CN103822872A - Dew point corrosion monitoring method based on electrochemical noise - Google Patents
Dew point corrosion monitoring method based on electrochemical noise Download PDFInfo
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- CN103822872A CN103822872A CN201310493129.6A CN201310493129A CN103822872A CN 103822872 A CN103822872 A CN 103822872A CN 201310493129 A CN201310493129 A CN 201310493129A CN 103822872 A CN103822872 A CN 103822872A
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Abstract
The invention relates to a dew point corrosion monitoring method based on electrochemical noise, and mainly solves the problem that a dew point corrosion condition cannot be reflected in a real-time manner in the prior art. The method adopts the technical scheme that main components comprising a three-electrode-assembly probe, a zero-resistance ammeter, a high-resistance voltmeter, an A/D convertor and a computer are adopted; the three-electrode-assembly probe comprises a reference electrode assembly and two working electrode assemblies, and the reference electrode assembly is connected with the high-resistance voltmeter; the first working electrode assembly is connected with the zero-resistance ammeter and the high-resistance voltmeter respectively, and the second working electrode assembly is connected with the zero-resistance ammeter; potential noise generated by the high-resistance voltmeter and current noises generated by the zero-resistance ammeter enter the A/D convertor, and the A/D convertor is connected with the computer; the reference electrode assembly comprises at least one reference electrode, the first working electrode assembly comprises at least one working electrode, and the second working electrode assembly comprises at least one working electrode. The technical scheme well solves the problem. The dew point corrosion monitoring method can be used in dew point corrosion monitoring of oil refineries.
Description
Technical field
The present invention relates to a kind of dew point corrosion monitoring method based on electrochemistry noise.
Technical background
At refinery, all there is dew point corrosion problem in heating furnace air preheater and flue, Economizer of Heat Recovery Boiler and pipeline, cylindric heater furnace wall and various overhead condensation cooling system, tank deck gas-liquid phase transition position etc.Existing dew point corrosion monitoring method is mainly to measure dewpoint temperature or weight loss, and the result providing is an indirect parameter or long-time interior average corrosion rate.Actual conditions be temperature when flue gas, aqueous vapor, oil gas in the time that dewpoint temperature is above, substantially can not cause corrosion to equipment; Drop to below critical temperature and work as temperature, in the time that metal surface condensation forms liquid film, corrode, corrosion rate rises rapidly, and existing monitoring method can not reflect dew point corrosion situation in real time.
Electrochemical noise technique has advantages of tested systems undisturbed, can realize continuous monitoring, and can reflect local corrosion information.U.S. Pat Patent5,139,627 have proposed a kind of method and apparatus by electrochemistry noise (EN) technology for detection corrosion.This equipment adopts same material three-electrode system, there is current potential noise (EPN) and current noise (ECN) signal that corrosion reaction produces in potential electrode material, can obtain describing the parameter of corrosion rate and corrosion type by certain computing method in environment.U.S. Pat Patent6,264,824B1 has designed similar measuring system, adopts the method for statistical study in data processing, reflects uniform corrosion and local corrosion condition by the degree of bias and kurtosis, the probability distribution etc. of noise resistance, spot corrosion index, signal.Chinese patent CN101017128A provides a kind of local corrosion analytical approach and device based on electrochemistry noise, and this device adopts four electrode catheters, and noise data is carried out to segmentation statistics and cluster analysis, provides etch state.But their designed electrode systems are all only suitable for continuous electrolysis matter, and inapplicable for discontinuous, the unsettled situation of this liquid film of dew point corrosion.
The atmospheric corrosion galvanic corrosion that belong to thin liquid film under the same as dew point corrosion, the sensor of Corrosion Monitor (ACM) is generally tight staggered dissimilar metal bipolar electrode, in the time having thin liquid film to cover, between electrode, Galvanic Current will be produced, wetting time and corrosiveness of the environment can be reflected by measuring Galvanic Current.But ACM can not provide the even and local corrosion condition of electrode material.
The present invention is based on electrochemistry noise method, solved the monitoring problem of refinery dew point corrosion, especially on-line monitoring problem.
Summary of the invention
Technical matters to be solved by this invention is the problem that can not adopt the dew point corrosion of electrochemistry noise method on-line monitoring refinery in prior art, and a kind of new dew point corrosion monitoring method based on electrochemistry noise is provided.The method is for the dew point corrosion monitoring of refinery, has advantages of simple, harmlessly, can realize real time on-line monitoring, enriched the monitoring means of refining equipment dew point corrosion.
For addressing the above problem, the technical solution used in the present invention is as follows: critical piece comprises three electrode group probes, zero resistance galvanometer, high resistance voltmeter, A/D converter and computing machine, described three electrode group probes comprise a contrast electrode group and two working electrode groups, contrast electrode group is connected with high resistance voltmeter, the first working electrode group respectively with zero resistance galvanometer, high resistance voltmeter is connected, the second working electrode group is connected with zero resistance galvanometer, the current potential noise that high resistance voltmeter produces, the current noise that zero resistance galvanometer produces enters A/D converter, A/D converter is connected with computing machine, described contrast electrode group comprises at least one contrast electrode, described the first working electrode group comprises at least one working electrode, described the second working electrode group comprises at least one working electrode, described the first working electrode and the second working electrode, working electrode and contrast electrode are and are staggered, do not contact mutually.
In technique scheme, described three electrode group probes are made up of compact arranged same material electrode, and material is selected the material identical or close with position that equipment is surveyed; The described suitable position that three electrode groups probes is placed in to equipment under test and easily occurs dew point corrosion, when gas is during at three electrode group detecting head surface condensation and dewfalls, zero resistance galvanometer shows electric current and produces.The current potential noise signal of high resistance voltmeter and zero resistance galvanometer collection is inputted computing machine through A/D converter, judge by related software whether current signal is zero, in the time that electric current is zero, illustrates and occur without dew point corrosion, in the time that electric current is non-vanishing, automatically record current potential and current signal, and calculate corrosion parameter according to formula; Described dew point corrosion monitoring can be carried out by real-time online; The voltage of described high resistance voltmeter at least 1 megohm; Described contrast electrode group comprises a contrast electrode, and described the first working electrode group comprises a working electrode, and described the second working electrode group comprises a working electrode; Folder lining heat insulating lamella between described adjacent electrode.
While using device of the present invention, probe is placed in to equipment under test and easily occurs the suitable position of dew point corrosion, when flue gas is during at detecting head surface condensation and dewfall, between electrode group, covered and conducting by liquid film, zero resistance galvanometer shows electric current and produces.The current noise signal of the current potential noise signal of high resistance voltmeter collection and zero resistance galvanometer collection is inputted computing machine through A/D converter, judge by software whether current signal is zero, in the time that electric current is zero, illustrates and occur without dew point corrosion, record is without the period of dew point corrosion, in the time that electric current is non-vanishing, automatically record current potential and current signal, and calculate the corrosion parameter such as the degree of bias and kurtosis of noise resistance, spot corrosion index, current potential and current signal, can reflect even and local corrosion condition.A kind of dew point corrosion monitoring method based on electrochemistry noise is provided.It can improve and integrate prior art, compact arranged same material three electrode groups are designed, electrochemical noise technique is applied to the monitoring of refining equipment dew point corrosion, synchro measure current potential and current noise signal, calculate the even and local corrosion parameter while there is dew point corrosion.Device of the present invention can be measured actual condition and divide into period and the corrosion condition of the raw dew point corrosion of preparation, have advantages of simple, harmless, can realize real time on-line monitoring, enrich the monitoring means of refining equipment dew point corrosion, obtain good technique effect.
Below by embodiment, the invention will be further elaborated, but be not limited only to the present embodiment.
Embodiment
[embodiment 1]
Dew point corrosion electrochemistry noise monitoring device of the present invention is made up of three electrode group probes, high resistance voltmeter, zero resistance galvanometer, A/D converter and computing machine and corresponding software can on-line monitoring.Three electrode group probes are made up of compact arranged same material electrode, and material is selected the material identical or close with position that equipment is surveyed, to truly reflect equipment corrosion situation.Material is made to the little cube electrode of long 20 millimeters, wide 2 millimeters, folder lining heat insulating lamella between adjacent electrode, approximately 0.2 millimeter of spacing, arrange (wherein W1 is that the first working electrode, W2 are that the second working electrode, R are contrast electrode) according to the order of W1W2RW1W2RW1W2, use resistant to elevated temperatures epoxy encapsulation.These electrodes connect and are aggregated into three groups with wire, respectively as contrast electrode, the first working electrode and the second working electrode.
While using device of the present invention, probe is placed in to equipment under test and easily occurs the suitable position of dew point corrosion, when flue gas is during at detecting head surface condensation and dewfall, between electrode group R, W1 and W2, covered and conducting by liquid film, zero resistance galvanometer shows electric current and produces.Current noise signal between W1 and the W2 of the current potential noise signal between R and the W1 of high resistance voltmeter collection and zero resistance galvanometer collection is inputted computing machine through A/D converter 4, judge by software whether current signal is zero, in the time that electric current is zero, illustrates and occur without dew point corrosion, record is without the period of dew point corrosion, in the time that electric current is non-vanishing, automatically record current potential and current signal, and calculate noise resistance Rn according to formula, spot corrosion index LI, the degree of bias Sk of current potential and current signal and kurtosis Ku, wherein utilize Rn and coordinate other parameters can reflect uniform corrosion rate, LI, the Changing Pattern of Sk and Ku can be used to reflect local corrosion tendency.Sample frequency is set as 2Hz, calculates one group of corrosion parameter every 1024 seconds (approximately 17 minutes),
Above-mentioned several electrochemistry noise parameter is all the result based on current potential current signal being carried out to statistical study.
Wherein noise resistance Rn:
σ E and σ I are the standard deviation of current potential or current signal.Conventionally Rn and uniform corrosion rate are inverse ratio, and approach with polarization resistance Rp.
Spot corrosion index LI:
σ I is the standard deviation of current signal, RMS
ifor the root mean square of current signal.It is generally acknowledged, LI approaches at 1 o'clock, shows the generation of local corrosion; LI approaches 0 and means that electrode surface occurs uniform corrosion or keeps passive state.
Degree of bias Sk:
Xi is actual measurement current potential or current value,
for mean value, σ is the standard deviation of current potential or electric current, and n is sampling number.The degree of bias has been described the symmetry of noise data distributional pattern, and the degree of bias=0 o'clock distributional pattern is about average symmetry.The noise signal degree of bias of uniform corrosion approaches 0.
Kurtosis Ku:
Xi is actual measurement current potential or current value,
for mean value, σ is the standard deviation of current potential or electric current, and n is sampling number.Kurtosis has been described the steep slow degree of noise data distributional pattern, and kurtosis=3 o'clock distributional pattern is identical with the steep slow degree of normal distribution.The noise signal kurtosis of uniform corrosion approaches 3.
Obviously, adopt method of the present invention, can reach the object that adopts the dew point corrosion of electrochemistry noise method on-line monitoring refinery, there is larger technical advantage, can be used in the monitoring of refinery dew point corrosion.
Claims (7)
1. the dew point corrosion monitoring method based on electrochemistry noise, critical piece comprises three electrode group probes, zero resistance galvanometer, high resistance voltmeter, A/D converter and computing machine, described three electrode group probes comprise a contrast electrode group and two working electrode groups, contrast electrode group is connected with high resistance voltmeter, the first working electrode group respectively with zero resistance galvanometer, high resistance voltmeter is connected, the second working electrode group is connected with zero resistance galvanometer, the current potential noise that high resistance voltmeter produces, the current noise that zero resistance galvanometer produces enters A/D converter, A/D converter is connected with computing machine, described contrast electrode group comprises at least one contrast electrode, described the first working electrode group comprises at least one working electrode, described the second working electrode group comprises at least one working electrode, described the first working electrode and the second working electrode, working electrode and contrast electrode are and are staggered, do not contact mutually.
2. the dew point corrosion monitoring method based on electrochemistry noise according to claim 1, is characterized in that described three electrode groups probes are made up of compact arranged same material electrode, and material is selected the material identical or close with position that equipment is surveyed.
3. the dew point corrosion monitoring method based on electrochemistry noise according to claim 1, it is characterized in that the described suitable position that three electrode groups probes is placed in to equipment under test and easily occurs dew point corrosion, when gas is during at three electrode group detecting head surface condensation and dewfalls, zero resistance galvanometer shows electric current and produces.The current potential noise signal of high resistance voltmeter and zero resistance galvanometer collection is inputted computing machine through A/D converter, judge by related software whether current signal is zero, in the time that electric current is zero, illustrates and occur without dew point corrosion, in the time that electric current is non-vanishing, automatically record current potential and current signal, and calculate corrosion parameter according to formula.
4. the dew point corrosion monitoring method based on electrochemistry noise according to claim 1, is characterized in that described dew point corrosion monitoring can carry out by real-time online.
5. the dew point corrosion monitoring method based on electrochemistry noise according to claim 1, is characterized in that the voltage of described high resistance voltmeter at least 1 megohm.
6. the dew point corrosion monitoring method based on electrochemistry noise according to claim 1, it is characterized in that described contrast electrode group comprises a contrast electrode, described the first working electrode group comprises a working electrode, and described the second working electrode group comprises a working electrode.
7. the dew point corrosion monitoring method based on electrochemistry noise according to claim 1, is characterized in that folder lining heat insulating lamella between described adjacent electrode.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104502267A (en) * | 2014-12-31 | 2015-04-08 | 天津大学 | Electrochemical noise corrosion type distinguishing method based on support vector machine |
| CN104502265A (en) * | 2014-12-31 | 2015-04-08 | 天津大学 | Electrochemical noise testing method under normal temperature and normal pressure |
| CN108061704A (en) * | 2017-12-06 | 2018-05-22 | 中国石油大学(华东) | A kind of single electrode crossed array wire beam electrode system corroded under Test coverage object |
| CN109033446A (en) * | 2018-08-20 | 2018-12-18 | 中石化（洛阳）科技有限公司 | Corrosion type method of discrimination and device |
| CN112782256A (en) * | 2019-11-06 | 2021-05-11 | 中国石油化工股份有限公司 | Multi-parameter probe for corrosion monitoring and corrosion detection system |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5139627A (en) * | 1986-05-12 | 1992-08-18 | Capcis Limited | Corrosion monitoring |
| JPH09159601A (en) * | 1995-12-08 | 1997-06-20 | Babcock Hitachi Kk | Method and apparatus for predicting corrosion of metallic material |
| US6264824B1 (en) * | 1998-02-20 | 2001-07-24 | Integriti Investments Ltd. | Assessment of corrosion |
| CN2750317Y (en) * | 2004-12-09 | 2006-01-04 | 中国船舶重工集团公司第七二五研究所 | Multi-channel galvanic corrosion experiment data collecting device |
| JP2006258602A (en) * | 2005-03-17 | 2006-09-28 | Ebara Corp | Probe for monitoring dew point corrosion |
| CN101017128A (en) * | 2006-10-13 | 2007-08-15 | 华中科技大学 | Analysis method for localized corroding based on electrochemistry noise |
| CN102132162A (en) * | 2008-07-02 | 2011-07-20 | 倍加福公司 | Electrochemical noise as a localized corrosion indicator |
| CN102507430A (en) * | 2011-11-11 | 2012-06-20 | 天津亿利科能源科技发展股份有限公司 | Online monitoring device for corrosion in pipeline |
| CN102692438A (en) * | 2012-06-15 | 2012-09-26 | 哈尔滨工程大学 | Dew point corrosion experiment device capable of realizing electrochemical tests |
-
2013
- 2013-10-18 CN CN201310493129.6A patent/CN103822872B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5139627A (en) * | 1986-05-12 | 1992-08-18 | Capcis Limited | Corrosion monitoring |
| JPH09159601A (en) * | 1995-12-08 | 1997-06-20 | Babcock Hitachi Kk | Method and apparatus for predicting corrosion of metallic material |
| US6264824B1 (en) * | 1998-02-20 | 2001-07-24 | Integriti Investments Ltd. | Assessment of corrosion |
| CN2750317Y (en) * | 2004-12-09 | 2006-01-04 | 中国船舶重工集团公司第七二五研究所 | Multi-channel galvanic corrosion experiment data collecting device |
| JP2006258602A (en) * | 2005-03-17 | 2006-09-28 | Ebara Corp | Probe for monitoring dew point corrosion |
| CN101017128A (en) * | 2006-10-13 | 2007-08-15 | 华中科技大学 | Analysis method for localized corroding based on electrochemistry noise |
| CN102132162A (en) * | 2008-07-02 | 2011-07-20 | 倍加福公司 | Electrochemical noise as a localized corrosion indicator |
| CN102507430A (en) * | 2011-11-11 | 2012-06-20 | 天津亿利科能源科技发展股份有限公司 | Online monitoring device for corrosion in pipeline |
| CN102692438A (en) * | 2012-06-15 | 2012-09-26 | 哈尔滨工程大学 | Dew point corrosion experiment device capable of realizing electrochemical tests |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104502267A (en) * | 2014-12-31 | 2015-04-08 | 天津大学 | Electrochemical noise corrosion type distinguishing method based on support vector machine |
| CN104502265A (en) * | 2014-12-31 | 2015-04-08 | 天津大学 | Electrochemical noise testing method under normal temperature and normal pressure |
| CN108061704A (en) * | 2017-12-06 | 2018-05-22 | 中国石油大学(华东) | A kind of single electrode crossed array wire beam electrode system corroded under Test coverage object |
| CN109033446A (en) * | 2018-08-20 | 2018-12-18 | 中石化（洛阳）科技有限公司 | Corrosion type method of discrimination and device |
| CN112782256A (en) * | 2019-11-06 | 2021-05-11 | 中国石油化工股份有限公司 | Multi-parameter probe for corrosion monitoring and corrosion detection system |
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