阅读说明：本技术 一种低浓度微量水样pH电导检测器 (Low-concentration trace water sample pH conductivity detector ) 是由 龚真 崔海松 魏峰 黄格 于 2020-12-25 设计创作，主要内容包括：本发明公开了一种低浓度微量水样pH电导检测器,包括蠕动泵、用于安装电导电极的电导检测座、用于安装pH电极的pH检测座以及与大气环境连通的三通阀,电导检测座和pH检测座上均设有底部连通孔和侧面连通孔；电导检测座的底部连通孔与蠕动泵连通,电导检测座的侧面连通孔和pH检测座的底部连通孔之间设有检测座连通管路,pH检测座的侧面连通孔与三通阀连接；电导检测座和pH检测座均为密封结构。电导检测座和pH检测座下进侧出的结构,在检测时能够利用气体阻隔两个检测座内的待测水样,并在蠕动泵反转排液时顺利排出全部水样,避免了pH电极测量产生的钠离子进入电导检测座内,实现了对低浓度微量水样的pH电导精确测量。(The invention discloses a low-concentration trace water sample pH conductivity detector, which comprises a peristaltic pump, a conductivity detection seat for mounting a conductivity electrode, a pH detection seat for mounting the pH electrode and a three-way valve communicated with the atmospheric environment, wherein the conductivity detection seat and the pH detection seat are respectively provided with a bottom communicating hole and a side communicating hole; the bottom communicating hole of the conductivity detection seat is communicated with the peristaltic pump, a detection seat communicating pipeline is arranged between the side communicating hole of the conductivity detection seat and the bottom communicating hole of the pH detection seat, and the side communicating hole of the pH detection seat is connected with the three-way valve; the conductivity detection seat and the pH detection seat are both sealing structures. The structure that the electric conductance detects seat and pH and detect the seat and advance the side and go out down can utilize two water samples that await measuring that detect in the seat of gas separation when detecting to discharge all water samples smoothly when the peristaltic pump reversal flowing back, avoided in the sodium ion that the pH electrode measurement produced gets into the electric conductance detection seat, realized the pH electric conductance accurate measurement to low concentration trace water sample.)

1. A low-concentration trace water sample pH conductivity detector is characterized by comprising a peristaltic pump (1), a conductivity detection seat for installing a conductivity electrode (6), a pH detection seat for installing a pH electrode (7) and a three-way valve (5) communicated with the atmospheric environment, wherein the conductivity detection seat and the pH detection seat are respectively provided with a bottom communicating hole (21) and a side communicating hole (22);

the bottom communicating hole (21) of the conductivity detection seat is communicated with the peristaltic pump (1), a detection seat communicating pipeline (4) is arranged between the side communicating hole (22) of the conductivity detection seat and the bottom communicating hole (21) of the pH detection seat, and the side communicating hole (22) of the pH detection seat is connected with the three-way valve (5);

the conductivity detection seat and the pH detection seat are both sealing structures.

2. The pH conductivity detector for the low-concentration trace water sample according to claim 1, wherein the conductivity detection seat and the pH detection seat comprise a detection seat (2) and a sealing cover (3) for sealing the detection seat (2), and the sealing cover (3) is arranged on the upper end face of the detection seat (2).

3. The pH conductivity detector for low-concentration trace water samples according to claim 2, wherein the detection seat (2) is cylindrical, and the inner diameter of the detection seat (2) is larger than the outer diameter of the conductivity electrode (6) or the outer diameter of the pH electrode (7).

4. The detector according to claim 2, wherein the three-way valve (5) comprises a liquid inlet (53), a waste liquid port (52) and a pressure balancing port (51), the pressure balancing port (51) is used for communicating with the atmosphere, and the liquid inlet (53) is communicated with the side communication hole (22) of the pH detection seat.

5. The detector for detecting the pH conductance of a low-concentration trace water sample according to any one of claims 2 to 4, wherein one of the sealing cover (3) and the detection seat (2) is provided with a positioning groove, and the other one is provided with a positioning block clamped with the positioning groove.

6. The detector of pH conductivity of low-concentration trace water sample according to claim 5, wherein the axis of the bottom communication hole (21) is collinear with the axis of the detection seat (2).

7. The pH conductivity detector for low-concentration trace water samples according to claim 5, wherein the side communication hole (22) is arranged at one end of the detection seat (2) relatively close to the sealing cover (3).

Technical Field

The invention relates to the technical field of water sample detection, in particular to a low-concentration trace water sample pH conductivity detector.

Background

The pH and conductivity of the water sample are mostly detected by adopting a flow cell installation method, namely, the water sample is introduced into a detection container by using a peristaltic pump, and a pH electrode and a conductivity electrode are inserted for measurement.

Because the pH electrode is sodium glass or lithium glass, the pH electrode can release sodium ions after being placed in water, thereby interfering with the conductivity measurement of a water sample. In order to eliminate the interference of pH measurement on conductivity measurement, a pH electrode and a conductivity electrode are generally arranged separately, and the measurement interference is reduced by increasing the distance between the two electrodes, so that the measurement method has extremely high requirement on the water quantity of a water sample, and cannot be used when the concentration of the water sample to be measured is low or the volume of the water sample to be measured is small.

In summary, how to realize accurate pH conductance measurement of a low-concentration trace water sample is a problem to be solved urgently by those skilled in the art.

Disclosure of Invention

In view of this, the present invention provides a low-concentration trace water sample pH conductance detector, which can isolate a conductance electrode from a pH electrode by using gas, avoid interference of the pH electrode on the low-concentration trace water sample conductance measurement, and realize accurate measurement of the pH conductance of the low-concentration trace water sample.

In order to achieve the above purpose, the invention provides the following technical scheme:

a low-concentration trace water sample pH conductivity detector comprises a peristaltic pump, a conductivity detection seat for mounting a conductivity electrode, a pH detection seat for mounting the pH electrode and a three-way valve communicated with the atmospheric environment, wherein a bottom communicating hole and a side communicating hole are formed in each of the conductivity detection seat and the pH detection seat;

the bottom communicating hole of the conductivity detection seat is communicated with the peristaltic pump, a detection seat communicating pipeline is arranged between the side communicating hole of the conductivity detection seat and the bottom communicating hole of the pH detection seat, and the side communicating hole of the pH detection seat is connected with the three-way valve;

the conductivity detection seat and the pH detection seat are both sealing structures.

Preferably, the conductance detection seat and the pH detection seat both comprise a detection seat and a sealing cover for sealing the detection seat, and the sealing cover is arranged on the upper end surface of the detection seat.

Preferably, the detection seat is cylindrical, and the inner diameter of the detection seat is larger than the outer diameter of the conductance electrode or the outer diameter of the pH electrode.

Preferably, the three-way valve comprises a liquid inlet, a waste liquid port and a pressure balancing port, the pressure balancing port is used for communicating with the atmospheric environment, and the liquid inlet is communicated with the side communicating hole of the pH detection seat.

Preferably, one of the sealing cover and the detection seat is provided with a positioning groove, and the other one is provided with a positioning block clamped with the positioning groove.

Preferably, the axis of the bottom communication hole is collinear with the axis of the detection seat.

Preferably, the side communication hole is formed at an end of the detection seat relatively close to the sealing cover.

When the low-concentration trace water sample pH conductivity detector provided by the invention is used for measuring, a water sample to be measured is injected into a sample inlet of a peristaltic pump, the water sample to be measured sequentially enters a conductivity detection seat and a pH detection seat through the peristaltic pump, and the water sample to be measured which exceeds a side communication hole of the pH detection seat enters a three-way valve and is discharged from a waste liquid port; after liquid injection is finished, gas is introduced into the sample inlet, and because the density of the gas is less than that of a water sample to be detected, the gas is accumulated above the water sample to be detected and enters the detection seat communicating pipeline through the side communicating hole of the conductivity detection seat, an air isolation column is formed in the detection seat communicating pipeline, and the water sample to be detected in the conductivity detection seat and the pH detection seat is isolated; after the detection is finished, the peristaltic pump is controlled to rotate reversely, air enters the pH detection seat through the three-way valve, and a water sample to be detected in the pH detection seat is pressed into a detection seat communicating pipeline, so that the water sample to be detected after the detection is finished is discharged from a sample inlet of the peristaltic pump.

Therefore, the structures of the lower inlet side and the lower outlet side of the conductivity detection seat and the pH detection seat can utilize gas to block a water sample to be detected in the conductivity detection seat and a water sample to be detected in the pH detection seat during detection, and smoothly discharge all the water samples during reverse liquid discharge of the peristaltic pump, so that sodium ions generated by pH electrode measurement are prevented from entering the conductivity detection seat, and the accurate measurement of the pH conductivity of a low-concentration trace water sample is realized.

Meanwhile, the structure of the lower inlet and the side outlet ensures that when the peristaltic pump excessively pumps liquid or the volume of a water sample to be detected is too small, air enters the pH detection seat, so that the pH electrode is not arranged in a dry mode, and fault damage caused by the dry arrangement of the pH electrode is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a schematic structural diagram of an embodiment of the pH conductivity detector for a low-concentration trace water sample according to the present invention;

fig. 2 is a schematic structural diagram of the assembled low-concentration trace water sample pH conductivity detector and multi-channel option valve in fig. 1.

In fig. 1-2:

the device comprises a peristaltic pump 1, a detection seat 2, a bottom communicating hole 21, a side communicating hole 22, a sealing cover 3, a detection seat communicating pipeline 4, a three-way valve 5, a pressure balancing port 51, a waste liquid port 52, a liquid inlet 53, a conductance electrode 6, a pH electrode 7, a multi-channel option valve 8, a cleaning channel 81, an electrical guide label liquid channel 82, a pH label liquid channel 83, an online sample channel 84, an offline sample channel 85 and an air channel 86.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The core of the invention is to provide a low-concentration trace water sample pH conductivity detector, which can isolate a conductive electrode and a pH electrode by using gas, avoid the interference of the pH electrode on the conductivity measurement of the low-concentration trace water sample, and realize the accurate measurement of the pH conductivity of the low-concentration trace water sample.

Referring to fig. 1-2, fig. 1 is a schematic structural diagram of an embodiment of a low-concentration trace water sample pH conductance detector provided in the present invention; fig. 2 is a schematic structural diagram of the assembled low-concentration trace water sample pH conductivity detector and multi-channel option valve in fig. 1.

The low-concentration trace water sample pH conductivity detector provided by the embodiment comprises a peristaltic pump 1, a conductivity detection seat for mounting a conductivity electrode 6, a pH detection seat for mounting a pH electrode 7 and a three-way valve 5 communicated with the atmospheric environment, wherein a bottom communicating hole 21 and a side communicating hole 22 are respectively formed in the conductivity detection seat and the pH detection seat; the bottom communicating hole 21 of the conductivity detection seat is communicated with the peristaltic pump 1, a detection seat communicating pipeline 4 is arranged between the side communicating hole 22 of the conductivity detection seat and the bottom communicating hole 21 of the pH detection seat, and the side communicating hole 22 of the pH detection seat is connected with a three-way valve 5; the conductivity detection seat and the pH detection seat are both sealing structures.

Considering that sodium ions generated by the pH electrode detection method can influence the conductivity detection result, and the conductivity electrode detection method can not influence the pH detection result, the conductivity detection seat is arranged upstream of the pH detection seat, namely, when a water sample to be detected is added, the water sample to be detected flows into the pH detection seat from the conductivity detection seat.

Referring to fig. 1, the conductivity measuring seat and the pH measuring seat are used for installing a conductivity electrode 6 and a pH electrode 7, respectively, and both the conductivity measuring seat and the pH measuring seat are provided with a bottom communicating hole 21 and a side communicating hole 22.

In order to ensure the formation of the gas isolation column, the conductance detection seat and the pH detection seat are both sealing structures, preferably, in order to facilitate the installation of the conductance detection seat and the pH detection seat, the conductance detection seat and the pH detection seat both comprise a detection seat 2 and a sealing cover 3 for sealing the detection seat 2, and the sealing cover 3 is arranged on the upper end surface of the detection seat 2.

The conductance detects seat and pH and detects the seat and all can set up to hollow cylinder, hollow cuboid or other arbitrary geometric shapes, considers that conductance electrode 6 and pH electrode 7 are mostly cylindricly, and is preferred, detects seat 2 and can set up to cylindricly, and detects the internal diameter of seat 2 and be greater than the external diameter of conductance electrode 6 or the external diameter of pH electrode 7.

Because the height of the water sample to be detected is higher than the measurement height of the electrode during measurement, the inner diameter of the detection seat 2 is too large, the volume of the water sample to be detected is increased during detection, and the detection of a trace water sample is not facilitated. For the above reasons, it is preferable that the size of the detection holder 2 is the same as that of the original electrode cap of the conductivity electrode 6 or the pH electrode 7.

Preferably, the side communication hole 22 is provided at an end of the sensing seat 2 relatively close to the sealing cover 3. When the electrode is measured, the required measurement height is fixed, which is beneficial to reducing the height of the detection seat 2.

The height from the side communication hole 22 to the bottom surface of the detection seat 2 is determined according to the measurement height required by electrode measurement, so as to ensure that the height of the water sample to be measured in the detection seat 2 is higher than the measurement height.

Considering that the inner wall surface of the conductivity detection seat and the inner wall surface of the pH detection seat are directly contacted with the water sample to be detected, in order to avoid interfering with the experimental structure, the conductivity detection seat and the pH detection seat are both made of materials with stable chemical properties so as to avoid chemical reaction with the water sample to be detected.

The detection seat communicating pipeline 4 is connected with the conductivity detection seat and the pH detection seat, and the inner wall surface of the detection seat communicating pipeline 4 is also contacted with a water sample to be detected, so that the detection seat communicating pipeline 4 is also made of a material with stable chemical property, and the reaction with the water sample to be detected and the water sample pollution are avoided.

The three-way valve 5 is mainly used for discharging excessive water samples during excessive liquid adding and discharging liquid after the experiment is completed, referring to the figure, preferably, the three-way valve 5 comprises a liquid inlet 53, a waste liquid port 52 and a pressure balancing port 51, the pressure balancing port 51 is used for communicating with the atmospheric environment, and the liquid inlet 53 is communicated with the side communicating hole 22 of the pH detection seat.

During measurement, a water sample to be measured is injected into a sample inlet of the peristaltic pump 1, the water sample to be measured sequentially enters the conductivity detection seat and the pH detection seat through the peristaltic pump 1, and the water sample to be measured which exceeds the side communicating hole 22 of the pH detection seat enters the three-way valve 5 and is discharged from the waste liquid port 52; after the liquid injection is finished, introducing gas into the sample inlet, wherein the gas is accumulated above the water sample to be detected and enters the detection seat communicating pipeline 4 through the side communicating hole 22 of the conductivity detection seat because the density of the gas is less than that of the water sample to be detected, and an air isolating column is formed in the detection seat communicating pipeline 4 to isolate the water sample to be detected in the conductivity detection seat and the pH detection seat; after the detection is finished, the peristaltic pump 1 is controlled to rotate reversely, air enters the pH detection seat through the three-way valve 5, and a water sample to be detected in the pH detection seat is pressed into the detection seat communicating pipeline 4, so that the water sample to be detected after the detection is finished is discharged from the sample inlet of the peristaltic pump 1.

In this embodiment, the structure that advances the side and goes out under conductance detection seat and the pH detection seat can utilize the water sample that awaits measuring in the gas separation conductance detection seat and the water sample that awaits measuring in the pH detection seat when detecting to discharge all water samples smoothly when peristaltic pump 1 reversal flowing back, avoided in the sodium ion that the pH electrode measurement produced gets into the conductance detection seat, realized the pH conductance accurate measurement to low concentration trace water sample.

Meanwhile, the structure of the lower inlet and the side outlet ensures that when the peristaltic pump 1 excessively pumps liquid or the volume of a water sample to be detected is too small, air enters the pH detection seat, so that the pH electrode is not arranged in a dry mode, and the damage of dry faults of the pH electrode is reduced.

Preferably, the axis of the bottom communication hole 21 is collinear with the axis of the test seat 2.

On the basis of the above embodiment, one of the sealing cover 3 and the detecting seat 2 is provided with a positioning groove, and the other one is provided with a positioning block clamped with the positioning groove.

The positioning groove can be arranged on the upper end surface of the detection seat 2 and can be arranged on the inner wall surface of the upper end of the detection seat 2.

The positioning groove can be an annular groove arranged around the circumferential surface of the detection seat 2, and also can be one section or a plurality of sections of arc-shaped grooves.

The cross-sectional shape of the positioning groove can be set to be any geometric shape such as rectangle, triangle, trapezoid and the like.

In this embodiment, sealed lid 3 is connected with detecting 2 joint of seat, compares sealed lid 3 and directly places on detecting the up end of seat 2, connects stably, sealed lid 3 is difficult with detecting 2 separation of seat.

On the basis of the above embodiment, the sample inlet of the peristaltic pump 1 is connected to the multi-channel option valve 8, and the multi-channel option valve 8 includes a detection channel for adding and discharging a sample water to be detected and a cleaning channel 81 for adding and discharging pure water.

During detection, a detection channel of the multi-channel option valve 8 is opened, and a water sample to be detected enters the peristaltic pump 1; after the detection is finished and the water sample to be detected is completely discharged, a cleaning channel 81 of the multi-channel option valve 8 is opened, pure water enters the conductivity detection seat and the pH detection seat through the peristaltic pump 1, and after the pure water is soaked for a certain time, the peristaltic pump 1 is controlled to rotate reversely to discharge waste liquid; repeating the above process for 3 times to complete the cleaning of the conductivity detection seat and the pH detection seat; and soaking the conductive electrode 6 and the pH electrode 7 by using pure water to remove residual water samples on the surfaces of the electrodes so as to avoid interference on the next measurement.

In this embodiment, peristaltic pump 1 cooperation multichannel option valve 8 has realized automatic measurement and washing to low concentration trace water sample, and the simple operation is favorable to improving detection efficiency.

In one embodiment, referring to fig. 2, multi-channel selection valve 8 may include a wash channel 81, an electrically conductive label channel 82, a pH label channel 83, an online sample channel 84, an offline sample channel 85, and an air channel 86.

The cleaning channel 81 is used for adding pure water and cleaning the conductivity electrode 6 and the pH electrode 7 after detection is finished; the electric label liquid channel 82 and the pH label liquid channel 83 are respectively used for adding electric label liquid and pH label liquid so as to calibrate the conductive electrode 6 and the pH electrode 7 of the low-concentration trace water sample pH conductivity detector; the online sample channel 84 and the offline sample channel 85 are used for adding a water sample to be detected and are respectively used for online detection and offline detection; the air channel 86 is used for inputting air into the pH detection seat when the volume of the water sample to be detected is too small so as to prevent the pH electrode 7 from being dried to cause the pH electrode to be in fault.

Therefore, the low-concentration trace water sample pH conductivity detector provided by the embodiment realizes automatic calibration, automatic detection and automatic cleaning, can be suitable for two different detection modes of online detection and offline detection, and has a wide application range.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The pH conductivity detector for the low-concentration trace water sample provided by the invention is described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.