JP2016183960A - Method and system for determining quantity of chelate agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a system for determining the quantity of a chelate agent that can easily detect the presence or absence and determine the quantity of a chelate agent in a solution.SOLUTION: The method for determining the quantity of a chelate agent includes the steps of: mixing a chelated measurement object with water and removing burned ashes, thereby obtaining a solution; adding a specific quantity of metal ions into the solution; and determining the quantity of a chelate agent in the solution based on the measured turbidity of the solution with the metal ions added. With the method, the presence or absence of the chelate agent in the solution can be easily detected based on the presence or absence of a metal complex generated in the solution, and the quantity of the chelate agent can be easily determined based on the measured turbidity of the solution.SELECTED DRAWING: Figure 2

Description

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

  Residues generated when incinerating industrial wastes and incineration ash of exhaust gas (particularly fly ash in exhaust gas) may contain heavy metals. The heavy metal contained in such incineration ash needs 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 chelating agent (insolubilization treatment), and the like. When performing insolubilization treatment, it is common to add excess chelating agent to the incinerated ash in order to reliably determine that heavy metals are insolubilized by the Ministry of the Environment Notification No. 13 method test. However, since the above-mentioned chelating agent is not easily decomposed naturally and is expensive, a method for easily obtaining an appropriate amount of chelating agent to be added to the incinerated ash in the insolubilization process has been proposed.

  For example, in Patent Document 1 below, in order to obtain a necessary amount of chelating agent in the insolubilization treatment of heavy metals, an eluate obtained by eluting water mixed with incineration ash 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 excess chelating agent (that is, unreacted chelating agent with heavy metal) in the eluate is determined based on the presence or absence of coloring of the mixed solution when the reagent is added to the eluate.

JP 2004-216209 A

  In the case of the technique described in Patent Document 1, since the determination is based only on the presence or absence of coloring of the liquid mixture, the presence or absence of excess chelating agent can be easily determined, but obtaining the amount of excess chelating agent is not possible. Can not.

  The present invention has been made to solve such a problem, and can easily determine the presence or absence of a chelating agent in a solution and can determine the amount of the chelating agent in the solution. The purpose is to provide.

  The chelating agent quantification method according to the present invention comprises a step of forming a solution by mixing a measurement object subjected to chelation treatment into water and then removing the measurement object, and a predetermined amount of metal ions in the solution. And a step of quantifying the chelating agent in the solution based on measurement of the turbidity of the solution to which the metal ions have been added.

  According to the chelating agent quantification method of 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 in chelating the measurement object remains in the solution, the solution is suspended by the reaction between the remaining chelating agent and metal ions, so the chelating agent in the solution can be easily The presence or absence of can be measured. In addition, the higher the concentration of the remaining chelating agent, the greater the turbidity of the solution to which the metal ions are added, so the presence or absence of the chelating agent in the solution can be easily measured by performing the above quantitative method. And the chelating agent can be quantified.

  The chelating agent quantification method according to the present invention includes a step of forming a solution by mixing the incinerated ash that has been chelated with water, and then removing the incinerated ash, and adding a predetermined amount of metal ions to the solution. And a step of quantifying the chelating agent in the solution based on measurement of the turbidity of the solution to which the metal ions have been added.

  According to the chelating agent quantification method of 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 incinerated ash remains in the solution, the solution will be suspended by the reaction between the remaining chelating agent and the metal ions. The presence or absence can be measured. In addition, the higher the concentration of the remaining chelating agent, the greater the turbidity of the solution to which the metal ions are added, so the presence or absence of the chelating agent in the solution can be easily measured by performing the above quantitative method. And the chelating agent can be quantified.

  In the chelating agent determination method according to the present invention, the metal ion may be a copper ion, and the chelating agent may be a dithiocarbamic acid chelating agent. The dithiocarbamic acid-based chelating agent and copper ion easily combine to form a copper complex that is insoluble in water, and the rate of increase in turbidity of the solution relative to the amount of chelating agent remaining in the solution is Since it is low, the chelator concentration at the highest measurable turbidity is high. Therefore, when copper ions are used, the quantifiable range of the chelating agent in the solution is widened.

  In the chelating agent determination method according to the present invention, the metal ion may be nickel ion, and the chelating agent may be a dithiocarbamic acid chelating agent. A nickel complex formed by combining a dithiocarbamic acid chelating agent and nickel ions is insoluble in water and stably exists in solution. Thereby, when nickel ion is 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 the turbidity of the solution relative to the amount of chelating agent remaining in the solution is high, so that it can be confirmed accurately whether the chelating agent remains, Even if the concentration of the remaining chelating agent is very small, it can be accurately determined.

  In the chelating agent quantification method according to the present invention, the turbidity of the solution may be measured by a transmitted light measurement method. When measuring the turbidity of a solution by the transmitted light measurement method, the measuring device used for the measurement can be manufactured at a lower cost and can be reduced in size compared with, for example, a measuring device for measuring scattered light. This makes it easy to carry the measuring device, and the turbidity of the solution can be easily measured even outside a specific facility.

  The chelating agent quantification system according to the present invention includes a filtration unit for filtering a slurry containing a measurement object containing a heavy metal insolubilized by a chelating agent, and a predetermined amount of metal ions mixed in the eluate eluted by the filtration unit. Quantifying the chelating agent in the mixture from the mixing part, the measurement part that measures the turbidity of the mixture obtained by mixing the eluate and metal ions, and the turbidity of the mixture obtained in the measurement part And a quantification unit.

  Further, the chelating agent quantification system according to the present invention includes a filtration unit that filters the slurry containing incinerated ash containing heavy metal insolubilized by the chelating agent, and a predetermined amount of metal ions in the eluate eluted by the filtration unit. From the mixing part to be mixed, the measuring part for measuring the turbidity of the mixed liquid obtained by mixing the eluate and metal ions, and the turbidity of the mixed liquid obtained in the measuring part, the chelating agent in the mixed liquid is determined. 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 by the filtration unit. Since the mixture obtained by mixing a predetermined amount of metal ions with the 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 quantitative system, and the chelating agent is Can be quantified.

  The chelating agent quantification method according to the present invention 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.

  According to the chelating agent quantification method of 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 and the metal ion in the solution, the presence or absence of the chelating agent in the solution can be easily measured. Moreover, since the turbidity of the solution to which metal ions are added increases as the concentration of the chelating agent in the solution increases, the chelating agent can be easily quantified by performing the above-described quantification method.

  ADVANTAGE OF THE INVENTION According to this invention, the determination method of the chelating agent which can measure the presence or absence of the chelating agent in a solution easily, and can quantify the chelating agent in a solution, and a chelating agent determination system can be provided.

It is a schematic block diagram which shows the chelating agent fixed_quantity | assay system which concerns on 1st Embodiment of this invention. It is a flowchart for demonstrating the determination method of the chelating agent which concerns on 1st Embodiment. It is a schematic block diagram which shows the chelating agent fixed_quantity | assay 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.

  Preferred embodiments of a chelating agent quantification method and a chelating agent quantification system according to the present invention will be described below 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 accompanying drawings show an example of the embodiment, and the form of the chelating agent determination system and the ratio of the components are not to be interpreted as being limited to the drawings. The present invention can be implemented with appropriate modifications within the scope of the gist thereof. In the following description, the same or corresponding elements are denoted by the same reference numerals, and redundant description is omitted.

(First embodiment)
FIG. 1 is a schematic configuration diagram showing a chelating agent quantitative system according to the first embodiment of the present invention. A 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 determination system 1 in the first embodiment, incineration ash composed of residue generated during incineration of waste and dust of exhaust gas (particularly fly ash in exhaust gas) is chelated with a chelating agent and chelated. To easily determine the presence or absence of a chelating agent (residual chelating agent) that elutes into the solution when incinerated ash is mixed into the solution, and to quantify the residual chelating agent (for example, to 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 (such as lead) in the incinerated ash, and is a heavy metal immobilization treatment. Also called. The chelating agent used for the chelation treatment is, for example, a dithiocarbamic acid chelating agent.

  As shown in FIG. 1, the chelating agent determination system 1 contains a filtration unit 2 that removes the incineration ash from the liquid in which the incineration ash after chelation is dispersed, and an eluate that has been filtered by the filtration unit 2. The eluate storage part 3, the metal ion storage part 4 for storing metal ions, the mixing part 5 for mixing metal ions with the eluate in the eluate storage part 3, and the turbidity of the mixed liquid in the mixing part 5 And a measuring unit 6 for measuring. The determination and quantification of the presence or absence of residual chelating agent using the chelating agent quantification system 1 can be easily performed at a place where the incinerated ash after chelation treatment is collected in an incineration facility for industrial waste, for example. It is preferable that the worker who collects the incinerated ash after the chelation treatment has a size that can be carried (for example, a size that can be accommodated in a hand-held bag). Moreover, 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's hand.

  The filtration unit 2 is a device for filtering the liquid (slurry) in which the incinerated ash after the chelate treatment is dispersed, and is configured by attaching a membrane for filtration so as to partition the inside of a cylindrical body such as a funnel vertically. The The cylinder in the filtration unit 2 is, for example, a cylinder, a square cylinder, or a weight cylinder, and is made of glass, plastic, or resin. The membrane for filtration in the filtration unit 2 is, for example, filter paper or MF (membrane filter) provided so as to partition the inside of the cylinder. In 1st Embodiment, the liquid which comprises the slurry filtered by the filtration part 2 is water. The method for 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 collecting the supernatant after allowing the incineration ash to settle by standing or centrifuging the slurry. In this case, the filtration unit 2 may be referred to as a removal unit.

  The eluate storage unit 3 is a device that stores 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 storage part 3 may be shaped to fit the side wall or bottom surface of the filtration part 2 and fix the filtration part 2. The eluate storage part 3 may have a lid for sealing the opening in order to prevent leakage of the eluate.

  The metal ion storage unit 4 is a device that stores a solution containing metal ions, such as a pipette or a syringe. The metal ions contained in the solution in the metal ion storage unit 4 are, for example, copper ions, nickel ions, cobalt ions, silver ions, or iron ions. Examples of the solution include a copper sulfate solution, a nickel chloride solution, and a cobalt chloride solution. Silver sulfate solution or iron chloride solution. From the viewpoint of reacting metal ions in the solution of the metal ion storage unit 4 with the residual chelating agent to form a substance insoluble in water (insoluble matter), it is preferable to use copper ions or nickel ions. In addition, the metal ion in the metal ion accommodating part 4 is adjusted so that it may become predetermined amount.

  The mixing unit 5 is a device that is supplied with the eluate in the eluate storage unit 3 and the solution stored in the metal ion storage unit 4 and mixes them 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 that measures 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 an increase in turbidity due to insoluble matter formation in the mixed solution. The turbidity measurement by the measurement unit 6 is performed, for example, by transmitted light measurement or scattered light measurement. Transmitted light measurement is a technique in which the intensity of transmitted light that has passed through a liquid mixture after irradiating light emitted from a light source is measured by a light intensity measuring instrument, and obtained from a calibration curve created using a standard solution. Scattered light measurement is a technique in which light emitted from a light source is irradiated onto a liquid mixture, the intensity of light scattered by particles in the liquid mixture is measured with a light intensity measuring instrument, and obtained from a calibration curve created using a standard liquid. is there. The standard solution used by these measuring methods is, for example, a kaolin standard solution or a formazine standard solution. In addition, when the solution in the metal ion storage unit 4 is a colored solution, the turbidity of the colored solution is measured in advance, and the measured turbidity may be used as the background (that is, the turbidity of the colored solution is set in advance). Measure and subtract the turbidity of the colored solution from the turbidity of the mixture). Incidentally, when the turbidity measurement width 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).

  In the mixed solution, there is a correlation that the turbidity of the mixed solution increases as the concentration of the residual chelating agent increases. Therefore, based on the turbidity of the mixed solution obtained by the measuring unit 6, 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 a device different from the measurement unit 6. Further, the quantitative determination of the residual chelating agent in the mixed solution may be performed by an operator. The quantification of the chelating agent may be performed, for example, using a correspondence table (map) between the turbidity of the mixed solution and the concentration of the chelating agent, or may be performed by various other means. This map may be included as electronic data in the quantification unit, for example, or may be printed so as to be usable by an operator.

  Next, details of a 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 the chelating agent quantification method according to the first embodiment.

  First, incineration ash generated during incineration of industrial waste is chelated with a chelating agent. In this chelate treatment, by adding a chelating agent to the incinerated ash, the heavy metal in the incinerated ash is reacted with the chelating agent to insolubilize (fix) the heavy metal. The addition amount of the chelating agent in the chelate treatment is an amount that sufficiently reacts with the heavy metal in the incineration ash in order to reliably determine that the heavy metal is insolubilized by the Ministry of the Environment Notification No. 13 method test.

  Next, as a first step, the incinerated ash after the chelate treatment is mixed in water (step S1). In step S1, after mixing incineration ash with water, it stirs, for example with a stirrer (or shakes with a shaker), and forms the slurry by which the incineration ash after chelate processing was disperse | distributed in water. In addition, step S1 is good also as a pre-process for using the said chelating agent fixed_quantity | assay system 1, and does not necessarily use the said chelating agent fixed_quantity | quantitative_assay system 1 concerned.

  Next, as a second step, an eluate from which the incinerated ash has been removed is extracted from the slurry formed in step S1 (step S2). In step S <b> 2, the slurry is allowed to flow onto the filtration membrane in the filtration unit 2, so that the liquid constituting the slurry passes through the membrane and is extracted into the eluate storage unit 3 as an eluate. On the other hand, the incineration ash constituting the slurry is removed from the eluate by remaining on the membrane. Although the filtration of the slurry by the filtration part 2 is natural filtration, pressurization filtration or suction filtration may be sufficient.

  Next, a predetermined amount of metal ions is added to the eluate in the eluate container 3 (step S3). In step S3, each of the eluate in the eluate container 3 and the solution containing a predetermined amount of metal ions stored in the metal ion container 4 is added to the mixing unit 5 to form a mixed liquid. To do. In this mixed solution, a chelating agent that has not reacted with the heavy metal by chelation reacts with the metal ion to form a metal complex that is insoluble in water. In step S3, when it can be visually observed that the mixed solution is suspended due to the metal complex, it may be determined that the unreacted chelating agent is contained in the mixed solution. In addition, you may form a liquid mixture by stirring the eluate to which the metal ion was added in step S3. When the mixing part 5 is provided with a lid part, it is preferable because the liquid mixture can be prevented from splashing 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 using the correlation that the turbidity of the mixed solution increases as the concentration of the remaining chelating agent increases.

  According to the chelating agent determination system 1 according to the first embodiment described above, when an unreacted chelating agent is included in the slurry, the chelating agent is included 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 the eluate rapidly increases due to the formation of an insoluble metal complex obtained by the reaction between the unreacted chelating agent and the metal ions. Here, since a predetermined amount of metal ions is 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 have reacted. That is, in the mixed solution, there is a correlation between the concentration of the chelating agent and 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 unreacted chelating agent is contained in the mixed solution.

  Here, the point at which the turbidity in the mixed solution starts to increase 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, it is possible to easily obtain an appropriate amount of addition of the chelating agent at the time of the chelate treatment (a method for measuring the inflection point of the turbidity change is described later. This will be explained in Examples).

  In addition, in this embodiment, the metal ion is a copper ion, and the chelating agent is a dithiocarbamic acid chelating agent, so that the dithiocarbamic acid chelating agent and the copper ion are easily bonded to water. Since the rate of increase in turbidity of the solution relative to the amount of chelating agent that forms insoluble copper complexes and remains 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 is widened.

  In the present embodiment, the metal ions are nickel ions, and the chelating agent is a dithiocarbamic acid chelating agent, so that the dithiocarbamic acid chelating agent easily binds to nickel ions and is insoluble in water. A nickel complex is formed. A nickel complex formed by combining a dithiocarbamic acid chelating agent and nickel ions is insoluble in water and exists stably in a solution. Thereby, when nickel ion is 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 the turbidity of the solution relative to the amount of chelating agent remaining in the solution is high, so that it can be confirmed accurately whether the chelating agent remains, Even if the concentration of the remaining chelating agent is very small, it can be accurately determined.

  In addition, the measurement of the turbidity of the solution is performed by the transmitted light measurement method, so that the measurement device used for the measurement can be manufactured at a lower cost and can be reduced in size compared with, for example, a measurement device for measuring scattered light. It becomes. This makes it easy to carry the measuring device, and the turbidity of the solution can be easily measured even outside a specific facility.

(Second Embodiment)
Hereinafter, a chelating agent quantification system according to the second embodiment and a chelating agent quantification method using the system will be described. In the description of the second embodiment, descriptions overlapping with the first embodiment are omitted, and only the parts different from the first embodiment are described. In other words, the description of the first embodiment may be used as appropriate for the second embodiment within the technically possible range.

  FIG. 3 is a schematic configuration diagram showing a chelating agent determination system according to the second embodiment. As shown in FIG. 3, the chelating agent determination system 1A of the second embodiment is not provided with the metal ion storage unit 4 and the mixing unit 5 as compared with the chelating agent determination system 1 of the first embodiment. 5A of mixing parts and the slurry accommodating part 7 are provided.

  The mixing unit 5A stores a solution containing a predetermined amount of metal ions in advance, and forms a mixed solution when the eluate is supplied from the eluate storage unit 3. Therefore, the mixing unit 5A is a device that mixes metal ions in the solution with the eluate, similarly to the mixing unit 5 of the first embodiment. Moreover, since the turbidity of the liquid mixture 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 in the same manner as the mixing unit 5.

  The slurry accommodating portion 7 is a device (accommodating portion) that accommodates slurry, and is, for example, a plastic container. In order to increase the degree of dispersion of the incinerated ash in the liquid to form a slurry, the slurry container 7 may accommodate, for example, a plurality of balls for pulverizing the incinerated ash. In this case, the slurry container 7 includes a lid for preventing the outflow of liquid when the incinerated ash is pulverized using a ball to increase the degree of dispersion. Further, the dispersion degree of the incinerated ash in the liquid may be increased by using a stirring rod or the like instead of the ball.

  Next, details of the chelating agent quantification method using the chelating agent quantification system 1A according to the second embodiment will be described. The chelating agent quantification method of the second embodiment has the same steps as steps S1 to S4 in the quantification method of the first embodiment. For this reason, below, the determination method of the chelating agent of 2nd Embodiment is demonstrated, using FIG.

  First, in step S <b> 1 of the second embodiment, after incineration ash is mixed into the water in the slurry container 7, a plurality of balls are accommodated in the slurry container 7. Next, after sealing the slurry container 7 using a lid, the slurry container 7 is vibrated for several tens of seconds to several minutes. This forms a slurry in which the incinerated ash after chelation is dispersed in water.

  Next, in step S2 of the second embodiment, the eluate from which the incinerated ash has been removed is extracted from the slurry formed in step S1, as in step S2 of the first embodiment.

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

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

  The same effect as 1st Embodiment can be show | played also by 1A of chelating agent fixed_quantity | assay systems which concern on 2nd Embodiment demonstrated above.

  In addition, although preferred embodiment of this invention was described, this invention is not limited to the said embodiment. For example, in 1st Embodiment, although the filtration part 2, the eluate accommodating part 3, the metal ion accommodating part 4, the mixing part 5, and the measurement part 6 in the chelating agent fixed_quantity | assay system 1 are each separate apparatuses, The filtration unit 2 and the eluate storage unit 3 may be an integrated device, and the eluate storage unit 3 and the mixing unit 5 may be an integrated device. The eluate storage unit 3, the mixing unit 5, And the measurement part 6 may be an integral apparatus, and the mixing part 5 and the measurement part 6 may be an integral apparatus. The chelating agent determination system 1 may further include a mixing unit (corresponding to the slurry container 7 of the second embodiment) for mixing the incinerated ash that has been chelated with water to form a slurry. Further, the incineration ash may be subjected to a solidification treatment before the chelation treatment. In this case, it can be easily determined whether or not the solidification treatment has been sufficiently performed by measuring the presence or absence of the residual chelating agent. In addition, by quantifying the residual chelating agent, the amount of material necessary for the solidification treatment can be estimated.

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

  Moreover, in 1st and 2nd embodiment, the eluate accommodating part 3 may be a pipette or a syringe etc. which extract an eluate from a slurry via the filtration part 2. FIG. In this case, the filtration unit 2 may be a filter that is detachably attached to the eluate storage unit 3. Thereby, when the eluate container 3 extracts the eluate from the slurry, the filtration unit 2 is attached to the eluate container 3. Further, when the eluate is added from the eluate storage unit 3 to the mixing units 5 and 5 </ b> A, the filtration unit 2 is removed from the eluate storage unit 3.

  In the first and second embodiments, the chelating agent quantification method using the chelating agent quantification system may be performed automatically, partially automatically, or manually. It may be broken. That is, a part or all of the chelating agent quantification method described above may be performed by an operator, or a calculator or the like may be performed automatically.

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

  Moreover, in order to investigate whether soil is contaminated with heavy metals, you may implement the chelate determination method using the chelating agent determination system which concerns on this invention. That is, the measurement object may be soil that has not been subjected to heavy metal containment processing or the like. In this case, the residual chelating agent is quantified after performing a chelating treatment in which an appropriate amount of chelating agent is added to the soil that is the measurement object. Thereby, the degree of soil contamination by heavy metals can be estimated, and it can be easily determined whether or not heavy metal containment processing 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
The fly ash generated when the industrial waste was incinerated was collected, and a chelating agent having a predetermined concentration was added to the fly ash for chelation treatment. As the chelating agent, TS-300 piperazine chelating agent manufactured by Tosoh Corporation was used. 10 g of the fly ash after the chelation treatment was mixed in 100 ml of water (purified water) and stirred with a stirrer for 5 minutes, and then the water in which the fly ash was dispersed was filtered using a funnel and filter paper. The filter paper is manufactured by Advantech Toyo Co., Ltd., for qualitative analysis. 101 was used. A measurement sample was prepared by adding and mixing 0.12 ml of a 0.02 mol / L aqueous copper sulfate solution to the filtrate extracted by filtration.

  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 turbidimeter 500G manufactured by Kyoritsu Riken Co., Ltd. as a turbidimeter. The measurement wavelength of the turbidimeter was 660 nm, and the turbidity measurement range was 20 to 500 degrees. As for turbidity, 1 mg of formazine, which is a standard substance, was added to 1 L of purified water, and the turbidity of a uniformly dispersed suspension was defined as 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 chelating agent concentration was 0, and when the turbidity was 500 or more, the chelating agent concentration was not measurable.

  FIG. 4 is a graph showing the results of Table 1. In FIG. 4, the horizontal axis indicates the amount of chelating agent added, the left vertical axis indicates turbidity, and the right vertical axis indicates the concentration of the chelating agent in the measurement sample. The triangles 11a to 11e in FIG. 4 are the chelating agent concentrations, and the diamonds 12a to 12e in FIG. 4 are the turbidity of the measurement sample. As shown in Table 1, when the addition amount of the chelating agent is 0 wt% to 6 wt%, the turbidity hardly changes. Therefore, the inclination of the straight line 13 connecting the rhombuses 12b and 12c in FIG. 4 is very small. This is because the chelating agent added at the time of chelation sufficiently reacts with the heavy metal in the fly ash, and the chelating agent is not contained at all or almost in the measuring sample. Ion) and chelating agent do not react and water insoluble substances are not formed.

  On the other hand, as shown in Table 1, when the addition amount of the chelating agent is 7 wt% to 8 wt%, the turbidity increases rapidly. Therefore, the inclination of the straight line 14 connecting the rhombuses 12d and 12e in FIG. 4 is very large compared to the inclination of the straight line 13. This is because an excessive chelating agent is added during the chelation treatment, and the remaining chelating agent is contained in the measurement sample. Therefore, the copper ion in the measurement sample reacts with the remaining chelating agent and is insoluble in water ( This is probably because the copper complex) is formed and the turbidity of the sample to be measured increases rapidly. Since the measurement sample contains copper ions adjusted to a predetermined amount, the amount of copper complex formed varies depending on the concentration of the residual chelating agent. That is, the amount of change in turbidity of the measurement sample is determined by the concentration of the residual chelating agent. This shows that there is a correlation between the turbidity of the measurement sample and the concentration of the residual chelating agent.

  An intersection 15 of the straight lines 13 and 14 corresponds to a point at which a copper complex starts to be formed in the mixed solution. That is, the intersection 15 corresponds to a point where the heavy metal in the fly ash and the chelating agent just react in the chelation treatment. In other words, the intersection 15 is a point indicating a threshold 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 15 that is an appropriate amount of addition of the chelating agent in the chelation treatment can be easily obtained.

(Example 2)
The use of M-1 dithiocarbamic acid chelating agent manufactured by Miyoshi Oil & Fats Co., Ltd. as the chelating agent, the 5-fold dilution of the filtrate extracted by filtration, and a 0.04 mol / L nickel chloride aqueous solution in the diluted filtrate A measurement sample was prepared in the same manner as in Example 1 except that 0.6 ml of was added and mixed to prepare a measurement sample. 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 represents the amount of chelating agent added, the left vertical axis represents turbidity, and the right vertical axis represents the concentration of the chelating agent in the measurement sample. The triangles 21a to 21f in FIG. 5 are the chelating agent concentrations, and the diamonds 22a to 22f in FIG. 5 are the turbidity of the measurement sample. As shown in Table 2, when the addition amount of the chelating agent is 0 wt% to 6 wt%, the turbidity hardly changes. Therefore, the inclination of the straight line 23 connecting the rhombuses 22b and 22c in FIG. 5 is very small. This is because, as explained in Example 1, the chelating agent added at the time of chelation 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 addition amount of the chelating agent is 7 wt% to 9 wt%, the turbidity is significantly increased. Therefore, the inclination of the straight line 24 that connects the rhombuses 22d to 22f in FIG. 5 is larger than the inclination of the straight line 23. This is considered to be because nickel ions in the measurement sample reacted with the residual chelating agent to form a water-insoluble substance (nickel complex) as described in Example 1. Since the measurement sample contains nickel ions adjusted to a predetermined amount, the amount of nickel complex formed varies depending on the concentration of the residual chelating agent. Therefore, also in Example 2, it turns out that there is a correlation between the turbidity of the measurement sample and the concentration of the residual chelating agent. In addition, the increase rate of the turbidity of the solution with respect to the amount of the residual chelating agent in Example 2 is larger than that in Example 1.

  An intersection 25 of the straight lines 23 and 24 corresponds to a point at which a nickel complex starts to be formed in the mixed solution. That is, the intersection 25 corresponds to a point where the heavy metal in the fly ash and the chelating agent just react in the chelation treatment. Therefore, also in Example 2, by obtaining the straight lines 23 and 24, it is possible to easily obtain the intersection point 25 that is an appropriate addition amount of the chelating agent in the chelation treatment.

  DESCRIPTION OF SYMBOLS 1 ... Chelating agent fixed_quantity | quantitative_assay system, 2 ... Filtration part, 3 ... Eluate accommodating part, 4 ... Metal ion accommodating part, 5 ... Mixing part, 6 ... Measuring part.

Claims (8)

Forming a solution by mixing the measurement object subjected to chelation treatment into water and then removing the measurement object;
Adding a predetermined amount of metal ions to the solution;
Quantifying a chelating agent in the solution based on measurement of turbidity of the solution to which the metal ions have been added;
A chelating agent determination method comprising: A step of forming a solution by mixing the incinerated ash that has been chelated with water, and then removing the incinerated ash;
Adding a predetermined amount of metal ions to the solution;
Quantifying a chelating agent in the solution based on measurement of turbidity of the solution to which the metal ions have been added;
A chelating agent determination method comprising:   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 chelating agent.   The method for quantifying a chelating agent according to claim 1 or 2, wherein the metal ion is nickel ion, and the chelating agent is a dithiocarbamic acid 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 for filtering a slurry in which a measurement object including a heavy metal insolubilized by a chelating agent is dispersed;
A mixing unit for mixing a predetermined amount of metal ions into the eluate eluted by the filtration unit;
A measurement unit for measuring the turbidity of a mixture obtained by mixing the eluate and the metal ions;
From the turbidity of the mixed solution obtained by the measuring unit, a quantitative unit for quantifying the chelating agent in the mixed solution,
A chelating agent determination system comprising: A filtration unit for filtering the slurry in which the incinerated ash containing the heavy metal insolubilized by the chelating agent is dispersed;
A mixing unit for mixing a predetermined amount of metal ions into the eluate eluted by the filtration unit;
A measurement unit for measuring the turbidity of a mixture obtained by mixing the eluate and the metal ions;
From the turbidity of the mixed solution obtained by the measuring unit, a quantitative unit for quantifying the chelating agent in the mixed solution,
A chelating agent determination system comprising:   A method for quantifying a chelating agent, comprising adding a predetermined amount of metal ions to a solution and then measuring the turbidity of the solution to quantify the chelating agent in the solution.

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