KR20200035584A - Corrosion monitoring sensor using electrochemical noise and corrosion monitoring device using the same - Google Patents

Abstract

The present invention relates to a corrosion monitoring sensor using electrochemical noise and a corrosion monitoring apparatus using the same. The corrosion monitoring sensor using the electrochemical noise according to an embodiment of the present invention includes: a sensing unit for sensing changes in voltage and current over time in an electrochemical reaction to a target structure; and a signal process unit for measuring voltage and current signals by using a sensing result.

Description

Corrosion monitoring sensor using electrochemical noise and corrosion monitoring device using the same {CORROSION MONITORING SENSOR USING ELECTROCHEMICAL NOISE AND CORROSION MONITORING DEVICE USING THE SAME}

The present invention relates to a corrosion monitoring sensor using an electrochemical noise and a corrosion monitoring device using the same, and more particularly, by directly measuring the voltage and current signals by directly contacting the target structure, and measuring the electrochemical noise, to the target structure in real time. A corrosion monitoring sensor using electrochemical noise and a corrosion monitoring device using the same to derive a noise resistance and corrosion rate.

In general, 'biomass (biomass)' refers to an organism, such as plants, animals, and microorganisms that can be used as chemical energy, that is, an energy source of bioenergy, and biomass fuel is gas, liquid, produced from biomass, Refers to a solid form of fuel, for example, bioethanol, biodiesel, biojet fuel, and the like.

In a boiler furnace using biomass fuel, corrosion problems are seriously caused by a combustion environment different from the combustion characteristics of a conventional coal boiler furnace.

In other words, these biomass fuels are cheaper than fossil fuels, but low combustion rate, high moisture content, various chemical compositions, and large amounts of alkali chlorides are discharged as combustion gases during combustion, and are deposited on superheater tubes to lower thermal conductivity and severe corrosion. This can cause problems and significantly increase maintenance costs.

Existing corrosion detection methods mainly measure the resistance to corrosion using a probe of the same material as the structure or steel to be measured, or measure the environmental factors placed on the structure or steel to estimate the resistance to corrosion. Was used.

However, even in the case of a probe made of a material such as a structure or a steel, this method cannot accurately measure corrosion resistance due to a different state of the material depending on the exposed environment, and it is difficult to measure corrosion resistance in real time.

Therefore, the existing corrosion detection method requires a technique capable of measuring corrosion information in real time in a direct manner and providing the result.

Republic of Korea Registered Patent Publication No. 10-1207612 (2012.11.27 registration)

An object of the present invention is to measure the electrochemical noise by directly detecting the voltage and current signals by directly contacting the target structure, and in order to derive a noise resistance and corrosion rate for the target structure in real time, a corrosion monitoring sensor using electrochemical noise and It is to provide a corrosion monitoring device using this.

Corrosion monitoring sensor using electrochemical noise according to an embodiment of the present invention, a sensing unit for sensing a change over time of the voltage and current in the electrochemical reaction to the target structure; And a signal processing unit for measuring voltage and current signals using the sensing result.

The sensing unit includes an electrolyte region unit filled with an electrolyte solution for an electrochemical reaction; An electrode inserted into the electrolyte solution to sense a change in voltage and current over time; And a membrane member for exchanging electrolyte ions between the electrolyte solution and the target structure.

The electrode may be any one of platinum (pt), carbon rod, saturated calomel electrode (SCE), and silver / silver chloride electrode (Ag-AgCl electrode).

The membrane member is polyvinylidene fluoride-hexafluoropropylene (PolyVinylidene Fluoride-HexaFluoroPropyl, PVdF-HFP) copolymer, polyvinylidene fluoride, polysulfone, polyether sulfone, polyether sulfone Poly-Tera FluoroEthylene (PTFE), polyethylene, polycarbonate, polypropylene, polyvinylalcohol, polyphenylene sulfide, cellulose acetate ), Polyamide (polyamide), polyacrylonitrile (polyacrylonitrile), or the like may be selected or used from the group consisting of two or more.

According to an embodiment, a frame formed by opening the lower surface of the electrolyte region, and sealed by the membrane member; And a frame stopper for fixing the membrane member to the frame.

The frame may be any of Teflon, epoxy resin, and rubber material.

The sensing unit and the signal processing unit may be electrically connected to each other through a pin connector.

According to an embodiment, a sensor case including a case body that installs the sensing unit on an upper side and a signal body which installs the signal processing unit on a lower side, and a case cover that seals the case body, further includes a outer surface of the sensing unit. And it may be that the O-ring is inserted between the inner surface of the case body.

In addition, the corrosion monitoring apparatus according to an embodiment of the present invention measures voltage and current signals using a sensing unit for sensing changes in voltage and current over time in an electrochemical reaction to a target structure and the sensing results. Corrosion monitoring sensor including a signal processing unit for; A control unit for calculating noise resistance and corrosion rate from the measured voltage and current signals; And an output unit for outputting the calculated noise resistance and corrosion rate.

The control unit may calculate noise resistance by using a potential standard deviation and a current standard deviation.

The controller may calculate the corrosion rate by applying the calculated noise resistance to an electrochemical tarfel measurement method.

The control unit may be to check the corrosion type by calculating a localization index using the measured voltage and current signals.

According to the present invention, noise resistance and corrosion rate for a target structure can be derived in real time by measuring voltage and current signals by directly contacting the target structure and measuring electrochemical noise.

In addition, the present invention can provide the results by measuring corrosion information in a real-time manner in real time.

1 is a view showing a corrosion monitoring sensor using electrochemical noise according to an embodiment of the present invention,
Figure 2 is a view showing the sensing unit of Figure 1,
3 is a view showing the signal processing unit of FIG. 1,
4 is a view showing the voltage and current signals measured in the ZRA of FIG. 3,
5 is a view showing a corrosion monitoring apparatus using a corrosion monitoring sensor according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, in the following description and accompanying drawings, detailed descriptions of well-known functions or configurations that may obscure the subject matter of the present invention are omitted. In addition, it should be noted that the same components throughout the drawings are indicated by the same reference numerals as much as possible.

The terms or words used in the present specification and claims described below should not be interpreted as being limited to ordinary or dictionary meanings, and the inventor appropriately defines terms as terms for explaining his or her invention in the best way. Based on the principle that it can be done, it should be interpreted as a meaning and a concept consistent with the technical idea of the present invention.

Therefore, the embodiments shown in the embodiments and drawings described in this specification are only the most preferred embodiments of the present invention, and do not represent all of the technical spirit of the present invention, and thus can replace them at the time of application. It should be understood that there may be equivalents and variations.

In the accompanying drawings, some components are exaggerated, omitted, or schematically illustrated, and the size of each component does not entirely reflect the actual size. The present invention is not limited by the relative size or spacing drawn in the accompanying drawings.

When a part of the specification "includes" a certain component, this means that other components may be further included instead of excluding other components unless specifically stated otherwise. In addition, when a part is said to be "connected" to another part, this includes not only "directly connected" but also "electrically connected" with other elements in between.

Singular expressions include plural expressions unless the context clearly indicates otherwise. The terms "include" or "have" are intended to indicate the presence of features, numbers, steps, actions, components, parts or combinations thereof described in the specification, one or more other features or numbers or steps. It should be understood that it does not preclude the existence or addition possibility of the operation, components, parts or combinations thereof.

Also, the term "part" used in the specification means a hardware component such as software, FPGA, or ASIC, and "part" performs certain roles. However, "part" is not meant to be limited to software or hardware. The "unit" may be configured to be in an addressable storage medium or may be configured to reproduce one or more processors. Thus, as an example, "part" refers to components such as software components, object-oriented software components, class components and task components, processes, functions, attributes, procedures, Includes subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, database, data structures, tables, arrays and variables. The functionality provided within components and "parts" can be combined into a smaller number of components and "parts" or further separated into additional components and "parts".

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains may easily practice. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. In addition, in order to clearly describe the present invention in the drawings, parts irrelevant to the description are omitted, and like reference numerals are assigned to similar parts throughout the specification.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a view showing a corrosion monitoring sensor using electrochemical noise according to an embodiment of the present invention.

As shown in FIG. 1, a corrosion monitoring sensor (hereinafter referred to as a 'corrosion monitoring sensor') 1 using electrochemical noise according to an embodiment of the present invention detects voltage and current signals by directly contacting a target structure. To measure electrochemical noise.

Here, the term “electrochemical noise” refers to a change over time of the current or voltage in the electrochemical reaction, and may be analyzed as noise resistance generated during the electrochemical reaction. Then, the noise resistance is used to derive the reaction rate (corrosion rate) for the electrochemical reaction around the electrode.

Meanwhile, in the corrosion monitoring sensor 1, a signal processing unit 30 and a sensing unit 100 electrically interconnected through a pin connector 20 are installed inside the sensor case 10. Here, the signal processing unit 30 and the sensing unit 100 are stacked apart from each other with the pin connector 20 therebetween.

In addition, since each of the signal processing unit 30 and the sensing unit 100 is connected to each other through a pin connector 20, it is easy to separate and mount for maintenance. At this time, each of the signal processing unit 30 and the sensing unit 100 is connected via a pin connector 20 and a lead wire. The preference processing unit 30 is connected to a communication line for external communication.

On the other hand, the sensor case 10 is composed of a structure capable of separating the case body 11 and the case cover 12 from each other. The case body 11 and the case cover 12 are sealed and coupled through a first o-ring 12a.

First, the signal processing unit 30 is fixed to the hook jaw 11a extending in the inner direction on the inner surface of the case body 11. For example, the signal processing unit 30 may be fastened to the hook jaw 11a by screwing.

Next, the sensing unit 100 is assembled to the lower portion of the case body 11 to directly contact the target structure to be measured.

However, the sensing unit 100 and the case body 11 may be penetrated by foreign substances through a gap present when assembling each other. Accordingly, a second O-ring 40 is inserted between the outer surface of the sensing unit 100 and the inner surface of the case body 11 to prevent foreign matter from entering.

FIG. 2 is a view showing the sensing unit of FIG. 1.

As shown in FIG. 2, the sensing unit 100 senses a change over time of voltage and current in an electrochemical reaction to a target structure S for corrosion detection monitoring.

The sensing unit 100 includes at least one electrolyte region 110 filled with an electrolyte for an electrochemical reaction, a frame 130 for forming the electrolyte region 110, an electrolyte region 110 and a target structure S ), A membrane member 140 for ion exchange, and a frame stopper 150 for fixing the membrane member 140 to the frame 130.

First, each of the electrolyte region parts 110 is filled with a solution containing an electrolyte (for example, K ⁺ , Na ⁺ , Ca ₂ ⁺ , Mg ₂ ⁺ , Cl ^−, etc.), that is, an electrolyte solution, which has the same volume. have. At this time, the electrolyte may be used as long as it simulates a corrosive environment.

In addition, each of the electrolyte region parts 110 is installed with one electrode 120 inserted therein for sensing changes in voltage and current over time.

Here, the electrode 120 is a material having a low reactivity that does not affect an electrical signal (eg, platinum (pt), carbon rod, saturated calomel electrode (SCE), silver / silver chloride Electrodes (Ag-AgCl electrode, etc.) are suitable. One end of the electrode 120 is inserted into the solution of the electrolyte region 110, and a lead wire 121 connected to the pin connector 20 is connected to the other end. At this time, the lead wire 121 is connected to the other end of the electrode 120 by screwing.

Next, the frame 130 is preferably selected from a material having excellent chemical resistance and water resistance (for example, Teflon, epoxy resin, rubber, etc.) so as not to react with the electrolyte solution filled in the electrolyte region 110.

In particular, the frame 130 is made of a structure that opens the lower surface of the electrolyte region 110, and is sealed by the membrane member 140.

Here, the membrane member 140 uses a polymer material having a pore size through which electrolyte ions in the electrolyte solution can move. Polymer materials include polyvinylidene fluoride (PolyVinylidene Fluoride-HexaFluoroPropyl, PVdF-HFP) copolymer, polyvinylidene fluoride, polysulfone, polyether sulfone, polytetra- Fluoroethylene (PolyTera FluoroEthylene, PTFE), polyethylene, polycarbonate, polypropylene, polyvinylalcohol, polyphenylene sulfide, cellulose acetate, Polyamide, polyacrylonitrile, or the like, or a type selected from the group consisting of polyacrylonitrile.

The membrane member 140 does not escape the electrolyte solution, and has a pore size through which electrolyte ions can react with the target structure (S). At this time, when the membrane member 140 is in close contact with the target structure S, electrolyte ions react with the target structure S to generate voltage and current signals. The electrode 120 senses the generated voltage and current signals.

Then, the membrane member 140 is fixed by the frame stopper 150 as described above. The frame stopper 150 may be configured as a pair and assembled into a bolt / nut coupling structure 151.

The frame stopper 150 may be of any shape as long as it is in the form of fixing the membrane member 140, and may be of the same material or different material from the frame 130. The frame stopper 150, like the frame 130, is preferably a material having excellent chemical resistance.

FIG. 3 is a view showing the signal processing unit of FIG. 1, and FIG. 4 is a view showing voltage and current signals measured in the ZRA of FIG. 3.

Referring to FIG. 3, the signal processing unit 30 converts the voltage and current signals sensed through the sensing unit 100 into digital signals and transmits them to the outside.

The signal processing unit 30 includes a ZRA (Zero Resistance Ameter) sensing unit 31, an amplification unit 32, an A / D conversion unit 33, a filter unit 34, and a data communication unit 35.

The ZRA sensing unit 31 may be a resistive ammeter that measures voltage and current signals sensed through the electrode 120.

For example, as illustrated in FIGS. 1 and 2, a description will be given of the case where the electrodes 120 are three electrodes, that is, the first electrode, the second electrode, and the third electrode. In this case, the ZRA sensing unit 31 measures the current signal between the first electrode and the second electrode, or measures the voltage signal between the first electrode and the third electrode. The ZRA sensing unit 31 may measure voltage and current signals as shown in FIG. 4.

The amplification unit 32 amplifies the voltage and current signals measured through the ZRA sensing unit 31, and the A / D conversion unit 33 converts the amplified electrical signal into a digital signal. The filter unit 34 filters the converted digital signal, and the data communication unit 35 transmits the filtered digital signal to the outside (control unit 2 to be described later).

5 is a view showing a corrosion monitoring apparatus using a corrosion monitoring sensor according to an embodiment of the present invention.

5, a corrosion monitoring apparatus using a corrosion monitoring sensor according to an embodiment of the present invention includes a corrosion monitoring sensor 1, a control unit 2, a memory 3, and an output unit 4 .

As described above, the corrosion monitoring sensor 1 measures voltage and current signals through corrosion detection monitoring of the target structure S.

The control unit 2 calculates the noise resistance and corrosion rate in real time from the measured voltage and current signals, and outputs the result through the output unit 4.

Here, the control unit 2 executes computer readable instructions as at least one processor, the memory 3 stores computer readable instructions, and the output unit 4 outputs execution results of computer readable instructions. The control unit 2, the memory 3, and the output unit 4 may be of a configuration included in a computer, a laptop, a smart phone, and the like.

Specifically, the noise resistance Rn is calculated using Equation 1 below using the potential standard deviation (σ _V ) and the current standard deviation (σ _I ).

The noise resistance Rn may be equated to the polarization resistance Rp. The corrosion rate by the general electrochemical tafel measurement method is used as the polarization resistance (Rp) as in Equation 2 below.

Here, β _{ox, M} is the positive-tape constant and β _{red, C} is the negative-tape constant.

Accordingly, the corrosion rate (mm / year) can be expressed by Equation 3 below.

Here, EW (Equivalent Weight) can be represented by ∑f _i M _i / n _i , f _i is the atomic fraction, M _i is the atomic weight, n _i is the valence.

In addition, the control unit 2 calculates a known localization index for checking the corrosion type using the measured voltage and current signals. Through this, the control unit 2 can grasp the type of uniform corrosion or local corrosion. In the case of uniform corrosion, the localization index value is 10 ^-3 , and in the case of local corrosion, it represents a larger value.

The method according to some embodiments may be implemented in the form of program instructions that may be executed through various computer means and may be recorded on a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, or the like alone or in combination. The program instructions recorded on the medium may be specially designed and configured for the present invention, or may be known and available to those skilled in computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks and magnetic tapes, optical media such as CDROMs and DVDs, and magneto-opticals such as floptical disks. And hardware devices specially configured to store and execute program instructions such as magneto-optical media, and ROM, RAM, flash memory, and the like. Examples of program instructions include high-level language code that can be executed by a computer using an interpreter, etc., as well as machine language codes produced by a compiler.

Although the above description has been described with a focus on the novel features of the present invention applied to various embodiments, a person skilled in the art can describe the apparatus and method described above without departing from the scope of the present invention. It will be understood that various deletions, substitutions, and changes are possible in the form and details of the. Accordingly, the scope of the invention is defined by the appended claims rather than in the above description. All modifications within the equivalent scope of the claims are covered by the scope of the present invention.

One ; Corrosion monitoring sensor 2; Control
3; Memory 4; Output
10; Sensor case 11; Case body
12; Case cover 12a: 1st O-ring
20; Pin connector 30; Signal processing unit
31; ZRA sensing unit 32; Amplifier
33; A / D conversion section 34; Filter part
35; Data communication unit 40; Second O-ring
100; Sensing unit 110; Electrolyte area
120; Electrode 121; Lead wire
130; Frame 140; Membrane member
150; Frame stopper S; Target structure

Claims (16)

A sensing unit for sensing changes in voltage and current over time in an electrochemical reaction to a target structure; And
A signal processor for measuring voltage and current signals using the sensing results;
Corrosion monitoring sensor using electrochemical noise, including.
According to claim 1,
The sensing unit,
An electrolyte region part filled with an electrolyte solution for an electrochemical reaction;
An electrode inserted into the electrolyte solution to sense a change in voltage and current over time; And
A membrane member for exchanging electrolyte ions between the electrolyte solution and the target structure;
Corrosion monitoring sensor using electrochemical noise, including.
According to claim 2,
The electrode,
Corrosion monitoring sensor using electrochemical noise, which is any of platinum (pt), carbon rod, saturated calomel electrode (SCE), and silver / silver chloride electrode (Ag-AgCl electrode).
According to claim 2,
The membrane member,
Polyvinylidene fluoride-HexaFluoroPropyl (PVdF-HFP) copolymer, polyvinylidene fluoride, polysulfone, polyether sulfone, polytetra-fluoroethylene (PolyTera FluoroEthylene, PTFE), polyethylene, polycarbonate, polypropylene, polyvinylalcohol, polyphenylene sulfide, cellulose acetate, polyamide ( Polyamide), polyacrylonitrile (polyacrylonitrile) is a type of corrosion monitoring sensor using electrochemical noise, which is used to select one or more from the group consisting of.
According to claim 2,
A frame formed by opening the lower surface of the electrolyte region portion and sealed by the membrane member; And
A frame stopper for fixing the membrane member to the frame;
Corrosion monitoring sensor using an electrochemical noise further comprising a.
The method of claim 5,
The frame,
Corrosion monitoring sensor using electrochemical noise, one of Teflon, epoxy resin, and rubber.
The method of claim 1 or 2,
The sensing unit and the signal processing unit,
Corrosion monitoring sensor using electrochemical noise that is electrically connected to each other through a pin connector.
The method of claim 1 or 2,
A sensor body including a case body for installing the sensing unit on the upper side and a signal body for installing the signal processing unit on the lower side, and a case cover for sealing the case body;
Corrosion monitoring sensor using electrochemical noise that O-ring is inserted between the outer surface of the sensing unit and the inner surface of the case body.
A corrosion monitoring sensor including a sensing unit for sensing voltage and current changes over time in an electrochemical reaction to a target structure and a signal processing unit for measuring a voltage and current signal using the sensing result;
A control unit for calculating noise resistance and corrosion rate from the measured voltage and current signals; And
An output unit for outputting the calculated noise resistance and corrosion rate;
Corrosion monitoring device comprising a.
The method of claim 9,
The control unit,
Corrosion monitoring device that calculates noise resistance by using potential standard deviation and current standard deviation.
The method of claim 10,
The control unit,
Corrosion monitoring device that calculates the corrosion rate by applying the calculated noise resistance to the electrochemical tafel measurement method.
The method of claim 9,
The control unit,
Corrosion monitoring device that checks the type of corrosion by calculating the localization index using the measured voltage and current signals.
The method of claim 9,
The sensing unit,
An electrolyte region part filled with an electrolyte solution for an electrochemical reaction;
An electrode inserted into the electrolyte solution to sense a change in voltage and current over time; And
A membrane member for exchanging electrolyte ions between the electrolyte solution and the target structure;
Corrosion monitoring device comprising a.
The method of claim 13,
A frame formed by opening the lower surface of the electrolyte region portion and sealed by the membrane member; And
A frame stopper for fixing the membrane member to the frame;
Corrosion monitoring device further comprising.
The method of claim 9,
The sensing unit and the signal processing unit,
Corrosion monitoring device that is electrically connected to each other through a pin connector.
The method of claim 9,
The corrosion monitoring sensor,
Includes; a sensor case including a case body for installing the sensing unit on the upper side, and a case body for installing the signal processing unit on the lower side, and a case cover for sealing the case body.
Corrosion monitoring device that the O-ring is inserted between the outer surface of the sensing unit and the inner surface of the case body.

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