CN209961769U - Water quality analyzer and water quality on-line monitoring system - Google Patents

Abstract

The utility model provides a water quality analyzer, include: a reaction measurement unit; the liquid taking and delivering unit comprises at least one inlet and at least one outlet; the liquid taking and delivering unit further comprises a quantitative element, which comprises: a dosing fluid circuit having a fixed total circuit volume and configured to be in selective fluid communication with the at least one inlet and the at least one outlet of the tapping fluid unit, the water sample and/or reagent being able to flow into the dosing fluid circuit when the dosing fluid circuit is in fluid communication with the at least one inlet, and the tapping fluid unit being able to deliver a volume of the water sample and/or reagent corresponding to the fixed total circuit volume to the reaction measurement unit when the dosing fluid circuit is in fluid communication with the at least one outlet. With the help of the water quality analyzer, the liquid such as water sample, reagent and the like to be sent into the reaction measurement unit can be accurately quantified through low-cost physical quantification, and expensive injection pumps are not used for quantification. The utility model discloses still relate to a quality of water on-line monitoring system.

Description

Water quality analyzer and water quality on-line monitoring system

Technical Field

The utility model relates to a water quality analyzer, for example this water quality analyzer can be used for measuring, thereby the basic situation of online analysis play quality of water to the multiple material content in the water sample. The utility model discloses still relate to a quality of water on-line monitoring system including this kind of water quality analyzer.

Background

Currently, the problem of water pollution is attracting increasing attention as a prominent environmental protection problem. In order to protect the water environment in which people live and ensure the drinking water hygiene of people, on one hand, the water quality in production and life needs to be detected, and on the other hand, the monitoring on the discharge of various kinds of production and domestic sewage needs to be enhanced.

In the process of monitoring water environment, a water quality detection device is generally adopted, and the water quality detection device is widely applied to power plants, domestic sewage treatment plants, textile plants, pharmaceutical factories, environmental protection departments, epidemic prevention departments, hospitals and the like. In particular, the quality of the water quality analyzer plays an important role in monitoring the water environment.

In the prior art, it is known to use a water quality analyzer for detection and analysis, and such a water quality analyzer can perform online monitoring of the content of various substances such as silicon, phosphate and the like in water samples of various industries such as surface water, drainage of ditches, domestic sewage, industrial wastewater and the like by a colorimetric method. For this purpose, such water quality analyzers are provided with a reaction cell which can also be used as a measuring cell. The reaction tank is installed in a control module capable of flexibly setting temperature. The control module is provided with a set of high-precision optical measurement systems to realize accurate measurement of the contents of various substances such as silicon, phosphate and the like.

For example, in the existing online COD water quality monitor, the main flow path includes a liquid taking and delivering unit composed of a high-precision syringe pump, a multi-way selector valve and a buffer liquid storage mechanism. The liquid taking and feeding unit can realize the sequential sample feeding function of different reagents, standard liquid and samples and push the reagents, the standard liquid and the samples into the reaction measuring cell for chemical reaction.

However, in order to ensure the reliability of the water quality analysis result, the volumes of various liquids such as water samples, reagents, and standard solutions need to be accurately quantified. In the prior art, such precise dosing of liquid is accomplished by expensive syringe pumps, often resulting in a substantial increase in the cost of the overall water quality analyzer. In addition, since the syringe pump is a moving part, inevitable wear also causes a gradual reduction in the actual pumping accuracy, which is also a big drawback for a water quality analyzer with high accuracy requirements.

Thus, there is a continuing need in the art for improvements in water quality analyzers that avoid many of the problems described above, and it is desirable that water quality analyzers be less costly, while at the same time ensuring the accuracy of the water quality analysis.

SUMMERY OF THE UTILITY MODEL

The utility model provides a water quality analyzer, include: a reaction measuring unit configured to allow a water sample and a reagent to be mixed therein; a draw solution unit comprising at least one inlet and at least one outlet, wherein the sample of water and the reagent can flow into the draw solution unit via the at least one inlet, and the at least one outlet is in fluid communication with the reaction measurement unit to enable the sample of water and the reagent to be fed into the reaction measurement unit via the at least one outlet; wherein the liquid taking and delivering unit further comprises a quantitative element for quantifying the water sample and/or the reagent respectively, the quantitative element comprising: a dosing fluid line having a fixed total line volume and configured to be selectively fluidly connectable to the at least one inlet and the at least one outlet of the draw and feed unit, wherein when the dosing fluid line is in fluid communication with the at least one inlet, the sample of water and/or the reagent can flow into the dosing fluid line, and when the dosing fluid line is in fluid communication with the at least one outlet, the draw unit can feed the sample of water and/or the reagent into the reaction measurement unit in a volume corresponding to the fixed total line volume.

With the help of the water quality analyzer, the liquid such as water sample, reagent and the like to be sent into the reaction measurement unit can be accurately quantified through low-cost physical quantification, and expensive injection pumps are not used for quantification.

In a preferred embodiment, the liquid pick-and-send unit comprises a multi-way selector valve comprising the at least one inlet and the at least one outlet, the dosing fluid line being configured for direct fluid connection with the multi-way selector valve to be selectively in fluid communication with the at least one inlet and the at least one outlet. Therefore, the multi-way selector valve which is convenient to operate can be adopted to ensure the switching of the quantitative fluid pipeline, the inlet of each liquid and the reaction measuring unit.

In particular, the dosing element may further comprise an optical sensor arranged at a fixed position along the length of the dosing fluid conduit to enable optical dosing of the sample water and/or the reagent to a volume corresponding to the conduit volume of the dosing fluid conduit between the multi-way selector valve and the fixed position. Thus, flexibility in quantifying liquid can be provided by means of optical quantification to achieve accurate quantification of various volumes of liquid.

For example, the multi-way selector valve may include a common port selectively fluidly communicable with the at least one inlet and the at least one outlet, the dosing fluid line being connected at one end to the common port. By means of the common port, fluid communication and disconnection between the fixed-quantity fluid line and the respective inlet and outlet of the multi-way selector valve can be easily achieved.

Advantageously, the other end of the dosing fluid circuit is selectively in fluid communication with a first flow path on which a first pump is arranged or with a second flow path on which a second pump is arranged, the first pump being opposite to the second pump in pumping direction. The liquid pumping and pushing are realized through the two separated flow paths, so that the reliability and the control flexibility of the flow path system can be improved.

In some embodiments, the first pump may be an aspiration pump to draw the sample of water and/or the reagent into the dosing fluid line when it is in fluid communication with the dosing fluid line, and the second pump may be an air-blast pump to pump the dosed amount of the sample of water and/or the reagent out of the dosing fluid line when it is in fluid communication with the dosing fluid line. The liquid pump and the air blowing pump are not expensive injection pumps and only play a pumping role, so the cost is low.

Advantageously, the other end of the dosing fluid line may be connected with the first flow path and the second flow path, respectively, by means of a tee fitting. The three-way pipe joint is low in cost, but can also ensure that no liquid cross flow occurs between the first flow path and the second flow path.

Preferably, a fluid valve may be disposed on the second flow path between the tee joint and the second pump, the fluid valve being used to selectively connect or disconnect the second pump to the fixed-amount fluid line, thereby improving control flexibility and reliability of the flow path.

In particular, the port of the three-way union fluidly connected to the second flow path can be integrated into a body of the fluid valve. Because the port of the three-way fitting is integrated with the fluid valve, the otherwise long connecting line between the two now becomes an extremely short length. Therefore, the volume of the air column which can be sealed in the connecting pipeline during the quantitative determination is obviously reduced, and the precision of the physical quantitative determination is improved.

In addition, the first flow path can be selectively connected to a waste liquid unit to discharge waste liquid into the waste liquid unit through the quantitative fluid pipeline and the first flow path, so that the liquid in the reaction measurement unit is discharged/emptied.

The utility model discloses still relate to a quality of water on-line monitoring system, quality of water on-line monitoring system includes aforementioned water quality analyzer, water sample storage container, at least one reagent storage container and waste liquid storage container, wherein, water quality analyzer include with waste liquid storage container water sample storage container reagent storage container carries out fluid connection's interface. The water quality on-line monitoring system can accurately realize on-line monitoring or analysis of water quality.

Drawings

Fig. 1 schematically shows a schematic diagram of an online water quality monitoring system according to an embodiment of the present invention;

fig. 2 schematically shows a structure of an optical sensor in a water quality analyzer according to an embodiment of the present invention;

fig. 3A is a partial schematic view schematically illustrating a connection relationship between a fluid valve and a tee joint in a water quality analyzer according to an embodiment of the present invention;

fig. 3B schematically illustrates a structure of a fluid valve in a water quality analyzer according to an embodiment of the present invention;

fig. 4 schematically shows a schematic structural view of a water quality analyzer in its first working step according to an embodiment of the present invention;

fig. 5 schematically shows a schematic structural view of a water quality analyzer according to an embodiment of the present invention in its second working step;

fig. 6 schematically shows a schematic structural view of a water quality analyzer according to an embodiment of the present invention in a third working step thereof;

fig. 7 schematically shows a schematic structural view of a water quality analyzer in a fourth operation step thereof according to an embodiment of the present invention;

fig. 8 schematically shows a schematic structural view of a water quality analyzer according to an embodiment of the present invention in a fifth working step thereof; and

fig. 9 schematically shows a schematic structural diagram of a water quality analyzer in a sixth working step according to an embodiment of the present invention.

It should be noted that the drawings referred to are not all drawn to scale but may be exaggerated to illustrate various aspects of the present invention, and in this regard, the drawings should not be construed as limiting.

List of reference numerals:

10 a reaction measurement unit;

20 an optical sensor;

24 light emitting diodes;

26 a photodiode;

30 quantitative fluid lines;

a 50-way selector valve;

52 a common port;

60 a first flow path;

62 liquid pump;

70 a second flow path;

72 air-blowing pump;

74 fluid valve

80 a three-way pipe joint;

90 a waste liquid unit;

92 a waste liquid reservoir;

94 waste liquid valve;

96 recycling barrels;

100 water quality analyzer.

Detailed Description

First, in the drawings of the present invention, only the basic fluid connection relationship between the respective components of thewater quality analyzer 100 is schematically illustrated, and other necessary components (e.g., a control component, a power supply component, a driving component, etc.) in the fluid circuit are not specifically illustrated. However, it will be understood by those skilled in the art that the components not shown are not essential to the present invention and will not be described in detail below.

Secondly, the utility model discloses a water quality analyzer can be applied to under the multiple water quality measurement application occasion, for example to the measurement of indexes such as chemical oxygen demand, ammonia nitrogen content. In addition, it can also be understood that the water quality analyzer of the present invention can also be used in other systems of monitoring and analyzing equipment to measure other liquid components besides water quality.

Hereinafter, the first port of the fluid valve is denoted by COM, the second normally-open port of the fluid valve is denoted by NO, and the third normally-closed port of the fluid valve is denoted by NC.

Fig. 1 shows a schematic diagram of an online water quality monitoring system according to the present invention, including an exemplarywater quality analyzer 100. Specifically, in the system, thewater quality analyzer 100 may include various interfaces to the outside to connect with other devices that provide, for example, water samples, various reagents, air, standard solutions, detergents, waste solution treatment. In other words, a water sample, various reagents, air, a standard liquid, a cleaning agent (for example, three container bottles shown in the lower left side in fig. 1), and the like can be sent into thewater quality analyzer 100 via the water quality on-line monitoring system, and the waste liquid in thewater quality analyzer 100 can also be discharged to a waste liquid reservoir (for example, a waste liquid tank or a spare tank) located outside the system via an interface.

Awater quality analyzer 100 according to the present invention includes areaction measuring unit 10 configured to allow a water sample and a reagent (and optionally other liquids) to be mixed therein. Furthermore, thereaction measuring unit 10 may also involve at least one of chemically reacting, detecting, measuring, and analyzing the water sample and the reagent mixed therein. Thereaction measuring unit 10 can be installed in a control module in which temperature can be flexibly set, and is equipped with a dedicated or general-purpose measuring system to achieve accurate measurement and analysis of various substances, but these are not essential.

Thewater quality analyzer 100 according to the present invention further includes a liquid supply unit, which is a general term for each component that supplies, for example, a water sample, various reagents, air, a standard liquid, a detergent, etc. into thereaction measurement unit 10 or discharges a liquid such as a waste liquid from thereaction measurement unit 10 in the water quality analyzer.

To this end, the tapping unit may comprise at least one, preferably a plurality of inlets and at least one outlet. For example, liquids, such as water samples and/or reagents, located outside of thewater quality analyzer 100, e.g., in respective storage containers, can flow into the pick-and-feed unit via the aforementioned at least one inlet. And the aforementioned at least one outlet of the liquid taking and feeding unit should be in fluid communication with thereaction measuring unit 10 so as to be able to feed liquid such as water sample and/or reagent into thereaction measuring unit 10 of thewater quality analyzer 100 via the aforementioned at least one outlet. It is to be understood that the term "fluid communication" herein is not limited to direct fluid connection, but may also include indirect fluid communication of any intermediate conduit or component.

In a preferred embodiment, the aforementioned at least one inlet and the aforementioned at least one outlet of the tapping unit may be provided by amulti-way selector valve 50 comprised by the tapping unit. Themulti-way selector valve 50 may be, in particular, a multi-way rotary valve as is shown in the example of fig. 1. Advantageously, the water sample, various reagents, air, the standard solution, the cleaning agent, etc. may flow into themulti-way selector valve 50 via a plurality of inlets of themulti-way selector valve 50, respectively, and an outlet of themulti-way selector valve 50 may be in fluid communication with, for example, thereaction measurement unit 10 to which these water sample, various reagents, air are to be supplied, but may also be in fluid communication with other components in the liquid take and send unit, thereby indirectly supplying the water sample, various reagents, air, the standard solution, the cleaning agent, etc. to thereaction measurement unit 10 via these other components.

In a particularly advantageous embodiment, themulti-way selector valve 50 may include acommon port 52 at a central location thereof, whereby inlet and outlet ports in themulti-way selector valve 50 may be selectively fluidly connected via thecommon port 52. Therefore, thecommon port 52 can be used as an interface of themulti-way selector valve 50 with other components than thereaction measurement unit 10 and liquid sources such as a water sample, various reagents, air, a standard liquid, a detergent, and the like. It will be appreciated that themulti-way selector valve 50 may have more or fewer inlets and outlets than shown in FIG. 1.

In addition, in the present invention, the term "interface" may alternatively be understood as a "channel" or any suitable fluid flow space. Since there are advantageously multiple inlets and outlets to themulti-way selector valve 50, the complete independence and isolation between the extraction of the water sample and the various samples does not affect the results of the water quality monitoring. The controller itself for controlling the extraction sequence and the drainage sequence of the liquid extraction and delivery unit is not the key point of the present invention, and therefore is not described herein again.

In order to accurately quantify the amount of water sample, various reagents, standard solution, detergent, etc. flowing into thereaction measuring unit 10, the present invention is not implemented by an expensive syringe pump, but by means of a quantifying member described in detail below.

Particularly, thewater quality analyzer 100 according to the present invention may include a quantitative element for quantifying liquids such as water samples and reagents. The dosing element may for example comprise adosing fluid line 30, whichdosing fluid line 30 typically has a fixed total line volume. Generally, the total line volume is fixed as long as themetering fluid line 30 itself does not change significantly with time or temperature. Thus, in the case of themetering fluid line 30 itself, its cross-sectional area or arrangement may vary along its length, but this does not result in a change in the total line solvent. Preferably, at least a portion of thedosing fluid circuit 30 may be configured in the form of a coil (also referred to as a "buffer ring"), but thedosing fluid circuit 30 may also be implemented entirely from a straight tube.

In any case, thedosing fluid circuit 30 should be configured to be in selective fluid communication with at least one inlet and at least one outlet of a liquid pick-up unit, such as amulti-way selector valve 50. In particular, thedosing fluid line 30 is configured to be in direct fluid connection with themulti-way selector valve 50 to enable selective fluid communication with the at least one inlet and the at least one outlet. It is particularly preferred that thedosing fluid line 30 is directly connected to thecommon port 52 of themulti-way selector valve 50.

In the present invention, the aforementioned term "selective fluid communication" means that the communication between the two is selectively achievable, for example, by control of a controller. Typically, thedosing fluid line 30 will not be in direct simultaneous fluid communication with both the inlet and the outlet.

When thedosing fluid circuit 30 is in fluid communication with at least one inlet, a liquid sample, reagent, etc. can flow into thedosing fluid circuit 30 via the inlet (which is not typically the same inlet) to fill its circuit volume, e.g. to its full total volume. When themetering fluid line 30 is in fluid communication with at least one outlet, a fluid removal unit, such as amulti-way selector valve 50, can deliver at least one of a sample of water, a reagent, etc., to thereaction measurement unit 10 in a volume corresponding to the fixed total line volume of themetering fluid line 30. The premise for dosing liquids to a fixed total line volume is that these liquids should occupy the entire volume of thedosing fluid line 30. Therefore, this quantitative approach is also referred to as "physical quantitation". How to ensure that a liquid, such as a water sample, a reagent, etc., can occupy the entire volume of thedosing fluid circuit 30 will be explained further below.

Furthermore, the quantitative element of thewater quality analyzer 100 according to the present invention may further include anoptical sensor 20. In a preferred embodiment, theoptical sensor 20 may be disposed at a fixed location along the length of the dosing fluid circuit 30 (as shown in FIG. 1).

In one example, theoptical sensor 20 may be comprised of alight emitting diode 24 and a lightsensitive diode 26, see fig. 2. Theoptical sensor 20 detects the presence and absence of liquid in the conduit by the fact that thephotodiode 26 receives light from the led at different intensities, which results in thephotodiode 26 generating electrical signals of different intensities. For example, in the case of a fluid in the conduit,photodiode 26 will generate an electrical signal of about 0.04V, and in the case of a fluid in the conduit,photodiode 26 will generate an electrical signal of about 1.8V. Thus, as the liquid (or more precisely, the interface front between the liquid and the gas) in the conduit passes through the led 24 of theoptical sensor 20, the electrical signal generated by the conduit also varies greatly (e.g., by two orders of magnitude).

In the present invention, the accuracy of theoptical sensor 20 can also be improved based on the refraction principle (instead of directly receiving the light emitted from the light emitting diode), thereby avoiding making a wrong judgment due to a bubble or the like that may exist in the liquid (for example, a sudden rise of the signal of the photodiode due to the bubble).

Thus, the controller ofwater quality analyzer 100 in communication withoptical sensor 20 can ascertain that the liquid is in the line (e.g., dosing fluid line 30) to the fixed location whereoptical sensor 20 is located. In other words, with theoptical sensor 20, a liquid such as a water sample or a reagent can be optically metered to a volume corresponding to the line volume of themetering fluid line 30 between themulti-way selector valve 50 and the fixed position of theoptical sensor 20, since the liquid fills the line volume to the fixed position. To provide more flexible dosing, multipleoptical sensors 20 may be provided inwater quality analyzer 100, for example, at different locations spaced apart from each other along the length ofdosing fluid line 30 to enable multiple dosing volume values. In the present invention, this quantitative method is also called "optical quantification", and the corresponding volume of the liquid can be determined without occupying the whole volume of thequantitative fluid pipeline 30 with the liquid such as water sample and reagent.

In thewater quality analyzer 100, theoptical sensor 20 can be used not only for quantifying the liquid but also for diagnosing an abnormality of a different component in the entire flow path. As mentioned above, the electrical signal of theoptical sensor 20 can be well differentiated (e.g., spanning two orders of magnitude) in the presence or absence of liquid, so that the presence or absence of liquid in the fluid pipeline can be reliably detected by using theoptical sensor 20, which helps to determine whether the components in the entire flow path are in a normal operating state. For example, in a certain working step controlled by the controller, if the section of the flow path has a reverse detection result when there should be liquid or there should be no liquid, it can be determined that there is an abnormality and further inspection or repair is required.

It will be appreciated that with the dosing element of the present invention, accurate dosing of liquids such as water samples, reagents, etc. of different volumes is achieved by physical dosing of the total length of the dosing fluid line 30 (i.e. the "buffer ring") and/or optical dosing of theoptical sensor 20. And meanwhile, expensive injection pumps and the like are avoided, so that the cost of the whole system is reduced. In particular, in thewater quality analyzer 100, the pump is not used for dosing, but only for providing power (the operation of the pump will be described in detail below), which reduces the requirements on the pump, thereby reducing costs and significantly reducing the frequency of pump damage.

The other end of themetering fluid line 30, opposite the end connected to themulti-way selector valve 50, is selectively in fluid communication with either the first flow path 60 (located further down in FIG. 1) or the second flow path 70 (located further up in FIG. 1), as shown in FIG. 1. A first pump is disposed in thefirst flow path 60, and a second pump is disposed in thesecond flow path 70. The first and second pumps are opposite in pumping direction to the need to pump a metered volume of liquid.

For example, the first pump on the first flow path 60 (i.e., the imbibition flow path) can be an infusion pump 62 (e.g., a peristaltic pump), i.e., pumping away from thedosing fluid line 30, and the second pump on the second flow path 70 (i.e., the push flow path) can be an air-blast pump 72 (e.g., a peristaltic pump), i.e., pumping in a direction toward thedosing fluid line 30.

When thefirst flow path 60, in which thedraw pump 62 is located, is in fluid communication with thedosing fluid circuit 30, thedraw pump 62 may draw a liquid, such as a sample of water, a reagent, etc. (e.g., from the multi-way selector valve 50) into thedosing fluid circuit 30. When thesecond flow path 70 where the air-blowingpump 72 is located is in fluid communication with thequantitative fluid conduit 30, a physically and/or optically quantified liquid such as a water sample, reagent, etc. may be pumped out of the quantitative fluid conduit 30 (e.g., into the reaction measurement unit 10).

As previously mentioned, neither the first pump nor the second pump need to be an expensive syringe pump, as long as the pumping function is achieved. In addition, both the first and second pumps may preferably be driven by stepper motors to enable precise operation of the pumps to pump various liquids to any selected location in the fluid line.

In addition, thefirst flow path 60 can be selectively connected to thewaste liquid unit 90 to discharge waste liquid to thewaste liquid unit 90 via thequantitative fluid line 30 and thefirst flow path 60.

In order to switch between the fluid communication of thequantitative fluid conduit 30 with thefirst flow path 60 and the fluid communication with thesecond flow path 70, a fluid switching means is preferably provided at the other end of thequantitative fluid conduit 30. The fluid switching component is, for example, a three-way fitting 80 (e.g., a T-fitting) and may also be, for example, a three-way valve.

In an advantageous embodiment, afluid valve 74 may be disposed on thesecond flow path 70 between the fluid switching component (e.g., T-joint) and the second pump (i.e., downstream of the T-joint), and thefluid valve 74 may be used to selectively connect or disconnect the second pump from thedosing fluid line 30.

As shown in fig. 1, thefluid valve 74 may for example comprise three ports, namely a first port COM in constant communication with the second pump, a second normally open port NO for disconnecting the fluid communication between the second pump and thedosing fluid line 30, and a third normally closed port NC for bringing the second pump into fluid communication with thedosing fluid line 30. The switching on and off of these three ports of thefluid valve 74 in each step will be explained further below.

In a particularly preferred embodiment, the tee of tee fitting 80 (e.g., a T-fitting) involves one pass ofdosing fluid line 30, one pass offirst flow path 60, and one pass ofsecond flow path 70. While the port of the tee fitting 80 fluidly connected to thesecond flow path 70 is preferably integrated into the body of thefluid valve 74, as schematically illustrated in fig. 3A and 3B. Because this port of tee fitting 80 is integral withfluid valve 74, the otherwise longer connecting line between the two now becomes an extremely short (e.g., within 5 millimeters) length (e.g., see circled portion in FIG. 3B). Therefore, the volume of the air column which can be sealed in the connecting pipeline during the quantitative determination is obviously reduced, and the precision of the physical quantitative determination is improved. It is particularly preferred that this port of the tee fitting 80 may be used directly as the third normally closed port NC of thefluid valve 74.

An exemplary work flow of thewater quality analyzer 100 according to the present invention is explained in detail below with the aid of fig. 4 to 9.

First, as shown in fig. 4, the first working step is to load a water sample or standard solution. At this time, the fixed-volume fluid line 30 is in fluid communication with thecommon port 52 of themulti-way selector valve 50, thecommon port 52 is in fluid communication with an inlet of the feed water sample or standard fluid into themulti-way selector valve 50, and the first port COM of thefluid valve 74 is connected to the second normally open port NO (i.e., thesecond flow path 70 is not in communication with the fixed-volume fluid line 30). Thedraw pump 62 on thefirst flow path 60 is operated to draw sample or standard fluid into thedosing fluid line 30 via themulti-way selector valve 50.

Preferably, in order to allow the sample or standard liquid to fully occupy thedosing fluid line 30, thedraw pump 62 is operated to allow the sample or standard liquid to pass slightly beyond a fluid switching component, such as a tee fitting 80, located on the end of thedosing fluid line 30. In other words, a very small portion of the sampled or standard liquid may pass into thefirst flow path 60 via the tee fitting 80, but the volume of this portion should be kept very small. Since this port of the three-way joint 80, which is connected to thesecond flow path 70, is connected to the third normally-closed port NC of the fluid valve 74 (or directly to the third normally-closed port NC), it is ensured that liquid is not pumped to thesecond flow path 70.

Next, as shown in fig. 5, the second working step is to push the water sample or the standard solution into the reaction measuring cell. At this time, thesecond flow path 70 is caused to communicate with the fixed-amount fluid line 30 by switching from the second normally-open port NO to the third normally-closed port NC through thefluid valve 74. The air-blowingpump 72 is operated to send the water sample or the standard liquid in the fixedfluid line 30 in a volume corresponding to the fixed total line volume thereof to thereaction measurement unit 10 through the outlet of themulti-way selector valve 50.

Advantageously, due to the presence of the tee fitting 80, a very small portion of the sampled or standard fluid located on thefirst flow path 60 will not flow back into thedosing fluid line 30, thereby ensuring that no excess, unmeasured fluid will flow into thereaction measuring unit 10.

As shown in fig. 6, the third working step is the loading of the reagent. This operational step is similar to the first operational step, with the fixed-volume fluid line 30 being in fluid communication with thecommon port 52 of themulti-way selector valve 50, with thecommon port 52 being in fluid communication with the inlet for reagent into themulti-way selector valve 50, and with the first port COM of thefluid valve 74 being connected to the second, normally open port NO (i.e., thesecond flow path 70 being non-communicating with the fixed-volume fluid line 30). Thedraw pump 62 on thefirst flow path 60 is operated to draw sample or standard fluid into thedosing fluid line 30 via themulti-way selector valve 50.

However, unlike the first operation step, in the third operation step, the reagent is not necessarily pumped up to the entirequantitative fluid line 30, but is pumped up to the fixed position of theoptical sensor 20. This allows reagent to be metered to the volume between the fixed location of theoptical sensor 20 and the multi-way selector valve 50 (primarily common port 52).

Next, as shown in FIG. 7, the fourth work step is to push reagents into the reaction measurement cell. At this time, thesecond flow path 70 is caused to communicate with the fixed-amount fluid line 30 by switching from the second normally-open port NO to the third normally-closed port NC through thefluid valve 74. The air-blowingpump 72 is operated to feed a metered amount of reagent into the reaction-measuringcell 10 via the outlet of the multi-way selector valve 50 (which may not be the same outlet as in the second operating step).

At this time, the water sample and the reagent can be mixed in thereaction measuring unit 10. Subsequently, the third and fourth working steps may be repeatedly performed to load and push more of the same or other reagents according to the analysis requirements. It will be appreciated that the third and fourth steps may be performed a plurality of times when the volume of reagent required is an integer multiple of the volume of themetering fluid line 30 between the fixed position of theoptical sensor 20 and themulti-way selector valve 50. Alternatively, various reagents can also be fed into thereaction measuring cell 10 by a similar process.

It should be noted that the order of the first and second working steps and the third and fourth working steps can be interchanged, for example, the reagent can be added to thereaction measuring unit 10, and the water sample can be added. Alternatively, the steps of adding the reagent, adding the water sample, and then adding the same or different reagents can be adjusted according to actual needs. It will be understood, however, that the first/third working step must be performed before the corresponding second/fourth working step, i.e. the liquid occupying the fluid line is dosed first, and then the dosed liquid is fed to thereaction measuring unit 10, the sequence being irreversible.

As shown in fig. 8, the fifth operational step is the measurement analysis, i.e. the reaction-measuringcell 10 starts to operate. For example, digestion/chemical reactions may be performed within thereaction measurement unit 10. The digestion/chemical reaction requires waiting for a period of time to wait for the mixed liquid in the reaction cell to sufficiently digest/chemically react. For example, concentration measurement may also be performed in thereaction measurement unit 10. For example, at this time, the optical system of the measuring cell operates to measure the absorbance of the mixed liquid, and further calculate the concentration of the substance to be measured. But the operation of analyzing other water quality can be performed subsequently, and the details are not repeated herein.

After the fifth working step is completed, it is also conceivable to add the first to fourth working steps to perform multiple analyses or different types of precise analyses on the water sample.

As shown in fig. 9, the sixth working step is an evacuation operation. After the entire measurement or analysis is completed, thequantitative fluid line 30 is communicated with thefirst flow path 60, and thedrawing pump 62 is rotated to transfer the mixed liquid in thereaction measuring unit 10 to thewaste liquid unit 90 connected to thefirst flow path 60.

Thewaste unit 90 may include a waste reservoir 92 (e.g., a waste drum). As shown in fig. 9, thewaste unit 90 may also optionally include a waste valve 94 (e.g., a similar three-way fluid valve) for reliable flow path switching. For example, if clean cleaning liquid is being drained, the liquid is optionally drained into arecyclable bucket 96 of thewaste unit 90.

It is understood that in the sixth working step, the waste liquid may not be discharged out of thewater quality analyzer 100 through thequantitative fluid line 30, so as to avoid the influence of the waste liquid on the fluid line. For example, a discharge line may be separately provided instead of thedosing fluid line 30 and thefirst flow path 60 to discharge the waste liquid directly into a waste or recyclable bucket.

Further, operations such as blowing air to thereaction measuring unit 10 may be included in addition to the above-described exemplary steps, which are not listed here.

The above working steps can be repeated for a plurality of times to continuously realize the online monitoring of the water quality, the sequence of each working step can or cannot be exchanged according to the actual requirement, but the duration can be adjusted according to the specific requirement.

The specific embodiments described herein are merely illustrative of preferred embodiments and are not intended to limit the scope of the invention as defined by the claims that follow. Equivalent changes and modifications can be made by those skilled in the art according to the contents of the present invention, and these are all within the scope of the present invention.

Claims (11)

1. A water quality analyzer (100) comprising:

a reaction measurement unit (10) configured to allow a water sample and a reagent to be mixed therein;

a pipetting unit comprising at least one inlet via which the sample of water and the reagent can flow into the pipetting unit and at least one outlet in fluid communication with the reaction measurement unit (10) to allow the sample of water and the reagent to be pipetted into the reaction measurement unit (10) via the at least one outlet;

characterized in that the liquid taking and delivering unit further comprises a quantitative element for quantifying the water sample and/or the reagent, the quantitative element comprising:

a dosing fluid line (30), said dosing fluid line (30) having a fixed total line volume and being configured to be selectively in fluid communication with said at least one inlet and said at least one outlet of said tapping unit, wherein when said dosing fluid line (30) is in fluid communication with said at least one inlet, said sample of water and/or said reagent can flow into said dosing fluid line (30), and when said dosing fluid line (30) is in fluid communication with said at least one outlet, said tapping unit can feed a volume of said sample of water and/or said reagent corresponding to said fixed total line volume into said reaction measurement unit (10).

2. A water quality analyzer according to claim 1 wherein the liquid pick-up unit comprises a multi-way selector valve (50), the multi-way selector valve (50) comprising the at least one inlet and the at least one outlet, the dosing fluid line (30) being configured for direct fluid connection with the multi-way selector valve (50) to enable selective fluid communication with the at least one inlet and the at least one outlet.

3. A water quality analyser as claimed in claim 2 wherein the dosing element further comprises an optical sensor (20), the optical sensor (20) being arranged at a fixed location along the length of the dosing fluid conduit (30) to enable optical dosing of the sample water and/or the reagent to a volume corresponding to the conduit volume of the dosing fluid conduit (30) between the multi-way selector valve (50) and the fixed location.

4. A water quality analyser as claimed in any one of claims 2 to 3 wherein the multi-way selector valve (50) further comprises a common port (52), the common port (52) being in selective fluid communication with the at least one inlet and the at least one outlet, one end of the dosing fluid line (30) being connected to the common port (52).

5. A water quality analyser according to claim 4 wherein the other end of the dosing fluid line (30) is selectively in fluid communication with a first flow path (60) or a second flow path (70), a first pump being arranged on the first flow path (60) and a second pump being arranged on the second flow path (70), the first pump and the second pump being in opposite pumping directions.

6. A water quality analyser as claimed in claim 5 wherein the first pump is an aspiration pump (62) to draw the sample of water and/or the reagent into the dosing fluid conduit (30) when in fluid communication with the dosing fluid conduit (30) and the second pump is an air-blast pump (72) to pump a measured quantity of the sample of water and/or the reagent out of the dosing fluid conduit (30) when in fluid communication with the dosing fluid conduit (30).

7. A water quality analyzer according to claim 6 wherein the other end of the constant volume fluid line (30) is connected to the first flow path (60) and the second flow path (70) by means of a three-way joint (80).

8. A water quality analyser as claimed in claim 7 wherein a fluid valve (74) is arranged on the second flow path between the tee fitting (80) and the second pump, the fluid valve (74) being for selectively connecting and disconnecting the second pump to the dosing fluid line (30).

9. A water quality analyzer as claimed in claim 8 wherein the port of the tee fitting fluidly connected to the second flow path is integrated into the body of the fluid valve (74).

10. A water quality analyser as claimed in claim 5 wherein the first flow path (60) is selectively connectable to a waste unit (90) for discharging waste into the waste unit (90) via the dosing fluid conduit (30) and the first flow path (60).

11. An online water quality monitoring system comprising the water quality analyzer (100) of claim 1, a water sample storage container, at least one reagent reservoir, and a waste reservoir (92), wherein the water quality analyzer (100) comprises an interface in fluid connection with the waste reservoir (92), the water sample storage container, and the reagent reservoir.

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