CN116457647A - Water quality analysis device - Google Patents

Abstract

The present invention provides a water quality analysis device for performing a calibration operation using a calibration aqueous solution and measuring the concentration of a substance to be measured in sample water, the water quality analysis device comprising: a flow cell for flowing the sample water and the correction water solution; and a first switching unit that switches whether to supply the sample water or the correction aqueous solution to the flow cell.

Description

Water quality analysis device

Technical Field

The present invention relates to a water quality analysis device.

Background

Conventionally, a water quality analyzer having both a fluorescence measurement function and a turbidity measurement function has been known (for example, patent document 1).

Patent document 1: japanese patent No. 6436266

Disclosure of Invention

Technical problem

It is preferable that the calibration of the water quality analyzer can be easily performed.

Technical proposal

In order to solve the above-described problems, a first aspect of the present invention provides a water quality analysis device. The water quality analysis device may perform the calibration operation using the calibration aqueous solution. The water quality analyzer can measure the concentration of a substance to be measured in sample water. The water quality analysis device may be provided with a flow cell. The flow cell can flow sample water and correction water solution. The water quality analysis device may include a first switching unit. The first switching section may switch whether to supply the sample water or the correction aqueous solution to the flow cell.

The first switching part may be a three-way valve.

The water quality analysis device may be provided with a deaeration tank. The deaeration tank may remove bubbles of the sample water and supply the same to the flow cell. The first switching part may be located between the flow cell and the deaeration tank in a flow path through which the sample water flows.

The first switching part may be disposed under the flow cell in the height direction.

The first switching portion may be disposed upstream with respect to the flow cell in a flow path through which the sample water and the correction aqueous solution flow.

The water quality analysis device may include a calibration aqueous solution removal unit. The correction aqueous solution removal portion may remove the correction aqueous solution from the flow cell at the end of the correction operation.

The water quality analysis device may include a second switching unit. The second switching section may be disposed downstream with respect to the flow cell in a flow path through which the sample water and the correction aqueous solution flow. The second switching section may switch to circulate or drain the sample water or the correction aqueous solution.

The aqueous correction solution may be any one of a turbidity standard sample for turbidity correction and a fluorescence intensity standard sample for concentration correction. In the case where the correction aqueous solution is a turbidity standard sample, the second switching section may circulate the correction aqueous solution. In the case where the correction aqueous solution is a fluorescent intensity standard sample, the second switching section may discharge the correction aqueous solution.

The water quality analysis device may include a plurality of flow cells. The water quality analysis device may include a third switching unit. The third switching section may be provided between the two flow cells in a flow path through which the sample water and the correction aqueous solution flow.

The above summary of the present invention does not list all features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

Drawings

Fig. 1 is a diagram showing a water quality analysis device 100 according to an embodiment.

Fig. 2 is a diagram showing the flow path 1 of the aqueous humor analysis device 100 in detail.

Fig. 3 is a diagram showing the first switching unit 40 when turbidity or concentration of the sample water 3 is measured in the water quality analysis device 100.

Fig. 4 is a diagram showing the first switching unit 40 when turbidity correction or concentration correction is performed in the water quality analysis device 100.

Fig. 5 is a diagram showing a water quality analysis device 200 according to another embodiment.

Fig. 6 is a diagram showing the first switching unit 40 and the second switching unit 50 when turbidity or concentration of the sample water 3 is measured in the water quality analysis device 200.

Fig. 7 is a diagram showing the first switching unit 40 and the second switching unit 50 when the water quality analyzer 200 performs the concentration correction.

Fig. 8 is a diagram showing the first switching unit 40 and the second switching unit 50 when turbidity correction is performed in the water quality analysis device 200.

Fig. 9 is a diagram showing a water quality analysis device 300 according to another embodiment.

Fig. 10 is a diagram showing a water quality analysis device 400 of a comparative example.

Fig. 11 is a diagram showing a comparison between the water quality analyzer 100 of the example and the water quality analyzer 400 of the comparative example.

Fig. 12 is a diagram showing an example of the relationship between turbidity and fluorescence intensity.

Symbol description

The flow cell 1, the flow cell 2, the sample water 3, the calibration aqueous solution 4, the turbidity detection optical system 10, the turbidity detection light emitting unit 11, the turbidity detection light receiving unit 12, the turbidity detection signal processing unit 13, the fluorescence detection optical system 20, the fluorescence detection light emitting unit 21, the fluorescence detection light receiving unit 22, the fluorescence detection signal processing unit 23, the control operation unit 30, the infrared light lighting circuit 31, the excitation light lighting circuit 32, the turbidity operation unit 33, the fluorescence intensity correction unit 34, the concentration operation unit 35, the first switching unit 40, the second switching unit 42, the first switching unit 44, the second switching unit 50, the third switching unit 52, the third switching unit 54, the third switching unit 62, the fourth switching unit 64, the syringe 70, the device 80, the deaeration tank 90, the water quality analysis device 100, the water quality analysis device 200, the water quality analysis device 300, and the water quality analysis device 400.

Detailed Description

The present invention will be described below with reference to embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, all combinations of the features described in the embodiments are not necessarily essential to the embodiments of the invention.

In this specification, technical matters are sometimes described using rectangular coordinate axes of an X axis, a Y axis, and a Z axis. The rectangular coordinate axes merely determine the relative positions of the constituent elements, and do not limit the specific directions. The +Z axis direction and the-Z axis direction are directions opposite to each other. When the direction is not positive or negative, the direction is referred to as the Z-axis direction, it means a direction parallel to the +z-axis and the-Z-axis. The extending direction of the flow cell 2 is set to the Z axis. The axes orthogonal to the extending direction of the flow cell 2 are set as an X axis and a Y axis. In this specification, the direction of the Z axis is sometimes referred to as the height direction. The +z axis direction is the positive side in the height direction.

Fig. 1 is a diagram showing a water quality analysis device 100 according to an embodiment. In this example, the water quality analysis device 100 includes a flow path 1, a flow cell 2, an optical system for turbidity detection 10, an optical system for fluorescence detection 20, a signal processing unit for turbidity detection 13, a signal processing unit for fluorescence detection 23, and a control arithmetic unit 30. The control computing unit 30 includes an infrared light lighting circuit 31, an excitation light lighting circuit 32, a turbidity computing unit 33, a fluorescence intensity correcting unit 34, and a concentration computing unit 35. The turbidity detection optical system 10 and the fluorescence detection optical system 20 are optical systems of the water quality analysis device 100.

Sample water 3 flows through the flow path 1 (indicated by a single-dot chain line) and the flow cell 2. The sample water 3 contains a substance to be measured. In this example, the substance to be measured is polycyclic aromatic hydrocarbon (Polyycyclic Aromatic Hydrocarbons: hereinafter, referred to as PAH). The plurality of flow cells 2 are provided in the turbidity detection optical system 10 and the fluorescence detection optical system 20, respectively. In fig. 1, a flow cell 2 provided in an optical system for turbidity detection 10 is referred to as a flow cell 2-1. In fig. 1, the flow cell 2 provided in the fluorescence detection optical system 20 is referred to as a flow cell 2-2. Flow cell 2-1 and flow cell 2-2 are arranged in series in flow path 1. In fig. 1, sample water 3 is introduced and discharged in the direction of the arrow.

The water quality analysis device 100 measures the concentration of a substance to be measured in the sample water 3. For example, the sample water 3 is environmental water such as tap water, sewage, and seawater, or drainage water. The water quality analysis device 100 may be provided on a ship. The water quality analysis device 100 is a fluorescence detection type water quality analysis device. When a fluorescent substance such as PAH is contained in the sample water 3, if ultraviolet light (excitation light L3) is irradiated to the sample water 3, fluorescence L4 having a wavelength unique to the substance is generated. The fluorescence intensity is proportional to the concentration of the fluorescent substance contained, and therefore the concentration of the fluorescent substance can be measured with high accuracy. In this example, the water quality analysis device 100 measures the concentration of the substance to be measured based on the fluorescence intensity from the sample water 3. The fluorescence intensity is measured in the fluorescence detection optical system 20. The fluorescence intensity signal s2 is output from the fluorescence detection signal processing section 23. In this specification, the "intensity signal" is sometimes referred to simply as "intensity".

In the case where suspended substances are contained in the sample water 3, excitation light L3 and/or fluorescence L4 sometimes decay due to the influence of light scattering and/or absorption from the suspended substances (particles). This phenomenon is called the internal filtering effect. Due to the internal filter effect, in an environment where the concentration of suspended substances (hereinafter referred to as turbidity) is high, the measurement accuracy of fluorescence intensity may be deteriorated. Therefore, in order to improve the measurement accuracy of the fluorescence intensity, it is preferable to correct the fluorescence intensity according to the turbidity of the sample water 3. In this example, the water quality analyzer 100 measures both the fluorescence intensity and turbidity of the sample water 3. The water quality analysis device 100 measures turbidity of the sample water 3 based on the intensity of scattered light or transmitted light from the sample water 3. The intensity of scattered light or transmitted light of the sample water 3 is measured in the turbidity detecting optical system 10. The intensity signal s1 of the scattered light or the transmitted light of the sample water 3 is output from the turbidity detection signal processing section 13.

The infrared light-on circuit 31 is connected to the turbidity detection light-emitting portion 11 of the turbidity detection optical system 10. The infrared light lighting circuit 31 is a circuit for controlling the operation of the turbidity detecting light-emitting unit 11. The excitation light lighting circuit 32 is connected to the fluorescence detection light emitting section 21 of the fluorescence detection optical system 20. The excitation light lighting circuit 32 is a circuit for controlling the operation of the fluorescence detection light emitting section 21.

First, measurement of turbidity of the sample water 3 will be described. The turbidity detection optical system 10 includes a turbidity detection light-emitting unit 11 and a turbidity detection light-receiving unit 12. The turbidity detecting light-emitting portion 11 irradiates an infrared light L1. The turbidity detecting light emitting portion 11 irradiates the sample water 3 inside the flow cell 2-1 with infrared light L1. The turbidity detecting light-emitting unit 11 is an LED (Light Emitting Diode: light-emitting diode) or a laser irradiation device, for example.

By irradiating the sample water 3 inside the flow cell 2-1 with infrared light L1, scattered light or transmitted light (referred to as outgoing light L2) is generated. Scattered light is generated by light scattering of the sample water 3. The transmitted light is light that is not absorbed by the suspended matter of the sample water 3. The turbidity detection light receiving unit 12 receives the emitted light L2. The turbidity detection light receiving unit 12 converts the emitted light L2 into an electric intensity signal. As an example, the turbidity detecting light receiving unit 12 is a photodiode.

The turbidity detection signal processing unit 13 processes the intensity signal from the turbidity detection light receiving unit 12. The turbidity detection signal processing unit 13 can amplify the intensity signal from the turbidity detection light receiving unit 12. The turbidity detection signal processing unit 13 can remove noise from the intensity signal of the turbidity detection light receiving unit 12. The turbidity detection signal processing unit 13 processes the intensity signal from the turbidity detection light receiving unit 12, and outputs the intensity signal as a scattered light or transmitted light intensity signal s1. The intensity signal s1 of the scattered light or the transmitted light may be an intensity signal corresponding to at least one of the intensity of the scattered light and the intensity of the transmitted light.

The turbidity calculating unit 33 calculates the turbidity D1 of the sample water 3. The turbidity calculating unit 33 calculates the turbidity D1 of the sample water 3 based on the signal from the turbidity detecting signal processing unit 13. That is, the turbidity calculating unit 33 calculates the turbidity D1 of the sample water 3 based on the intensity signal s1 of the scattered light or the transmitted light. The turbidity calculating unit 33 can calculate the turbidity D1 of the sample water 3 by multiplying the intensity signal s1 of the scattered light or the transmitted light by the turbidity correction coefficient calculated by the turbidity correction. The turbidity calculation unit 33 may output the turbidity D1 to an external device or the like.

In the case of low turbidity, the intensity of scattered light is proportional to turbidity. On the other hand, when the turbidity is high, the scattered light is attenuated by the internal filter effect, and it is difficult to measure the turbidity by the intensity of the scattered light. The turbidity detection signal processing unit 13 may calculate a reference turbidity using the intensity of the transmitted light, and determine which of the intensity of the scattered light and the intensity of the transmitted light is used in the turbidity measurement based on the reference turbidity. The reference turbidity is the calculated turbidity of the pseudo design. The reference turbidity can also be calculated using the intensity of the scattered light. For example, in the case where the reference turbidity is 0 to 40FNU (in the case where the turbidity is low), the turbidity is calculated from the intensity of scattered light. In the case where the reference turbidity is 40 to 400FNU (in the case where the turbidity is high), the reference turbidity is referred to as turbidity. The FNU is one of units of turbidity. FNU is the units of the turbidity of Fulmahydrazine. The control arithmetic unit 30 may calculate the reference turbidity using the intensity of the transmitted light, and determine which of the intensity of the scattered light and the intensity of the transmitted light is used in the turbidity measurement based on the reference turbidity.

The turbidity detecting signal processing unit 13 may output the scattered light or transmitted light intensity signal s1 using both the scattered light intensity and the transmitted light intensity. For example, the intensity signal s1 of the scattered light or the transmitted light may be a ratio of the intensity of the scattered light to the intensity of the transmitted light (the intensity of the scattered light/the intensity of the transmitted light). By setting the intensity signal s1 of the scattered light or the transmitted light to be the ratio of the intensity of the scattered light to the intensity of the transmitted light, the error in the intensity of the scattered light and the error in the intensity of the transmitted light can be canceled. When the reference turbidity is 0 to 400FNU, the turbidity detection signal processing unit 13 can output the ratio of the intensity of scattered light to the intensity of transmitted light as the intensity signal s1 of scattered light or transmitted light. The turbidity detection signal processing unit 13 may output the intensity of the scattered light and the intensity of the transmitted light, and the control calculation unit 30 may calculate the ratio of the intensity of the scattered light to the intensity of the transmitted light.

Next, measurement of fluorescence intensity of the sample water 3 will be described. The optical system 20 for fluorescence detection includes a light emitting portion 21 for fluorescence detection and a light receiving portion 22 for fluorescence detection. The fluorescence detection light-emitting unit 21 irradiates excitation light L3. The fluorescence detection light-emitting unit 21 irradiates the sample water 3 in the flow cell 2-2 with excitation light L3. For example, the excitation light L3 is ultraviolet light. The fluorescence detection light emitting unit 21 may include an ultraviolet light source therein. As an example, the ultraviolet light source is a Xenon flash lamp (Xenon flash lamp). The ultraviolet light source may be an LED or a laser irradiation device.

The fluorescence detection light-emitting unit 21 may include an optical filter therein. Since the optical filter is included, the fluorescence detection light emitting section 21 can irradiate the flow cell 2-2 with light of a predetermined wavelength range of the excitation light L3. In this example, the measurement target substance is PAH. PAH emits fluorescence most efficiently around 250nm in the wavelength of excitation light. Therefore, as an example, the transmission wavelength of the optical filter inside the fluorescence detection light-emitting section 21 is set to be 200nm to 300 nm.

The excitation light L3 is irradiated to the sample water 3 inside the flow cell 2-2, thereby generating fluorescence L4. The fluorescence detection light receiving unit 22 receives the fluorescence L4. The fluorescence detection light receiving unit 22 converts the fluorescence L4 into a fluorescence intensity signal. As an example, the fluorescence detection light receiving unit 22 is a photodiode.

The fluorescence detection light receiving unit 22 may include an optical filter therein. Since the optical filter is included, the fluorescence detection light receiving unit 22 can receive light of a predetermined wavelength range of the fluorescence L4. In this example, the measurement target substance is PAH. When the wavelength of excitation light of PAH is around 250nm, the fluorescence wavelength is around 350 nm. Therefore, as an example, the transmission wavelength of the optical filter inside the fluorescence detection light receiving portion 22 is set to 300nm to 400 nm.

The fluorescence detection signal processing unit 23 processes the fluorescence intensity signal from the fluorescence detection light receiving unit 22. The fluorescence detection signal processing unit 23 can amplify the signal from the fluorescence detection light receiving unit 22. The fluorescence detection signal processing section 23 can remove noise from the signal from the fluorescence detection light receiving section 22. The fluorescence detection signal processing unit 23 processes the fluorescence intensity signal from the fluorescence detection light receiving unit 22, and outputs the processed fluorescence intensity signal as a fluorescence intensity signal s2.

The fluorescence intensity correcting unit 34 corrects the fluorescence intensity. The fluorescence intensity correcting unit 34 corrects the fluorescence intensity signal s2 from the fluorescence detection signal processing unit 23 based on the turbidity D1 of the sample water 3. For example, since the fluorescence intensity is smaller as the turbidity D1 of the sample water 3 is higher, the fluorescence intensity signal s2 is multiplied by the correction coefficient to calculate the fluorescence intensity signal s3, and the correction coefficient is larger as the turbidity D1 of the sample water 3 is higher (see fig. 12). The correction coefficient is preferably acquired in advance.

The density calculating unit 35 calculates the density C1. The concentration calculating unit 35 calculates the concentration C1 based on the fluorescence intensity signal s 3. In this example, the concentration calculating unit 35 calculates the concentration C1 based on the fluorescence intensity signal s3 corrected by the fluorescence intensity correcting unit 34. The concentration calculating unit 35 may calculate the concentration C1 by multiplying the fluorescence intensity signal s3 by a concentration correction coefficient calculated by concentration correction. The density calculating unit 35 may output the density C1 to an external device or the like.

The water quality analysis device 100 performs a calibration operation using the calibration aqueous solution. In this example, the correction operation refers to turbidity correction and density correction. The correction aqueous solution is an aqueous solution used for the correction operation. The correction aqueous solution can flow inside the flow path 1 and the flow cell 2. The aqueous correction solution used in the turbidity correction and the aqueous correction solution used in the concentration correction may be different from each other. The aqueous correction solution may be any one of a turbidity standard sample for turbidity correction and a fluorescence intensity standard sample for concentration correction.

Turbidity correction will be described. In the present specification, in order to calculate the turbidity D1 of the sample water 3, the turbidity calculating unit 33 sets the turbidity correction coefficient b1. The turbidity correction coefficient b1 converts the intensity signal s1 of scattered light or transmitted light from the sample water 3 into the turbidity D1 of the sample water 3. The following expression 1 holds for the turbidity correction coefficient b1. In equation 1, the offset (off set) is set to e1. The offset e1 may be a constant. Offset e1 may also be 0. The turbidity correction coefficient b1 may be a constant coefficient. The turbidity correction coefficient b1 may be a variable. The turbidity correction coefficient b1 may be a variable that varies according to the intensity signal s1. In the case where the turbidity correction coefficient b1 is a variable, correction is performed using a plurality of turbidity standard samples having different turbidity. In addition, instead of the turbidity correction coefficient b1, the turbidity calculation unit 33 may set a function f that establishes the turbidity d1=f (intensity signal s 1) of the sample water 3. In this case too, calibration was carried out with turbidity standard samples having different turbidity.

(mathematics 1)

D1＝b1×s1+e1

In the turbidity correction, a turbidity standard sample was used. The turbidity standard sample is a sample serving as a reference for turbidity measurement, and is an example of a calibration aqueous solution. Turbidity standard the turbidity of a turbidity standard is known. Therefore, in the turbidity correction, by measuring the intensity signal of the turbidity standard sample, the turbidity correction coefficient b1 can be calculated by the equation 1. Turbidity standard samples are usually Fulmahydrazine (Formazin), kaolin, polystyrene. The Fulmahydrazine is a mixed aqueous solution prepared by polymerizing hydrazine sulfate and hexamethylenetetramine. Kaolin is an aqueous solution prepared by refining particles of kaolinite. Polystyrene is a suspension of polystyrene-based particles.

Concentration correction will be described. In the present specification, the density calculating unit 35 sets the density correction coefficient b2 in order to calculate the density C1. The concentration correction coefficient b2 converts the fluorescence intensity of the measurement target substance into the concentration C1 of the measurement target substance. The following equation 2 holds for the density correction coefficient b2. In equation 2, the offset is set to e2. The offset e2 may be a constant. Offset e2 may also be 0. The density correction coefficient b2 may be a constant coefficient. The density correction coefficient b2 may be a variable. The concentration correction coefficient b2 may be a variable that varies according to the fluorescence intensity signal s 3. In the case where the concentration correction coefficient b2 is a variable, correction is performed using a plurality of fluorescent intensity standard sample concentrations having different concentrations. The concentration calculation unit 35 may set a function g for setting the concentration c1=g (fluorescence intensity signal s 3) instead of the concentration correction coefficient b2. In this case too, correction was performed using fluorescent intensity standard sample concentrations having a plurality of different concentrations.

(mathematics 2)

C1＝b2×s3+e2

In the correction of fluorescence intensity (concentration correction), a fluorescence intensity standard sample is used. The fluorescence intensity standard sample is a sample serving as a reference for concentration measurement, and is an example of a calibration aqueous solution. The concentration of the fluorescent intensity standard sample is known. Therefore, in the correction of the fluorescence intensity, by measuring the fluorescence intensity of the fluorescence intensity standard sample, the concentration correction coefficient b2 can be calculated by the equation 2. When the turbidity of the fluorescent intensity standard sample is known, the fluorescent intensity may be corrected by the turbidity of the standard sample, and the concentration correction coefficient b2 may be calculated. The fluorescent intensity standard sample differs for each substance to be measured. In this example, since the substance to be measured is PAH, a sample containing phenanthrene or amine is used as an example of the fluorescence intensity standard sample. The fluorescent intensity standard sample may be PAH.

In the water quality analysis device 100 in which the turbidity correction coefficient b1 is not set, turbidity correction is performed before concentration measurement. In the water quality analysis device 100 in which the concentration correction coefficient b2 is not set, concentration correction is performed before concentration measurement. In addition, the turbidity correction coefficient b1 and the concentration correction coefficient b2 may change due to contamination inside the flow cell 2 through which the sample water 3 flows and/or aged deterioration of optical components. In order to correct the influence of contamination inside the flow cell 2 through which the sample water 3 flows and/or aged deterioration of the optical components, it is preferable to update the turbidity correction coefficient b1 and the concentration correction coefficient b2 periodically.

Fig. 2 is a diagram showing the flow path 1 of the aqueous humor analysis device 100 in detail. The water quality analysis device 100 includes a first switching unit 40 in the flow path 1. In fig. 2, orthogonal coordinate axes of the X axis, the Y axis, and the Z axis are shown. The flow cell 2 extends in the Z-axis direction (height direction). The flow cell 2 extends in a direction perpendicular to the XY plane.

The water quality analyzer 100 of the present example has both a fluorescence measurement function and a turbidity measurement function. Accordingly, the turbidity correction and the fluorescence intensity correction (concentration correction) are performed in the water quality analysis device 100, respectively. At this time, it is necessary to prepare an amount of the aqueous calibration solution to be circulated through all the channels 1 in the water quality analyzer 100. Therefore, in the case of performing calibration on a ship or the like, it is necessary to secure a volume for storing a large amount of the calibration aqueous solution in addition to the water quality analyzer.

In this example, the first switching section 40 switches whether to supply the sample water 3 or the correction aqueous solution to the flow cell 2-1 (and the flow cell 2-2). That is, the first switching section 40 switches the flow path 1 upstream of the flow cell 2. Therefore, since the water quality analysis device 100 includes the first switching unit 40, the flow path 1 for the sample water 3 and the flow path 1 for the calibration aqueous solution can be easily switched. Therefore, the amount of the correction aqueous solution to be used can be suppressed.

The first switching section 40 is disposed upstream with respect to the flow cell 2 in the flow path 1 through which the sample water 3 and the correction aqueous solution flow. In this example, the first switching section 40 is disposed upstream with respect to the flow cell 2-1 and the flow cell 2-2. By providing the first switching portion 40 upstream with respect to the flow cell 2-1 and the flow cell 2-2, turbidity correction and concentration correction can be easily performed.

In this example, the first switching portion 40 is a three-way valve. The first switching portion 40 has a regulator valve 42 and a regulator valve 44. The control valve 42 opens and closes the flow path 1 for the sample water 3. The control valve 44 opens and closes the flow path 1 for the aqueous correction solution. In fig. 2, the regulator valve 42 and the regulator valve 44 are opened. In the figure, the control valve 42 and the control valve 44 are indicated as white in the case where they are open, and the control valve 42 and the control valve 44 are indicated as black in the case where they are closed.

In this example, the directions in which the sample water 3 and the correction aqueous solution flow in the flow path 1 are directions from the-Z axis toward the +z axis. That is, the directions in which the sample water 3 and the correction aqueous solution flow are directions from the negative side in the height direction toward the positive side in the height direction. Since the directions in which the sample water 3 and the correction aqueous solution flow are directions from the negative side in the height direction toward the positive side in the height direction, it is preferable that the sample water 3 and the correction aqueous solution flow under pressure. The first switching part 40 may be disposed under the flow cell 2 in the height direction.

Fig. 3 is a diagram showing the first switching unit 40 when turbidity or concentration of the sample water 3 is measured in the water quality analysis device 100. When the turbidity or concentration of the sample water 3 is measured, the regulating valve 42 is opened and the regulating valve 44 is closed. Thus, the sample water 3 flows toward the flow cell 2.

The sample water 3 is supplied from the deaeration tank 90. The deaeration tank 90 can remove bubbles of the sample water 3. The deaeration tank 90 may be an open atmosphere type. The deaeration tank 90 may be pressurized. The deaeration tank 90 may be of a swirl type. The deaeration tank 90 may remove bubbles of the sample water 3 by a known method.

In this example, in the flow path 1 through which the sample water 3 flows, the first switching section 40 is provided between the flow cell 2 and the deaeration tank 90. In fig. 3, in the flow path 1 through which the sample water 3 flows, the first switching section 40 is provided between the flow cell 2-1 and the deaeration tank 90. In the flow path 1 through which the sample water 3 flows, the first switching unit 40 is provided between the flow cell 2 and the deaeration tank 90, whereby the calibration operation can be performed without flowing the calibration aqueous solution through the deaeration tank 90. Therefore, the amount of the correction aqueous solution to be used can be suppressed.

Fig. 4 is a diagram showing the first switching unit 40 when turbidity correction or concentration correction is performed in the water quality analysis device 100. At the time of turbidity correction or concentration correction, the regulating valve 42 is closed and the regulating valve 44 is opened. Therefore, the correction aqueous solution 4 is supplied to the flow cell 2.

The correction aqueous solution 4 is supplied from the syringe 70. The syringe 70 may supply the correction aqueous solution 4 to the flow cell 2 at the start of the correction operation. The syringe 70 may function as a correction aqueous solution supply unit. At the end of the calibration operation, the syringe 70 may remove the calibration aqueous solution 4 from the flow cell 2. The syringe 70 is an example of the correction aqueous solution removing portion. The syringe 70 may be actuated by means of a device and/or a machine, or may be actuated manually. In addition, a device functioning as a correction aqueous solution supply unit and a correction aqueous solution removal unit may be provided instead of the syringe 70. The water quality analyzer 100 can supply the correction aqueous solution 4 by using the syringe 70 or the like by providing the first switching unit 40, and can suppress the amount of the correction aqueous solution 4 to be used.

In this example, the correction aqueous solution 4 may not flow through the flow path 1 while being supplied to the flow cell 2. That is, the correction aqueous solution 4 may be stationary at a certain height of the flow path 1. By continuously pressing the syringe 70, the aqueous correction solution 4 can be made stationary. In the case of turbidity correction, the aqueous correction solution 4 (turbidity standard sample) can be stationary in such a manner as to fill the flow cell 2-1. In the case of concentration correction, the aqueous correction solution 4 (fluorescence intensity standard sample) may be stationary in such a manner as to fill the flow cell 2-2. In the correction operation, the correction aqueous solution does not flow through the flow path 1, and therefore the amount of the correction aqueous solution 4 used can be suppressed.

Fig. 5 is a diagram showing a water quality analysis device 200 according to another embodiment. In fig. 5, the flow path 1 of the aqueous humor analysis device 200 is shown in detail. The water quality analysis device 200 of fig. 5 is different from the water quality analysis device 100 of fig. 2 in that the water quality analysis device 200 of fig. 5 includes the second switching unit 50 in the flow path 1. Other structures of the water quality analyzer 200 of fig. 5 may be the same as those of the water quality analyzer 100 of fig. 2.

In this example, the second switching section 50 switches whether to circulate the sample water 3 or the correction aqueous solution 4 or to discharge the sample water 3 or the correction aqueous solution 4. That is, the second switching unit 50 switches the flow path 1 downstream of the flow cell 2. Therefore, since the water quality analysis device 200 is provided with the second switching unit 50, the circulation and discharge of the sample water 3 and the calibration aqueous solution 4 can be easily switched.

The second switching unit 50 is disposed downstream of the flow cell 2 in the flow path 1 through which the sample water 3 and the correction aqueous solution 4 flow. In this example, the second switching section 50 is disposed downstream with respect to the flow cell 2-1 and the flow cell 2-2.

In this example, the second switching portion 50 is a three-way valve. The second switching portion 50 has a regulator valve 52 and a regulator valve 54. The control valve 52 opens and closes the discharge flow path 1. The control valve 54 opens and closes the circulation flow path 1. In fig. 5, the regulator valve 52 and the regulator valve 54 are opened. In the figure, the control valve 52 and the control valve 54 are indicated as white when they are open, and the control valve 52 and the control valve 54 are indicated as black when they are closed.

Fig. 6 is a diagram showing the first switching unit 40 and the second switching unit 50 when turbidity or concentration of the sample water 3 is measured in the water quality analysis device 200. When the turbidity or concentration of the sample water 3 is measured, the control valves 42 and 52 are opened, and the control valves 44 and 54 are closed. Thus, the sample water 3 flows toward the flow cell 2.

In this example, the control valve 52 is opened to drain the sample water 3. In the measurement of the fluorescence intensity of the sample water 3, the sample water 3 is easily degraded because the excitation light L3 is irradiated to the sample water 3. Thus, the sample water 3 is preferably discharged rather than circulated.

Fig. 7 is a diagram showing the first switching unit 40 and the second switching unit 50 when the water quality analyzer 200 performs the concentration correction. At the time of the concentration correction, the control valves 44 and 52 are opened, and the control valves 42 and 54 are closed. The correction aqueous solution 4 flows into the flow cell 2. In this example, the aqueous correction solution 4 is a fluorescent intensity standard sample. The water quality analysis device 200 may be provided with the device 80 at the time of the density correction. The device 80 may also be an external device.

In this example, the adjusting valve 52 is opened to discharge the aqueous correction solution 4. That is, in the case where the aqueous correction solution 4 is a fluorescent intensity standard sample, the second switching section 50 discharges the aqueous correction solution 4. In the concentration correction, since the excitation light L3 is irradiated to the sample water 3, the correction aqueous solution 4 is easily degraded. Therefore, the correction aqueous solution 4 is preferably discharged instead of circulated. When the aqueous calibration solution 4 is a fluorescent intensity standard sample, the calibration operation can be performed with high accuracy by discharging the aqueous calibration solution 4.

The device 80 may supply the correction aqueous solution 4 to the adjustment valve 44 of the first switching portion 40. In this example, the supply device 80 continuously supplies the correction aqueous solution 4. Therefore, unlike fig. 4, in the correction operation, the correction aqueous solution 4 flows into the flow cell 2.

Fig. 8 is a diagram showing the first switching unit 40 and the second switching unit 50 when turbidity correction is performed in the water quality analysis device 200. At the time of turbidity correction, the control valves 44 and 54 are opened, and the control valves 42 and 52 are closed. The correction aqueous solution 4 flows into the flow cell 2. In this example, the aqueous calibration solution 4 is a turbidity standard. The water quality analysis device 200 may be provided with the device 80 at the time of turbidity correction. The device 80 may also be an external device.

In this example, the adjusting valve 54 is opened to circulate the aqueous correction solution 4. That is, in the case where the aqueous correction solution 4 is a turbidity standard sample, the second switching unit 50 circulates the aqueous correction solution 4. The correction aqueous solution 4 having passed through the regulating valve 54 of the second switching portion 50 can be returned to the regulating valve 44 of the first switching portion 40. In the turbidity correction, the turbidity standard sample is not easily deteriorated. Therefore, in order to suppress the amount of the aqueous correction solution 4 to be used, it is preferable to circulate the aqueous correction solution 4.

In the case of circulating the aqueous correction solution 4, the current correction result may be corrected based on the past execution history of the correction operation. For example, the current correction result is corrected based on the irradiation history of the infrared light L1 or the excitation light L3. The irradiation history of the infrared light L1 or the excitation light L3 refers to the irradiation time and irradiation intensity of the infrared light L1 or the excitation light L3. If the irradiation time of the infrared light L1 or the excitation light L3 is long, the deterioration of the correction aqueous solution 4 advances. In addition, if the irradiation intensity of the infrared light L1 or the excitation light L3 is large, the deterioration of the correction aqueous solution 4 advances. By correcting the current correction result based on the past execution history of the correction job, the influence of the deterioration of the correction aqueous solution 4 can be reduced, and the correction job can be executed more accurately. It is preferable to acquire in advance a relation between the irradiation history of the infrared light L1 or the excitation light L3 and the manner of correcting the deterioration of the aqueous solution 4.

The device 80 may supply the correction aqueous solution 4 to the adjustment valve 44 of the first switching portion 40. The correction aqueous solution 4 having passed through the regulating valve 54 of the second switching portion 50 can be returned to the device 80. The device 80 can supply the correction aqueous solution 4 again to the regulating valve 44 of the first switching portion 40. In this example, the device 80 circulates the aqueous correction solution 4 continuously. Therefore, unlike fig. 4, in the correction operation, the correction aqueous solution 4 flows into the flow cell 2.

Fig. 9 is a diagram showing a water quality analysis device 300 according to another embodiment. In fig. 9, the flow path 1 of the water quality analysis device 300 is shown in detail. The water quality analysis device 300 of fig. 9 differs from the water quality analysis device 100 of fig. 2 in that the water quality analysis device 300 of fig. 9 includes the third switching unit 60 in the flow path 1. Other structures of the water quality analysis device 300 of fig. 9 may be the same as those of the water quality analysis device 100 of fig. 2.

In this example, the third switching unit 60 switches whether to supply the sample water 3 or the correction aqueous solution 4 to the flow cell 2-2. That is, the third switching unit 60 switches the flow path 1 between the flow cell 2-1 and the flow cell 2-2. Therefore, since the water quality analysis device 100 includes the third switching unit 60, the flow path 1 for the sample water 3 and the flow path 1 for the calibration aqueous solution can be easily switched between the flow cell 2-1 and the flow cell 2-2. When only the flow cell 2-2 is corrected (concentration correction), the amount of the aqueous correction solution 4 used can be suppressed.

The third switching unit 60 is disposed downstream of the flow cell 2-1 in the flow path 1 through which the sample water 3 and the correction aqueous solution 4 flow. The third switching unit 60 is disposed upstream of the flow cell 2-2 in the flow path 1 through which the sample water 3 and the correction aqueous solution 4 flow. The third switching section 60 is provided between the two flow cells 2 in the flow path 1 through which the sample water 3 and the correction aqueous solution 4 flow.

In this example, the third switching unit 60 is a three-way valve. The third switching portion 60 has a regulator valve 62 and a regulator valve 64. The control valve 62 opens and closes the flow path 1 for the sample water 3. The control valve 64 opens and closes the flow path 1 for the aqueous correction solution.

Fig. 10 is a diagram showing a water quality analysis device 400 of a comparative example. Fig. 10 shows in detail the flow path 1 of the water quality analyzer 400 when turbidity or concentration of the sample water 3 is measured. The water quality analyzer 400 of fig. 10 differs from the water quality analyzer 100 of fig. 3 in that the water quality analyzer 400 of fig. 10 does not include the first switching unit 40. Other structures of the water quality analysis device 400 of fig. 10 may be the same as those of the water quality analysis device 100 of fig. 3.

Fig. 11 is a diagram showing a comparison between the water quality analyzer 100 of the example and the water quality analyzer 400 of the comparative example. In estimating the amount of the correction aqueous solution to be used, the channel diameter of the channel 1 is set toThe total flow path length of the apparatus of the water quality analyzer was 400cm, the optical system flow path length was 40cm, and the deaeration tank capacity of the deaeration tank 90 was 2000mL. The optical system flow path length is a flow path length of a flow path provided in an optical system of the water quality analysis device. The optical system channel length is a channel length from the channel 1 provided in the turbidity detection optical system 10 to the channel 1 provided in the fluorescence detection optical system 20.

In the water quality analyzer 400, the correction operation is performed in a state where the total flow path and the deaeration tank 90 in the water quality analyzer 400 are filled with the correction aqueous solution 4. Therefore, the amount of the correction aqueous solution used for the correction work becomes large, and the amount of the correction aqueous solution becomes 2201ml.

On the other hand, since the water quality analyzer 100 includes the first switching unit 40, the flow path 1 from the deaeration tank 90 is shut off by the first switching unit 40. Therefore, the correction operation can be performed in a state where only the flow path 1 provided in the vicinity of the optical system is filled with the correction aqueous solution 4. In this case, since the correction aqueous solution 4 is not filled in the total device flow path and the deaeration tank 90 of the water quality analysis device 100 excluding the optical system flow path, the correction aqueous solution amount can be reduced to 20.1ml. The amount of the calibration aqueous solution in the water quality analysis device 100 during the calibration operation may be 100ml or less. The amount of the aqueous calibration solution in the water quality analyzer 100 is less than 1% as compared to the amount of the aqueous calibration solution in the water quality analyzer 400. Therefore, the volume for storing the correction aqueous solution 4 can be reduced, and the correction operation can be easily performed.

Fig. 12 is a diagram showing an example of the relationship between turbidity and fluorescence intensity. In fig. 12, a solid line indicates an ideal value, and a broken line indicates a measured value.

As shown in fig. 12, the difference between the ideal value of the fluorescence intensity and the measured value becomes large if the turbidity becomes high due to the internal filter effect. Therefore, the fluorescence intensity correcting unit 34 preferably corrects the fluorescence intensity so that the fluorescence intensity approaches an ideal value. In the example of fig. 12, the fluorescence intensity correction unit 34 multiplies the fluorescence intensity by a correction coefficient to correct the fluorescence intensity, and the correction coefficient increases as the turbidity increases. As an example, the correction coefficient is represented by an ideal value of fluorescence intensity/a measured value of fluorescence intensity.

The present invention has been described above using the embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments. It is apparent to those skilled in the art that various changes and modifications can be made to the above embodiments. As is clear from the description of the claims, the embodiments to which such changes and modifications are applied can be included in the technical scope of the present invention.

It should be noted that the operations, sequences, steps, and execution sequences of the processes in the apparatuses, systems, programs, and methods shown in the claims, the description, and the drawings may be implemented in any order unless specifically indicated as "prior", "earlier", or the like, and the output of the preceding process is not used in the following process. The operation flows in the claims, specification, and drawings do not necessarily require the order to be performed, even though the description has been made using "first", "next", etc. for convenience.

Claims (9)

1. A water quality analyzer, characterized in that a calibration operation is performed using a calibration aqueous solution, the concentration of a substance to be measured in sample water is measured,

the water quality analysis device is provided with:

a flow cell for flowing the sample water and the correction aqueous solution; and

a first switching section that switches whether to supply the sample water or the correction aqueous solution to the flow cell.

2. The water quality analysis device according to claim 1, wherein,

the first switching part is a three-way valve.

3. A water quality analysis device according to claim 1 or 2, wherein,

the water quality analysis device further comprises a deaeration tank for removing bubbles of the sample water and supplying the bubbles to the flow cell,

the first switching unit is located between the flow cell and the deaeration tank in a flow path through which the sample water flows.

4. A water quality analysis device according to any one of claim 1 to 3, wherein,

the first switching portion is disposed below the flow cell in a height direction.

5. A water quality analysis device according to any one of claims 1 to 4,

the first switching section is disposed upstream with respect to the flow cell in a flow path through which the sample water and the correction aqueous solution flow.

6. A water quality analysis device according to any one of claims 1 to 5, wherein,

the water quality analysis device further includes a correction aqueous solution removal unit that removes the correction aqueous solution from the flow cell when the correction operation is completed.

7. The water quality analysis device according to claim 5, wherein,

the water quality analyzer further includes a second switching unit that is provided downstream of the flow cell in a flow path through which the sample water and the correction aqueous solution flow, and that switches between circulating and discharging the sample water or the correction aqueous solution.

8. The water quality analysis device according to claim 7, wherein,

the aqueous calibration solution is any one of a turbidity standard sample for turbidity calibration and a fluorescence intensity standard sample for concentration calibration,

in the case where the aqueous correction solution is the turbidity standard sample, the second switching section circulates the aqueous correction solution,

in the case where the correction aqueous solution is the fluorescence intensity standard sample, the second switching section discharges the correction aqueous solution.

9. A water quality analysis device according to any one of claims 1 to 5, wherein,

the water quality analysis device is provided with a plurality of flow cells,

the water quality analyzer further includes a third switching unit provided between the two flow cells in a flow path through which the sample water and the correction aqueous solution flow.