg / L; the dilution algorithm is shown in formula (1): （1）; in, This indicates the volume of stock solution added, in μL. Indicates the volume of the light-emitting dish. This is the target concentration after dilution; This indicates the concentration before dilution.

3. The fully automated rapid silicate detection method according to claim 2, characterized in that, S12 includes: (1) Set the instrument parameters, which include color development temperature, amount of ammonium molybdate added, reaction time, amount of dilute sulfuric acid added, amount of alkaline luminescent agent added, and detection wavelength; wherein the color development temperature is set to 25.0±0.1℃, which is used by the constant temperature device (2) to control the reaction temperature; the amount of ammonium molybdate added is set to 1.00±0.01 mL, which is used by the first metering tube (11) to control; the reaction time is set to 120±1 s, which is used to control the complete formation of silicomolybdenum yellow; the amount of dilute sulfuric acid added is 0.50±0.01 mL, which is used by the second metering tube (13) to control and eliminate PO4³⁻ interference; the amount of alkaline luminescent agent added is set to 0.50±0.01 mL, which is used by the third metering tube (15) to control the reduction of silicomolybdenum blue; the detection wavelength is set to 810±2 nm, which is used to make the photomultiplier tube (19) in the optimal response range; (2) Perform automatic timing control.

4. The fully automated rapid silicate detection method according to claim 3, characterized in that, S13 includes: (1) Photoelectric signal conversion, wherein the output current of the photomultiplier tube (19) is as shown in equation (2): （2）； in, Indicates the molar absorptivity of molybdenum blue; This indicates the silicate concentration, expressed in mol / L. Indicates optical path length; Indicates the optical gain factor; Indicates a dark field signal; (2) Calculate the absorbance, as shown in equation (3): （3）; in, This indicates the ultrapure water blank signal. This represents the sample signal.

5. The fully automated rapid silicate detection method according to claim 4, characterized in that, S14 includes: (1) The standard curve is initially fitted based on the least squares regression method, as shown in equation (4): （4）； in, The slope represents the sensitivity, with a theoretical value ≥ 0.035 Abs / (μg / L); Let | be the intercept, representing blank values, and | be | |≤0.005 Abs; (2) Verify the fitting quality of the preliminary fitted standard curve based on the indicators and determine the curve that meets the fitting quality as the standard curve. The indicators include verifying the correlation coefficient r ≥ 0.9995 based on the Pearson test method, verifying the residual standard deviation Sres ≤ 0.002 Abs based on the calculation of the deviation of each point, and verifying the slope RSD ≤ 1.0% based on the curve of repeated 3 times.

6. The fully automated rapid silicate detection method according to claim 5, characterized in that, S15 includes: (1) Accuracy verification based on spiked recovery experiments; (2) Store and recall curves, including: Data is stored on the circuit board (18) and an automatic failure mechanism is embedded to provide calibration prompts, wherein the automatic failure mechanism includes a forced recalibration when the first calibration is more than 30 days old and an alarm prompt when the blank value drifts > ±0.003 Abs.

7. The fully automated rapid silicate detection method according to claim 6, characterized in that, S22 includes: Prepare reagent A by: adding 800 mL of silica-free water to a 1000 mL volumetric flask, adding 20 g of analytical grade ammonium molybdate, dissolving it completely, and then adding water to bring the volume to 1000 mL. Prepare reagent B by: first pouring 800 mL of silica-free water into a 1000 mL volumetric flask, then adding 27 mL of analytical grade concentrated sulfuric acid, and finally adding water to bring the volume to 1000 mL. Prepare reagent C by: first pouring 800 mL of silica-free water into a graduated polyethylene reagent bottle, then adding 40 g of analytical grade NaOH granules and 0.2 g of luminescent agent, dissolving them completely, and then adding water to 1000 mL.

8. A fully automatic rapid silicate detector, used to implement the method according to any one of claims 1-7, characterized in that, include: Sample inlet cup (1), constant temperature device (2), suction pump (3), blowing pump (4), first three-way valve (5), second three-way valve (6), third three-way valve (7), fourth three-way valve (8), fifth three-way valve (9), sixth three-way valve (10), first metering tube (11), first liquid level sensor (12), second metering tube (13), second liquid level sensor (14), third metering tube (15), third liquid level sensor (16), light-emitting dish (17), circuit board (18), photomultiplier tube (19), exhaust pipe (20), overflow pipe (21), main three-way valve (22), and drain pump (23); among which: (i) The injection cup (1) and the constant temperature device (2) constitute the injection system. The injection cup (1) is used as the inlet of the original water sample, with a capacity of 5-50 mL, and is resistant to acid and alkali corrosion. It is connected to the constant temperature device (2) through a silicone tube. The constant temperature device (2) is used to implement constant temperature control at 25±0.1℃, thereby eliminating the influence of temperature on the colorimetric reaction. (ii) The suction pump (3) and the blowing pump (4) constitute a fluid drive system. The suction pump (3) is used to generate negative pressure to extract the sample and is connected to the first three-way valve (5) to control the direction of sample injection. The blowing pump (4) is used to generate positive pressure to drive the reagent mixing and is connected to the second three-way valve (6), the third three-way valve (7) and the fourth three-way valve (8) respectively to drive different reagents. (iii) The first three-way valve (5), the second three-way valve (6), the third three-way valve (7), the fourth three-way valve (8), the fifth three-way valve (9), the sixth three-way valve (10), and the main three-way valve (22) constitute a three-way valve array, serving as the core flow control component, wherein: The first three-way valve (5) controls the sample flow and is used to switch the sample injection and / or cleaning path. The first three-way valve (5) is connected to the suction pump (3) and the first metering tube (11), the second metering tube (13) and the third metering tube (15) respectively. The second three-way valve (6) uses ammonium molybdate reagent as the control object and is used to accurately add reagent A. The second three-way valve (6) is connected to the air pump (4) and the first metering tube (11) respectively. The third three-way valve (7) uses oxalic acid reagent as the control object to eliminate phosphate interference. The third three-way valve (7) is connected to the air pump (4) and the second metering tube (13) respectively. The fourth three-way valve (8) uses ascorbic acid reagent as the control object to reduce silicomolybdenum yellow to silicomolybdenum blue. The fourth three-way valve (8) is connected to the air pump (4) and the third metering tube (15) respectively. The fifth three-way valve (9) is used to control the collection of the mixed liquid and to combine the flow paths of the three reagents. The fifth three-way valve (9) is connected to the first metering tube (11), the second metering tube (13), the third metering tube (15), and the sixth three-way valve (10), respectively. The sixth three-way valve (10) is controlled by the distribution of the mixed liquid and is used for selection detection or waste discharge. The sixth three-way valve (10) is connected to the main three-way valve (22). The main three-way valve (22) is controlled by the final flow path selection and is used to switch to the luminescent dish (17) or the waste liquid pipe. The main three-way valve (22) is connected to the luminescent dish (17) or the drain pump (23) respectively depending on whether it is switched to the luminescent dish (17) or the waste liquid pipe. (iv) The first measuring tube (11), the second measuring tube (13), and the third measuring tube (15) constitute a measuring system; wherein, the first measuring tube (11) has an accuracy of ±0.01 mL and is used to quantify ammonium molybdate reagent, which is a colorimetric reagent, and is quantified using the first liquid level sensor (12) as a feedback component; the second measuring tube (13) has an accuracy of ±0.01 mL and is used to quantify dilute sulfuric acid, which is used to eliminate phosphate interference, and is quantified using the second liquid level sensor (14) as a feedback component; the third measuring tube (15) has an accuracy of ±0.01 mL and is used to quantify alkaline luminescent agent, which is a reducing agent, and is quantified using the third liquid level sensor (16) as a feedback component; wherein, the first liquid level sensor (12), the second liquid level sensor (14), and the third liquid level sensor (16) are all photoelectric pairs; (V) The light-emitting dish (17), photomultiplier tube (19) and circuit board (18) constitute an optical detection system; wherein, the light-emitting dish (17) is made of quartz glass and is used as a silicon molybdenum blue color reaction container, and is connected to the main three-way valve (22) and the exhaust pipe (20) respectively, for liquid inlet and exhaust outlet respectively; the photomultiplier tube (19) is used to detect absorbance at 810nm wavelength and is connected to the circuit board (18) for signal amplification; the circuit board (18) is used to control valve timing, process PMT signal, calculate silicate concentration and output the calculation result of silicate concentration to touch screen; (vi) A waste liquid treatment system is formed by a drainage pump (23), an overflow pipe (21) and an exhaust pipe (20); wherein, the drainage pump (23) is used to discharge waste liquid under negative pressure and is connected to the main three-way valve (22) and the overflow pipe (21) respectively; the overflow pipe (21) adopts a U-shaped liquid seal structure to prevent the liquid level from being too high and contaminating the optical system; the exhaust pipe (20) is used to balance the internal air pressure of the light-emitting dish and is equipped with a hydrophobic filter membrane for filtration to prevent aerosol contamination.

9. The fully automatic rapid silicate detector according to claim 8, characterized in that, The constant temperature device (2) is a heating module; or a Peltier semiconductor cooling chip combined with a PID algorithm is used to achieve constant temperature control of 25±0.1℃.

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