Trace chloride ion detection and analysis system and method based on conductivity detection method

Abstract

The invention discloses a trace chloride ion detection and analysis system and method based on a conductivity detection method. The trace chloride ion detection and analysis system comprises a water inlet pipeline, an electric automatic regeneration cation exchange unit, a degassing unit, a chloride ion selective membrane and a micro-flow type conductivity detection unit, the water inlet pipeline is communicated with an inlet of the electric automatic regeneration cation exchange unit, an outlet of the electric automatic regeneration cation exchange unit is communicated with an inlet of the degassing unit, and an outlet of the degassing unit is connected with the micro-flow type conductivity detection unit through a chloride ion selective membrane. And the method has the characteristics of high detection efficiency, low cost and simple system.

Description

Technical Field

[0001] The invention belongs to the field of water quality detection and analysis, and relates to a trace chloride ion detection and analysis system and method based on a conductivity detection method. Background Art

[0002] For generator sets and steam power equipment, chloride ions are the most harmful active anions in the water vapor system. Trace amounts of chloride ions are enough to destroy the oxide protective film on the metal surface, causing corrosion of the equipment. Therefore, the effective detection of trace chloride ions is critical to monitoring changes in water vapor quality, adjusting operating conditions, and ensuring the safe operation of thermal systems.

[0003] At present, the main methods for determining chloride ions include titration, ion chromatography, and optical detection. Titration mainly detects constant-level chloride ions, and the detection range is usually 5-150 mg / L, and it cannot accurately measure trace-level chloride ions; ion chromatography detection technology can accurately detect trace-level chloride ions, but it is expensive, the system is complex, the maintenance cost is high, the measurement workload is large, and online measurement cannot be achieved; the optical detection method based on color development reaction can also detect trace-level chloride ions through concentration and enrichment technology, but it needs to add chemical substances such as reactants and color developers. In order to meet certain environmental protection requirements, the measurement waste liquid needs to be harmlessly treated, and due to the need for concentration and enrichment, the measurement cycle is often more than 1 hour. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a trace chloride ion detection and analysis system and method based on conductivity detection method, which can accurately detect the concentration of trace chloride ions and has the characteristics of high detection efficiency, low cost and simple system.

[0005] To achieve the above object, the present invention discloses a trace chloride ion detection and analysis system based on conductivity detection method, comprising a water inlet pipeline, an electric automatic regeneration cation exchange unit, a degassing unit, a chloride ion selective membrane and a micro-flow conductivity detection unit;

[0006] The water inlet pipeline is connected to the inlet of the electric automatic regeneration cation exchange unit, the outlet of the electric automatic regeneration cation exchange unit is connected to the inlet of the degassing unit, and the outlet of the degassing unit is connected to the micro-flow conductivity detection unit through the chloride ion selective membrane.

[0007] The further improvement of the trace chloride ion detection and analysis system based on the conductivity detection method of the present invention is:

[0008] Furthermore, it also includes a controller, which is connected to the electric automatic regeneration cation exchange unit 1 and the micro-flow conductivity detection unit.

[0009] Furthermore, the degassing unit adopts a hollow fiber membrane structure.

[0010] Furthermore, the chloride ion selective membrane is a hollow fiber membrane structure.

[0011] The present invention discloses a trace chloride ion detection and analysis method based on conductivity detection method, comprising the following steps:

[0012] The water sample passes through the electric automatic regeneration cation exchange unit, degassing unit, chloride ion selective membrane and micro-flow conductivity detection unit in sequence;

[0013] The conductivity measurement value DD of the water sample is detected by a micro-flow conductivity detection unit;

[0014] The chloride ion mass concentration of the water sample is calculated according to the conductivity measurement value DD of the water sample.

[0015] The further improvement of the trace chloride ion detection and analysis method based on conductivity detection method described in the present invention is:

[0016] Furthermore, the chloride ion mass concentration c (μg / L) = 35500·c Cl , where c Cl =(DD-0.055) / (A H +A Cl ), A H is the limiting molar conductivity of hydrogen ions, A Cl is the limiting molar conductivity of chloride ions.

[0017] Furthermore, the degassing unit adopts a hollow fiber membrane structure.

[0018] Furthermore, the chloride ion selective membrane is a hollow fiber membrane structure.

[0019] The present invention discloses a computer device, comprising a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the trace chloride ion detection and analysis method based on the conductivity detection method are implemented.

[0020] The present invention discloses a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the trace chloride ion detection and analysis method based on the conductivity detection method are implemented.

[0021] The present invention has the following beneficial effects:

[0022] In the specific operation of the trace chloride ion detection and analysis system and method based on the conductivity detection method described in the present invention, the water sample is sequentially passed through the electric automatic regeneration cation exchange unit, the degassing unit, the chloride ion selective membrane and the microflow conductivity detection unit, the conductivity measurement value DD of the water sample is detected by the microflow conductivity detection unit, and the chloride ion mass concentration of the water sample is calculated according to the conductivity measurement value DD of the water sample, and the system has the characteristics of high detection efficiency, low cost and simple system. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0024] Figure 1 It is a structural diagram of the present invention.

[0025] Among them, 1 is an electric automatic regeneration cation exchange unit, 2 is a degassing unit, 3 is a chloride ion selective membrane, and 4 is a microflow conductivity detection unit. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be understood that the terms “include” and “comprises” indicate the presence of described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0028] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0029] It should be further understood that the term "and / or" used in the present specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects are in an "or" relationship.

[0030] It should be understood that, although the terms first, second, third, etc. may be used to describe preset ranges, etc. in the embodiments of the present invention, these preset ranges should not be limited to these terms. These terms are only used to distinguish preset ranges from each other. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0031] The word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0032] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can usually be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0033] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0034] Embodiment 1

[0035] refer to Figure 1 The trace chloride ion detection and analysis system based on the conductivity detection method of the present invention comprises a water inlet pipeline, an electric automatic regeneration cation exchange unit 1, a degassing unit 2, a chloride ion selective membrane 3 and a micro-flow conductivity detection unit 4;

[0036] The water inlet pipe is connected to the inlet of the electric automatic regeneration cation exchange unit 1, the outlet of the electric automatic regeneration cation exchange unit 1 is connected to the inlet of the degassing unit 2, and the outlet of the degassing unit 2 is connected to the micro-flow conductivity detection unit 4 through the chloride ion selective membrane 3.

[0037] In this embodiment, a controller is also included, and the controller is connected to the electric automatic regeneration cation exchange unit 1 and the micro-flow conductivity detection unit 4 .

[0038] It should be noted that the electrically regenerated cation exchange unit 1 is used to remove all cations in the water sample (removal rate is higher than 99.9%). On the one hand, it can avoid the interference of cations on the measurement of chloride ions. On the other hand, it forms an acidic environment. The carbonate ions and bicarbonate ions in the water sample form carbonic acid or carbon dioxide, which is beneficial to the next step of removing inorganic carbon (carbon dioxide and its dissolved products) in the water sample.

[0039] The degassing unit 2 is based on high-efficiency degassing membrane separation technology and adopts a hollow fiber membrane structure. The water sample flows on the tube side and the degassing medium (high-purity water or vacuum) flows on the shell side. The degassing unit 2 can remove inorganic carbon (carbon dioxide and its dissolved products) in the water sample.

[0040] The chloride ion selective membrane 3 is a hollow fiber membrane structure. With the voltage difference as the driving force, the chloride ion selective membrane 3 selectively passes the chloride ions, and absorbs the chloride ions with an equal volume of high-purity water on the other side of the chloride ion selective membrane 3 .

[0041] The micro-flow conductivity detection unit 4 is used to detect the conductivity of the water sample.

[0042] The trace chloride ion detection and analysis method based on conductivity detection method of the present invention comprises the following steps:

[0043] The water sample flows through the electric automatic regeneration cation exchange unit 1 at a certain flow rate (2-10 mL / min) to remove cations in the water sample. It should be noted that the electric automatic regeneration cation exchange unit 1 can efficiently remove cations in the water sample, avoid the influence of cations on the measurement of chloride ions, and form an acidic environment for the water sample. At this time, the carbonate ions in the water sample and the bicarbonate ions form carbonic acid or carbon dioxide, which is conducive to the next step of removing inorganic carbon in the water sample, that is, carbon dioxide and its dissolved products;

[0044] The water sample outputted by the electric automatic regeneration cation exchange unit 1 enters the degassing unit 2, and the inorganic carbon in the water sample is effectively removed by the degassing unit 2. The reason for removing carbon dioxide is that the chloride ion selective membrane 3 can selectively pass chloride ions and gases, and carbon dioxide and its dissolved products can generate conductivity. In order to avoid the influence caused by this part, the inorganic carbon in the water sample, that is, carbon dioxide and its dissolved products, should be removed in advance;

[0045] The effluent of the degassing unit 2 enters the chloride ion selective membrane 3, and the water sample flows through the tube side of the hollow fiber membrane. Under the driving force of the voltage difference (3-5V DC voltage), the chloride ions selectively pass through the chloride ion selective membrane 3 and enter the shell side. The shell side flows through high-purity water with an equal flow rate (2-10mL / min) and dissolves the chloride ions passing through, wherein the chloride ions and the hydrogen ions of equal concentration generated by the shell side voltage positive electrode hydrolysis form a hydrochloric acid (HCl) solution;

[0046] The high-purity water carrying chloride ions enters the micro-flow conductivity detection unit 4 , and the conductivity measurement value DD of the water sample is measured by the micro-flow conductivity detection unit 4 .

[0047] It should be noted that the measured DD is contributed by HCl in pure water. Since the chloride ion content of the water vapor system is low, it can be regarded as an infinitely diluted aqueous solution. The chloride ion content can be calculated based on the limiting molar conductivity data of different ions, specifically:

[0048] DD(μS / cm)=0.055+c H ·A H +c Cl ·A Cl

[0049] Among them, c H is the molar concentration of hydrogen ions (mmol / L), A H is the limiting molar conductivity of hydrogen ions (349.9S·cm 2 / mol), c Cl is the molar concentration of chloride ions (mmol / L), A Cl is the limiting molar conductivity of chloride ions (76.3S·cm 2 / mol), c H =c Cl .

[0050] Therefore, c Cl =(DD-0.055) / (A H +A Cl );

[0051] Therefore, the chloride ion mass concentration c (μg / L) = 35500·c Cl .

[0052] In addition to being able to accurately measure chloride ions, the present invention can expand a microfluidic conductivity detection unit 4 behind the electric automatic regeneration cation exchange unit 1 and the degassing unit 2 in the present invention to detect the hydrogen conductivity and degassed hydrogen conductivity index of the water sample.

[0053] It should be noted that the present invention is based on the conductivity detection method (physical detection method), which avoids the need to add chemical reagents in the chemical detection method, has a simple structure, and has good stability and accuracy.

[0054] Embodiment 2

[0055] The specific process of this embodiment is as follows:

[0056] 1) A sample flows through the electric automatic regeneration cation exchange unit 1 at a flow rate of 5 mL / min to remove cations in the water and convert them into hydrogen ions;

[0057] 2) After the cations are removed from the water sample, the effluent from the electrically regenerated cation exchange unit 1 enters the degassing unit 2, and the inorganic carbon in the water sample is effectively removed;

[0058] 3) The outlet water of the degassing unit 2 enters the chloride ion selective membrane 3, and the water sample flows through the hollow fiber membrane tube side. Under the driving force of the voltage difference (4V DC voltage), the chloride ions selectively pass through the membrane into the shell side. High-purity water with an equal flow rate (5mL / min) flows through the shell side and dissolves the chloride ions passing through. The chloride ions therein are hydrolyzed with the hydrogen ions of equal concentration produced by the positive electrode of the shell side voltage to form a hydrochloric acid (HCl) solution.

[0059] 4) The high-purity water carrying chloride ions enters the micro-flow conductivity detection unit 4 to measure the conductivity measurement value DD in the water sample to be 0.122 μS / cm;

[0060] 5) According to the calculation method, the chloride ion concentration in the water sample is: c (μg / L) = 35500 ×

[0061] (0.122-0.055) / (349.9+76.3)=5.58 μg / L, which is close to the result of 5.63 measured by ion chromatography, and the measurement deviation is less than 1%.

[0062] Embodiment 3

[0063] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the trace chloride ion detection and analysis method based on the conductivity detection method are implemented, for example, including: the water sample is sequentially passed through an electric automatic regeneration cation exchange unit 1, a degassing unit 2, a chloride ion selective membrane 3, and a microfluidic conductivity detection unit 4; the conductivity measurement value DD of the water sample is detected by the microfluidic conductivity detection unit 4; the chloride ion mass concentration of the water sample is calculated according to the conductivity measurement value DD of the water sample. Wherein, the memory may include a memory, such as a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk memory, etc.; the processor, the network interface, and the memory are interconnected through an internal bus, and the internal bus may be an industrial standard architecture bus, a peripheral component interconnection standard bus, an extended industrial standard architecture bus, etc., and the bus may be divided into an address bus, a data bus, a control bus, etc. The memory is used to store programs. Specifically, the program may include a program code, and the program code includes computer operation instructions. The memory may include a memory and a non-volatile memory, and provide instructions and data to the processor.

[0064] Embodiment 4

[0065] A computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, wherein when the computer program is executed by a processor, the steps of the trace chloride ion detection and analysis method based on the conductivity detection method are implemented, for example, including: the water sample is sequentially passed through an electric automatic regeneration cation exchange unit 1, a degassing unit 2, a chloride ion selective membrane 3 and a microfluidic conductivity detection unit 4; the conductivity measurement value DD of the water sample is detected by the microfluidic conductivity detection unit 4; the chloride ion mass concentration of the water sample is calculated according to the conductivity measurement value DD of the water sample. Specifically, the computer-readable storage medium includes, but is not limited to, for example, volatile memory and / or non-volatile memory. The volatile memory may include a random access memory (RAM) and / or a cache memory (cache), etc. The non-volatile memory may include a read-only memory (ROM), a hard disk, a flash memory, an optical disk, a magnetic disk, etc.

[0066] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0067] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0068] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0069] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0070] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and disclosure of the invention. This application is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. The specification and examples are to be considered exemplary only, and the true scope and spirit of the present invention are indicated by the following claims.

[0071] It should be understood that the present invention is not limited to the exact construction that has been described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

[0072] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A trace chloride ion detection and analysis system based on conductivity detection method, characterized in that: It comprises a water inlet pipeline, an electric automatic regeneration cation exchange unit (1), a degassing unit (2), a chloride ion selective membrane (3) and a micro-flow conductivity detection unit (4); The water inlet pipeline is connected to the inlet of the electric automatic regeneration cation exchange unit (1), the outlet of the electric automatic regeneration cation exchange unit (1) is connected to the inlet of the degassing unit (2), and the outlet of the degassing unit (2) is connected to the micro-flow conductivity detection unit (4) via the chloride ion selective membrane (3).

2. The trace chloride ion detection and analysis system based on conductivity detection method according to claim 1, characterized in that: It also comprises a controller, which is connected to the electric automatic regeneration cation exchange unit (1) and the micro-flow conductivity detection unit (4).

3. The trace chloride ion detection and analysis system based on conductivity detection method according to claim 1, characterized in that: The degassing unit (2) adopts a hollow fiber membrane structure.

4. The trace chloride ion detection and analysis system based on conductivity detection method according to claim 1, characterized in that: The chloride ion selective membrane (3) is a hollow fiber membrane structure.

5. A trace chloride ion detection and analysis method based on conductivity detection method, characterized in that: The trace chloride ion detection and analysis system based on the conductivity detection method according to claim 1 comprises the following steps: The water sample is sequentially passed through an electric automatic regeneration cation exchange unit (1), a degassing unit (2), a chloride ion selective membrane (3) and a micro-flow conductivity detection unit (4); Detecting a conductivity measurement value DD of the water sample by a microfluidic conductivity detection unit (4); The chloride ion mass concentration of the water sample is calculated according to the conductivity measurement value DD of the water sample.

6. The trace chloride ion detection and analysis method based on conductivity detection method according to claim 5, characterized in that: Chloride ion mass concentration c(μg / L)=35500·c Cl , where c Cl =(DD-0.055) / (A H +A Cl ), A H is the limiting molar conductivity of hydrogen ions, A Cl is the limiting molar conductivity of chloride ions.

7. The trace chloride ion detection and analysis method based on conductivity detection method according to claim 5, characterized in that: The degassing unit (2) adopts a hollow fiber membrane structure.

8. The trace chloride ion detection and analysis method based on conductivity detection method according to claim 5, characterized in that: The chloride ion selective membrane (3) is a hollow fiber membrane structure.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the trace chloride ion detection and analysis method based on the conductivity detection method as described in any one of claims 5 to 8 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the trace chloride ion detection and analysis method based on conductivity detection method as described in any one of claims 5 to 8 are implemented.

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