JP2014038026A - Deposited salt measurement method and deposited salt collection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deposited salt measurement method and a deposited salt collection device capable of easily collecting salt deposited on the surface of metal structure in an optionally specified area and capable of precisely measuring the amount of deposited salt of 1 μg/mor more.SOLUTION: Using the deposited salt collection device, deposited salt of 1 μg/mor more deposited on the surface of a metal structure in an optionally specified area is dissolved into a collection solution. The amount of the deposited salt per unit area is easily and precisely measured based on the concentration of the deposited salt contained in the collection solution.

Description

The present invention dissolves the salt attached to the surface of a target object in a recovery liquid at an arbitrarily defined area for accurate measurement of the amount of attached salt, which is a corrosive factor for metals in the atmosphere, and recovers the recovered salt. A method for measuring the amount of adhering salt per unit area from a concentration of adhering salt in a liquid simply and with high accuracy, and an adhering salt content recovery tool.

In recent years, metal materials used outdoors such as bridges, building structural materials, and transportation bodies for trains and automobiles are increasing. However, metal corrosion in the atmospheric environment is a problem. Metal materials that cause local corrosion, such as stainless steel, can cause significant losses in a short period of time. Therefore, it is important to investigate the corrosiveness of metal materials in actual use environments, predict the life of metal materials, select the optimal steel type, and take measures for surface treatment such as painting.

The corrosive factors of the main metals in the atmosphere are the amount of sea salt particles flying in the air (hereinafter referred to as the amount of flying sea salt particles) and the wetting time. Based on the results of analysis and investigation of these corrosive factors in the actual usage environment, it is possible to predict the lifetime of the metal material (Non-patent Document 1).

Methods for measuring the amount of flying sea salt particles include the dry gauze method (JIS Z2381 General Rules for Outdoor Exposure Test Method Reference 3) and the wet candle method (ISO 9225). However, these measurement methods are strongly influenced by weather factors such as wind speed, wind direction, and topography, and topographic factors. The problem is that the amount of incoming sea salt particles is different. Outside the coastal area, there are problems such as low correlation between the amount of incoming sea salt particles measured by the above method and the corrosion rate of the metal material.

Therefore, since the flying sea salt particles that actually adhere to the surface of the metal material are directly involved in the corrosion of the metallic material outdoors, the flying sea salt that has adhered to the predetermined area of the actual metallic material exposed to the outdoors for a certain period of time. It is necessary to collect salt particles and measure the amount of incoming sea salt particles from the composition analysis.

In recent years, corrosion sensors using galvanic pairs have been developed and used for measuring and monitoring corrosive factors in the atmospheric environment. Among them, the ACM (Atmospheric Corrosion Monitor) type corrosion sensor developed by Yodogawa et al. Has reported that it can measure the wet time and the amount of sea salt attached, and has a high correlation with the corrosion rate of metal materials (Non-patent Document 1) ) The amount of sea salt attached to the sensor is currently analyzed based on a calibration curve created from the corrosion current output of the sensor to which a predetermined amount of seawater has been artificially attached and the amount of sea salt attached. However, since air pollutants other than sea salt affect the corrosion rate, a calibration curve is created from the amount of salt that actually adheres to the sensor surface outdoors and the corrosion current output of the sensor, and the sea salt of the corrosive factor There is a social demand for technology to monitor the amount of adhesion with high accuracy.

Masa Shinohara et al .: Zairyo-to-Kankyo, 55, 495 (2006)

As a method for recovering the attached salt on the metal surface, there is a method of wiping the surface of the metal structure with clean gauze. However, on the metal surface where the rust layer is formed thick, salt remains in the rust layer, and the entire amount cannot be recovered. In addition, the method of collecting the adhered salt content of the metal structure with ultrasonic waves in a water bath is limited in the shape and size of the metal structure depending on the size of the ultrasonic bath. It is impossible to collect the attached salt. Salinity may be volatilized from the collected liquid into the air by long-term ultrasonic waves.

The amount of adhering salt is the amount of adhering salt per unit area obtained by dividing the quantitative value of the recovered salinity by the recovery area, and accurate measurement of the recovery area is important in order to obtain a highly accurate measurement value. However, when the shape of the metal structure is complicated or has irregularities, the surface area cannot be measured accurately. Therefore, it is conceivable to recover the surface salinity in a limited area. The method for limiting the recovery area may be masking other than the recovery part using an adhesive seal, but there is contamination due to the elution of ionic components from the adhesive and the seal.

Accordingly, an object of the present invention is to provide a method for measuring the amount of adhering salt on the surface of the metal structure which can be easily collected in an arbitrarily defined area and can measure the amount of adhering salt of 1 μg / m ² or more with high accuracy. And providing an attached salt content recovery tool. Because it is possible to collect the attached salt content that has come and adhered in the actual usage environment, it is possible to investigate the exact correlation between the corrosion rate of the metal material and the attached salt content or the corrosive environmental factors, and it is possible to predict the life. .

As a result of diligent research to solve the above problems, the present inventor easily and accurately collects the adhering salt content on the surface of the metal structure in an arbitrarily defined area with the following contents. The present inventors have found that this can be done and have come to achieve the present invention. The recovered liquid is brought into contact with the measurement surface of the target object to which the salt that is a corrosive factor of the metal adheres, and 1 μg / m ² or more of the adhered salt adhered to the surface of the target object is dissolved in the recovered liquid, and the recovered liquid is adhered. A method for measuring the amount of adhering salt, characterized by measuring the salinity concentration and calculating the amount of adhering salt per unit area.

In the invention according to claim 2, the recovery liquid is set in a sealed state and brought into contact with a measurement area partitioned into a predetermined area of the measurement surface, and ultrasonic vibration is performed in a state where the recovery liquid is in contact with the measurement area. Is added for 3 minutes or more.

  In the invention according to claim 3, the recovery liquid is set in a sealed state and brought into contact with the measurement area partitioned into a predetermined area of the measurement surface, and the recovery liquid is held in contact with the measurement area. The method for measuring an attached salt content according to claim 1.

In the invention according to claim 4, the impregnated member impregnated with the recovering liquid is brought into close contact with the measurement region partitioned into a predetermined area of the measurement surface for 1 minute or more, and the recovered impregnated member is washed. It is characterized by measuring the concentration of adhering salt.

The invention according to claim 5 is the method for measuring an attached salt content according to any one of claims 1 to 4, wherein the recovered liquid is pure water.

6. The method according to claim 6, wherein the target object is a sensor that detects a corrosion state due to a metal structure or adhering salt. .

The invention according to claim 7 is characterized in that a wetted part that is fixed to a measurement surface of a target object to which a salt that is a corrosive factor of metal adheres to partition a measurement region, and the wetted part and the target object are watertight. The attached salt content recovery tool comprising: a presser portion fixed to the liquid contact portion, wherein the recovered liquid is stored in the liquid contact portion to dissolve the salt content.

The invention according to claim 8 includes a wetted part that is fixed to a measurement surface of a target object to which a salt content that is a corrosive factor of a metal adheres to partition a measurement region, and an impregnation part that soaks and holds the recovered liquid. And a pressing unit that is attached to the impregnated part and is inserted into the liquid contact part to bring the impregnated part into close contact with the target object.

The method for measuring the amount of adhering salt and the adhering salt content recovery jig of the present invention simply recovers the adhering salt content of 1 μg / m ² or more adhering to the surface of the metal structure in an arbitrarily defined area, and adheres per unit area. The amount of salt can be measured with high accuracy. Therefore, the time for measuring the amount of adhering salt is reduced and the cost is reduced. Moreover, it becomes possible to measure the kind and amount of salt adhering in a certain period in an actual environment where the metal structure is used. Since an ultra trace amount of 1 μg / m ² or more can be measured, the period for depositing salt in an actual environment can be shortened. Therefore, it is possible to predict the life of the metal structure in the intended use environment from the reported relationship between the amount of deposited salt and the corrosion rate of the metal material, which contributes greatly to the selection of the optimum metal material and the minimization of the life cycle cost. To do.

Schematic configuration diagram for attached salt content recovery tool according to the present invention Schematic configuration diagram of another attached salt recovery tool according to the present invention Graph showing the relationship between ultrasonic time and chloride ion and sulfate ion concentration changes in the recovered solution

In FIG. 1, it is a schematic block diagram regarding the adhesion salt content recovery jig | tool of this embodiment. The attached salt content recovery jig includes a liquid contact part 2 that partitions a measurement area 4 having a predetermined area with respect to the surface of the metal structure 1 that is a target object for recovering the attached salt content, and the metal structure 1 and the liquid contact part 2. Is provided with a plate-like presser portion 3 that is watertightly fixed.

The liquid contact portion 2 is made of a cylindrical acrylic resin material, and is formed so that an end surface that comes into contact with the surface of the metal structure 1 is in close contact with the surface of the metal structure 1 in a watertight manner. The cross-sectional shape of the wetted part 2 is set to a predetermined area in which the cross-sectional area of the internal space becomes the measurement region 4. Area of the measurement region 4 may be appropriately set depending on the object to be measured ^may be set to 1 cm 2 to 50 cm ^2. The material of the wetted part 2 is not particularly limited as long as the same component as the adhering salt does not elute into the recovered liquid, and materials such as resin, metal, glass, and ceramics can be used. For example, an acrylic resin is preferable. Further, the shape of the liquid contact part 2 may be a shape other than a cylindrical shape as long as it can hold the recovered liquid. For example, it may be a rectangular tube having a polygonal cross-sectional shape.

In order to fix the wetted part 2 and the metal structure 1, the presser part 3 includes a pair of presser plates 30 and a fastener 31, and holds the metal structure 1 and the wetted part 2 so as to sandwich the pressed part 3. The plate 30 is arranged and fixed by fasteners 31 attached to the four corners of the presser plate 30. The liquid contact part 2 is formed with an opening 5 for introducing the recovered liquid into the liquid contact part 2. And each fastener 31 is clamp | tightened equally and the liquid-contacting part 2 is set to the state which press-contacted to the metal structure 1 watertightly. The presser plate 30 may be made of the same material as the liquid contact part 2, and the fastener 31 may be attached at two or more locations, for example, a metal wing screw and nut may be used.

Next, a measurement method using the attached salt content recovery jig shown in FIG. 1 will be described. First, the metal structure 1 is placed on one presser plate 30, and the liquid contact part 2 is disposed on the surface of the metal structure 1. Then, the other presser plate 30 is arranged on the upper surface of the liquid contact part 2, and the presser plates 30 are connected to each other by the fasteners 31 and fastened and fixed. Thus, the measurement area 4 having a predetermined area is defined and set on the surface of the metal structure 1 by bringing the liquid contact portion 2 into close contact with the metal structure 1.

Next, a predetermined amount of the collected liquid is introduced from the opening 5, and the adhering salt on the surface of the metal structure 1 is dissolved in the collected liquid. The amount of the recovered liquid may be an amount required for concentration measurement, and specifically, an amount of 1 ml to 100 ml is preferable. Further, the recovered liquid may be any liquid that can dissolve the adhering salt, and pure water, an organic solvent such as ethanol, or a mixed solution thereof is used. In particular, it is preferable to use pure water, and as pure water, one having a specific resistance of 18.3 MΩ · cm or more that does not contain impurities is more preferable.

When adhering salt is dissolved in the recovered liquid, the adhering salt is uniformly dissolved in the recovered liquid. Therefore, you may make it accelerate | stimulate melt | dissolution by applying ultrasonic vibration to an attached salt content recovery jig | tool. When applying ultrasonic vibration to the attached salt content collecting tool, the ultrasonic vibrator may be operated in a state where the attached salt content collecting tool is immersed in an ultrasonic bath to apply vibration. The operation time is preferably set to 3 minutes or longer, and if it is shorter than 3 minutes, dissolution may be insufficient depending on the type of salt. Further, the attached salt content recovery tool may be swung so as to promote the dissolution so that the recovered liquid is stirred.

After the adhering salt is dissolved in the recovered liquid, the concentration is measured by putting the recovered liquid into the concentration measuring device from the adhering salt recovering tool. Concentration measurement can be performed by a qualitative quantitative analysis method for each ion component contained in the recovered liquid. Examples of the qualitative quantitative analysis method include a titration method, a colorimetric method, and a separation analysis method. A separation analysis method using ion chromatography with a suppressor is preferable for measuring the concentration of a trace amount of ion components of 1 mg / L or less.

The amount of adhering salt contained in the recovered liquid is calculated from the adhering salt concentration obtained by concentration measurement. Then, the amount of adhering salt per unit area can be calculated from the area of the measurement region 4 divided by the wetted part 2 and the obtained amount of adhering salt.

Examples of the target object for measuring the concentration of the attached salt content include sensors such as an ACM sensor that measures the degree of corrosion due to the attached salt content in addition to the above-described metal structure. In the case of a metal structure, a structure such as a part using a metal material which is installed outdoors and may corrode due to adhering salt is a target. Examples of the attached salt that is a corrosive factor for metals include sea salt or salts containing water-soluble ions of components derived from air pollutants. Examples of water-soluble ions include chloride ions, nitrate ions, nitrite ions, sulfuric acid. Examples of the ions include water-soluble ions, fluorine ions, sodium ions, potassium ions, ammonium ions, magnesium ions, calcium ions, and NOx and SOx ions. Moreover, the salt containing water-soluble corrosive ion, such as organic acid and hypochlorous acid, is also mentioned.

Sensors such as ACM sensors have a galvanic pair and measure corrosive factors in the atmospheric environment from the corrosion current value to monitor the corrosion state. However, the amount of salt actually attached to the measurement surface is As a result, it is possible to quantitatively analyze the correlation between the measurement data from the sensor and the amount of the attached salt, based on the actual attached salt, and to monitor the corrosion state with higher accuracy. .

FIG. 2 is a schematic configuration diagram regarding another attached salt content recovery tool. In this example, the cylindrical wetted part 6 is disposed on the surface of the metal structure 1 as in the example shown in FIG. 1, but a magnet or the like is attached to the end surface of the wetted part 6 that contacts the metal structure 1. It is fixed to the surface by magnetic force. By fixing the wetted part 5 to the surface of the metal structure 1, the measurement region 7 is defined as in the example shown in FIG. Inside the wetted part 6, a pressing part 9 having an impregnated part 8 impregnated with the collected liquid attached to the tip part is slidably inserted. The pressing portion 9 is formed in a cylindrical shape, and an impregnation portion 8 is attached to one end portion and sealed. The impregnation part 8 is made of a flexible impregnation member capable of soaking the recovered liquid, and is formed in a size that is in sliding contact with the inner peripheral surface of the liquid contact part 6 in close contact therewith. As such an impregnated member, a porous material such as a sponge, a material that can be impregnated with a recovered liquid such as a nonwoven fabric, a woven fabric, and a knitted fabric may be used, and the porous material such as a sponge can be uniformly adhered to the entire surface of the measurement region. Therefore, it is preferable.

Next, a measurement method using the attached salt recovery jig shown in FIG. 2 will be described. First, the wetted part 6 is disposed on the surface of the metal structure 1 and fixed by magnetic force, and a measurement area 7 having a predetermined area is defined and set on the surface of the metal structure 1. Next, a predetermined amount of the collected liquid is stored in another container, and the impregnated portion 8 is immersed in the stored collected liquid so that the impregnated portion 8 is sufficiently impregnated with the collected liquid. Then, with the recovered liquid infiltrated into the impregnation portion 8, the pressing portion 9 is inserted into the liquid contact portion 6 to bring the impregnation portion 8 into close contact with the entire measurement region 7. After the impregnation part 8 is brought into close contact with the measurement region 7 for 1 minute or more, the pressing part 9 is pulled out from the liquid contact part 6 and the impregnation part 8 is immersed in the collected liquid in another container. The recovered liquid is sufficiently stirred while the impregnated part 8 is immersed, and the adhering salt content recovered in the impregnated part 8 is dissolved in the recovered liquid.

Next, as in the case of the attached salt content recovery tool shown in FIG. 1, the amount of attached salt content per unit area is calculated by measuring the attached salt concentration of the recovered solution in which the attached salt content is dissolved.

In addition, after making the impregnation part 8 contact | adhere to the measurement area | region 7, the collection | recovery liquid is thrown into the press part 9, and it stirs, the adhesion salt content of the measurement area | region 7 is dissolved in a collection liquid, and adhesion salt content density | concentration is measured. You can also.

The following examples illustrate the invention in detail.

(Example 1) Plate-like metal structure (SUS420J2, length 50 mm × width 50 mm × thickness 1 mm) Seven specimens were exposed to the outdoors from June 1 to 0.5 to 40 days, changing the number of days. did. These were used as test pieces of this example.

The attached salt content on the surface of the test piece was collected using the attached salt content collecting jig shown in FIG. The area of the measurement region 4 was set to 15 cm ² , the fastener 31 was made of a metal thumb screw and nut, and the other parts were made of acrylic resin. The wetted part 2 and the pressing part 30 were washed with ultrapure water and dried in advance in order to prevent analysis contamination.

Next, a test piece showing a recovery procedure using the attached salt content collecting jig was attached to the attached salt content collecting jig, and 20 ml of the collected solution was put into the wetted part 2. In order to prevent the recovered liquid from leaking from the opening 5, the lower part of the attached salt content recovery tool and the metal structure 1 are placed in an ultrasonic bath set at 40 ° C. and subjected to ultrasonic vibration for 3 minutes. I took it out. Then, a part of the recovered liquid was collected and subjected to quantitative analysis of chloride ions and water-soluble ions using a suppressor ion chromatography (manufactured by Nippon Dionex). The amount of adhered salt (mg / m 2; hereinafter referred to as “Ws”) was calculated based on the obtained adhered salt concentration and the area of the measurement region. The total chloride ion was converted to NaCl and used as the amount of attached salt. The results are shown in Table 1.

(Example 2) Using the attached salt content recovery tool shown in FIG. 2, the amount of attached salt content of test pieces 2 and 5 in Table 1 was measured. The area of the measurement region 6 was set to 15 cm ² , a resin sponge was used for the impregnation part 8, and the liquid contact part 6 was fixed with a magnet. The wetted part 6, the impregnated part 8 and the pressing part 9 were washed with ultrapure water and dried in advance in order to prevent analysis contamination. First, the impregnation part 8 is soaked with 1 ml of the recovered liquid. After the wetted part 6 is brought into close contact with the test piece by magnetic force, the pressing part 9 is inserted into the wetted part 6 to bring the impregnated part 8 into close contact with the measurement region 7 and 19 ml of the recovered liquid is put into the pressed part 9. did. Put a stirring mixer rod into the pressing part and stir at low speed to dissolve the adhering salt. Thereafter, a part of the collected liquid was collected, and the chloride ion concentration was quantitatively analyzed by ion chromatography in the same manner as in Example 1. The calculation result of Ws is shown in Table 1.

(Comparative Example 1)
About the test piece 2 of Table 1, the surface other than the area | region of the same shape and the same area as the measurement area | region 4 of the attached salt content recovery tool of FIG. 1 was coat | covered with water-resistant adhesive tape, and the surface similar to the measurement area | region 4 was exposed. Set. The test piece covered with the adhesive tape was dipped in a beaker containing 100 mL of ultrapure water, placed in an ultrasonic bath at 40 ° C. for 3 minutes, and then removed from the ultrasonic bath. Then, a part of ultrapure water in the beaker was collected, and quantitative analysis of chloride ions and water-soluble ions was performed by ion chromatography with a suppressor in the same manner as in Example 1. Table 1 shows the calculation result of Ws.

In the test pieces 1 to 7, with the increase in the number of exposure days, the attached salt content increases and Ws also increases. The test piece 1 had a low chloride ion concentration in the recovered liquid, which was the limit of quantification, and Ws could not be measured. This was considered that the outdoor exposure period was as short as half a day, and the attached salt content was less than 1 μg / m ² . On the other hand, test pieces 2 to 7 having Ws of 1 μg / m ² or more were measurable in Example 1. In Comparative Example 1, since the recovered liquid entered between the test piece and the adhesive tape during immersion in the ultrasonic bath, and the surface other than the measurement region could not be completely masked, Ws of the test piece of Example 1 More than 10 times. Further, elution of nitrate ions and nitrite ions from the adhesive was confirmed in the recovered liquid, and depending on the type of water-resistant adhesive tape, it is considered that there is a possibility of adversely affecting the quantitative analysis of the adhered salt. In Example 2, the same amount of Ws as in Example 1 could be measured in test pieces 2 and 5.

(Example 3) NaCl adhesion amount is 0.1 μg / m ^{2 to} 1000 mg / m ^{2 on the} sensor central part (surface area 11 cm ² ) which is a comb-shaped electrode part of an ACM sensor (iron-silver type; manufactured by Shrinks Co., Ltd.). After the artificial seawater diluted to a predetermined amount of was attached in the form of water droplets, it was dried in an oven at 60 ° C.

About the test piece (Nos. 1-8, 3 pieces each) of the ACM sensor to which NaCl was adhered, in the same manner as in Example 1, the collected salt content and the quantitative analysis of chloride ions in the recovered solution were performed. The analysis value was an average value of three test pieces to which the same amount was adhered. All chloride ions were converted as NaCl. Table 2 shows the results of the NaCl adhesion amount, analytical value (Ws), and recovery rate (Ws / NaCl adhesion amount x 100%) adhered to each sensor.

(Comparative example 2) About the test pieces 1-8 of Table 2, similarly to the comparative example 1, surfaces other than the measurement area of Example 3 and the same shape same area were coat | covered with the water-resistant adhesive tape. The exposed surface was wiped once with gauze moistened with ultrapure water. Next, the gauze was immersed in 20 mL of ultrapure water, and quantitative analysis of chloride ions was performed by ion chromatography with a suppressor. Table 2 shows the amount of adhering salt Ws in which all chloride ions are converted to NaCl.

In Example 3, Ws was recovered at 97% or more in test pieces 3 to 8 in which NaCl of 0.001 mg / m ² or more was artificially attached. It is thought that all the artificially attached amount was recovered. In test piece 1, the chloride ion concentration in the recovered liquid was the limit of quantification of ion chromatography analysis, and both Example 2 and Comparative Example 2 were not detectable. Specimen 2 could be quantitatively analyzed for the chloride ion concentration, but the recovery rate was 40% in Example 3 and 20% in Comparative Example 2, which was as low as 20%. In Comparative Example 2, the recovery rate was 97% for the test piece 8 with the NaCl adhesion amount of 1000 mg / m ² or more, but the recovery rate of the other test pieces was low.

(Example 4) Four types of ACM sensors (iron-silver, iron-carbon, aluminum-silver, zinc-silver; manufactured by Shrinks Co., Ltd.) at the same outdoor location for 30 days from December 1st As a result, the salt particles in the atmosphere naturally adhered. Since the ACM sensor is a self-corrosion type, after the test, corrosion products such as iron rust, zinc oxide, and aluminum oxide were generated on the sensor surface. These samples were used as test pieces 1 to 4 in the same manner as in Example 3, and the attached salt content recovery tool of FIG. 1 was attached to the comb-shaped electrode portion of each sensor, and the collected salt content was collected and measured. Show.

(Comparative Example 3) The test piece 1 shown in Table 3 was tested in the same manner as in Comparative Example 2. The amount of adhering salt Ws is shown in Table 3.

Since the exposure test was conducted at the same point and period, the amount of salt attached to all the test pieces was the same. From the results of Table 3, in this example, the measurement difference depending on the sensor type was within ± 6%. It was confirmed that the amount of adhering salt from all four types of sensors could be collected and the amount of adhering salinity could be measured even in a test piece with surface irregularities such as a rust layer and a portion limited to the comb-shaped electrode portion of the sensor. Comparative Example 3 is a test piece formed with a rust layer exposed outdoors for 30 days. The recovery rate of Ws = 68 mg / m ² of Example 3 of test piece 1 is as low as about 59%, and the total amount of adhered salt can be recovered. It did not come.

(Example 5) For two specimens of test piece 1 of ACM sensor to which flying sea salt particles were naturally attached by outdoor exposure for 10 days and test piece 6 of Table 2, the same as in Example 3, the collected salt content recovery of FIG. Wearing tools. After putting this in an ultrasonic bath for 0 seconds, 10 seconds, 30 seconds, 1 minute, 2, 3, 5, 6 minutes, chloride ions and sulfate ions in the recovered solution were subjected to ion chromatography with a suppressor. Quantitative analysis was performed. FIG. 3 shows changes in the concentration of chloride ions and sulfate ions with respect to the time in the ultrasonic bath.

From FIG. 3, the chloride ion of the test piece 1 became constant in the ultrasonic bath for 1 minute or more, and the sulfate ion became constant in 3 minutes or more. In the test piece 6, both ions became constant after 30 seconds. The test piece 1 had a rust layer on the surface of the portion to be collected due to actual exposure, and more time was needed to recover the adhering salt than the test piece 6.

Example 6 Using the attached salt content recovery tool shown in FIG. 2, the amount of attached salt content at three places on the painted metal wall surface of a structure installed outdoors was measured. First, the impregnation part 8 is soaked with 5 mL of the recovered liquid. Then, after the wetted part 5 is brought into close contact with a magnetic force, the pressing part 9 is inserted into the wetted part 6 and the impregnated part 8 is pressed against the coated metal wall surface for 60 seconds. Thereafter, the pressing portion 9 was gently pulled out, the sponge of the impregnation portion 8 was washed with 10 mL of ultrapure water, and the chloride ion concentration of the washing water was quantitatively analyzed by ion chromatography. Table 4 shows the results of Ws.

Example 7 A test piece (length 50 mm × width 50 mm × thickness 1 mm) was cut out from the coated metal wall surface used in Example 6. In the same manner as in Example 1, the collected salt content, its measurement and calculation were performed on the surface on the outside air side of the obtained test piece. Table 4 shows the results of Ws.

In Example 6 and Example 7, almost the same amount of attached salt was recovered and measured from the same metal structure. The recovery method as in Example 6 is effective in that the attached salt content can be easily recovered outdoors without cutting the structure.

DESCRIPTION OF SYMBOLS 1 Metal structure 2 Liquid contact part 3 Holding part 4 Measurement area | region 5 Opening 6 Liquid contact part 7 Measurement area 8 Impregnation part 9 Press part

Claims (8)

The recovered liquid is brought into contact with the measurement surface of the target object to which the salt that is a corrosive factor of the metal adheres, and 1 μg / m ² or more of the adhered salt adhered to the surface of the target object is dissolved in the recovered liquid, and the recovered liquid is adhered. A method for measuring the amount of adhering salt, characterized by measuring the salinity concentration and calculating the amount of adhering salt per unit area.   The recovery liquid is set in a sealed state and brought into contact with a measurement area partitioned into a predetermined area on the measurement surface, and ultrasonic vibration is applied for 3 minutes or more in a state where the recovery liquid is in contact with the measurement area. The attached salt content measuring method according to claim 1.   The recovery liquid is set in a sealed state and brought into contact with a measurement area partitioned into a predetermined area on the measurement surface, and the recovery liquid is held in contact with the measurement area. Of measuring the amount of adhering salt.   Impregnating the impregnated member impregnated with the collected liquid for one minute or more to the measurement area partitioned into a predetermined area on the measurement surface, and measuring the adhering salt concentration of the recovered liquid after washing the impregnated member adhered The attached salt content measuring method according to claim 1, characterized in that: The method for measuring an attached salt content according to any one of claims 1 to 4, wherein the recovered liquid is pure water. The attached salt content measuring method according to claim 1, wherein the target object is a metal structure or a sensor that detects a corrosion state due to attached salt content. A wetted part that is fixed to a measurement surface of a target object to which a salt that is a corrosive factor of the metal is attached and partitions a measurement region; and a presser that fixes the wetted part and the target object in a watertight manner, An attached salt content recovery tool, wherein the recovered liquid is stored in the liquid contact part to dissolve the salt content. A wetted part that is fixed to a measurement surface of a target object to which a salt that becomes a corrosive factor of metal adheres and partitions a measurement region, an impregnated part that soaks and holds the recovered liquid, and the impregnated part are attached. An attached salt content recovery tool, comprising: a pressing portion that is inserted into the liquid contact portion and causes the impregnation portion to be in close contact with the target object.