JP2020139957A - Chelate agent quantification system - Google Patents

Abstract

To provide a chelate agent quantification method and a chelate agent quantification system capable of easily measuring existence of a chelate agent in solution and quantifying the chelate agent in the solution.SOLUTION: A chelate agent quantification method comprises the processes to: form solution by first submerging a measurement object which undergoes a chelate treatment in water and then removing incineration ash; add a predetermined amount of metal ions to the solution; and quantify a chelate agent in the solution on the basis of a measurement of turbidity of the solution with metal ions added thereto. Through these processes, the chelate agent quantification method can easily measure existence of the chelate agent in the solution depending on presence/absence of a metal complex occurred in the solution and quantify the chelate agent in the solution based on the measurement of turbidity in the solution.SELECTED DRAWING: Figure 2

Description

The present invention relates to a chelating agent quantification method and a chelating agent quantification system.

Residues generated when incinerating industrial waste and the like and incineration ash of exhaust gas (particularly fly ash in exhaust gas) may contain heavy metals. Heavy metals contained in such incineration ash need to be detoxified for environmental protection. Examples of the detoxification treatment include a method of solidifying with cement or the like (solidification treatment), a method of insolubilizing heavy metals using an organic polymer-based chelating agent (insolubilization treatment), and the like. When performing the insolubilization treatment, it is common to add an excess chelating agent to the incineration ash in order to ensure that the heavy metal is insolubilized by the Ministry of the Environment Notification No. 13 test. However, since the above-mentioned chelating agent is difficult to decompose naturally and is expensive, a method for easily obtaining an appropriate amount of the chelating agent to be added to the incineration ash in the above-mentioned insolubilization treatment has been proposed.

For example, in Patent Document 1 below, in order to obtain the amount of chelating agent required for the insolubilization treatment of heavy metals, the eluate in which water mixed with incineration ash is eluted is colored with metal ions such as a copper nitrate solution. A method of adding a solution as a reagent is described. In this method, the presence or absence of an excess chelating agent (that is, a chelating agent that has not reacted with heavy metals) in the eluate is determined by the presence or absence of coloring of the mixed solution when the reagent is added to the eluate.

Japanese Unexamined Patent Publication No. 2004-216209

In the case of the method described in Patent Document 1, since the determination is made only by the presence or absence of coloring of the mixed solution, the presence or absence of an excess chelating agent can be easily determined, but the amount of the excess chelating agent cannot be determined. Can not.

The present invention has been made to solve such a problem, and a chelating agent quantification method and a chelating agent quantification system capable of easily measuring the presence or absence of a chelating agent in a solution and quantifying the chelating agent in a solution. The purpose is to provide.

The method for quantifying a chelating agent according to the present invention includes a step of forming a solution by mixing a chelated object to be measured with water and then removing the object to be measured, and a predetermined amount of metal ions in the solution. And a step of quantifying the chelating agent in the solution based on the measurement of the turbidity of the solution to which the metal ion is added.

According to the method for quantifying a chelating agent according to the present invention, the turbidity of a solution to which a predetermined amount of metal ions is added is measured. When the chelating agent used when the object to be measured is chelated remains in the solution, the solution is suspended by the reaction between the remaining chelating agent and the metal ion, so that the chelating agent in the solution can be easily prepared. The presence or absence of Further, as the concentration of the remaining chelating agent increases, the turbidity of the solution to which the metal ion is added increases. Therefore, the presence or absence of the chelating agent in the solution can be easily measured by performing the above quantification method. And the chelating agent can be quantified.

The method for quantifying a chelating agent according to the present invention includes a step of forming a solution by mixing the chelated incinerated ash with water and then removing the incinerated ash, and adding a predetermined amount of metal ions to the solution. It comprises a step and a step of quantifying the chelating agent in the solution based on the measurement of the turbidity of the solution to which the metal ion is added.

According to the method for quantifying a chelating agent according to the present invention, the turbidity of a solution to which a predetermined amount of metal ions is added is measured. If the chelating agent used when chelating the incineration ash remains in the solution, the solution will be suspended by the reaction between the remaining chelating agent and the metal ions, so that the chelating agent in the solution can be easily used. The presence or absence can be measured. Further, as the concentration of the remaining chelating agent increases, the turbidity of the solution to which the metal ion is added increases. Therefore, the presence or absence of the chelating agent in the solution can be easily measured by performing the above quantification method. And the chelating agent can be quantified.

In the method for quantifying a chelating agent according to the present invention, the metal ion may be a copper ion and the chelating agent may be a dithiocarbamic acid-based chelating agent. The dithiocarbamic acid-based chelating agent and the copper ion easily combine to form a copper complex insoluble in water, and the rate of increase in turbidity of the solution with respect to the amount of the chelating agent remaining in the solution. The lower the concentration of the chelating agent at the maximum measurable turbidity. Therefore, when copper ions are used, the quantifiable range of the chelating agent in the solution becomes wide.

In the method for quantifying a chelating agent according to the present invention, the metal ion may be a nickel ion and the chelating agent may be a dithiocarbamic acid-based chelating agent. The nickel complex formed by combining a dithiocarbamic acid-based chelating agent and nickel ions is insoluble in water and exists stably in a solution. As a result, when nickel ions are added to the solution, the presence or absence of the chelating agent remaining in the solution can be accurately measured. In addition, when nickel ions are added to the solution, the rate of increase in turbidity of the solution is high with respect to the amount of chelating agent remaining in the solution, so it is possible to accurately confirm whether or not the chelating agent remains. Even if the concentration of the residual chelating agent is very small, it can be quantified accurately.

In the method for quantifying a chelating agent according to the present invention, the turbidity of the solution may be measured by a transmitted light measurement method. When the turbidity of a solution is measured by the transmitted light measurement method, the measuring device used for the measurement can be manufactured at a lower cost and can be downsized as compared with, for example, a measuring device for measuring scattered light. As a result, the measuring device can be easily carried, and the turbidity of the solution can be easily measured even in a facility other than a specific facility.

In the chelating agent quantification system according to the present invention, a filtration unit that filters a slurry containing a measurement object containing a heavy metal insolubilized by the chelating agent and a predetermined amount of metal ions are mixed with the eluate eluted by the filtration unit. The chelating agent in the mixed solution is quantified from the turbidity of the mixed solution obtained by mixing the eluent and the metal ion, and the turbidity of the mixed solution obtained by the measuring section. It is provided with a quantitative unit to be used.

Further, in the chelating agent quantification system according to the present invention, a filtration unit for filtering a slurry containing incineration ash containing heavy metals insolubilized by the chelating agent and a predetermined amount of metal ions in the eluate eluted by the filtration unit. From the mixing unit to be mixed, the measuring unit for measuring the turbidity of the mixed solution obtained by mixing the eluent and metal ions, and the turbidity of the mixed solution obtained by the measuring unit, the chelating agent in the mixed solution is determined. It is provided with a quantification unit for quantification.

According to these chelating agent quantification systems according to the present invention, when an unreacted chelating agent is contained in the slurry, the chelating agent is contained in the eluate eluted in the filtration unit. Since the mixed solution obtained by mixing a predetermined amount of metal ions with this eluate is suspended by the reaction between the chelating agent and the metal ions, the presence or absence of the chelating agent can be easily measured. Further, since the turbidity of the mixed solution increases as the concentration of the chelating agent in the mixed solution increases, the presence or absence of the chelating agent in the solution can be easily measured by using the above-mentioned quantitative system, and the chelating agent can be used. Can be quantified.

In the method for quantifying a chelating agent according to the present invention, the chelating agent in a solution is quantified by measuring the turbidity of the solution after adding a predetermined amount of metal ions to the solution.

According to the method for quantifying a chelating agent according to the present invention, the turbidity of a solution to which metal ions are added is measured. Since the solution is suspended by the reaction between the chelating agent in the solution and the metal ion, the presence or absence of the chelating agent in the solution can be easily measured. Further, the higher the concentration of the chelating agent in the solution, the greater the turbidity of the solution to which the metal ion is added. Therefore, the chelating agent can be easily quantified by performing the above quantification method.

According to the present invention, it is possible to provide a chelating agent quantification method and a chelating agent quantification system capable of easily measuring the presence or absence of a chelating agent in a solution and quantifying the chelating agent in the solution.

It is a schematic block diagram which shows the chelating agent quantification system which concerns on 1st Embodiment of this invention. It is a flowchart for demonstrating the quantification method of the chelating agent which concerns on 1st Embodiment. It is a schematic block diagram which shows the chelating agent quantification system which concerns on 2nd Embodiment. It is a graph which shows the result of Table 1. It is a graph which shows the result of Table 2.

Hereinafter, a method for quantifying a chelating agent according to the present invention and a preferred embodiment of a chelating agent quantification system will be described with reference to the accompanying drawings. The following embodiments are examples for explaining the present invention, and the present invention is not limited to the following contents. Further, the attached drawings show an example of the embodiment, and the form and the ratio of the composition of the chelating agent quantification system are not construed as being limited to the drawings. The present invention can be appropriately modified and implemented within the scope of the gist thereof. In the following description, the same or equivalent elements are designated by the same reference numerals, and duplicate description will be omitted.

(First Embodiment)
FIG. 1 is a schematic configuration diagram showing a chelating agent quantification system according to the first embodiment of the present invention. The chelating agent quantification system 1 shown in FIG. 1 is a system for quantifying a chelating agent in a solution, for example, a system for calculating the concentration of the chelating agent. In the chelating agent quantification system 1 of the first embodiment, incineration ash composed of residue generated during incineration of waste and soot dust of exhaust gas (particularly flying ash in exhaust gas) is chelated with a chelating agent and chelated. In order to easily determine the presence or absence of a chelating agent (residual chelating agent) that elutes into the solution when the incineration ash is mixed in the solution, and to quantify the residual chelating agent (for example, calculate the concentration of the residual chelating agent). Used. Here, the chelate treatment is a treatment for forming a heavy metal complex that is insoluble or difficult to dissolve in an acid or the like by reacting a chelating agent with a heavy metal (for example, lead or the like) in the incineration ash, and is a heavy metal immobilization treatment. Also called. The chelating agent used for the chelating treatment is, for example, a dithiocarbamic acid-based chelating agent.

As shown in FIG. 1, the chelating agent quantification system 1 contains a filtration unit 2 for removing the incineration ash from the liquid in which the incineration ash after the chelate treatment is dispersed, and an eluent filtered by the filtration unit 2. The turbidity of the eluent accommodating unit 3, the metal ion accommodating unit 4 accommodating the metal ions, the mixing unit 5 for mixing the metal ions with the eluent in the eluent accommodating unit 3, and the mixed solution in the mixing unit 5. It includes a measuring unit 6 for measuring. Judgment and quantification of the presence or absence of residual chelating agent using the chelating agent quantification system 1 can be easily performed, for example, at a place where incinerated ash after chelation treatment is collected in an industrial waste incineration facility. It is preferable that the size is portable (for example, a size that can be accommodated in a hand-held bag) by an operator who collects the incinerated ash after the chelation treatment. Further, it is preferable that at least the filtration unit 2, the eluate storage unit 3, and the mixing unit 5 have a size that can be easily handled by an operator.

The filtration unit 2 is a device that filters a liquid (slurry) in which incineration ash after chelating treatment is dispersed, and is configured by attaching a filtration film so as to partition the inside of a cylinder such as a funnel into upper and lower parts. To. The cylinder in the filtration unit 2 is, for example, a cylinder, a square cylinder, a weight-shaped cylinder, or the like, and is made of glass, plastic, or resin. The membrane for filtration in the filtration unit 2 is, for example, a filter paper or an MF (membrane filter) provided so as to partition the inside of the cylinder. In the first embodiment, the liquid constituting the slurry filtered by the filtration unit 2 is water. The method of removing the incineration ash in the slurry in which the incineration ash is dispersed may be other than filtration. For example, the incineration ash may be removed from the slurry by allowing the incineration ash to settle by standing or centrifuging the slurry and then recovering the supernatant. In this case, the filtration unit 2 may be referred to as a removal unit.

The eluate accommodating unit 3 is an apparatus for accommodating the eluate eluted by the filtration unit 2, and is, for example, a glass or plastic cup-shaped container that transmits light. The opening of the eluate accommodating portion 3 may have a shape that fits with the side wall or the bottom surface of the filtration portion 2 to fix the filtration portion 2. The eluate accommodating portion 3 may have a lid portion that seals the opening in order to prevent leakage of the eluate.

The metal ion accommodating unit 4 is a device for accommodating a solution containing metal ions, such as a pipette or a syringe. The metal ion contained in the solution in the metal ion accommodating portion 4 is, for example, copper ion, nickel ion, cobalt ion, silver ion, or iron ion, and the solution is, for example, a copper sulfate solution, a nickel chloride solution, or a cobalt chloride solution. , Silver sulfate solution, or iron chloride solution. Copper ions or nickel ions are preferably used from the viewpoint of reacting the metal ions in the solution of the metal ion accommodating portion 4 with the residual chelating agent to form a water-insoluble substance (insoluble matter). The amount of metal ions in the metal ion accommodating portion 4 is adjusted to a predetermined amount.

The mixing unit 5 is an apparatus in which the eluate in the eluate accommodating unit 3 and the solution contained in the metal ion accommodating unit 4 are supplied and mixed to form a mixed solution, for example, glass that transmits light. Or it is a plastic cup-shaped container. The mixing unit 5 may be provided with a stirrer.

The measuring unit 6 is a device for measuring the turbidity of the mixed liquid in the mixing unit 5, and includes, for example, a portable light source and a light intensity measuring device. The measuring unit 6 is used for measuring the increase in turbidity due to the formation of insoluble matter in the mixed solution. The measurement of turbidity by the measuring unit 6 is performed by, for example, transmitted light measurement or scattered light measurement. The transmitted light measurement is a method of irradiating a mixed solution with light emitted from a light source, measuring the intensity of the transmitted light passing through the mixed solution with a light intensity measuring device, and obtaining it from a calibration curve prepared using a standard solution. Scattered light measurement is a method of irradiating a mixed solution with light emitted from a light source, measuring the intensity of the light scattered by the particles in the mixed solution with a light intensity measuring device, and obtaining it from a calibration line created using a standard solution. is there. The standard solution used by these measurement methods is, for example, a kaolin standard solution or a formazine standard solution. When the solution in the metal ion accommodating portion 4 is a coloring solution, the turbidity of the coloring solution may be measured in advance and the measured turbidity may be used as the background (that is, the turbidity of the coloring solution may be determined in advance. It may be measured and the turbidity of the coloring solution may be subtracted from the turbidity of the mixture). By the way, when the measurement width of the turbidity of the transmitted light measurement method is, for example, 20 degrees to 500 degrees, the measurement width of the scattered light measurement method is, for example, 0.01 to 1100 NTU (20 degrees to about 1000 degrees).

Since there is a correlation that the turbidity of the mixed solution increases as the concentration of the residual chelating agent increases in the mixed solution, the turbidity of the mixed solution obtained by the measuring unit 6 is used as the basis for the turbidity of the mixed solution. The chelating agent is quantified. The quantification of the residual chelating agent in the mixed solution is performed by a quantification unit (not shown). This quantification unit may be included in the measurement unit 6 of the chelating agent quantification system 1, or may be an apparatus different from the measurement unit 6. Further, the quantification of the residual chelating agent in the mixed solution may be performed by an operator. The quantification of the chelating agent may be carried out using, for example, a correspondence table (map) between the turbidity of the mixed solution and the concentration of the chelating agent, or may be carried out by various other means. This map may be included as electronic data in the quantitative unit, for example, or may be printed so that the operator can use it.

Next, the details of the chelating agent quantification method using the chelating agent quantification system 1 according to the first embodiment will be described with reference to FIG. FIG. 2 is a flowchart for explaining a method for quantifying the chelating agent according to the first embodiment.

First, the incineration ash generated during the incineration of industrial waste is chelated with a chelating agent. In this chelation treatment, a chelating agent is added to the incinerated ash to cause the heavy metal in the incinerated ash to react with the chelating agent to insolubilize (immobilize) the heavy metal. The amount of the chelating agent added in the chelation treatment is an amount that sufficiently reacts with the heavy metal in the incineration ash so that the heavy metal can be reliably determined to be insolubilized by the Ministry of the Environment Notification No. 13 test.

Next, as the first step, the incineration ash after the chelation treatment is mixed with water (step S1). In step S1, the incineration ash is mixed with water and then stirred (or shaken by a shaker), for example, to form a slurry in which the incineration ash after the chelation treatment is dispersed in water. Note that step S1 may be a pretreatment for using the chelating agent quantification system 1, and the chelating agent quantification system 1 is not necessarily used.

Next, as a second step, the eluate from which the incineration ash has been removed is extracted from the slurry formed in step S1 (step S2). In step S2, by flowing the slurry onto the membrane for filtration in the filtration unit 2, the liquid constituting the slurry passes through the membrane and is extracted into the eluent storage unit 3 as an eluent. On the other hand, the incineration ash constituting the slurry is removed from the eluate by remaining on the film. The filtration of the slurry by the filtration unit 2 is natural filtration, but may be pressure filtration or suction filtration.

Next, a predetermined amount of metal ions are added to the eluate in the eluate container 3 (step S3). In step S3, each of the eluate in the eluate accommodating unit 3 and the solution containing a predetermined amount of metal ions contained in the metal ion accommodating unit 4 is added to the mixing unit 5 to form a mixed solution. To do. In this mixed solution, the chelating agent that has not reacted with heavy metals by chelation treatment reacts with metal ions to form a metal complex that is insoluble in water. If it can be visually observed in step S3 that the mixed solution is suspended due to the metal complex, it may be determined that the mixed solution contains an unreacted chelating agent. The mixed solution may be formed by stirring the eluate to which the metal ion is added in step S3. When the mixing portion 5 is provided with a lid portion, it is preferable because it is possible to prevent the mixed liquid from scattering to the outside during stirring.

Next, the turbidity of the mixed solution in the mixing unit 5 is measured (step S4). In step S4, the turbidity of the mixed solution is measured by the measuring unit 6, and the residual chelating agent in the mixed solution is quantified based on the measurement result. The residual chelating agent in the mixed solution is quantified by utilizing the correlation that the turbidity of the mixed solution increases as the concentration of the residual chelating agent increases.

According to the chelating agent quantification system 1 according to the first embodiment described above, when an unreacted chelating agent is contained in the slurry, the chelating agent is contained in the eluate eluted by the filtration unit 2. .. The turbidity of the mixed solution obtained by mixing a predetermined amount of metal ions with this eluate sharply increases due to the formation of an insoluble metal complex obtained by the reaction of an unreacted chelating agent and metal ions. Here, since a predetermined amount of metal ions are added to the mixed solution, the turbidity of the mixed solution increases as the concentration of the chelating agent in the mixed solution increases until all the metal ions react. That is, in the mixed solution, there is a correlation between the concentration of the chelating agent and the turbidity. Utilizing this correlation, the chelating agent can be easily quantified after the turbidity of the mixed solution is measured by the measuring unit 6. Further, when the mixed solution is suspended due to the metal complex, the presence or absence of the chelating agent in the mixed solution can be easily determined by determining that the mixed solution contains an unreacted chelating agent.

Here, the point at which the turbidity in the mixed solution begins to rise sharply can be interpreted as the point at which the unreacted chelating agent begins to be contained in the slurry. Therefore, by measuring the inflection point of the turbidity change, an appropriate amount of the chelating agent added at the time of chelation treatment can be easily obtained (the method of measuring the inflection point of the turbidity change will be described later. Described in Examples).

In addition, in the present embodiment, the metal ion is a copper ion, and the chelating agent is a dithiocarbamic acid-based chelating agent, so that the dithiocarbamic acid-based chelating agent and the copper ion are easily bonded to water. Since an insoluble copper complex is formed and the rate of increase in the turbidity of the solution with respect to the amount of the chelating agent remaining in the solution is low, the concentration of the chelating agent at the maximum measurable turbidity is high. Therefore, when copper ions are used, the quantifiable range of the chelating agent in the solution becomes wide.

Further, in the present embodiment, since the metal ion is a nickel ion and the chelating agent is a dithiocarbamic acid-based chelating agent, the dithiocarbamic acid-based chelating agent easily binds to the nickel ion and is insoluble in water. Form a nickel complex. The nickel complex formed by combining a dithiocarbamic acid-based chelating agent and a nickel ion is insoluble in water and stably exists in a solution. As a result, when nickel ions are added to the solution, the presence or absence of the chelating agent remaining in the solution can be accurately measured. In addition, when nickel ions are added to the solution, the rate of increase in turbidity of the solution is high with respect to the amount of chelating agent remaining in the solution, so it is possible to accurately confirm whether or not the chelating agent remains. Even if the concentration of the residual chelating agent is very small, it can be quantified accurately.

Further, since the turbidity of the solution is measured by the transmitted light measurement method, the measuring device used for the measurement can be manufactured at a lower cost and can be downsized as compared with, for example, a measuring device for measuring scattered light. It becomes. As a result, the measuring device can be easily carried, and the turbidity of the solution can be easily measured even in a facility other than a specific facility.

(Second Embodiment)
Hereinafter, the chelating agent quantification system according to the second embodiment and the chelating agent quantification method using the system will be described. In the description of the second embodiment, the description overlapping with the first embodiment is omitted, and the part different from the first embodiment is described. That is, the description of the first embodiment may be appropriately used for the second embodiment to the extent technically possible.

FIG. 3 is a schematic configuration diagram showing a chelating agent quantification system according to the second embodiment. As shown in FIG. 3, the chelating agent quantification system 1A of the second embodiment does not include the metal ion accommodating portion 4 and the mixing portion 5 as compared with the chelating agent quantification system 1 of the first embodiment, instead of providing. It includes a mixing unit 5A and a slurry accommodating unit 7.

The mixing unit 5A previously contains a solution containing a predetermined amount of metal ions, and the eluate is supplied from the eluate storage unit 3 to form a mixed solution. Therefore, the mixing unit 5A is an apparatus for mixing the metal ions in the solution with the eluate, similarly to the mixing unit 5 of the first embodiment. Further, since the turbidity of the mixed liquid in the mixing unit 5A is measured by the measuring unit 6, the mixing unit 5A is a glass or plastic cup-shaped container that transmits light like the mixing unit 5.

The slurry storage unit 7 is a device (storage unit) for storing the slurry, for example, a plastic container. In order to increase the dispersity of the incineration ash in the liquid to form a slurry, the slurry storage unit 7 may contain, for example, a plurality of balls for crushing the incineration ash. In this case, the slurry accommodating portion 7 is provided with a lid for preventing the outflow of liquid when the incineration ash is crushed using a ball to increase the degree of dispersion. Further, the degree of dispersion of the incinerated ash in the liquid may be increased by using a stir bar or the like instead of the balls.

Next, the details of the chelating agent quantification method using the chelating agent quantification system 1A according to the second embodiment will be described. The method for quantifying the chelating agent of the second embodiment has the same steps as steps S1 to S4 in the quantification method of the first embodiment. Therefore, the method for quantifying the chelating agent of the second embodiment will be described below with reference to FIG.

First, in step S1 of the second embodiment, after the incineration ash is mixed with the water in the slurry storage unit 7, a plurality of balls are stored in the slurry storage unit 7. Next, after sealing the slurry accommodating portion 7 with a lid, the slurry accommodating portion 7 is vibrated for several tens of seconds to several minutes. As a result, the incinerated ash after the chelate treatment forms a slurry dispersed in water.

Next, in step S2 of the second embodiment, the eluate obtained by removing the incineration ash from the slurry formed in step S1 is extracted in the same manner as in step S2 of the first embodiment.

Next, in step S3 of the second embodiment, the eluate in the eluate accommodating section 3 is added to the mixing section 5A to add a predetermined amount of metal ions to the eluate to generate a mixed solution. In step S3, it is preferable to stir the mixed solution by vibrating the mixing section 5A after sealing it.

Next, in step S4 of the second embodiment, the turbidity of the mixed solution is measured by the measuring unit 6 as in step S4 of the first embodiment, and the residual chelating agent in the mixed solution is determined based on the measurement result. Quantify.

The chelating agent quantification system 1A according to the second embodiment described above can also exert the same action and effect as the first embodiment.

Although the preferred embodiment of the present invention has been described, the present invention is not limited to the above embodiment. For example, in the first embodiment, the filtration unit 2, the eluate storage unit 3, the metal ion storage unit 4, the mixing unit 5, and the measurement unit 6 in the chelating agent quantification system 1 are separate devices, for example. The filtration unit 2 and the eluate accommodating unit 3 may be an integrated device, and the eluent accommodating unit 3 and the mixing unit 5 may be an integrated device, and the eluent accommodating unit 3, the mixing unit 5, And the measuring unit 6 may be an integrated device, and the mixing unit 5 and the measuring unit 6 may be an integrated device. In addition, the chelating agent quantification system 1 may further include a mixing unit (corresponding to the slurry accommodating unit 7 of the second embodiment) for mixing the incineration ash that has been chelated into water to form a slurry. Further, the incinerated ash may be solidified before the chelate treatment. In this case, by measuring the presence or absence of the residual chelating agent, it can be easily determined whether or not the solidification treatment has been sufficiently performed. In addition, by quantifying the residual chelating agent, the amount of material required for the solidification treatment can be estimated.

In the second embodiment, the incinerated ash in the slurry container 7 may be dispersed by using a stirrer or a shaker. Further, the filtration unit 2 and the eluate accommodating unit 3 may be integrated, the eluate accommodating unit 3 and the mixing unit 5A may be integrated, and the mixing unit 5A and the measuring unit 6 may be integrated. It may be an integrated device.

Further, in the first and second embodiments, the eluate accommodating unit 3 may be a pipette, a syringe, or the like that extracts the eluate from the slurry via the filtration unit 2. In this case, the filtration unit 2 may be a filter that can be detachably attached to the eluate storage unit 3. As a result, when the eluate accommodating unit 3 extracts the eluate from the slurry, the filtration unit 2 is attached to the eluate accommodating unit 3. Further, when the eluate is added from the eluate accommodating unit 3 to the mixing units 5 and 5A, the filtration unit 2 is removed from the eluate accommodating unit 3.

Further, in the first and second embodiments, the chelating agent quantification method using the chelating agent quantification system may be performed entirely automatically, partially automatically, or all manually. You may be chelated. That is, a part or all of the above-mentioned chelating agent quantification method may be performed by an operator, or may be automatically performed by an arithmetic unit or the like.

Further, in the first and second embodiments, the presence or absence of a residual chelating agent in incinerated ash (particularly fly ash) was measured and quantified using a chelating agent quantification system, but the present invention is not limited to this. You may. For example, as a measurement object other than incineration ash, a chelate quantification method using the chelate quantification system according to the present invention may be carried out on contaminated soil. When the soil is contaminated with heavy metals, for example, it is necessary to carry out heavy metal containment treatment (corresponding to detoxification treatment of incineration ash) on the soil. By performing the chelate quantification method using the chelating agent quantification system according to the present invention on the soil in which the heavy metal containment treatment has been carried out, it can be easily confirmed whether or not the containment treatment has been sufficiently performed. In addition, if the containment treatment is not sufficient, the amount of additional drug to be added can be estimated. When a chelating agent is used as the heavy metal containment treatment, the heavy metal containment treatment is regarded as a chelate treatment.

Further, in order to investigate whether or not the soil is contaminated with heavy metals, a chelate quantification method using the chelate quantification system according to the present invention may be carried out. That is, the object to be measured may be soil that has not been subjected to heavy metal containment treatment or the like. In this case, after performing a chelating treatment in which an appropriate amount of chelating agent is added to the soil to be measured, the residual chelating agent is quantified. As a result, the degree of soil contamination by heavy metals can be estimated, and it can be easily determined whether or not heavy metal containment treatment is necessary.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

(Example 1)
Fly ash generated when industrial waste was incinerated was recovered, and a chelating agent having a predetermined concentration was added to the fly ash for chelation treatment. As the chelating agent, a TS-300 piperazine-based chelating agent manufactured by Tosoh Corporation was used. 10 g of fly ash after the chelating treatment was mixed in 100 ml of water (purified water), stirred with a stirrer for 5 minutes, and then the water in which the fly ash was dispersed was filtered using a funnel and a filter paper. The filter paper is manufactured by Advantech Toyo Co., Ltd., No. 1 for qualitative analysis. 101 was used. A measurement sample was prepared by adding 0.12 ml of a 0.02 mol / L copper sulfate aqueous solution to the filtrate extracted by filtration and mixing.

The turbidity of the prepared measurement sample was measured by a transmitted light measurement method using a formazine standard solution. This transmitted light measurement was performed using an LED as a light source and a digital turbidity meter 500G manufactured by Kyoritsu Rikagaku Kenkyusho Co., Ltd. as a turbidity meter. The measurement wavelength of the turbidity meter was 660 nm, and the measurement range of turbidity was 20 to 500 degrees. As for the turbidity, 1 mg of formazine, which is a standard substance, was contained in 1 L of purified water, and the turbidity of the suspension uniformly dispersed was 1 degree. The measurement results of the measurement sample of Example 1 are shown in Table 1. When the turbidity was 20 or less, the concentration of the chelating agent was set to 0, and when the turbidity was 500 or more, the concentration of the chelating agent could not be measured.

FIG. 4 is a graph showing the results of Table 1. In FIG. 4, the horizontal axis shows the amount of the chelating agent added, the vertical axis on the left side shows the turbidity, and the vertical axis on the right side shows the concentration of the chelating agent in the measurement sample. The triangles 11a to 11e in FIG. 4 are the concentrations of the chelating agent, and the diamonds 12a to 12e in FIG. 4 are the turbidity of the measurement sample. As shown in Table 1, when the amount of the chelating agent added is 0 wt% to 6 wt%, the turbidity hardly changes. Therefore, the inclination of the straight line 13 connecting the diamonds 12b and 12c in FIG. 4 is very small. This is because the chelating agent added during the chelating treatment sufficiently reacts with the heavy metals in the flying ash, and the chelating agent is completely or almost not contained in the measurement sample, so that the metal ions (copper) in the measurement sample are contained. It is considered that this is because the chelating agent does not react with the ion) and no water-insoluble substance is formed.

On the other hand, as shown in Table 1, when the amount of the chelating agent added is 7 wt% to 8 wt%, the turbidity increases sharply. Therefore, the inclination of the straight line 14 connecting the diamonds 12d and 12e in FIG. 4 is much larger than the inclination of the straight line 13. This is because an excess chelating agent is added during the chelation treatment and the chelating agent remaining in the measurement sample is contained. Therefore, copper ions in the measurement sample react with the residual chelating agent and are insoluble in water (water-insoluble substance). It is considered that this is because the copper complex) is formed and the turbidity of the measurement sample rises sharply. Since the measurement sample contains copper ions adjusted to a predetermined amount, the amount of copper complex formed changes depending on the concentration of the residual chelating agent. That is, the amount of change in the turbidity of the measurement sample is determined by the concentration of the residual chelating agent. From this, it can be seen that there is a correlation between the turbidity of the measurement sample and the concentration of the residual chelating agent.

The intersection 15 of the straight lines 13 and 14 corresponds to the point where the copper complex begins to be formed in the mixed solution. That is, the intersection 15 corresponds to the point where the heavy metal in the fly ash and the chelating agent just react in the chelating treatment. In other words, the intersection 15 is a point indicating a threshold value for determining the presence or absence of the chelating agent in the measurement sample, and is an inflection point of the straight lines 13 and 14. Therefore, in Example 1, by obtaining the straight lines 13 and 14, the intersection point 15 which is an appropriate amount of the chelating agent added in the chelation treatment can be easily obtained.

(Example 2)
An M-1 dithiocarbamic acid-based chelating agent manufactured by Miyoshi Oil & Fat Co., Ltd. was used as the chelating agent, the filtrate extracted by filtration was diluted 5-fold, and a 0.04 mol / L nickel chloride aqueous solution was added to the diluted filtrate. A measurement sample was prepared in the same manner as in Example 1 except that a measurement sample was prepared by adding 0.6 ml of the above. Then, the turbidity of this measurement sample was measured in the same manner as in Example 1. The measurement results of the measurement sample of Example 2 are shown in Table 2.

FIG. 5 is a graph showing the results of Table 2. In FIG. 5, the horizontal axis shows the amount of the chelating agent added, the vertical axis on the left side shows the turbidity, and the vertical axis on the right side shows the concentration of the chelating agent in the measurement sample. The triangles 21a to 21f in FIG. 5 are the concentrations of the chelating agent, and the diamonds 22a to 22f in FIG. 5 are the turbidity of the measurement sample. As shown in Table 2, when the amount of the chelating agent added is 0 wt% to 6 wt%, the turbidity hardly changes. Therefore, the inclination of the straight line 23 connecting the diamonds 22b and 22c in FIG. 5 is very small. This is because, as described in Example 1, the chelating agent added during the chelating treatment sufficiently reacts with the heavy metal in the fly ash, and the measurement sample contains no or almost no chelating agent. it is conceivable that.

On the other hand, as shown in Table 2, when the amount of the chelating agent added is 7 wt% to 9 wt%, the turbidity is significantly increased. Therefore, the inclination of the straight line 24 connecting the diamonds 22d to 22f in FIG. 5 is larger than the inclination of the straight line 23. It is considered that this is because, as described in Example 1, the nickel ions in the measurement sample reacted with the residual chelating agent to form a water-insoluble substance (nickel complex). Since the measurement sample contains nickel ions adjusted to a predetermined amount, the amount of nickel complex formed changes depending on the concentration of the residual chelating agent. Therefore, even in Example 2, it can be seen that there is a correlation between the turbidity of the measurement sample and the concentration of the residual chelating agent. The rate of increase in turbidity of the solution with respect to the amount of the residual chelating agent in Example 2 is larger than that in Example 1.

The intersection 25 of the straight lines 23 and 24 corresponds to the point at which the nickel complex begins to be formed in the mixed solution. That is, the intersection 25 corresponds to the point where the heavy metal in the fly ash and the chelating agent just react in the chelating treatment. Therefore, also in Example 2, by obtaining the straight lines 23 and 24, the intersection point 25, which is an appropriate amount of the chelating agent added in the chelation treatment, can be easily obtained.

1 ... chelating agent quantification system, 2 ... filtration unit, 3 ... eluate storage unit, 4 ... metal ion storage unit, 5 ... mixing unit, 6 ... measurement unit.

The present invention relates to chelating agents quantification system.

The present invention has been made to solve the above problems, that easily whether the chelating agent in the solution can be measured, and the chelating agent in the solution to provide a quantitative can Ruki chelating agent quantification system The purpose.

According to the present invention, it can be easily measured whether the chelating agent in the solution, and the chelating agent in the solution can provide a quantitative can Ruki chelating agent quantification system.

Claims (8)

A step of forming a solution by mixing the chelated object to be measured with water and then removing the object to be measured.
The step of adding a predetermined amount of metal ions to the solution and
A step of quantifying the chelating agent in the solution based on the measurement of the turbidity of the solution to which the metal ion is added, and
A method for quantifying a chelating agent. A step of forming a solution by mixing the chelated incineration ash with water and then removing the incineration ash.
The step of adding a predetermined amount of metal ions to the solution and
A step of quantifying the chelating agent in the solution based on the measurement of the turbidity of the solution to which the metal ion is added, and
A method for quantifying a chelating agent. The method for quantifying a chelating agent according to claim 1 or 2, wherein the metal ion is a copper ion and the chelating agent is a dithiocarbamic acid-based chelating agent. The method for quantifying a chelating agent according to claim 1 or 2, wherein the metal ion is a nickel ion and the chelating agent is a dithiocarbamic acid-based chelating agent. The method for quantifying a chelating agent according to any one of claims 1 to 4, wherein the turbidity of the solution is measured by a transmitted light measurement method. A filtration unit that filters a slurry in which a measurement object containing a heavy metal insolubilized by a chelating agent is dispersed.
A mixing unit that mixes a predetermined amount of metal ions with the eluate eluted in the filtration unit,
A measuring unit for measuring the turbidity of the mixed solution obtained by mixing the eluate and the metal ions,
A quantification unit for quantifying the chelating agent in the mixture from the turbidity of the mixture obtained by the measurement unit, and a quantification unit.
A chelating agent quantification system comprising. A filtration unit that filters a slurry in which incineration ash containing heavy metals insolubilized by a chelating agent is dispersed.
A mixing unit that mixes a predetermined amount of metal ions with the eluate eluted in the filtration unit,
A measuring unit for measuring the turbidity of the mixed solution obtained by mixing the eluate and the metal ions,
A quantification unit for quantifying the chelating agent in the mixture from the turbidity of the mixture obtained by the measurement unit, and a quantification unit.
A chelating agent quantification system comprising. A method for quantifying a chelating agent, which quantifies the chelating agent in the solution by measuring the turbidity of the solution after adding a predetermined amount of metal ions to the solution.

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