CN109030326B - Method for measuring low-temperature corrosion resistance and corrosion rate of condensing heat exchanger - Google Patents
Method for measuring low-temperature corrosion resistance and corrosion rate of condensing heat exchanger Download PDFInfo
- Publication number
- CN109030326B CN109030326B CN201810725700.5A CN201810725700A CN109030326B CN 109030326 B CN109030326 B CN 109030326B CN 201810725700 A CN201810725700 A CN 201810725700A CN 109030326 B CN109030326 B CN 109030326B
- Authority
- CN
- China
- Prior art keywords
- heat exchanger
- condensate
- measuring
- corrosion
- wall surface
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 238000005260 corrosion Methods 0.000 title claims abstract description 85
- 230000007797 corrosion Effects 0.000 title claims abstract description 83
- 238000000034 method Methods 0.000 title claims abstract description 47
- 239000002253 acid Substances 0.000 claims abstract description 25
- 238000012360 testing method Methods 0.000 claims abstract description 22
- 229910052751 metal Inorganic materials 0.000 claims abstract description 12
- 239000002184 metal Substances 0.000 claims abstract description 11
- 238000009616 inductively coupled plasma Methods 0.000 claims abstract description 5
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 37
- 239000003546 flue gas Substances 0.000 claims description 37
- 238000009833 condensation Methods 0.000 claims description 26
- 230000005494 condensation Effects 0.000 claims description 26
- 239000000243 solution Substances 0.000 claims description 15
- 239000003929 acidic solution Substances 0.000 claims description 8
- 230000007935 neutral effect Effects 0.000 claims description 4
- 239000000463 material Substances 0.000 abstract description 13
- 238000005259 measurement Methods 0.000 abstract description 9
- 230000008569 process Effects 0.000 abstract description 6
- 238000004088 simulation Methods 0.000 abstract description 6
- 238000010998 test method Methods 0.000 abstract description 6
- 238000002791 soaking Methods 0.000 abstract description 5
- 238000012795 verification Methods 0.000 abstract description 5
- 238000004364 calculation method Methods 0.000 abstract description 3
- 238000011156 evaluation Methods 0.000 abstract description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 30
- CSDREXVUYHZDNP-UHFFFAOYSA-N alumanylidynesilicon Chemical compound [Al].[Si] CSDREXVUYHZDNP-UHFFFAOYSA-N 0.000 description 7
- 238000002485 combustion reaction Methods 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 150000002500 ions Chemical class 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 3
- 229910052593 corundum Inorganic materials 0.000 description 3
- 238000006056 electrooxidation reaction Methods 0.000 description 3
- 229910001845 yogo sapphire Inorganic materials 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- -1 hydrogen ions Chemical class 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 239000002918 waste heat Substances 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 229910021502 aluminium hydroxide Inorganic materials 0.000 description 1
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002848 electrochemical method Methods 0.000 description 1
- 238000003487 electrochemical reaction Methods 0.000 description 1
- 239000008151 electrolyte solution Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 229910001679 gibbsite Inorganic materials 0.000 description 1
- XLYOFNOQVPJJNP-ZSJDYOACSA-N heavy water Substances [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 description 1
- 238000013178 mathematical model Methods 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000012266 salt solution Substances 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000000779 smoke Substances 0.000 description 1
- 238000010183 spectrum analysis Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N17/00—Investigating resistance of materials to the weather, to corrosion, or to light
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Biodiversity & Conservation Biology (AREA)
- Ecology (AREA)
- Environmental & Geological Engineering (AREA)
- Environmental Sciences (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Testing Resistance To Weather, Investigating Materials By Mechanical Methods (AREA)
Abstract
本发明公开了一种测量冷凝式换热器低温防腐能力和腐蚀速率的方法，其中低温防腐能力的测量方法包括以下步骤：步骤一、收集换热器内排出的冷凝液；步骤二、测量该冷凝液的pH值。针对腐蚀速率的测量方法，包括以下步骤：步骤一、测试单位时间内收集的冷凝液量；步骤二、采用电感耦合等离子体质谱仪对冷凝液中的酸成分及金属成分含量进行测量，再对该换热器冷凝部分换热面积进行统计计算；步骤三、将上述参数代入公式，计算腐蚀速率。采用该方法测量参数简单，过程容易操作，评价指标客观，可有效解决了实验测试、材料浸泡、模拟验证等测试方法中存在的工作量大，测量难度高的问题。
The invention discloses a method for measuring the low-temperature anti-corrosion ability and corrosion rate of a condensing heat exchanger, wherein the method for measuring the low-temperature anti-corrosion ability comprises the following steps: step 1, collecting the condensate discharged from the heat exchanger; step 2, measuring the pH of the condensate. The method for measuring the corrosion rate includes the following steps: step 1, testing the amount of condensate collected in a unit time; step 2, using an inductively coupled plasma mass spectrometer to measure the content of acid components and metal components in the condensate, and then measure the content of the condensate. Statistical calculation is performed on the heat exchange area of the condensing part of the heat exchanger; in step 3, the above parameters are substituted into the formula to calculate the corrosion rate. Using this method to measure parameters is simple, the process is easy to operate, and the evaluation index is objective, which can effectively solve the problems of large workload and high measurement difficulty in test methods such as experimental testing, material soaking, and simulation verification.
Description
Technical Field
The invention relates to a method for predicting low-temperature corrosion resistance and corrosion rate of flue gas in a condensing heat exchanger, in particular to a method for predicting low-temperature corrosion resistance and corrosion rate of flue gas in the condensing heat exchanger.
Background
The condensing heat exchanger is used as a high-efficiency heat exchange device and is widely applied to devices such as a gas water heater, an industrial boiler, an economizer, an air preheater and the like. The flue gas formed by fuel combustion contains water vapor and SOXAnd NOx and other acid gases, when the temperature of the heat exchange wall surface is lower than the condensation temperature of the acid gases, the water vapor and the acid steam can be combined to generate acid condensate which is attached to the heat exchange wall surface of the heat exchanger, and the wall surface of the heat exchanger is corroded. On the one hand, the heat exchange performance of the heat exchanger is influenced, and in severe cases, the use safety and the service life of the heat exchanger are damaged. Under the technical background of the global vigorous development of high-efficiency heat exchangers and the utilization of low-temperature flue gas waste heat, the influence caused by the low-temperature corrosion is more prominent and sharp by deeply utilizing the flue gas waste heat.
At present, a research method aiming at the low-temperature corrosion capacity and the corrosion speed of the flue gas mainly comprises experimental tests, material soaking, simulation verification and the like. The experimental test method has the most real test effect, but the experimental process has a long period, the experimental operation is complex, and particularly, the measurement of the corrosion degree and the area of the heat exchange wall surface of the closed heat exchanger is difficult to implement. Although the test material soaking method is convenient to operate, the difference between the corrosion occurrence condition and the actual working condition of the heat exchanger is far, and the error between the experimental test result and the actual condition is large. The simulation verification test method can well control the factors of corrosion occurrence, such as the composition of acid steam in the flue gas, the temperature and the flow rate of the flue gas, the temperature change of the heat exchange wall surface and the like, and influence on the heat exchange wall surface of the heat exchanger. However, the cases of researching low-temperature corrosion by adopting a simulation test method are few, and the corrosion principle of the factors on the heat exchange wall surface mostly utilizes an empirical formula, so that the actual test precision requirement cannot be met. Therefore, in the research process of the low-temperature corrosion phenomenon of the condensing heat exchanger, a method capable of accurately measuring and predicting the condensing corrosion capacity and rate of the low-temperature flue gas is needed.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a method for predicting the low-temperature corrosion capacity and the corrosion rate of flue gas in a condensing heat exchanger, and the method can be used for judging the strength of the corrosion capacity when the low-temperature corrosion phenomenon in the condensing heat exchanger occurs by measuring the pH value of condensate; the low-temperature corrosion rate in the heat exchanger can also be measured according to the generation amount and the property of the condensate in unit time.
In order to achieve the purpose, the invention adopts the technical scheme that:
the invention relates to a method for measuring low-temperature corrosion resistance and corrosion rate of a condensing heat exchanger, which comprises a method for measuring the low-temperature corrosion resistance of the heat exchanger and a method for measuring the corrosion rate of the heat exchanger;
the method for measuring the low-temperature corrosion resistance of the heat exchanger comprises the following steps:
collecting condensate discharged from the interior of the heat exchanger, and then testing the pH value of the condensate, wherein if the condensate is an acidic solution and the pH value is larger or the solution is a neutral solution, the corrosion phenomenon on the wall surface of the heat exchanger is serious; if the condensate is an acidic solution and the pH value is small, the corrosion phenomenon of the wall surface of the heat exchanger is light;
the method for measuring the corrosion rate of the heat exchanger comprises the following steps:
(1) testing the amount of condensate discharged from the condensing section of the heat exchanger in unit time;
(2) measuring the contents of acid components and metal components in the condensate collected in unit time by using an inductively coupled plasma mass spectrometer, wherein the measured amount of the metal components is the same as the amount of the metal corroded on the wall surface of the heat exchanger; meanwhile, the heat exchange area of the part of the heat exchanger where the flue gas condensation phenomenon occurs is counted and calculated;
(3) the corrosion rate of the heat exchanger was calculated using the following formula:
wherein N isfThe corrosion rate of the wall surface of the condensation part of the heat exchanger is expressed in mol/(s.m)2) (ii) a V is the volume of condensate collected per unit time in m3(ii) a C is the mass concentration of corrosive elements in the collected condensate and has the unit of g/m3(ii) a A is the area of the wall surface of the heat exchanger with the occurrence of the condensation phenomenon in the heat exchanger, and the unit is m2(ii) a t is the collection time length in units of s; m is the molar mass of the element to be corroded and has the unit of g/mol.
The method has the beneficial effects that: the method has the advantages of simple parameters to be measured, easy operation of the measurement process and objective evaluation indexes. The method effectively solves the problems of large workload and high measurement difficulty in test methods such as experimental test, material soaking, simulation verification and the like.
Drawings
FIG. 1 is a graph of the relationship between low temperature corrosion protection and corrosion protection rate versus heat transfer wall temperature;
fig. 2 is a schematic diagram of the condensation phenomenon on the wall surface of the heat exchanger.
Detailed Description
The invention is described in detail below with reference to the figures and specific embodiments.
As can be seen from fig. 1, the corrosion rate of the heat exchanger wall surface is related to the heat exchange wall surface temperature, and is inversely related to the pH value of the condensed water. For the current natural gas, wherein H2The S content is about 8ppm, the condensation temperature of the flue gas is related to the excess air coefficient of combustion and the combustion condition under the normal combustion condition, and when the excess air coefficient is 1.0, the dew point temperature of the flue gas formed after combustion is 57 ℃. When the temperature of the wall surface is higher than the value, the water vapor in the flue gas does not condense, condensed water adhesion cannot be formed on the wall surface, and the low-temperature corrosion phenomenon of the wall surface cannot be caused. When the temperature is lower than the condensation temperature [ t ] along with the decrease of the wall temperature]When the process is carried out, water vapor in the flue gas begins to condense and absorbs acid vapor in the flue gas to form acid solution. Due to the condensation of the water vapor, the water vapor pressure in the flue gas is reduced, the dissolution amount of the acid vapor in the flue gas is small, and the pH value of the solution formed at the moment is high. Along with the reduction of the temperature of the heat exchange wall surface, the condensation rate of the water vapor is accelerated, the amount of condensed water is increased, and the pH value of the condensed water is reduced. When the water vapor condenses to the saturated vapor pressure at this pressure, the corrosion rate of the heat exchange wall surface reaches a local maximum, and the pH of the condensed water also reaches a local minimum. When the wall temperature further decreases, the amount of condensed water increases, the partial pressure of the water vapor decreases, and the partial pressure of the acid gas increases, so that the amount of dissolved acid gas does not increase, and the pH of the condensed liquid reaches a local maximum. As the temperature of the wall surface is continuously reduced to the dew point temperature of the acid steam, a large amount of acid steam begins to be condensed, a large amount of condensed acid solution is added in the condensed water besides the partially dissolved acid ions, and the pH value of the condensed water is also sharply reduced.
Under the normal working condition of the condensing heat exchanger, the condensed water discharged from the interior of the heat exchanger is collected, the pH value of the condensed solution is obtained through testing, and the value can be used for representing the index of the low-temperature corrosion resistance of the heat exchanger. When the pH value is larger and is close to a value of 7, the pH value of the condensate discharged from the heat exchanger is larger by indicating that the acid solution component in the condensate discharged from the internal condensation section of the heat exchanger is less and the neutral salt solution component is more, which further deduces that the acid solution of the part has stronger electrochemical corrosion reaction on the wall surface material of the heat exchanger, and a large amount of acid solution reacts with metal elements in the wall surface material of the heat exchanger. Similarly, when the pH value of the condensate obtained by the test is small, it indicates that the condensed acid solution does not have a violent electrochemical method in the condensation section inside the heat exchanger and the metal material of the heat exchanger, so that a large amount of acidic ions can be discharged out of the heat exchanger and enter the test sample. Therefore, the low-temperature corrosion resistance of the condensing heat exchanger can be well represented by testing the collected condensate.
Based on the principle, the method for measuring the low-temperature corrosion resistance and the corrosion rate of the condensing heat exchanger comprises a heat exchanger low-temperature corrosion resistance measuring method and a heat exchanger corrosion rate measuring method;
the method for measuring the low-temperature corrosion resistance of the heat exchanger comprises the following steps:
collecting condensate discharged from the interior of the heat exchanger, and then testing the pH value of the condensate, wherein if the condensate is an acidic solution and the pH value is larger or the solution is a neutral solution, the corrosion phenomenon on the wall surface of the heat exchanger is serious, and the pH value is generally between 5 and 7; if the condensate is an acidic solution and the pH value is small, the corrosion phenomenon of the wall surface of the heat exchanger is light, and the pH value is generally between 3 and 5;
if the corrosion phenomenon of the wall surface of the heat exchanger is serious, the hydrogen ions in the condensate liquid are subjected to chemical reaction on the wall surface of the heat exchanger, so that the content of the hydrogen ions in the liquid discharged out of the heat exchanger is reduced, and the pH value of the collected condensate liquid is also high; if the wall surface of the heat exchanger has no corrosion phenomenon, the acid condensate generated by condensation in the condensate can be directly discharged out of the heat exchanger, and the pH value of the collected condensate is smaller. Through the analysis, the pH value of the condensate can be tested, and the pH value obtained through the test is used as an index for judging the low-temperature corrosion resistance of the condensing heat exchanger.
The method for measuring the corrosion rate of the heat exchanger comprises the following steps:
(1) testing the amount of condensate discharged from the condensing section of the heat exchanger in unit time;
(2) and measuring the contents of acid components and metal components in the condensate collected in unit time by using an inductively coupled plasma mass spectrometer (ICP-MS), wherein the measured amount of the metal components is the same as the amount of the metal corroded on the wall surface of the heat exchanger. Meanwhile, the heat exchange area of the part of the heat exchanger where the flue gas condensation phenomenon occurs is counted and calculated, and direct measurement solving can be adopted, wherein the area of the heat exchange flat wall surface can be directly obtained by solving the product of the length and the width of the corrosion surface, the area of the fin part can be obtained by solving the area of the outer surface of the cylinder, and finally the heat exchange area of the whole condensation part is obtained by adding. If a relevant mathematical model exists for the heat exchanger, the condensation heat exchange area can be directly adopted for calculation. Both methods are prior art.
(3) The corrosion rate of the heat exchanger was calculated using the following formula:
wherein N isfThe corrosion rate of the wall surface of the condensation part of the heat exchanger is expressed in mol/(s.m)2) (ii) a V is the volume of condensate collected per unit time in m3(ii) a C is the mass concentration of corrosive elements in the collected condensate and has the unit of g/m3(ii) a A is the area of the wall surface of the heat exchanger with the occurrence of the condensation phenomenon in the heat exchanger, and the unit is m2(ii) a t is the collection time length in units of s; m is the molar mass of the element to be corroded and has the unit of g/mol.
Example 1
The material of the condensing heat exchanger is cast silicon aluminum alloy, and after spectral analysis, the material of the cast silicon aluminum heat exchanger is known to contain 87.21% of Al, 11.7% of Si and other elements such as Fe, Cu, Mn and the like.
Flue gas flowWhen passing through the heat exchange wall surface of the heat exchanger, the temperature is TfThe flue gas exchanges heat with the fins and the heat exchange wall surface, a temperature boundary layer is formed at the fins of the heat exchange wall surface, and when the flue gas is contacted with the wall surface, the temperature of the flue gas is reduced to be the same as that of the wall surface, namely, the temperature is t1And around the wall, the temperature of the flue gas gradually rises until a maximum value t2. At this time, assume the temperature t1Greater than the condensation temperature of the flue gas [ t]That is, the temperature of the surface of the fins is higher than the dew point temperature of the flue gas, so that the water vapor in the flue gas cannot be condensed, and no condensed water is generated. But with the temperature T of the cold waterwDecrease of t1Will also decrease with time if the temperature t1Is less than the dew point temperature of the flue gas [ t ]]A temperature zone is formed on the surface of the fins, in which the temperature of the fin surface is less than the dew point temperature t]The specific area can be seen in the area of the condensation water membrane in fig. 1. At this time, the water vapor in the flue gas will be condensed in this area, which can be defined as "flue gas condensation area". Can find t1The smaller the value, the larger the area of the "flue gas condensation zone" is, the more amount of condensed water is generated. While at the same time the temperature TwThe water enters the heat exchanger from the direction opposite to the flowing direction of the flue gas for heat exchange.
The water film formed in the smoke condensation area contains a large amount of acidic solution, the pH value of the acidic solution is less than 7, the cast silicon-aluminum heat exchanger material contains a plurality of elements, the active characteristics of the elements are different, so that the Al element in the heat exchanger material is an anode, other elements are cathodes, and an infinite number of tiny electrochemical corrosion loops are formed between the Al element and the other elements due to close contact between the Al element and the other elements. The electrochemical corrosion loop mainly comprises a cathode, an anode, an electrolyte solution and an external loop. The specific chemical reactions that occur are as follows:
Al-3e-→Al3+
O2(g)+2H2O+4e-→4OH-(aq)
Al3++3OH-→Al(OH)3
2Al(OH)3→Al2O3+3H2O
al ions in the wall material of the cast-silicon-aluminum heat exchanger are oxidized into Al due to electrochemical reaction3+Ion, and O dissolved in water2And H2O, after taking an electron, forms OH-Ions of which OH-Al with ions on the wall of the heat exchanger3+After the ionic reaction, Al (OH) is formed on the wall surface of the heat exchanger3. Then the Al (OH)3Will be oxidized again to Al2O3And H2O, wherein Al2O3A dense oxide film is formed on the wall of the heat exchanger to prevent further corrosion of the acid solution.
The method for measuring the low-temperature corrosion resistance of the heat exchanger by adopting the method comprises the following steps of:
(1) the condensate discharged from the inside of the heat exchanger was collected and then the pH of the condensate was tested.
(2) If the pH value of the condensate is between 5 and 7, judging that the low-temperature corrosion capacity of the flue gas in the condensing heat exchanger is stronger at the moment, and also judging that the low-temperature corrosion resistance of the wall surface of the condensing heat exchanger is weaker at the moment; if the pH value of the condensate is 3-5, the low-temperature corrosion capacity of the flue gas in the condensing heat exchanger is judged to be weaker, and the low-temperature corrosion resistance of the wall surface of the condensing heat exchanger is also judged to be stronger.
The pH value of the condensate of the cast silicon-aluminum condensing heat exchanger obtained by the method and the steps is 4, which shows that the low-temperature corrosion capability of the flue gas in the cast silicon-aluminum condensing heat exchanger is weaker, and the low-temperature corrosion resistance of the wall surface is stronger.
After the experimental test is finished, the equipment is disassembled and checked, and the phenomena of corrosion pits, spots and the like do not appear on the heat exchange fins and the wall surface in the heat exchanger, so that the heat exchanger made of the material has strong low-temperature corrosion capability, and the reliability of the low-temperature corrosion resistance capability measuring method is verified.
The method for measuring the corrosion rate of the heat exchanger comprises the following steps:
(1) testing the amount of condensate discharged from the condensing section of the heat exchanger in unit time;
(2) the contents of the acid component and the metal component in the condensate collected per unit time were measured using an inductively coupled plasma mass spectrometer (ICP-MS).
(3) And counting the heat exchange area of the part of the internal flue gas condensation phenomenon of the heat exchanger.
(4) The corrosion rate of the heat exchanger is calculated by adopting the following formula:
by adopting the method and the steps, the cast silicon-aluminum condensing heat exchanger in the embodiment is tested to obtain the following components: v is 0.03m3H; c is 11.8g/m3(ii) a A is 2.1m2(ii) a t is 1 hour, 3600 s; m is Al and the molar mass is 27 g/mol. The corrosion rate N of the cast silicon-aluminum heat exchanger is obtained by a calculation formulafIs 1.7X 10-6mol/(s·m2)。
Through specific operation of the embodiment, the method is found that measurement parameters are simple and easy to realize, the measurement process is simple and easy to master, and the evaluation index is objective in measurement of low-temperature corrosion resistance and corrosion resistance rate. The method effectively solves the problems of large workload and high measurement difficulty in test methods such as experimental test, material soaking, simulation verification and the like.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that are within the spirit of the present invention are intended to be included therein.
Claims (1)
1. A method for measuring low-temperature corrosion resistance and corrosion rate of a condensing heat exchanger is characterized by comprising the following steps: the method comprises a method for measuring the low-temperature corrosion resistance of the heat exchanger and a method for measuring the corrosion rate of the heat exchanger;
the method for measuring the low-temperature corrosion resistance of the heat exchanger comprises the following steps:
collecting condensate discharged from the interior of the heat exchanger, and then testing the pH value of the condensate, wherein if the condensate is an acidic solution and the pH value is larger or the solution is a neutral solution, the corrosion phenomenon on the wall surface of the heat exchanger is serious; if the condensate is an acidic solution and the pH value is small, the corrosion phenomenon of the wall surface of the heat exchanger is light;
the method for measuring the corrosion rate of the heat exchanger comprises the following steps:
(1) testing the amount of condensate discharged from the condensing section of the heat exchanger in unit time;
(2) measuring the contents of acid components and metal components in the condensate collected in unit time by using an inductively coupled plasma mass spectrometer, wherein the measured amount of the metal components is the same as the amount of the metal corroded on the wall surface of the heat exchanger; meanwhile, the heat exchange area of the part of the heat exchanger where the flue gas condensation phenomenon occurs is counted and calculated;
(3) the corrosion rate of the heat exchanger was calculated using the following formula:
wherein N isfThe corrosion rate of the wall surface of the condensation part of the heat exchanger is expressed in mol/(s.m)2) (ii) a V is the volume of condensate collected per unit time in m3(ii) a C is the mass concentration of corrosive elements in the collected condensate and has the unit of g/m3(ii) a A is the area of the wall surface of the heat exchanger with the occurrence of the condensation phenomenon in the heat exchanger, and the unit is m2(ii) a t is the collection time length in units of s; m is the molar mass of the element to be corroded and has the unit of g/mol.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810725700.5A CN109030326B (en) | 2018-07-04 | 2018-07-04 | Method for measuring low-temperature corrosion resistance and corrosion rate of condensing heat exchanger |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810725700.5A CN109030326B (en) | 2018-07-04 | 2018-07-04 | Method for measuring low-temperature corrosion resistance and corrosion rate of condensing heat exchanger |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109030326A CN109030326A (en) | 2018-12-18 |
| CN109030326B true CN109030326B (en) | 2021-03-16 |
Family
ID=65522370
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810725700.5A Expired - Fee Related CN109030326B (en) | 2018-07-04 | 2018-07-04 | Method for measuring low-temperature corrosion resistance and corrosion rate of condensing heat exchanger |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109030326B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114970291B (en) * | 2022-07-28 | 2022-12-06 | 中国电器科学研究院股份有限公司 | Air conditioner heat exchanger atmospheric corrosion prediction method based on finite element simulation technology |
| CN116359119B (en) * | 2023-03-27 | 2023-10-13 | 浙江大学 | Pipeline corrosion prevention test system based on thermoelectric chemical battery waste heat utilization and control method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009144952A (en) * | 2007-12-13 | 2009-07-02 | Kurita Water Ind Ltd | Steam monitoring device |
| JP2016061678A (en) * | 2014-09-18 | 2016-04-25 | 新日鐵住金株式会社 | Corrosion resistance test device and corrosion resistance test method |
| CN106290042A (en) * | 2015-05-29 | 2017-01-04 | 武汉大学 | A kind of method that quick research aluminum corrodes in demineralized water |
| CN106958830A (en) * | 2017-05-09 | 2017-07-18 | 中国大唐集团科学技术研究院有限公司华东分公司 | One kind collects aqueous and treatment for reuse system and method for discharging fume |
| CN106986828A (en) * | 2016-11-13 | 2017-07-28 | 滨州学院 | A kind of utilization soybean oil prepares the method and its compounding metal inhibitor of Imidazoline Quatemary-ammonium-salt Corrosion Inhibitor |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8906202B2 (en) * | 2007-07-24 | 2014-12-09 | Nalco Company | Method of detecting and reducing contamination in papermaking boiler systems |
-
2018
- 2018-07-04 CN CN201810725700.5A patent/CN109030326B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009144952A (en) * | 2007-12-13 | 2009-07-02 | Kurita Water Ind Ltd | Steam monitoring device |
| JP2016061678A (en) * | 2014-09-18 | 2016-04-25 | 新日鐵住金株式会社 | Corrosion resistance test device and corrosion resistance test method |
| CN106290042A (en) * | 2015-05-29 | 2017-01-04 | 武汉大学 | A kind of method that quick research aluminum corrodes in demineralized water |
| CN106986828A (en) * | 2016-11-13 | 2017-07-28 | 滨州学院 | A kind of utilization soybean oil prepares the method and its compounding metal inhibitor of Imidazoline Quatemary-ammonium-salt Corrosion Inhibitor |
| CN106958830A (en) * | 2017-05-09 | 2017-07-18 | 中国大唐集团科学技术研究院有限公司华东分公司 | One kind collects aqueous and treatment for reuse system and method for discharging fume |
Non-Patent Citations (3)
| Title |
|---|
| Performance of casting aluminum-silicon alloy condensing heating exchanger for gas-fired boiler;Weixue Cao et al.;《Heat and Mass Transfer》;20180129;第54卷;第1958-1959页，4 .4 Comparison of three water heaters * |
| 冷凝式燃气热水器换热器低温段防腐试验研究;郑永新等;《煤气与热力》;20070731;第27卷(第7期);35-41 * |
| 褐煤弱氧化改质脱水水质对比分析;王小华等;《煤炭工程》;20161231;第48卷(第11期);115-119 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109030326A (en) | 2018-12-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1590981B (en) | Method for manufacturing heat exchanger tube corrosion monitoring sensor | |
| CN109030326B (en) | Method for measuring low-temperature corrosion resistance and corrosion rate of condensing heat exchanger | |
| CN105277482B (en) | A kind of distilling apparatus overhead system dew point corrosion test method | |
| CN101738365A (en) | Accelerated test method for simulating atmospheric corrosion of metal materials | |
| Levy et al. | Recovery of water from boiler flue gas using condensing heat exchangers | |
| Carranza et al. | Effect of fluoride ions on crevice corrosion and passive behavior of alloy 22 in hot chloride solutions | |
| CN112394024B (en) | A rapid evaluation method for the performance of weathering steel rust layer for transmission towers in coastal atmospheric environment | |
| CN109376858A (en) | Method for predicting performance of condensing heat exchanger based on partial load rate | |
| Cao et al. | Performance of casting aluminum-silicon alloy condensing heating exchanger for gas-fired boiler | |
| CN101334346B (en) | Ingredient content analytical method for turbine blade salt deposition and scaling | |
| CN110332911A (en) | Using the measurement method of steam condenser vacuum measurement heat exchanging pipe fouling thickness | |
| CN113340800A (en) | Corrosion resistance test method for carbon steel | |
| CN111413458A (en) | Method for detecting nitrogen content in steelmaking auxiliary material | |
| CN109522586B (en) | Method for optimizing fin structure of heat exchanger based on field synergy theory | |
| CN117686418A (en) | Coupling probe, method and system for detecting instant and accumulated corrosion rate | |
| Yang et al. | Evaluation of Corrosion Inhibitors in Cooling Water Systems Using a Coupled Multi-Electrode Array Sensor | |
| Solberg et al. | Corrosion of Unstressed Steel Specimens and Various Alloys by High-Temperature Steam | |
| CN1560617A (en) | Evaluation method of scaling and antiscaling performance | |
| Hajduk | Research of deposit accumulated on heat exchange surfaces in the light of thermal degradation of heat exchange aparatus of steam power plants part I: study of real sediments | |
| JP2004239638A (en) | Method and apparatus for determining corrosiveness in water | |
| CN109900625B (en) | Method for evaluating service life of solar energy absorption film for heat collector in composite corrosion environment | |
| CN111426727B (en) | Method for estimating pH value of desulfurization wastewater after direct contact heat exchange with raw flue gas | |
| CN117907562B (en) | A method for simultaneously detecting the content of multiple elements in a coating | |
| Kreso et al. | A Study of the Vapor-and Particle-Phase Sulfur Species in the Heavy-Duty Diesel Engine EGR Cooler | |
| Hindin et al. | Materials Performance for Residential High Efficiency Condensing Furnaces |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20210316 Termination date: 20210704 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |