Water quality detection system and method

Abstract

The invention relates to the field of water quality detection, and discloses a water quality detection system and method.The system comprises a sampling subsystem, a dosing subsystem, a total organic carbon detection subsystem and a controller, and the sampling subsystem comprises an absorbance detection module used for detecting the absorbance of a water body to be detected; the dosing subsystem comprises an acid dosing module which is used for injecting an acid into the water body to be detected; the total organic carbon detection subsystem comprises an oxidation module, a first conductivity detection module and a second conductivity detection module, and the first conductivity detection module and the second conductivity detection module are respectively used for detecting the first conductivity and the second conductivity of a water body to be detected so as to obtain the total carbon content and the inorganic carbon content; and the controller controls the ultraviolet lamps of the first irradiation part and the second irradiation part of the oxidation module according to the absorbance. The device can automatically control the oxidation capacity of water bodies with different concentrations, well adapts to the water body concentration change, reduces the detection cost while meeting the oxidation conditions, and has high continuous use benefits.

Description

Technical Field

[0001] This invention relates to the field of water quality testing technology, and more specifically, to a water quality testing system and method. Background Technology

[0002] Water quality testing systems are widely used for testing surface water, tap water, sewage, seawater, hydrogen peroxide, and industrial water. A key component of these systems is the total organic carbon (TOC) content, which comprehensively assesses the degree of organic pollution in the water. Water quality testing systems are commonly used in environmental monitoring, urban water supply and drainage, disease control, and chemical and power industries. However, these fields often face the challenge of large fluctuations in water concentration, which can lead to insufficient or excessive oxidation capacity in the oxidation module of the TOC detection subsystem. Insufficient oxidation results in the module failing to fully oxidize the organic carbon, leading to significant deviations in the measured TOC content. To meet oxidation requirements, a common method is to add a fixed dose of oxidant to the oxidation module. However, this method can easily lead to oxidant overload, wasting oxidant and increasing testing costs. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a water quality testing system and method that can automatically control the oxidation capacity of water samples with different concentrations. It is well-suited to water samples with large concentration variations, and while meeting oxidation conditions and ensuring accurate detection of total organic carbon content, it minimizes oxidation energy consumption, reduces testing costs, and offers high continuous efficiency.

[0004] The technical solution adopted in this invention is as follows:

[0005] An embodiment of the present invention provides a water quality testing system, including a sampling subsystem comprising an absorbance detection module for detecting the absorbance of the water sample entering the sampling subsystem; a dosing subsystem comprising an acid dosing module for injecting an acid into the water sample output from the sampling subsystem to adjust the pH value of the water sample; and a total organic carbon (TOC) detection subsystem comprising an oxidation module, a first conductivity detection module, and a second conductivity detection module. The oxidation module includes two irradiation units connected in series, a first irradiation unit and a second irradiation unit, each corresponding to an ultraviolet lamp. The inlet of the first irradiation unit is connected to the outlet of the dosing subsystem, and the outlet of the second irradiation unit is connected to the inlet of the first conductivity detection module. The first conductivity detection module is used to detect the first conductivity of the water body to be tested output by the oxidation module, and the second conductivity detection module is used to detect the second conductivity of the water body to be tested output by the dosing subsystem. The first conductivity is used to calculate the total carbon content of the water body to be tested, and the second conductivity is used to calculate the inorganic carbon content of the water body to be tested. The controller controls the activation status of the ultraviolet lamps of the first and second irradiation units and the magnitude of the ultraviolet lamp current according to the absorbance of the water body to be tested.

[0006] In addition, the water quality testing system proposed according to the present invention may also have the following additional technical features:

[0007] According to one embodiment of the present invention, the sampling subsystem further includes a filter and a DC pump, the inlet of the DC pump being connected to the filter, and the outlet of the DC pump being connected to the inlet of the absorbance detection module.

[0008] According to one embodiment of the present invention, the absorbance detection module includes an overflow pool and an ultraviolet LED and photodiode detection assembly disposed at the outlet of the overflow pool. The ultraviolet LED and the photodiode detection assembly are used to detect the ultraviolet absorbance of the water body to be tested.

[0009] According to one embodiment of the present invention, the ultraviolet LED is an LED chip with an emission wavelength of 254±10nm, and the photodiode detection component includes a deep ultraviolet photodiode chip.

[0010] According to one embodiment of the present invention, the first conductivity detection module includes a total carbon transmembrane mass transfer module and a total carbon conductivity cell. The sample inlet of the total carbon transmembrane mass transfer module is connected to the outlet of the oxidation module, and the pure water outlet of the total carbon transmembrane mass transfer module is connected to the total carbon conductivity cell.

[0011] According to one embodiment of the present invention, a pure water subsystem is further included, which includes a pure water box and a constant flow pump, wherein the outlet of the pure water box is connected to the inlet of the constant flow pump, and the outlet of the constant flow pump is connected to the pure water inlet of the total carbon transmembrane mass transfer module.

[0012] According to one embodiment of the present invention, a peristaltic pump is further provided between the dosing subsystem and the sampling subsystem. The dosing subsystem further includes a first three-way valve. The inlet of the peristaltic pump is connected to the outlet of the sampling subsystem, the outlet of the peristaltic pump is connected to the first inlet of the first three-way valve, the second inlet of the first three-way valve is connected to the acid dosing module, and the outlet of the first three-way valve is connected to the oxidation module. The controller is also used to control the flow rate of the peristaltic pump.

[0013] According to one embodiment of the present invention, the total organic carbon detection subsystem includes an extension coil, the inlet of which is connected to the second outlet of the second three-way valve, and the outlet of which is connected to the second conductivity detection module.

[0014] An embodiment of the present invention proposes a water quality detection method based on the water quality detection system of the above embodiment, comprising the following steps: S1, the controller acquires the absorbance of the water body to be tested; S2, when the absorbance of the water body to be tested is less than or equal to an absorbance threshold, the controller activates the ultraviolet lamp of the first irradiation unit or the second irradiation unit and controls its current to a first preset current; when the absorbance of the water body to be tested is greater than the absorbance threshold, the controller activates the ultraviolet lamps of the first irradiation unit and the second irradiation unit and controls the current of the two ultraviolet lamps to a second preset current, the second preset current being greater than or equal to the first preset current; S3, the first conductivity detection module and the second conductivity detection module respectively detect the first conductivity of the water body to be tested output by the oxidation module and the second conductivity of the water body to be tested output by the dosing subsystem; the first conductivity is used to calculate the total carbon content of the water body to be tested, and the second conductivity is used to calculate the inorganic carbon content of the water body to be tested.

[0015] According to one embodiment of the present invention, a peristaltic pump is further provided between the dosing subsystem and the sampling subsystem. The inlet of the peristaltic pump is connected to the outlet of the sampling subsystem, and the outlet of the peristaltic pump is connected to the outlet of the dosing subsystem. In step S2, when the absorbance of the water body to be tested is less than or equal to the absorbance threshold, the controller activates the ultraviolet lamp of the first irradiation unit or the second irradiation unit and controls its current to a first preset current, and controls the flow rate of the peristaltic pump to a first preset flow rate. When the absorbance of the water body to be tested is greater than the absorbance threshold, the controller activates the ultraviolet lamps of the first irradiation unit and the second irradiation unit and controls the current of the two ultraviolet lamps to a second preset current, and controls the flow rate of the peristaltic pump to a second preset flow rate, wherein the second preset flow rate is less than or equal to the first preset flow rate.

[0016] The beneficial effects of this invention are:

[0017] The water quality testing system of the present invention configures two series-connected first and second irradiation units in the oxidation module, with each irradiation unit corresponding to a UV lamp. A controller is set up to control the UV lamp current of the first and second irradiation units according to the absorbance of the water to be tested. This allows for automated control of the oxidation capacity of the water to be tested at different concentrations. Moreover, it eliminates the need for additional injection of oxidant to meet the oxidation requirements. Compared with delaying the increase or decrease of the oxidant dosage in the oxidation module, the control of the UV lamp current is more timely and can better adapt to water bodies with large concentration variations.

[0018] When the concentration of the water being tested is high, the absorbance measured by the absorbance detection module will be too high. The controller can meet the oxidation requirements of high-concentration water by selecting to turn on the UV lamps of both irradiation units, increasing the UV lamp current of the irradiation unit that is already activated, or turning on the UV lamps of both irradiation units and increasing their UV lamp currents, without needing to add additional oxidant to ensure the oxidation effect. When the concentration of the water being tested is low, the absorbance measured by the absorbance detection module will be too low. The controller can then control one of the UV lamps in the first or second irradiation unit to turn off, or reduce the UV lamp current. This allows for meeting the oxidation conditions and ensuring accurate detection of total organic carbon content while minimizing oxidation energy consumption, reducing detection costs, and providing high continuous efficiency. Attached Figure Description

[0019] Figure 1 This is a block diagram of a water quality testing system according to an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of a water quality testing system according to an embodiment of the present invention;

[0021] Figure 3 This is a flowchart of a water quality testing method according to an embodiment of the present invention;

[0022] Explanation of the labels in the diagram:

[0023] 10. Sampling Subsystem; 11. Absorbance Detection Module; 11a. Overflow Pool; 11b. Ultraviolet LED; 11c. Photodiode Detection Component; 12. Filter; 13. DC Pump; 20. Dosing Subsystem; 21. Acid Dosing Module; 30. Total Organic Carbon Detection Subsystem; 31. Oxidation Module; 31a. First Irradiation Unit; 31b. Second Irradiation Unit; 32. First Conductivity Detection Module; 32a. Total Carbon Transmembrane Mass Transfer Module; 32b. Total Carbon Conductivity Cell; 33. Second Conductivity Detection Module; 33a. Inorganic Carbon Transmembrane Mass Transfer Module; 33b. Inorganic Carbon Conductivity Cell; 34. Extension Coil; 40. Controller; 50. Peristaltic Pump; 60. Pure Water Subsystem; 61. Pure Water Box; 62. Constant Flow Pump. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0025] like Figure 1 and Figure 2As shown, the water quality testing system of this embodiment includes: a sampling subsystem 10, a dosing subsystem 20, a total organic carbon (TOC) detection subsystem 30, and a controller 40. The sampling subsystem 10 includes an absorbance detection module 11, which detects the absorbance of the water entering the sampling subsystem 10. The dosing subsystem 20 includes an acid dosing module 21, which injects an acid into the water output from the sampling subsystem 10 to adjust the pH value of the water, ensuring that the pH value of the water meets the detection requirements after mixing with the acid in the dosing subsystem 20. The TOC detection subsystem 30 includes an oxidation module 31, a first conductivity detection module 32, and a second conductivity detection module 33. The oxidation module 31 includes two irradiation units 31a and 31b connected in series. Each irradiation unit... Each part corresponds to an ultraviolet lamp. The inlet of the first irradiation unit 31a is connected to the outlet of the dosing subsystem 20, and the outlet of the second irradiation unit 31b is connected to the inlet of the first conductivity detection module 32. After the water body to be tested passes through the oxidation module 31, the organic carbon in the water body can be oxidized into inorganic carbon. The first conductivity detection module 32 is used to detect the first conductivity of the water body to be tested output by the oxidation module 31, and the second conductivity detection module 33 is used to detect the second conductivity of the water body to be tested output by the dosing subsystem 20. The first conductivity is used to calculate the total carbon content of the water body to be tested, and the second conductivity is used to calculate the inorganic carbon content of the water body to be tested, thereby calculating the total organic carbon content of the water body to be tested. The controller 40 controls the activation status of the ultraviolet lamps of the first irradiation unit 31a and the second irradiation unit 31b and the magnitude of the ultraviolet lamp current according to the absorbance of the water body to be tested. The acid dosing module 21 may include an acid box and an injection device. Those skilled in the art can select the acid and determine the injection flow rate according to specific needs. For example, 30% phosphoric acid may be used as the acid and the injection flow rate may be 4 μL / min. This embodiment does not impose any limitations.

[0026] Specifically, after the first conductivity detection module 32 and the second conductivity detection module 33 detect the first conductivity and the second conductivity of the water body to be tested, they can plot the first conductivity curve and the second conductivity curve with time as the abscissa and conductivity as the ordinate. The peaks on the curves are integrated, and the peak areas of the same residence time on the two curves are subtracted, with the difference recorded as the total organic carbon peak area. The total organic carbon concentration is then calculated according to the "concentration-peak area" standard curve, such as the "concentration-peak area" standard curve prepared by oxidizing potassium hydrogen phthalate at a known concentration obtained experimentally. The specific calculation module can be directly set in the total organic carbon detection subsystem 30 to calculate the total organic carbon of the water body to be tested in real time. Alternatively, the total organic carbon detection subsystem 30 can directly send the first conductivity and the second conductivity of the water body to the computer for remote calculation, etc. This embodiment does not impose any limitations.

[0027] Understandably, since the oxidation module 31 is equipped with two first irradiation units 31a and second irradiation units 31b connected in series, and each irradiation unit corresponds to a UV lamp, the controller 40 controls the UV lamp current of the first irradiation unit 31a and the second irradiation unit 31b according to the absorbance of the water to be tested, thereby enabling automated control of the oxidation capacity of the water to be tested for different concentrations. Moreover, compared with delaying the increase or decrease of the oxidant dosage of the oxidation module 31, the control of the UV lamp current is more timely and can better adapt to water bodies with large concentration changes. Specifically, when the concentration of the water to be tested is high, the absorbance measured by the absorbance detection module 11 will be too high. The controller 40 can select to turn on the ultraviolet lamps of the two irradiation units, increase the ultraviolet lamp current of the irradiation unit that has already turned on the ultraviolet lamp, or turn on the ultraviolet lamps of both irradiation units and increase the ultraviolet lamp current of both, to meet the oxidation requirements of the high-concentration water without having to add an extra oxidant to ensure the oxidation effect. When the concentration of the water to be tested is low, the absorbance measured by the absorbance detection module 11 will be too low. The controller 40 can then control one of the ultraviolet lamps in the first irradiation unit 31a or the second irradiation unit 31b to turn off, or reduce the ultraviolet lamp current. This way, while meeting the oxidation conditions and ensuring accurate detection of total organic carbon content, oxidation energy consumption can be minimized, detection costs can be reduced, and continuous use benefits can be high.

[0028] In one embodiment of the present invention, when the absorbance of the water to be tested is less than or equal to the absorbance threshold, it indicates that the concentration of the water to be tested is not high. The controller 40 activates the ultraviolet lamps of the first irradiation unit 31a or the second irradiation unit 31b and controls their current to a first preset current to meet the oxidation requirements of the water to be tested. When the absorbance of the water to be tested is greater than the absorbance threshold, it indicates that the concentration of the water to be tested is high. The controller 40 activates the ultraviolet lamps of the first irradiation unit 31a and the second irradiation unit 31b and controls the current of the two ultraviolet lamps to a second preset current. The second preset current is greater than or equal to the first preset current to ensure that the water to be tested can be fully oxidized. The absorbance threshold can be set based on experience or obtained through experiments. It represents a specific value that allows a single UV lamp to fully oxidize water of a corresponding concentration when using a first preset current. When the first preset current is close to the maximum operating current of the UV lamp, the second preset current can be equal to the first preset current. When the first preset current is small, the second preset current can be set to be greater than the first preset current to ensure that the water to be tested can be fully oxidized. In some other embodiments of the present invention, when the absorbance of the water to be tested is greater than the absorbance threshold, the current of the UV lamp in the first irradiation unit 31a can be controlled to be the first preset current, and the current of the UV lamp in the second irradiation unit 31b can be the second preset current or a third preset current that is less than the second preset current. This embodiment does not impose any limitations on this.

[0029] In one embodiment of the present invention, a peristaltic pump 50 may be provided between the dosing subsystem 20 and the sampling subsystem 10. The dosing subsystem 20 further includes a first three-way valve and a second three-way valve. The inlet of the peristaltic pump 50 is connected to the outlet of the sampling subsystem 10, the outlet of the peristaltic pump 50 is connected to the first inlet of the first three-way valve, the second inlet of the first three-way valve is connected to the acid dosing module, the outlet of the first three-way valve is connected to the inlet of the second three-way valve, the first outlet of the second three-way valve is connected to the oxidation module 31, and the second outlet of the second three-way valve is connected to the second conductivity detection module 33. The controller can also be used to control the flow rate of the peristaltic pump 50. Specifically, the controller can be directly electrically connected to the peristaltic pump or send control commands to the peristaltic pump wirelessly, etc., and this embodiment is not limited thereto.

[0030] When the absorbance of the water to be tested is less than or equal to the absorbance threshold, the controller 40 can also control the flow rate of the peristaltic pump 50 to a first preset flow rate; when the absorbance of the water to be tested is greater than the absorbance threshold, the controller 40 can also control the flow rate of the peristaltic pump 50 to a second preset flow rate, the second preset flow rate being less than or equal to the first preset flow rate, ensuring that the water to be tested can fully react with the acid in the dosing system when the concentration is high by reducing the flow rate. In some other embodiments of the present invention, the first preset flow rate can also be set to a lower value, so that even if the concentration of the water to be tested is high, it can still fully react with the acid in the dosing subsystem 20, in which case the second preset flow rate can also be the same as the first preset flow rate.

[0031] In one embodiment of the present invention, the sampling subsystem 10 may further include a filter 12 and a DC pump 13. The inlet of the DC pump 13 is connected to the filter 12, and the outlet of the DC pump 13 is connected to the inlet of the absorbance detection module 11, so that the water body to be tested can pass through the filter 12 and the DC pump 13 under the drive of the DC pump 13 and enter the absorbance detection module 11, thereby avoiding impurities in the water body to be tested from affecting the absorbance detection effect.

[0032] In one embodiment of the present invention, the absorbance detection module 11 may include an overflow pool 11a and an ultraviolet LED 11b and a photodiode detection component 11c disposed at the outlet of the overflow pool 11a. The overflow port of the overflow pool 11a can discharge excess water in the overflow pool 11a to ensure unobstructed water flow in the water quality monitoring system. The ultraviolet LED 11b and the photodiode detection component 11c are used to detect the ultraviolet absorbance of the water to be tested, so that the controller 40 can control the ultraviolet lamp current of the first irradiation unit 31a and the second irradiation unit 31b according to the absorbance of the water to be tested.

[0033] Preferably, the ultraviolet LED 11b can be an LED chip with an emission wavelength of 254±10nm, and the photodiode detection component 11c can include a deep ultraviolet photodiode chip, such as a Hamamatsu S1226-18BQ silicon photodiode. In some other embodiments of the present invention, other types of LED chips and photodiode chips may be used to meet actual needs, and this embodiment is not limited thereto.

[0034] It is understandable that the photodiode assembly 4 may also include an operational amplifier circuit and a microcontroller electrically connected to the deep ultraviolet photodiode chip. After receiving the light source, the deep ultraviolet photodiode chip can convert the received light signal into an electrical signal, which is then amplified by the operational amplifier circuit and input into the microcontroller. Thus, the initial light intensity of the light source and the light intensity after absorption by the liquid can be obtained. The absorbance of the water body to be tested can be calculated by the microcontroller.

[0035] In one embodiment of the present invention, the first conductivity detection module 32 may include a total carbon transmembrane mass transfer module 32a and a total carbon conductivity cell 32b. The sample inlet of the total carbon transmembrane mass transfer module 32a is connected to the outlet of the oxidation module 31, and the pure water outlet of the total carbon transmembrane mass transfer module 32a is connected to the total carbon conductivity cell 32b. This allows the water to be tested, which is output from the oxidation module 31, to enter the total carbon transmembrane mass transfer module 32a, where carbon dioxide gas molecules can be separated and dissolved in the receiving liquid (i.e., pure water) of the total carbon transmembrane mass transfer module 32a. The pure water that has received the carbon dioxide from the water to be tested flows into the total carbon conductivity cell 32b, thereby achieving accurate measurement of the total organic carbon content of the water to be tested.

[0036] In one embodiment of the present invention, the water quality detection system further includes a pure water subsystem 60, the outlet of which is connected to the pure water inlet of the total carbon transmembrane mass transfer module 32a, for providing the first conductivity detection module 32 with a receiving liquid for carbon dioxide in the water to be tested.

[0037] Specifically, the pure water subsystem 60 may include a pure water tank 61 and a constant flow pump 62, with an optional level sensor. The outlet of the pure water tank 61 is connected to the inlet of the constant flow pump 62, and the outlet of the constant flow pump 62 is connected to the pure water inlet of the total carbon transmembrane mass transfer module 32a, so that pure water can be provided to the first conductivity detection module 32 at a stable flow rate under the drive of the constant flow pump 62. The level sensor can be built into the pure water tank 61 to monitor the level of the pure water tank 61 and feed it back to the controller 40. When the controller 40 detects that the pure water level has dropped to a preset low level, it issues a prompt that the pure water is insufficient to ensure the normal operation of the water quality monitoring system.

[0038] In one embodiment of the present invention, the total organic carbon detection subsystem may further include an extension coil 34. The inlet of the extension coil 34 is connected to the second outlet of the second three-way valve, and the outlet of the extension coil is connected to the second conductivity detection module 33. The extension coil 34 is configured to balance the pipe resistance of the two branch flows, ensuring that the flow velocities of the branch flows entering the second conductivity detection module 33 and the oxidation module 31 are consistent. After the water body to be tested enters the extension coil 34 through the second outlet of the second three-way valve of the dosing subsystem 20, it ensures sufficient dissolution and dissociation of carbon dioxide while flowing within the extension coil 34. Then, the conductivity is measured in the second conductivity detection module 33, ensuring the accuracy of the conductivity measurement. The second conductivity detection module 33 may include an inorganic carbon transmembrane mass transfer module 33a and an inorganic carbon conductivity cell 33b. The sample inlet of the inorganic carbon transmembrane mass transfer module 33a is connected to the outlet of the extension coil 34, and the pure water outlet of the inorganic carbon transmembrane mass transfer module 33a is connected to the inorganic carbon conductivity cell 33b. The working principle of the inorganic carbon transmembrane mass transfer module 33a and the inorganic carbon conductivity cell 33b is similar to that of the carbon transmembrane mass transfer module 32a and the total carbon conductivity cell 32b in the first conductivity detection module 32, and will not be described in detail here.

[0039] In one embodiment of the present invention, the pure water subsystem 60 can also be used to provide pure water to the second conductivity detection module 33. In this case, the pure water subsystem 60 also includes a third three-way valve located between the constant flow pump 62, the first conductivity detection module 32, and the second conductivity detection module 33. By controlling the length of the subsequent pipes at both ends of the outlet of the three-way valve to be consistent, the total resistance of the pipes of the two branches after the third three-way valve splits the flow can be the same, so that the detection conditions of the first conductivity detection module 32 and the second conductivity detection module 33 tend to be consistent, which facilitates subsequent calculation and result processing.

[0040] In one embodiment of the present invention, the controller 40 can be remotely connected to a computer via a 485 remote communication interface to realize remote control of the water quality detection system; the controller 40 can also control the DC pump 13 of the sampling subsystem 10, the acid dosing module 21 of the dosing subsystem 20, and the constant flow pump 62 of the pure water subsystem 60 via wired or wireless means to realize the control of the flow rate of the water sample to be tested entering the overflow tank 11a, the acid injection speed, and the flow rate of the constant flow pump 62.

[0041] In a specific embodiment of the present invention, the absorbance threshold can be set to 0.5, the first preset flow rate of the peristaltic pump 50 is 1 mL / min, the second preset flow rate of the peristaltic pump 50 is 0.5 mL / min, the acid is 30% phosphoric acid by volume, the acid injection flow rate is 4 μL / min, the first preset current of the ultraviolet lamp is 10 mA, the second preset current of the ultraviolet lamp is 20 mA, the set flow rate of the constant flow pump 62 is 0.6 mL / min, and after the third three-way valve diverts the flow, the total pipe resistance of the two branches is the same, and the water flow rate is 0.3 mL / min. If the absorbance At of the water to be tested is ≤0.5, the controller 40 controls the UV lamp of the first irradiation unit 31a to start and the UV lamp of the second irradiation unit 31b to turn off, while controlling the UV lamp current of the first irradiation unit 31a to be 10mA and the flow rate of the peristaltic pump 50 to be 1mL / min; if At>0.5, the controller controls the UV lamps of the first irradiation unit 31a and the second irradiation unit 31b to start simultaneously, controlling the UV lamp current of both irradiation units to be 20mA and the flow rate of the peristaltic pump 50 to be 0.5mL / min.

[0042] Corresponding to the water quality testing system described above, this invention also proposes a water quality testing method. Since the method embodiments of this invention correspond to the system embodiments described above, details not disclosed in the method embodiments can be found in the system embodiments described above, and will not be repeated here.

[0043] like Figure 3 As shown, the water quality testing method of this invention includes the following steps:

[0044] S1, Controller 40 acquires the absorbance of the water body to be tested.

[0045] S2, when the absorbance of the water to be tested is less than or equal to the absorbance threshold, the water concentration of the water to be tested is low. The controller 40 starts the ultraviolet lamp of the first irradiation unit 31a or the second irradiation unit 31b and controls its current to the first preset current. This can reduce oxidation energy consumption as much as possible while meeting the oxidation conditions, reduce detection costs, and achieve high continuous use benefits. When the absorbance of the water to be tested is greater than the absorbance threshold, the water concentration of the water to be tested is high. The controller 40 starts the ultraviolet lamp of the first irradiation unit 31a and the second irradiation unit 31b and controls the current of the two ultraviolet lamps to the second preset current. The second preset current is greater than or equal to the first preset current to meet the oxidation requirements of high-concentration water without the need to add an additional oxidant to ensure the oxidation effect.

[0046] S3, the first conductivity detection module 32 and the second conductivity detection module 33 respectively detect the first conductivity of the water body to be tested output by the oxidation module 31 and the second conductivity of the water body to be tested output by the dosing subsystem 20; wherein, the first conductivity is used to calculate the total carbon content of the water body to be tested, and the second conductivity is used to calculate the inorganic carbon content of the water body to be tested, and then the total organic carbon content of the water body to be tested can be calculated. The specific calculation method has been described in detail in the above system embodiment, and will not be repeated here.

[0047] It should be noted that steps S1 to S3 in the water quality detection method of this embodiment can be performed cyclically. That is, the controller 40 can adjust the ultraviolet lamp current according to the absorbance of the water body to be tested in real time to cope with water bodies with large concentration changes. By controlling the ultraviolet lamp current of the first irradiation unit 31a and the second irradiation unit 31b according to the absorbance of the water body to be tested, the oxidation capacity of the water body to be tested with different concentrations can be automatically controlled. Moreover, there is no need to inject additional oxidant to meet the oxidation requirements. Compared with delaying the increase or decrease of the oxidant dosage of the oxidation module 31, the control of the ultraviolet lamp current is more timely and can better adapt to water bodies with large concentration changes.

[0048] In one embodiment of the present invention, a peristaltic pump 50 is further provided between the dosing subsystem 20 and the sampling subsystem 10. The inlet of the peristaltic pump 50 is connected to the outlet of the sampling subsystem 10, and the outlet of the peristaltic pump 50 is connected to the outlet of the dosing subsystem 20. Specifically, the setting of the outlet of the dosing subsystem 20 can be referred to the setting of the first three-way valve and the second three-way valve in the above embodiment, which will not be repeated here. In step S2, when the absorbance of the water to be tested is less than or equal to the absorbance threshold, the controller starts the ultraviolet lamp of the first irradiation unit or the second irradiation unit and controls its current to the first preset current, and controls the flow rate of the peristaltic pump 50 to the first preset flow rate; when the absorbance of the water to be tested is greater than the absorbance threshold, the controller starts the ultraviolet lamp of the first irradiation unit and the second irradiation unit and controls the current of the two ultraviolet lamps to the second preset current, and controls the flow rate of the peristaltic pump 50 to the second preset flow rate. The second preset flow rate is less than or equal to the first preset flow rate, ensuring that the water to be tested can fully react with the acid in the dosing system when the concentration is high by slowing down the flow rate. In some other embodiments of the present invention, the first preset flow rate can also be set to a lower value so that even if the concentration of the water to be tested is high, it can still react fully with the acid in the dosing subsystem 20. In this case, the second preset flow rate can also be the same as the first preset flow rate.

[0049] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. "A plurality of" means two or more, unless otherwise explicitly specified.

[0050] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0051] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0052] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0053] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as will be understood by those skilled in the art to which embodiments of the invention pertain.

[0054] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0055] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0056] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0057] Furthermore, the functional units in the various embodiments of the present invention can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0058] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A water quality testing system, characterized in that, include: A sampling subsystem includes an absorbance detection module, which is used to detect the absorbance of the water body to be tested entering the sampling subsystem; A dosing subsystem includes an acid dosing module, which is used to inject acid into the water sample output by the sampling subsystem to adjust the pH value of the water sample. A total organic carbon detection subsystem includes an oxidation module, a first conductivity detection module, and a second conductivity detection module. The oxidation module includes two irradiation units connected in series, a first irradiation unit and a second irradiation unit, each corresponding to a UV lamp. The inlet of the first irradiation unit is connected to the outlet of the dosing subsystem, and the outlet of the second irradiation unit is connected to the inlet of the first conductivity detection module. The first conductivity detection module is used to detect the first conductivity of the water sample output by the oxidation module, and the second conductivity detection module is used to detect the second conductivity of the water sample output by the dosing subsystem. The first conductivity is used to calculate the total carbon content of the water sample, and the second conductivity is used to calculate the inorganic carbon content of the water sample. The controller controls the activation status and the magnitude of the ultraviolet lamp current of the first and second irradiation units based on the absorbance of the water body to be tested.

2. The water quality testing system according to claim 1, characterized in that, The sampling subsystem also includes a filter and a DC pump. The inlet of the DC pump is connected to the filter, and the outlet of the DC pump is connected to the inlet of the absorbance detection module.

3. The water quality testing system according to claim 1 or 2, characterized in that, The absorbance detection module includes an overflow pool and an ultraviolet LED and photodiode detection assembly disposed at the outlet of the overflow pool. The ultraviolet LED and the photodiode detection assembly are used to detect the ultraviolet absorbance of the water body to be tested.

4. The water quality testing system according to claim 3, characterized in that, The ultraviolet LED is an LED chip with an emission wavelength of 254±10nm, and the photodiode detection component includes a deep ultraviolet photodiode chip.

5. The water quality testing system according to claim 1, characterized in that, The first conductivity detection module includes a total carbon transmembrane mass transfer module and a total carbon conductivity cell. The sample inlet of the total carbon transmembrane mass transfer module is connected to the outlet of the oxidation module, and the pure water outlet of the total carbon transmembrane mass transfer module is connected to the total carbon conductivity cell.

6. The water quality testing system according to claim 5, characterized in that, It also includes a pure water subsystem, which includes a pure water box and a constant flow pump. The outlet of the pure water box is connected to the inlet of the constant flow pump, and the outlet of the constant flow pump is connected to the pure water inlet of the total carbon transmembrane mass transfer module.

7. The water quality testing system according to claim 6, characterized in that, A peristaltic pump is also provided between the dosing subsystem and the sampling subsystem. The dosing subsystem further includes a first three-way valve and a second three-way valve. The inlet of the peristaltic pump is connected to the outlet of the sampling subsystem, the outlet of the peristaltic pump is connected to the first inlet of the first three-way valve, the second inlet of the first three-way valve is connected to the acid dosing module, the outlet of the first three-way valve is connected to the inlet of the second three-way valve, the first outlet of the second three-way valve is connected to the oxidation module, and the second outlet of the second three-way valve is connected to the second conductivity detection module. The controller is also used to control the flow rate of the peristaltic pump.

8. The water quality testing system according to claim 7, characterized in that, The total organic carbon detection subsystem also includes an extension coil, the inlet of which is connected to the second outlet of the second three-way valve, and the outlet of which is connected to the second conductivity detection module.

9. A water quality detection method based on the water quality detection system according to any one of claims 1 to 8, characterized in that, Includes the following steps: S1, the controller acquires the absorbance of the water body to be tested; S2, when the absorbance of the water body to be tested is less than or equal to the absorbance threshold, the controller activates the ultraviolet lamp of the first irradiation unit or the second irradiation unit and controls its current to a first preset current; when the absorbance of the water body to be tested is greater than the absorbance threshold, the controller activates the ultraviolet lamps of the first irradiation unit and the second irradiation unit and controls the current of the two ultraviolet lamps to a second preset current, the second preset current being greater than or equal to the first preset current; S3, the first conductivity detection module and the second conductivity detection module respectively detect the first conductivity of the water body to be tested output by the oxidation module and the second conductivity of the water body to be tested output by the dosing subsystem; the first conductivity is used to calculate the total carbon content of the water body to be tested, and the second conductivity is used to calculate the inorganic carbon content of the water body to be tested.

10. The water quality testing method according to claim 9, characterized in that, A peristaltic pump is also provided between the dosing subsystem and the sampling subsystem. The inlet of the peristaltic pump is connected to the outlet of the sampling subsystem, and the outlet of the peristaltic pump is connected to the outlet of the dosing subsystem. In step S2, when the absorbance of the water body to be tested is less than or equal to the absorbance threshold, the controller starts the ultraviolet lamp of the first irradiation unit or the second irradiation unit and controls its current to a first preset current, and controls the flow rate of the peristaltic pump to a first preset flow rate. When the absorbance of the water body to be tested is greater than the absorbance threshold, the controller starts the ultraviolet lamps of the first irradiation unit and the second irradiation unit and controls the current of the two ultraviolet lamps to the second preset current, and controls the flow rate of the peristaltic pump to the second preset flow rate, wherein the second preset flow rate is less than or equal to the first preset flow rate.

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