Water quality multi-parameter detection device and method for sodium hypochlorite generation system

Abstract

The invention discloses a water quality multi-parameter detection device and method for a sodium hypochlorite generation system, and relates to the technical field of water quality detection of sodium hypochlorite generation systems. According to the main technical scheme, a conductometer is arranged between a pipeline mixer and a reactor; when the sodium hypochlorite generating system is in the first state, the conductivity meter collects the softened water conductivity of the softened water; when the sodium hypochlorite generating system is in the second state, the conductivity meter collects the dilute brine conductivity and the dilute brine temperature of the dilute brine. Multiple detection and abnormal judgment of softened water conductivity, dilute brine conductivity, temperature and other parameters are expected to be achieved in a sodium hypochlorite generation system through one conductivity meter, and it is ensured that water quality abnormal conditions of softened water and brine are found in time in the sodium hypochlorite production process. And the problems of scaling and service life reduction of the electrolytic bath caused by unqualified softened water quality and substandard yield caused by unqualified dilute brine quality are prevented, so that the life cycle of equipment is effectively prolonged, and the continuity and stability of production are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of water quality detection for sodium hypochlorite generation systems, and particularly relates to a device and method for multi-parameter water quality detection of sodium hypochlorite generation systems. Background Art

[0002] Sodium hypochlorite solution has the advantages of being non-toxic, environmentally friendly and having good disinfection and sterilization performance. Sodium hypochlorite solution is usually prepared by electrolyzing dilute brine (sodium chloride solution) in a sodium hypochlorite generation system. In traditional sodium hypochlorite production systems, water quality monitoring often relies on manual sampling and analysis, which is time-consuming and laborious, and it is difficult to achieve real-time monitoring. Summary of the Invention

[0003] The purpose of the present invention is to provide a device and method for multi-parameter water quality detection of sodium hypochlorite generation systems, which solves the problems that in traditional sodium hypochlorite production systems, water quality monitoring often relies on manual sampling and analysis, is time-consuming and laborious, and it is difficult to achieve real-time monitoring.

[0004] To solve the above technical problems, the present invention adopts the following technical solutions:

[0005] In a first aspect, a device for multi-parameter water quality detection of a sodium hypochlorite generation system is provided. The detection device is used to detect water quality parameters of the sodium hypochlorite generation system. The sodium hypochlorite generation system includes a softened water valve, an electromagnetic metering pump, and a pipe mixer. The input end of the softened water valve is used to connect to a water softener, the input end of the electromagnetic metering pump is used to connect to a salt dissolving tank. The output ends of the softened water valve and the electromagnetic metering pump are both connected to the input end of the pipe mixer. The output end of the pipe mixer is used to connect to a reactor. The detection device includes a conductivity meter, which is used to be arranged between the pipe mixer and the reactor. The conductivity meter is used to collect the softened water conductivity of softened water when the sodium hypochlorite generation system is in a first state. The conductivity meter is also used to collect the dilute salt water conductivity and the dilute salt water temperature of dilute salt water when the sodium hypochlorite generation system is in a second state. Wherein, when the sodium hypochlorite generation system is in the first state, the softened water valve is in an open state, and the electromagnetic metering pump is in a closed state. When the sodium hypochlorite generation system is in the second state, both the softened water valve and the electromagnetic metering pump are in an open state. And when the conductivity meter detects the softened water conductivity, the sodium hypochlorite generation system transfers from the first state to the second state.

[0006] A further technical solution is that the detection device further includes a softened water flow meter, which is used to be arranged between the pipe mixer and the water softener. Wherein, the softened water flow meter is used to collect the softened water flow rate.

[0007] A further technical solution is that the detection device further includes a saturated brine flowmeter; the saturated brine flowmeter is used to be arranged between the pipeline mixer and the salt dissolving tank; the saturated brine flowmeter is used to collect the saturated brine flow rate.

[0008] Secondly, a method for detecting multiple water quality parameters of a sodium hypochlorite generation system is provided. The detection method is applicable to the detection device as described in the first aspect, and the detection method includes the following operations:

[0009] Initialize the sodium hypochlorite generation system so that both the softened water valve and the electromagnetic metering pump are in the closed state;

[0010] Start the sodium hypochlorite generation system and open the softened water valve to make the sodium hypochlorite generation system in the first state;

[0011] When the opening time of the softened water valve is greater than or equal to the first preset time, use a conductivity meter to collect the conductivity of the softened water at the output end of the pipeline mixer; and when the conductivity of the softened water is greater than the preset value of the softened water conductivity, generate an abnormal alarm signal for the softened water conductivity.

[0012] When the conductivity meter collects the conductivity of the softened water at the output end of the pipeline mixer, open the electromagnetic metering pump to make the sodium hypochlorite generation system in the second state;

[0013] When the opening time of the electromagnetic metering pump is greater than or equal to the second preset time, collect the softened water flow rate through the softened water flowmeter, collect the saturated brine flow rate through the saturated brine flowmeter, and collect the conductivity and temperature of the dilute brine at the output end of the pipeline mixer through the conductivity meter. And when the conductivity of the dilute brine is not within the preset normal range of the conductivity of the dilute brine, generate an abnormal alarm signal for the conductivity of the dilute brine.

[0014] A further technical solution is that the preset value of the softened water conductivity is 50 μs / cm. A further technical solution is that the preset normal range of the conductivity of the dilute brine is [0.85S t , 1.15S t ;

[0015] where S t is the estimated value of the conductivity of the dilute brine when the temperature of the dilute brine is t; t is the measured value of the temperature of the dilute brine during the electrolysis of the dilute brine.

[0016] A further technical solution is the calculation formula for the estimated value of the conductivity of the dilute brine:

[0017]

[0018] where N p is the ppm concentration of the dilute brine; S tis the estimated value of the conductivity of dilute brine at temperature t; t is the measured value of the temperature of dilute brine during the electrolysis of dilute brine.

[0019] A further technical solution is: the calculation formula for the actual value of the concentration of dilute brine:

[0020]

[0021] Among them, N p is the ppm concentration of dilute brine; ρ y is the density of saturated brine; N y is the concentration of saturated brine; Q y is the flow rate of saturated brine; ρ s is the density of softened water; Q s is the flow rate of softened water.

[0022] A further technical solution is: when the sodium hypochlorite generation system enters the second state, and the duration of the sodium hypochlorite generation system in the second state is greater than or equal to the second preset duration, the conductivity of dilute brine in each time period is obtained in real time, and when the conductivity of dilute brine in multiple consecutive time periods is not within the preset normal range of the conductivity of dilute brine, an abnormal alarm signal of the conductivity of dilute brine is generated.

[0023] A further technical solution is: the time period includes several data acquisition cycles;

[0024] The flow rate of saturated brine and the flow rate of softened water in each data acquisition cycle are obtained in real time, and the concentration of dilute brine is calculated based on the average value of each saturated brine flow rate and the average value of each softened water flow rate.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] It is expected to realize multiple detections and abnormal judgments of parameters such as the conductivity of softened water, the conductivity of dilute brine, and temperature in the sodium hypochlorite generation system through one conductivity meter, ensure the timely discovery of abnormal water quality conditions of softened water and brine during the production of sodium hypochlorite, prevent scale formation and reduced lifespan of the electrolytic cell caused by unqualified softened water quality, and problems such as unqualified product yield caused by unqualified dilute brine quality, thereby effectively extending the equipment life cycle and ensuring the continuity and stability of production. Description of the Drawings

[0027] Figure 1 is a schematic structural diagram of a multi-parameter water quality detection device for a sodium hypochlorite generation system installed on the sodium hypochlorite generation system in this embodiment;

[0028] Figure 2 is a schematic flow diagram of a multi-parameter water quality detection method for a sodium hypochlorite generation system in this embodiment;

[0029] Figure 3 This is a schematic diagram of the relationship between the ppm concentration of dilute brine and the conductivity at 25°C in this embodiment. Detailed implementation manners

[0030] The present invention will be further described below with reference to the accompanying drawings.

[0031] Embodiment 1

[0032] This embodiment provides a multi-parameter detection device for the water quality of a sodium hypochlorite generation system. As Figure 1 shown, the detection device is used to detect the water quality parameters of the sodium hypochlorite generation system. The sodium hypochlorite generation system includes a softened water valve, an electromagnetic metering pump, and a pipe mixer. The input end of the softened water valve is used to connect to a water softener, the input end of the electromagnetic metering pump is used to connect to a salt dissolving tank, the output ends of the softened water valve and the electromagnetic metering pump are both connected to the input end of the pipe mixer, and the output end of the pipe mixer is used to connect to a reactor. The detection device includes a conductivity meter, and the conductivity meter is used to be arranged between the pipe mixer and the reactor. The conductivity meter is used to collect the softened water conductivity of the softened water when the sodium hypochlorite generation system is in a first state. The conductivity meter is also used to collect the dilute brine conductivity and the dilute brine temperature of the dilute brine when the sodium hypochlorite generation system is in a second state. Wherein, when the sodium hypochlorite generation system is in the first state, the softened water valve is in an open state and the electromagnetic metering pump is in a closed state. When the sodium hypochlorite generation system is in the second state, both the softened water valve and the electromagnetic metering pump are in an open state. And when the conductivity meter detects the softened water conductivity, the sodium hypochlorite generation system transfers from the first state to the second state.

[0033] Exemplarily, during implementation, the sodium hypochlorite generation system includes a softened water valve, an electromagnetic metering pump, a pipe mixer, as well as a water softener, a salt dissolving tank, a reactor, etc. Among them, the input end of the softened water valve is connected to the output end of the water softener through a pipeline, the output end of the softened water valve is connected to the input end of the pipe mixer through a pipeline, the input end of the electromagnetic metering pump is connected to the output end of the salt dissolving tank through a pipeline, the output end of the electromagnetic metering pump is connected to the input end of the pipe mixer through a pipeline, and the output end of the pipe mixer is connected to the reactor through a pipeline. The sodium hypochlorite generation system is a device that generates sodium hypochlorite solution by electrolyzing brine. During use, first, the salt and softened water are fully dissolved to make saturated brine for storage and standby. Secondly, the saturated brine and softened water are mixed and diluted into dilute brine with a concentration of about 2-5% as the electrolyte, and the dilute brine is subjected to an electrolysis reaction to generate sodium hypochlorite solution.

[0034] The multi-parameter water quality detection device for the sodium hypochlorite generation system includes a conductivity meter, which is arranged between the pipeline mixer and the reactor. That is to say, the conductivity meter is installed on the pipeline between the pipeline mixer and the reactor to detect the temperature and conductivity of the fluid (soft water, dilute brine) flowing from the pipeline mixer to the reactor.

[0035] During use, before the sodium hypochlorite generation system is started, the soft water valve and the electromagnetic metering pump of the sodium hypochlorite generation system are both in the closed state. When the sodium hypochlorite generation system is started, the soft water valve of the sodium hypochlorite generation system is opened. At this time, when the sodium hypochlorite generation system is in the first state, the soft water in the water softener flows through the soft water valve, the pipeline mixer, and then through the conductivity meter. When the opening time of the soft water valve is greater than or equal to the first preset time (determined according to the pipeline between the water softener and the pipeline mixer and the flow rate of the soft water), the conductivity collected by the conductivity meter at this time is recorded as the conductivity of the soft water. And the softening efficiency of the resin in the water softener is judged by the conductivity of the soft water. For example, when the conductivity of the soft water is higher than the preset value of the conductivity of the soft water, it is determined that the softening efficiency of the resin in the water softener is low. At this time, the sodium hypochlorite generation system generates an abnormal alarm signal for the conductivity of the soft water and performs a resin regeneration operation.

[0036] After the conductivity meter completes the collection of the conductivity of the soft water, other mechanisms (electromagnetic metering pump, salt dissolving tank, reactor, etc.) in the sodium hypochlorite generation system enter normal operation. At this time, the electromagnetic metering pump is opened, and when the sodium hypochlorite generation system is in the second state, the soft water in the water softener flows into the pipeline mixer through the soft water valve, and the saturated brine in the salt dissolving tank flows into the pipeline mixer through the electromagnetic metering pump. After the soft water and the saturated brine in the pipeline mixer are mixed, dilute brine is formed. When the dilute brine flows through the conductivity meter during the process of flowing into the reactor, the conductivity meter collects the conductivity and temperature of the dilute brine. When the conductivity of the dilute brine is not within the preset normal range of the conductivity of the dilute brine, the sodium hypochlorite generation system generates an abnormal alarm signal for the conductivity of the dilute brine and performs corresponding operations.

[0037] It is expected to realize multiple detections and abnormal judgments of parameters such as the conductivity of soft water, the conductivity of dilute brine, and temperature in the sodium hypochlorite generation system through one conductivity meter, ensure the timely discovery of abnormal water quality conditions of soft water and brine during the production process of sodium hypochlorite, prevent problems such as electrolytic cell scaling and reduced service life caused by unqualified soft water quality, and unqualified production output caused by unqualified dilute brine quality, thereby effectively extending the equipment life cycle and ensuring the continuity and stability of production.

[0038] In this embodiment, as Figure 1 shown, the detection device further includes a soft water flow meter; the soft water flow meter is used to be arranged between the pipeline mixer and the water softener; wherein, the soft water flow meter is used to collect the soft water flow rate.

[0039] Exemplarily, during implementation, the detection device further includes a softened water flowmeter, which is arranged between the pipeline mixer and the water softener. That is to say, the input end of the softened water flowmeter is connected to the output end of the water softener through a pipeline, and the output end of the softened water flowmeter is connected to the input end of the softened water valve through a pipeline, or the input end of the softened water flowmeter is connected to the output end of the softened water valve through a pipeline, and the output end of the softened water flowmeter is connected to the input end of the pipeline mixer through a pipeline. It is expected to achieve the purpose of more accurately collecting the softened water flow rate flowing into the pipeline mixer through the softened water flowmeter.

[0040] In this embodiment, as Figure 1 shown, the detection device further includes a saturated brine flowmeter; the saturated brine flowmeter is used to be arranged between the pipeline mixer and the salt dissolving tank; the saturated brine flowmeter is used to collect the saturated brine flow rate.

[0041] Exemplarily, during implementation, the detection device further includes a saturated brine flowmeter, which is arranged between the pipeline mixer and the salt dissolving tank. That is to say, the input end of the saturated brine flowmeter is connected to the output end of the salt dissolving tank through a pipeline, and the output end of the saturated brine flowmeter is connected to the input end of the electromagnetic metering pump through a pipeline, or the input end of the saturated brine flowmeter is connected to the output end of the electromagnetic metering pump through a pipeline, and the output end of the saturated brine flowmeter is connected to the input end of the pipeline mixer through a pipeline. It is expected to achieve the purpose of more accurately collecting the saturated brine flow rate flowing into the pipeline mixer through the saturated brine flowmeter.

[0042] Embodiment 2

[0043] This embodiment provides a method for detecting multiple water quality parameters of a sodium hypochlorite generation system. The detection method is applicable to the detection device described in Embodiment 1, as Figure 2 shown, the detection method includes the following operations:

[0044] S100. Initialize the sodium hypochlorite generation system to make both the softened water valve and the electromagnetic metering pump in the closed state;

[0045] Exemplarily, during implementation, before starting the sodium hypochlorite generation system, initialize and start the sodium hypochlorite generation system, and make both the softened water valve and the electromagnetic metering pump in the closed state.

[0046] S200. Start the sodium hypochlorite generation system and open the softened water valve to make the sodium hypochlorite generation system in the first state;

[0047] Exemplarily, during the implementation process, when the sodium hypochlorite generation system is started, the softened water valve is opened, and the sodium hypochlorite generation system is in the first state. At this time, the softened water in the water softener flows into the pipeline mixer through the softened water valve and flows towards the reactor through the pipeline mixer.

[0048] S300. When the opening duration of the softened water valve is greater than or equal to the first preset duration, use a conductivity meter to collect the softened water conductivity at the output end of the pipeline mixer; and when the softened water conductivity is greater than the preset value of the softened water conductivity, generate an abnormal alarm signal for the softened water conductivity;

[0049] Exemplarily, during the implementation process, when the opening duration of the softened water valve is greater than or equal to the first preset duration, the softened water in the pipeline mixer flows through the conductivity meter and towards the reactor. At this time, the conductivity collected by the conductivity meter is used as the softened water conductivity. When the control device of the sodium hypochlorite generation system determines that the softened water conductivity is greater than (higher than) the preset value of the softened water conductivity, it is considered that the softening efficiency of the resin in the water softener is low (lower than the normal range), then an abnormal alarm signal for the softened water conductivity is generated, and the resin regeneration operation in the water softener is performed.

[0050] Among them, the first preset duration should meet the requirement of not less than the time required for the softened water of the sodium hypochlorite generation system to completely flow through the position of the conductivity meter.

[0051] In this embodiment, the preset value of the softened water conductivity is 50 μs / cm. The hardness of water mainly refers to the concentration of calcium and magnesium ions in water. When the hardness of water increases, the conductivity must also increase. Therefore, in the sodium hypochlorite preparation process flow, the conductivity data of the softened water can be used as an auxiliary determination condition for the efficiency of the water softener.

[0052] Exemplarily, during the implementation process, the conductivity of tap water shall not exceed 2000 μs / cm. Generally, the conductivity of tap water is in the range of 125 - 1250 μs / cm. After multiple experimental determinations, the softened water conductivity prepared by the water softener used in the sodium hypochlorite generation system is stable below 5 μs / cm in a brand-new state. Considering the balance of the ion exchange resin regeneration cycle of the water softener and the problem of electrolytic cell scaling caused by too high water hardness, it is more appropriate to set the preset value of the softened water conductivity to 50 μs / cm.

[0053] S400. When the conductivity meter collects the softened water conductivity at the output end of the pipeline mixer, open the electromagnetic metering pump to make the sodium hypochlorite generation system in the second state;

[0054] Exemplarily, during the implementation process, after the conductivity meter completes the collection of the softened water conductivity, other mechanisms (electromagnetic metering pump, salt dissolving tank, reactor, etc.) in the sodium hypochlorite generation system enter normal operation. At this time, the electromagnetic metering pump is turned on, and the sodium hypochlorite generation system is in the second state. The softened water in the water softener flows into the pipeline mixer through the softened water valve, and the saturated brine in the salt dissolving tank flows into the pipeline mixer through the electromagnetic metering pump. After the softened water and the saturated brine in the pipeline mixer are mixed, dilute brine is formed. The dilute brine flows through the conductivity meter and flows towards the reactor.

[0055] S500. When the opening duration of the electromagnetic metering pump is greater than or equal to the second preset duration, collect the softened water flow rate through the softened water flowmeter, the saturated brine flow rate through the saturated brine flowmeter, and the conductivity and temperature of the dilute brine at the output end of the pipeline mixer through the conductivity meter. When the conductivity of the dilute brine is not within the preset normal range of the dilute brine conductivity, generate an abnormal alarm signal for the dilute brine conductivity.

[0056] Exemplarily, during the implementation process, when the opening duration of the electromagnetic metering pump is greater than or equal to the second preset duration, the dilute brine flows through the conductivity meter, and the conductivity meter collects the conductivity and temperature of the dilute brine. When the control device of the sodium hypochlorite generation system determines that the conductivity of the dilute brine is not within the preset normal range of the dilute brine conductivity, the sodium hypochlorite generation system generates an abnormal alarm signal for the dilute brine conductivity and performs corresponding operations.

[0057] Among them, the second preset duration should satisfy the requirement of being not less than the sum of the time required for the saturated brine in the sodium hypochlorite generation system to completely flow through the position of the conductivity meter and 5 data collection cycles of the sodium hypochlorite generation system.

[0058] It is expected to achieve multiple detections and abnormal judgments of parameters such as softened water conductivity, dilute brine conductivity, and temperature in the sodium hypochlorite generation system through one conductivity meter, ensure timely detection of abnormal water quality conditions of softened water and brine during the production of sodium hypochlorite, prevent scaling and reduced lifespan of the electrolytic cell caused by unqualified softened water quality, and problems such as unqualified production due to unqualified dilute brine quality, thereby effectively extending the equipment life cycle and ensuring the continuity and stability of production.

[0059] In this embodiment, the preset normal range of the dilute brine conductivity is [0.85S t ,1.15S t ;

[0060] Exemplarily, during the implementation process, when the sodium hypochlorite generation system is operating in a steady state, the fluctuation range of the dilute brine conductivity data is usually within ±10%. Therefore, considering factors such as instrument data acquisition error and calculation error, it is more appropriate to take ±15% of the estimated value of the dilute brine conductivity as the preset value range, that is, when the value of the dilute brine conductivity monitored in real time by the sodium hypochlorite generation system is less than 0.85S t or greater than 1.15S t it is determined as abnormal dilute brine conductivity.

[0061] Among them, S t is the estimated value of the dilute brine conductivity when the temperature of the dilute brine is t; t is the measured value of the temperature of the dilute brine during electrolysis.

[0062] In this embodiment, the calculation formula for the estimated value of the dilute brine conductivity:

[0063]

[0064] Among them, N p is the ppm concentration of the dilute brine; S t is the estimated value of the dilute brine conductivity when the temperature of the dilute brine is t; t is the measured value of the temperature of the dilute brine during electrolysis.

[0065] Among them, ppm (Parts Per Million) is a unit used to represent trace concentration, meaning the number of parts per million.

[0066] In this embodiment, the calculation formula for the actual value of the dilute brine concentration:

[0067]

[0068] Among them, N p is the ppm concentration of the dilute brine; ρ y is the density of the saturated brine; N y is the concentration of the saturated brine; Q y is the flow rate of the saturated brine; ρ s is the density of the softened water; Q s is the flow rate of the softened water.

[0069] Exemplarily, during the implementation process, considering the usage scenario of the sodium hypochlorite generation system and the range of conventional electrolysis conditions, the relationship between the ppm concentration of the dilute brine in the range of 10000 - 50000 and the conductivity is mainly analyzed. Referring to the data in the literature, the relationship diagram between the ppm concentration and the conductivity of the dilute brine at 25°C is shown as Figure 3 shown.

[0070] Among them, the conductivity data range is: 17750 - 100000 μs / cm, and the salinity data range is: 10000 - 64325 ppm (i.e., 1% - 6.43% concentration). From the comprehensive analysis of the relationship graph and data, it can be known that:

[0071] At the same temperature, the greater the concentration of the brine, the greater the conductivity, showing an approximately proportional relationship.

[0072] Partial reference data of conductivity, ppm concentration of dilute brine, and percentage concentration of dilute brine are shown in Table 1:

[0073]

[0074]

[0075] Table 1

[0076] Derive its relationship formula based on the conductivity and salinity data at 25°C, and then the conductivity calculation formula at different salinities and temperatures can be obtained by combining the relationship formula between temperature and conductivity.

[0077] Since the salinity and conductivity show an approximately proportional relationship at the same temperature, the estimated formula for conductivity at 25°C is preset as follows:

[0078] S 25 = a·N p + b

[0079] Where: S 25 is the estimated value of the conductivity of dilute brine at 25°C, μs / cm; N p is the ppm concentration of dilute brine, ppm; a is the slope coefficient; b is the offset coefficient.

[0080] By analyzing the variation law of the ratio of the conductivity increment to the salinity ppm increment of all adjacent data in the data, the approximate value of the slope coefficient a in the formula can be obtained. Through a large amount of data analysis, the following conclusions can be drawn:

[0081] When the salinity ppm value is not greater than 25000, the increment ratio is almost between 1.62 and 1.63;

[0082] When the salinity ppm value is greater than 25000, the increment ratio is almost between 1.47 and 1.48.

[0083] In view of this situation, to ensure the accuracy of the estimation formula, the formula derivation is considered to be carried out in intervals.

[0084] Case ①: When Np ≤ 25000, take multiple average values to obtain the approximate value of the slope coefficient a:

[0085] a ≈ 1.626

[0086] The approximate value of the offset coefficient b is obtained by calculating the average value of the offsets of multiple groups of data:

[0087] b ≈ 1342.2

[0088] Case ②: When Np > 25000, take multiple The approximate value of the slope coefficient a is obtained by calculating the average value:

[0089] a ≈ 1.475

[0090] The approximate value of the offset coefficient b is obtained by calculating the average value of the offsets of multiple groups of data:

[0091] b ≈ 5121.5

[0092] In summary, the estimation formula for the conductivity at 25°C is as follows:

[0093]

[0094] Where S 25 is the estimated value of the conductivity of dilute brine at a temperature of 25°C, in μs / cm; N p is the ppm concentration of dilute brine, in ppm.

[0095] An increase in temperature will increase the degree of dissociation of electrolytes in water and the migration speed of ions, thus resulting in an increase in conductivity. For dilute brine, for every 1°C increase in the temperature of dilute brine, the conductivity of dilute brine increases by approximately 2%. The conductivity of dilute brine at different temperatures can be estimated by the following formula:

[0096] S t = S 25 · [1 + β(t - 25)]

[0097] Where S T is the estimated value of the conductivity of dilute brine at a temperature of t; t is the measured value of the temperature of dilute brine during electrolysis; S25 is the estimated value of the conductivity of dilute brine at a temperature of 25°C; β is the temperature correction coefficient, and β = 0.02.

[0098] The conductivity calculated by the formula is verified and compared with the original conductivity data in the data, and the verification results are as follows:

[0099] The total number of verification data is 118. Among them, the number with an absolute error within 0.2% is 118, and the number with an absolute error within 0.1% is 117. The formula can estimate the data in the original table materials quite perfectly.

[0100] After integrating the above formula with the formula for the relationship between temperature and conductivity, the calculation formula for the estimated value of the conductivity of dilute brine can be obtained as follows:

[0101]

[0102] Where S t is the estimated value of the conductivity of dilute brine at the temperature t of dilute brine, μs / cm; t is the measured value of the temperature of dilute brine during the electrolysis of dilute brine, °C; N p is the ppm concentration of dilute brine, ppm.

[0103] Among them, the concentration of the saturated brine used is about 26.5%, the density of the saturated brine is about 1.12 kg / L, and the density of softened water is taken as 1 kg / L. Then the calculation formula for the actual value of the concentration of dilute brine is:

[0104]

[0105] Simplified to:

[0106]

[0107] Referring to the experimental data, when the equipment is in a steady state operation, the fluctuation range of the conductivity data of dilute brine is usually within ±10%. Considering comprehensively the influencing factors such as the data acquisition error of the instrument and the error of the estimation formula, it is more appropriate to take ±15% of the estimated value as the normal range, that is, when the conductivity value of dilute brine monitored in real time by the system is less than 0.85S t or greater than 1.15S t it is determined as abnormal conductivity data.

[0108] In this embodiment, when the sodium hypochlorite generation system enters the second state and the duration of the sodium hypochlorite generation system in the second state is greater than or equal to the second preset duration, the conductivity of dilute brine in each time period is obtained in real time, and when the conductivity of dilute brine in multiple consecutive time periods is not within the preset normal range of the conductivity of dilute brine, an abnormal alarm signal of the conductivity of dilute brine is generated.

[0109] In this embodiment, the time period includes several data acquisition cycles; the flow rate of saturated brine and the flow rate of softened water in each data acquisition cycle are obtained in real time, and the concentration of dilute brine is calculated based on the average value of the flow rates of saturated brine and the average value of the flow rates of softened water.

[0110] Exemplarily, during the implementation process, in order to exclude misjudgment caused by fluctuations in individual data, when calculating the concentration of dilute brine, the average values of the data in 5 acquisition cycles are used for calculating the flow rates of saturated brine and softened water. When the sodium hypochlorite generation system is actually operating, each time the sodium hypochlorite generation system is started up and enters the second state, and after a second preset duration, the saturated brine has completely flowed through the position of the conductivity meter, and the system has collected at least 5 pieces of flow rate data of softened water and saturated brine. At this time, the sodium hypochlorite generation system starts to calculate and judge. When the sodium hypochlorite generation system determines that the dilute brine conductivity data is too large or too small and abnormal in 3 consecutive time periods, an alarm signal prompt for abnormal dilute brine conductivity will be initiated.

[0111] Among them, the time period includes 5 data acquisition cycles.

[0112] Example, when the average value of the saturated brine flow rate collected by the sodium hypochlorite generation system is 6.96 L / h, the average value of the softened water flow rate is 64.32 L / h, the temperature of the dilute brine is 20.5 °C, and the conductivity of the dilute brine is 41348.4 μs / cm.

[0113] Then the actual value of the dilute brine concentration:

[0114]

[0115] Substitute the actual value of the dilute brine concentration and the temperature of the dilute brine into the calculation formula of the estimated value of the dilute brine conductivity:

[0116] S t =(1.475×28645 + 5121.5)·[1 + 0.02(20.5 - 25)]≈43109

[0117] Therefore, the preset normal range of the dilute brine conductivity is [36643, 49575], and the dilute brine conductivity of 41348.4 is within the preset normal range of the dilute brine conductivity, and it is determined that the dilute brine conductivity is normal.

[0118] Although the present invention has been described herein with reference to multiple illustrative embodiments of the present invention, it should be understood that those skilled in the art can design many other modifications and embodiments that will fall within the scope of the principles and spirit disclosed in this application. More specifically, within the scope of this application's disclosure, the drawings, and the claims, various variations and improvements can be made to the components and / or the layout of the subject combination layout. In addition to the variations and improvements made to the components and / or the layout, other uses will also be apparent to those skilled in the art.

Claims

1. A water quality multi-parameter detection device for a sodium hypochlorite generation system, characterized in that The detection device is used to detect the water quality parameters of the sodium hypochlorite generation system. The sodium hypochlorite generation system includes a softened water valve, an electromagnetic metering pump, and a pipe mixer. The input end of the softened water valve is used to connect to a water softener, the input end of the electromagnetic metering pump is used to connect to a salt dissolving tank. The output ends of the softened water valve and the electromagnetic metering pump are both connected to the input end of the pipe mixer. The output end of the pipe mixer is used to connect to a reactor. The detection device includes: A conductivity meter, which is used to be arranged between the pipe mixer and the reactor. The conductivity meter is used to collect the softened water conductivity of the softened water when the sodium hypochlorite generation system is in the first state. The conductivity meter is also used to collect the diluted brine conductivity and the diluted brine temperature of the diluted brine when the sodium hypochlorite generation system is in the second state. Wherein, when the sodium hypochlorite generation system is in the first state, the softened water valve is in the open state and the electromagnetic metering pump is in the closed state. When the sodium hypochlorite generation system is in the second state, both the softened water valve and the electromagnetic metering pump are in the open state. And when the conductivity meter detects the softened water conductivity, the sodium hypochlorite generation system transfers from the first state to the second state.

2. The detection device according to claim 1, characterized in that: It further includes a softened water flowmeter. The softened water flowmeter is used to be arranged between the pipe mixer and the water softener. Wherein, the softened water flowmeter is used to collect the softened water flow rate.

3. The detection device according to claim 2, characterized in that: It further includes a saturated brine flowmeter. The saturated brine flowmeter is used to be arranged between the pipe mixer and the salt dissolving tank. The saturated brine flowmeter is used to collect the saturated brine flow rate.

4. A method for detecting multiple water quality parameters of a sodium hypochlorite generation system, characterized in that, The detection method is applicable to the detection device according to claim 3. The detection method includes the following operations: Initialize the sodium hypochlorite generation system to make both the softened water valve and the electromagnetic metering pump in the closed state. Start the sodium hypochlorite generation system and open the softened water valve to make the sodium hypochlorite generation system in the first state. When the opening time of the softened water valve is greater than or equal to the first preset time, use the conductivity meter to collect the softened water conductivity at the output end of the pipe mixer. And when the softened water conductivity is greater than the preset value of the softened water conductivity, generate an alarm signal for abnormal softened water conductivity. When the conductivity meter collects the softened water conductivity at the output end of the pipe mixer, open the electromagnetic metering pump to make the sodium hypochlorite generation system in the second state. When the opening time of the electromagnetic metering pump is greater than or equal to the second preset time, collect the softened water flow rate through the softened water flowmeter, collect the saturated brine flow rate through the saturated brine flowmeter, and collect the diluted brine conductivity and temperature at the output end of the pipe mixer through the conductivity meter. And when the diluted brine conductivity is not within the preset normal range of the diluted brine conductivity, generate an alarm signal for abnormal diluted brine conductivity.

5. The detection method according to claim 4, characterized in that: The preset value of the softened water conductivity is 50 μs / cm.

6. The detection method according to claim 4, characterized in that: The preset normal range of the dilute salt water conductivity is [0.85 S t , 1.15 S t ; Among them, S t is the estimated value of the conductivity of dilute brine when the temperature of the dilute brine is t; t is the measured value of the temperature of the dilute brine during the electrolysis of the dilute brine.

7. The detection method according to claim 6, wherein Calculation formula for estimated value of dilute brine conductivity: Among them, N p is the ppm concentration of the dilute brine; S t is the estimated value of the electrical conductivity of the dilute brine when the temperature of the dilute brine is t; t is the measured value of the temperature of the dilute brine during the electrolysis of the dilute brine.

8. The detection method according to claim 7, wherein Calculation formula for actual value of dilute brine concentration: Among them, N p is the ppm concentration of the dilute brine; ρ y is the density of the saturated brine; N y is the concentration of the saturated brine; Q y is the flow rate of the saturated brine; ρ s is the density of the softened water; Q s is the flow rate of the softened water.

9. The detection method according to claim 4, wherein: When the sodium hypochlorite generation system enters the second state and the duration of the sodium hypochlorite generation system in the second state is greater than or equal to the second preset duration, the conductivity of the dilute brine in each time period is obtained in real time, and when the conductivity of the dilute brine in a continuous plurality of time periods is not within the preset normal range of the dilute brine conductivity, an abnormal alarm signal for the dilute brine conductivity is generated.

10. The detection method according to claim 9, wherein: The time period includes a plurality of data acquisition cycles; The flow rate of the saturated brine and the flow rate of the softened water in each data acquisition cycle are obtained in real time, and the concentration of the dilute brine is calculated based on the average value of the flow rates of the saturated brine and the average value of the flow rates of the softened water.

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