JP2019209250A - Treatment agent for incineration ash, and treatment method of incineration ash - Google Patents

Abstract

To provide a new treatment agent and a treatment method, capable of performing decontamination of incineration ash, and a proper treatment of contamination caused by a heavy metal near a disposal field.SOLUTION: A treatment agent for incineration ash includes sulfuric acid, sodium perchlorate, a flocculant for heavy metals, and a surface treatment agent. Especially, when assuming that the whole treatment agent for incineration ash is 100 wt%, the treatment agent contains water, 10-20 wt% sulfuric acid, 30-40 wt% sodium perchlorate, 10-25 wt% polyferric sulfate as the flocculant, and 15-35 wt% ferric nitrate or sodium nitrate as the surface treatment agent.SELECTED DRAWING: Figure 1

Description

The present invention relates to a treatment agent for incineration ash and a method for treating incineration ash.

Patent Documents 1 and 2 have already been proposed as means for detoxifying heavy metal ions contained in incineration ash such as garbage and heavy metal soil.

What is shown in Patent Document 1 includes (A) sulfuric acid, and (B) at least one of aluminum sulfate and polyaluminum sulfate as the main agent, (C) at least one of ferric sulfate and ferric chloride, (E) an aqueous solution containing at least one of ferric sulfate, (F) magnesium chloride, and magnesium sulfate; (D) at least one of potassium silicate and sodium silicate as a concomitant agent; and (G) a barium ferrite magnet. , At least one of sodium aluminate and sodium hexametaphosphate, and (H) an aqueous solution in which sodium polyacrylate is blended. The weight blending ratio in the main agent is 100 to 250 for water, and the above A is 2 to 5, B is 250 to 600, C is 80 to 250, E is 10 to 50, F is 5 to 10, and the weight ratio in the combination agent is water. 100-300, the above D is 500 to 1000, the G is 50 to 150, an inorganic electrolyte coagulant that can detoxify heavy metal ions the H is 2 to 5 (claim 1).

Further, in claim 2 of Patent Document 1, the inorganic electrolytic coagulant according to claim 1 is used, and first, the main agent is mixed with the object to be treated, and then the combination agent is further added. A resource recycling method using an inorganic electrolytic coagulant that can block heavy metal ions in a processing object by mixing is shown.
The invention disclosed in Patent Document 1 is based on the geological balance of elements, can be used to permanently block harmful heavy metals, and can be used as a resource, and an inorganic electrolytic coagulant and a resource using the same The present invention provides a processing method.

Patent Document 2 shows at least one of polyferric sulfate and ferric chloride, at least one of sodium nitrate (sodium nitrate) and calcium nitrate, ferric nitrate, and strong acid. And a treatment agent for purification of radioactive nuclide-contaminated soil, various radioactive contaminated fly ash and heavy metal-contaminated soil (Claim 1), and in claim 2, polyferric sulfate and ferric chloride 35 to 50 parts by mass, ferric nitrate 11 to 30 parts by mass, sulfuric acid 0.75 to 3 parts by mass, sodium nitrate 5.6 to 11.2 parts by mass, and calcium nitrate The processing agent for purification | cleaning with respect to the radionuclide contaminated soil containing various 5.6-11.2 mass parts, radioactive nuclide contaminated fly ash, and heavy metal contaminated soil is shown.

Further, in claim 3 of Patent Document 2, a pretreatment agent containing at least one of ferric nitrate and sodium nitrate and a strong acid, and the purification treatment agent according to claim 1 or 2. And a two-component cleaning function agent for radionuclide-contaminated soil, various radioactively contaminated fly ash and heavy metal-contaminated soil, characterized in that The pretreatment agent containing at least one of -20 parts by mass and 5.6-11.2 parts by mass of sodium nitrate and 30-37.5 parts by mass of sulfuric acid, and the purification according to claim 2. A two-component cleaning function agent for radionuclide-contaminated soil, various radiation-contaminated fly ash, and heavy metal-contaminated soil, which is characterized by combining a treatment agent for water, is shown.

Further, Claim 5 of Patent Document 2 is a method for cleaning radionuclide-contaminated soil using the cleaning function agent according to Claim 4, which includes the sulfuric acid and the ferric nitrate essential. A first stirring step of mixing and stirring a pretreatment agent, soil contaminated with radionuclides and water as a primary treatment object, and the primary treatment object after the first stirring step substantially into a solid phase and a liquid phase A first solid-liquid separation step for solid-liquid separation, and a second stirring step for mixing and stirring the purification agent containing the ferric polysulfate essential, the solid phase, and water as a secondary treatment object, And a second solid-liquid separation step for substantially solid-liquid separation of the secondary workpiece after the first stirring step into a solid phase and a liquid phase, and obtained by the second solid-liquid separation step A method of cleaning radionuclide contaminated soil, characterized in that the solid phase is washed soil, In claim 6, the inorganic binder aqueous solution containing sodium polyacrylate and sodium silicate, and the purifying treatment agent according to claim 1 or 2, wherein the polyferric sulfate is contained. When,
A two-part spill-out prevention agent for radionuclide-contaminated soil, various radiation-contaminated fly ash and heavy metal-contaminated soil, characterized in that

Further, claim 7 of Patent Document 2 includes an inorganic binder aqueous solution containing 0.2 to 0.5 parts by mass of sodium polyacrylate and 20 to 40 parts by mass of sodium silicate, and the purification according to claim 2. A two-component anti-scattering agent for radioactive nuclides contaminated soil, various radiation-contaminated fly ash and heavy metal-contaminated soil, characterized in that it is a combination of a treatment agent for use with ferric sulfate. Further, in claim 8, an inorganic binder aqueous solution containing a purifying treatment agent containing polyferric sulfate, ferric nitrate, and a strong acid, sodium polyacrylate, and sodium silicate. And a first spraying step of spraying the aqueous binder solution onto the radionuclide contaminated area, and a first spraying process. Second spraying step and processing method radionuclide contaminated sites performing for spraying said cleaning treatment agent to said radionuclide contaminated sites passed through the degree is shown.

Further, claim 9 of Patent Document 2 contains 35-50 parts by mass of polyferric sulfate, 11-30 parts by mass of ferric nitrate, and 0.75-3 parts by mass of sulfuric acid. A radionuclide-contaminated site using a two-part scattering spill inhibitor combining a treating agent for purification and an inorganic binder aqueous solution containing sodium polyacrylate and sodium silicate, Radionuclide-contaminated land treatment in which a first spraying step of spraying the binder aqueous solution to a radionuclide-contaminated site and a second spraying step of spraying the purification treatment agent to the radionuclide-contaminated site through the first spraying step The method shows.
The invention disclosed in Patent Document 2 is mainly for soil contaminated with radioactive nuclides generated in the nuclear accident, and moreover effective cleaning treatment for soil contaminated with heavy metals and the like caused by tsunami-affected sea mud. It is intended to provide a treating agent and a treating method for dealing with contaminated soil.

On the other hand, the actual situation of incineration ash treatment and final disposal site is as follows.
Leachate is constantly generated from the general waste management-type final disposal site specified in the ordinance. At the same time, hazardous wastes such as heavy metals are also contained in daily wastewater at the disposal site, so there are many associated water pathways and bottom mud contamination leading to estuaries and lakes. There are concerns about pollution.
Local residents are concerned about the above situation and there is a serious opposition movement in the establishment of a new disposal site, so it is impossible to secure a new disposal site. In reality, however, the existing disposal sites are depleted nationwide, and each local government is in a state of extreme difficulty in dealing with incineration ash.

While the proposals of Patent Documents 1 and 2 have been made, with respect to the current treatment method, treatment with slaked lime or a chelating agent has become mainstream for hearth ash and fly ash discharged from the incineration plant. Hazardous substances such as heavy metals are buried in the incineration ash, but the insolubilizing ability is not limited to slaked lime, and the chelating treatment can be temporarily surpassed for up to 2-3 weeks. Not too much.
As a result, the buried incineration ash is exposed to acid rain for a long time, and heavy metals continue to flow out of the disposal site for a long time and continue to pollute the bottom mud of the related water path.

Japanese Patent No. 4309464 Japanese Patent No. 5911716

The present invention provides a new treatment agent and a treatment method capable of appropriately treating decontamination of incineration ash and contamination by heavy metals in the vicinity of the disposal site, and eliminates the concerns of neighboring residents.
In addition, the present invention provides a treatment agent and a treatment method suitable for pretreatment (pre-treatment) of the means shown in Patent Documents 1 and 2, and intends to utilize the means shown in Patent Documents 1 and 2 more effectively. But there is.

The present invention provides an incineration ash treatment agent comprising sulfuric acid, sodium perchlorate, heavy metal flocculants, and a surface treatment agent.
The incineration ash includes fly ash and hearth ash from the incineration disposal site.
Further, the present invention provides the entire treatment agent for incineration ash as 100% by weight, together with water, 10-20% by weight of the sulfuric acid, 30-40% by weight of the sodium perchlorate, and polysulfuric acid as the flocculant. A treatment agent for incinerated ash containing 10 to 25% by weight of iron and 15 to 35% by weight of ferric nitrate or sodium nitrate as the surface treatment agent could be provided.
Furthermore, the present invention provides the entire treatment agent for incineration ash as 100% by weight, together with water, 10-20% by weight of the sulfuric acid, 30-40% by weight of the sodium perchlorate, and ferric nitrate as the flocculant. Alternatively, a treatment agent for incinerated ash containing 20 to 35% by weight of sodium perchlorate and 15 to 35% by weight of ferric nitrate or sodium nitrate as the surface treatment agent can be provided.
Furthermore, the present invention can provide a treatment agent for incinerated ash containing water, the sulfuric acid, the sodium perchlorate, the ferric polysulfate as the flocculant, and the ferric nitrate as the surface treatment agent. It was.
Still further, the present invention provides a step 1 for removing debris from the incineration ash, the incineration ash after the removal of the debris, and a treatment agent for the incineration ash, which are added to washing water and agitated to obtain the incineration ash. Step 2 of decontaminating the incinerated ash by transferring the adsorbed and immobilized group of the contaminant to be retained to a water-soluble state or an exchange state that is easily soluble in the washing water and eluting the contaminant in the washing water; A step of clarifying the contaminated water by administering a polymer flocculant to the washing water which has become contaminated water and separating and recovering the pollutant as an agglomerated block; and the incinerated ash or decontamination after decontamination The processing method of the incineration ash using the said processing agent of incineration ash which performs step 4 which carries out natural dehydration or forced dehydration of ash was able to be provided.
The incineration ash includes incineration ash that has not been chelated in addition to incineration ash that has been chelated. Accordingly, the adsorbed and immobilized group of the pollutant includes not only the chelating agent of the incinerated ash that has been chelated, but also those possessed by elements other than the chelating agent in the incinerated ash.
Furthermore, the present invention removes debris in the incineration ash by passing the incineration ash through a sieving machine in the step 1, and in the step 2, the washing water is water, The same amount of water as that of the water is added to the water to form a slurryed slurry, and 3 to 5% by weight of the treatment agent is added to the slurryed water with respect to 100% by weight of the slurryed water. Step 22 and adjusting the slurryed water after the treatment agent to be strongly acidic and stirring it for a predetermined time with a stirrer to elute the pollutants in the incinerated ash into the slurryed water. Step 23 is carried out by allowing it to stand still for a period of time. In Step 3, the ferric sulfate 0.02 to 0.03 per 100% by weight of the contaminated water which is the supernatant liquid separated in the precipitation. Step 3 for loading weight% And 0.04 to 0.06% by weight of the polymer flocculant which is a liquid whose pH is adjusted to be almost neutral with respect to 100% by weight of the contaminated water before the execution of Step 31 which is the supernatant liquid separated by the precipitation. The step 32 is performed to clarify the contaminated water by separating and recovering the aggregated block that has been agglomerated by stirring with a stirrer for a predetermined time, and in step 4, the precipitate is the precipitate. 6. The method for treating incinerated ash according to claim 5, wherein the decontaminated ash is subjected to natural dehydration or forced dehydration.
In the step 4, the decontaminated ash is forcibly dehydrated by performing mechanical dehydration in a dehydrator, and the contaminated water that has been clarified by removing the aggregation block in the step 32; It was possible to provide a method for treating incinerated ash in which each of the water separated from the decontaminated ash by the dehydration in Step 4 was reused as the wash water in Step 2.

In the present invention, a predetermined amount of fly ash and hearth ash is introduced into the washing water, and the mixture is slurried by stirring. After the pH is adjusted by adding a predetermined amount of the treatment agent according to the present invention, By performing dyeing and stirring, the dithiocarbamine group (adsorbing group) constructed by the chelating agent can be destroyed, and the mainly heavy metal ions that have been restrained can be eluted in the washing water in a short time.
By carrying out the present invention, the same effects as described above can be obtained for untreated incinerated ash that has not been chelated with a chelating agent. That is, the untreated incinerated ash that has not been chelated can be eluted into the wash water in a short time by the implementation of the present invention. It is removed and the incineration ash can be made safe and harmless treated ash.

Explanatory drawing which shows the whole flow about one Embodiment of the processing method which concerns on this invention. (A) And (B) is explanatory drawing which shows the molecular structure of the adsorption fixed group of incineration ash.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Summary of properties of incineration ash)
Incineration ash is made up of “solid phase, gas phase, and liquid phase”. Contaminants such as heavy metal ions are in a fixed state that is hardly soluble in water and easily ionized in a water-soluble and exchanged state in water. Adsorbed and retained.
The 1: 1 type unit layer shown in FIG. 2A is bonded to the Al octahedron sheet so that the Si tetrahedron sheet pierces. In the 2: 1 type unit layer shown in FIG. 2B, two Si tetrahedron sheets are bonded in such a manner that the Al octahedron sheet is sandwiched (sandwiched) from both sides (up and down in the figure).
Incineration ash is usually classified into fly ash and hearth ash. Fly ash retains an overwhelmingly large number of adsorbed and fixed groups of alumina octahedron and silicon tetrahedron as compared with hearth ash, so the contamination concentration is also extremely high.
The excellent decontamination is determined by how many fixed states can be transferred to a water-soluble or exchanged state.

(Inorganic electrolysis / decontamination insolubilization by the treatment agent according to the present invention)
Next, inorganic electrolysis / decontamination insolubilization will be described.
The treatment agent according to the present invention is a compound in which several kinds of metal positively charged substances having different ionic valences are synthesized and mixed in a single solvent liquid mainly composed of sodium perchlorate, and cannot be achieved with a single valence. An iron-containing decontamination agent that takes into account multiple synergistic effects such as neutralization reaction and catalytic reaction.
When the treatment agent according to the present invention is added to the laundered washing water, a rapid hydration reaction occurs, a hydroxide composed of several valences is generated, and an ion increase peculiar to inorganics occurs.
Each generated ion plays a characteristic role. In other words, neutralization of heavy metal ions, etc., restrained by adsorption fixed groups held by incineration ash and adsorption fixed groups (dithiocarbamic acid groups) built with chelating agents, water-soluble or exchanged fixed ions that are hardly soluble in water Transition to the state, and elution into the cleaning solution is realized. Contaminants can be separated and recovered by subjecting the contaminated water eluted above to a coagulation treatment.
In the natural world, heavy metals are usually strongly adsorbed and fixed on fixing groups (bonding groups) in minerals in an ionized state.

By the above treatment, around 60% of the heavy metal ions existing in the fixed state are transferred to the water-soluble / exchanged state, which is easily soluble in water, and it is removed. Eluted.
In addition, the remaining trace contaminants have been confirmed to be permanently undissolved as a result of a 500-year elution test based on the guidelines of the Soil Environment Center (4-5 Kashimachi, Chiyoda-ku, Tokyo, KS Building, 3F). , NPO Japan Geological Contamination Examination Organization (Rose Heights 1-24, Makuhari-Hongo, 5-chome, Hanamigawa-ku, Chiba-shi), Insolubilization Examination Committee, Medical Geological Research Institute Co., Ltd. (Inage-ku, Chiba City, Chiba Prefecture) Requested the insolubilization test and its judgment by 22) at 397 Sannomachi, and added three types of dissolution tests as indicated by the jury. As a result, all tests were judged to be appropriate as soil dissolution tests. .
Proposed by the Study Group on Stability of Heavy Metal Insolubilized Soil at the Soil Environment Center (http://www.gepc.or.jp/) with the Ministry of the Environment as the competent government This is based on the test method that was conducted (summary report of the examination results of 2001-2005). That is, the 500 years elution test described above is a test conducted in accordance with the conditions of the elution test for evaluating the long-term stability against the pH change of the heavy metal insolubilized soil set in the subcommittee.
Specifically, in the case where the insolubilized soil is exposed to acid, the above-mentioned group assumes acid rain, acid rain is pH 4.0, annual rainfall is 2,000 mm, and soil is 1 m × 1 m × 1 m = 1. The case of exposure to this acid rain for 100 years was assumed as a legitimate meter, 1.3 ton dry soil / legislation meter. The acid amount per unit dry soil is 15.4 meq / kg dry soil.
An acid addition elution test method I was conducted by adding an acid amount corresponding to this and eluting it in the same procedure as the dissolution test of No. 46 of the Environment Agency in 1991 (hereinafter referred to as No. 46 dissolution test). The eluate (solvent) used in the test is [H +] = 1.54 meq / L (pH 2.8 in the case of sulfuric acid).
And what added the acid amount equivalent to 500 years was made into acid addition elution test method II (76.9 meq / kg dry soil). The eluent (solvent) is [H +] = 7.69 meq / L (pH 2.1 in the case of sulfuric acid). If the soil is 1 m × 1 m × 2 m = 2 cubic meters, the acid addition elution test method I corresponds to the acid amount for 200 years, and the acid addition elution test method II corresponds to the acid amount for 1000 years. Become. About 500 years of said elution tests over time, as described above, an acid amount corresponding to 500 years is added.

(Basic configuration of treatment agent according to the present invention)
The present invention provides an incineration ash treatment agent comprising sulfuric acid, sodium perchlorate, heavy metal flocculants, and a surface treatment agent.
In particular, in this example, the entire treatment agent for incineration ash is 100% by weight, together with water, the sulfuric acid is 10 to 20% by weight, the sodium perchlorate is 30 to 40% by weight, and the polysulfuric acid is used as the flocculant. An incineration ash treatment agent containing 10 to 25% by weight of iron and 15 to 35% by weight of ferric nitrate or sodium nitrate as the surface treatment agent is provided.
About the said processing agent, it demonstrates in detail focusing on the characteristic and objective of each compounding component (structure of a synthetic chemical), and a compounding ratio.

(1) Sulfuric acid sulfuric acid is used to stabilize the treatment agent (synthetic chemical). The total amount of the processing agent is 100% by weight, and the blending ratio of sulfuric acid in the processing agent is in the range of 10 to 20%, preferably 10%.

(2) Sodium perchlorate Sodium perchlorate has a strong oxidizing power and a strong corrosion performance of metals. For this reason, sodium perchlorate is used as a corrosive agent.
The total treatment agent is 100% by weight, and the blending ratio of sodium perchlorate in the treatment agent is in the range of 30 to 40% by weight, preferably 40% by weight.

(3) Ferric polysulfate Polyferric sulfate has the ability to agglomerate heavy metals and has a capacity of up to 2 degrees below zero. For this reason, polyferric sulfate is used as an aggregating agent for heavy metals.
Polyferric sulfate also eliminates the bad smell of hydrogen sulfide. Therefore, polyferric sulfate is also used as a deodorant.
The total amount of the processing agent is 100% by weight, and the ferric sulfate in the processing agent is in the range of 10 to 25% by weight, preferably 15% by weight.
Further, in place of the polyferric sulfate, 20 to 35% by weight of ferric nitrate or sodium perchlorate can be used in 100% by weight of the whole treatment agent.

(4) Ferric nitrate Ferric nitrate is excellent in the corrosive ability of metals and is used as a metal surface treatment and an oxidizing agent.
Ferric nitrate has the ability to adsorb radioactive substances which are heavy metal ions only among 3599 chemicals.
The total amount of the processing agent is 100% by weight, and ferric nitrate in the processing agent is in the range of 15 to 35% by weight, preferably 20% by weight.
Moreover, it replaces with the said ferric nitrate and sodium nitrate can be used in 15 to 35 weight% in 100 weight% of the whole processing agent.

(5) The remaining component other than the above (1) to (4) is 100% by weight of the water treatment agent. Use fresh water as water.

(Incineration ash treatment method according to the present invention)
Hereinafter, the flowchart of the processing method of incineration ash concerning the present invention is explained.
In the incinerated ash treatment method according to the present invention, the following steps 1 to 6 are performed (FIG. 1).

(Step 1)
Step 1 is a debris removal step for removing debris in the hearth ash.
In step 1, the incineration ash is passed through a sieving machine to remove debris in the incineration ash.

(Step 2)
Step 2 is a pollutant elution process in which the adsorbed and fixed groups of pollutants held by the chelating agent and incinerated ash are transferred to a water-soluble / exchanged state that is easily soluble in water and are eluted into the wash water. .
Specifically, in step 2, each of the following steps 21 to 23 is performed.

(1) In step 21, the incinerated ash having passed through step 1 is put into a washing stirrer.
That is, in step 21, washing water is used as water, and the incineration ash is put into a washing stirrer having the same weight as that of the water, and stirred to obtain mudified water in a mud state.

(2) In step 22, 3 to 5% by weight of the treatment agent is added to the slurryed water with respect to 100% by weight of the slurryed water in step 21 (the entire slurryed water is 103 to 105% by weight). Become).

(3) In step 23, the contaminated water in the incinerated ash is converted into the slurry water by adjusting the slurry water after the treatment agent to be strongly acidic and stirring it with a washing stirrer for a predetermined time. Elute. After stirring, the mixture is allowed to stand for a predetermined time for precipitation.
In this example, the slurryed water after the treatment agent is charged is adjusted to pH 1.5, stirred for 20 minutes with a washing stirrer, and then a precipitate is generated by standing still for 20 minutes (stopping stirring). In addition, about the point which adjusts the said muddy water after processing agent addition to pH1.5, it adjusts to pH1.5 by adding diluted sulfuric acid to the said muddy water.

(Step 3)
Step 3 is a clarification process of contaminated water. In Step 3, clarification of contaminated water accompanying cleaning of incineration ash and the like is attempted.
Specifically, in step 3, the following processes of step 31 and step 32 are performed.

(1) In step 31, the strongly acidic washing contaminated water of the washing stirrer is transferred to the coagulation stirrer. Then, 0.02 to 0.03% by weight of ferric polysulfate is added to the agitation stirrer with respect to 100% by weight of the contaminated water which is the supernatant liquid separated by precipitation (the entire contaminated water after the addition). Of 100.02 to 100.03% by weight).

(2) In step 32, 0.04 to 0.06% by weight of the polymer flocculant, which is a liquid whose pH is adjusted to be substantially neutral, that is, pH 7.0, is added to the contaminated water before the addition of polyferric sulfate in step 31. 100% by weight and stirred for a predetermined time with a coagulant stirrer (the total weight of the contaminated water after adding ferric sulfate in Step 31 and the polymer coagulant in Step 32 is 100.06 to 100.09%) %).
In this example, in step 32, the agitation stirrer is used for 15 minutes. By the stirring, the contaminated water becomes clarified water. That is, the contaminants such as heavy metals are separated and recovered as agglomerated blocks by the treatment in step 3, and the contaminated water remaining by separating and recovering the agglomerated blocks aggregated by the stirring is clarified clarified water. It becomes.
As the polymer flocculant which is a liquid adjusted to pH 7.0, polyferric sulfate can be employed. As the polymer flocculant, ferric nitrate or sodium perchlorate can be employed in addition to ferric sulfate.
The above agglomerated blocks are rapidly solidified by adding a small amount of cement and sodium silicate (water glass) to form a solidified glass that does not elute pollutants, and are processed at a general control-type final disposal site (control-type final) Fill in the disposal site).

In step 4, the decontamination ash that is the precipitate obtained in step 2 is naturally dehydrated or forcedly dehydrated. In this example, in step 4, the decontaminated ash is forcibly dehydrated by performing mechanical dehydration with a dehydrator. However, it may be naturally dehydrated by natural drying.
On the other hand, decontaminated ash after dehydration is disposed at a disposal site or utilized as a resource.

In step 5, the clarified water obtained in step 3 is transferred to a storage tank (clarified water storage tank).
In Step 6, the moisture obtained by the mechanical dehydration in Step 4 is transferred to a storage tank (dehydration storage tank).

The clarified water in the clarified water storage tank and the water in the dewatered storage tank are transferred to the washing stirrer as recycled water. The recycled water transferred is reused as the washing water in step 2 by the washing stirrer.

As described above, around 80% of the contaminants such as heavy metals are removed by the decontamination treatment using the treatment agent according to the present invention, and the remaining trace contaminants are oxidatively fixed. The verification of the permanent insolubilization capability is based on the aforementioned report on the results of the insolubilization review committee of the NPO Japan Geological Contamination Examination Organization and the Medical Geological Research Institute, Inc. (Table 2 below).

(Main uses of the treatment agent according to the present invention)
1) This agent quickly destroys the adsorbed immobilization group (dithiocarbamic acid group) constructed with a chelating agent, neutralizes the immobilization group held by the incineration ash, neutralizes the water-soluble group, and moves to the water-soluble / exchanged state. And elute in wash water.
2) This agent can be used as a pretreatment agent in Patent Nos. 4309464 and 5911716 to improve the treatment system.
3) This agent can be used for decontamination treatment of sea mud and land contaminated soil.

Table 1 shows examples of the invention. In addition, an Example is an illustration and is not used for interpreting this invention restrictively.

Table 2 shows the results of soil analysis (list of soil analysis results of backfill confirmation survey).
In the above result report (column of the amount of second-class specific hazardous substance elution in Table 2), the hearth ash is the lower limit of quantification in all items (column of second-class heavy metals etc. in the soil contamination criteria shown in Table 3) It was confirmed that it was below.

Tables 4 to 8 show the evaluation results of insolubilization tests of heavy metals in refuse incineration ash using the treatment agent according to the present invention. The waste incineration ash used in the test is Chiba ash, the fly ash from the A waste incineration site, the hearth ash from the A waste incineration site, the fly ash from the B waste incineration site, and the hearth ash from the B waste incineration site There are five types.
The Chiba ash in Table 4 is fly ash collected from a disposal site in Chiba City in September 2016. “Before treatment” in Table 4 shows the result of a test conducted on the collected fly ash in September 2016 before the treatment with the treatment agent according to the present invention. “Results after treatment” in Table 4 shows test results in December 2017 in which the collected fly ash was treated with the treatment agent according to the present invention.
The insolubilization test for incineration ash from each waste incineration plant was conducted by Medical Geological Research Institute. The treatment test of the insolubilization test was performed by a method developed by both Kayohiko Tanimoto and Yukio Yanagimoto, inventors of Japanese Patent No. 4309464 (Patent Document 1). And, for the final material obtained by the insolubilization test, Medical Geological Research Institute Co., Ltd. has 4 types in total, 3 types proposed by the NPO Japan Geological Contamination Inspection Organization Insolubilization Test Review Committee and 1 type of Soil Environment Center. A kind of evaluation was performed. The dissolution test methods are as follows.
(The above four types of dissolution test conducted by Medical Geological Research Institute)
1) Method X-1: Sulfuric acid and nitric acid mixed aqueous solution addition elution test method (pH 2.8)
(Proposal I of the NPO Japan Geological Pollution Examination Organization, 2015)
2) Method X-2: Repeated dissolution test method by adding sulfuric acid / nitric acid mixed aqueous solution (twice) (pH 3.1)
(Proposal II of NPO Japan Geological Pollution and Examination Organization, 2015)
3) Method X-3: Repeated elution test method by adding sulfuric acid / nitric acid mixed aqueous solution (5 times) (pH 3.5)
(Proposal III of NPO Japan Geological Pollution Examination Organization III, 2015)
4) Method Y: Sulfuric acid addition dissolution test method I (pH 2.8) (Soil Environment Center, 2006)

The method X-1 of the above 1) is a flow of the incinerated ash treatment method according to the present invention described above, wherein dilute sulfuric acid is added to the muddy water after the treatment agent is charged in step 23 of step 2 to pH 1.5. The sample (1 point) was obtained by diluting the slurryed water with a mixed aqueous solution of sulfuric acid and nitric acid to adjust the pH to 2.8. Other points differ from the above step 2 There is no point (Fig. 1).
In the method X-2 of 2) above, in the above-described flowchart of the method for treating incineration ash according to the present invention, dilute sulfuric acid is added to the muddy water after the treatment agent is charged in step 23 of step 2, and the pH is 1.5. In terms of the points to be adjusted, 2 samples (twice) were obtained by diluting the slurryed water with a mixed aqueous solution of sulfuric acid and nitric acid to obtain pH 3.1. There is no difference from step 2 (FIG. 1).
The method X-3 of the above 3) is a flow of the incinerated ash treatment method according to the present invention described above, wherein dilute sulfuric acid is added to the muddy water after the treatment agent is charged in step 23 of step 2 to pH 1.5. 5 points (5 times) were obtained by changing the sludge water to pH 3.5 by diluting the slurry water with a mixed aqueous solution of sulfuric acid and nitric acid. There is no difference from step 2 (FIG. 1).
Method Y of 4) above is adjusted to pH 1.5 by adding dilute sulfuric acid to the muddy water after the treatment agent is charged in Step 23 of Step 2 in the flowchart of the method for treating incinerated ash according to the present invention described above. In this regard, a sample (1 point) was obtained by diluting the slurryed water with sulfuric acid to a pH of 2.8, and there were no differences from step 2 in other matters (FIG. 1). .

In addition, the analysis value of the final freight was requested to be evaluated by a third party NPO Japan Geological Contamination Inspection Organization Insolubilization Examination Committee and cross-checked. The NPO Japan Geological Contamination Examination Insolubilization Examination Review Committee conducted a total of 6 types: 4 types proposed by the committee and 2 types of Soil Environment Center. The dissolution test methods are as follows.
(The above six dissolution test methods conducted by the NPO Japan Geological Contamination Examination Insolubility Examination Committee)
5) Method I: Sulfuric acid aqueous solution elution test method (pH 2.8) / Soil Environment Center proposal 6) Method II: Sulfuric acid aqueous solution elution test method (pH 2.1) / Soil Environment Center proposal 7) Method III: Sulfuric acid / Nitric acid Mixed aqueous solution addition dissolution test method (pH 2.8)
8) Method IV: Repeated dissolution test method (pH 3.1) by adding a mixed solution of sulfuric acid and nitric acid
9) Method V: Method of adding and dissolving sulfuric acid / nitric acid aqueous solution (pH 2.1)
10) Method VI: Sulfuric acid / nitric acid / NaCl mixed aqueous solution addition elution test method (pH 2.8)

Method I of 5) above is adjusted to pH 1.5 by adding dilute sulfuric acid to the muddy water after the treatment agent is charged in Step 23 of Step 2 in the flowchart of the method for treating incinerated ash according to the present invention described above. In this regard, a sample (one point) was obtained by diluting the slurry water with a sulfuric acid aqueous solution to a pH of 2.8, and there were no differences from Step 2 in other matters (FIG. 1). ).
Method II of 6) above is adjusted to pH 1.5 by adding dilute sulfuric acid to the muddy water after the treatment agent is charged in Step 23 of Step 2 in the flowchart of the incineration ash treatment method according to the present invention described above. In this regard, a sample (1 point) was obtained by diluting the slurryed water with a sulfuric acid aqueous solution to pH 2.1, and there were no differences from Step 2 in other matters (FIG. 1). ).
Method III of the above 7) is adjusted to pH 1.5 by adding dilute sulfuric acid to the muddy water after the treatment agent is charged in Step 23 of Step 2 in the flowchart of the incineration ash treatment method according to the present invention described above. The sample (1 point) was obtained by diluting the slurry water with sulfuric acid / nitric acid mixed aqueous solution to pH 2.8, and there is no difference from the above step 2 in other matters. (FIG. 1).
Method IV of 8) above is adjusted to pH 1.5 by adding dilute sulfuric acid to the muddy water after the treatment agent is charged in Step 23 of Step 2 in the flowchart of the incineration ash treatment method according to the present invention described above. In this regard, 5 samples were obtained by diluting the slurry water with a sulfuric acid / nitric acid mixed aqueous solution to obtain pH 3.1, and there were no differences from the above step 2 in other matters (FIG. 1).
The method V of 9) above is adjusted to pH 1.5 by adding dilute sulfuric acid to the muddy water after the treatment agent is charged in step 23 of step 2 in the flowchart of the method for treating incinerated ash according to the present invention described above. In this regard, a sample (1 point) was obtained by diluting the slurry water with a sulfuric acid / nitric acid mixed aqueous solution to pH 2.1, and there are no differences from Step 2 above in other matters. (FIG. 1).
Method VI of 10) above is adjusted to pH 1.5 by adding dilute sulfuric acid to the muddy water after the treatment agent is charged in Step 23 of Step 2 in the flowchart of the incineration ash treatment method according to the present invention described above. The sample (1 point) was obtained by diluting the slurry water with sulfuric acid / nitric acid / NaCl mixed aqueous solution to pH 2.8, and other points differed from step 2 above. No (Figure 1).
Although details are omitted, the results of the above 6) elution test methods of 5) to 10) conducted by the NPO Japan Geological Contamination Examination Organization Insolubility Examination Committee were also conducted by Medical Geological Research Institute, Inc. It was confirmed that the test results were almost the same as the results of the four types of dissolution test methods 1) to 4).

In Table 4 to Table 8 (concentration transition for each element), reference values (soil content standard, soil elution amount / groundwater environmental standard, soil) for each test item of the above-mentioned methods X-1, X-2, X-3, Y Those exceeding environmental standards are indicated by black triangles (▲). The soil environmental standards are those stipulated in Article 16, Paragraph 1 of the Environmental Basic Law. The standards for each hazardous substance are listed on the separate website of the Ministry of the Environment website (https://www.env.go.jp/kijun/dt1. html).
In Chiba ash (fly ash), before treatment, the leaching amount of cadmium residue (Y) (X-1), the leaching amount of hexavalent chromium raw ash (Y) (X-1), the raw lead The amount of ash soil elution (Y) (X-1) and the amount of fluorine residue soil elution (Y) (X-1) exceeded the standard values. It can be confirmed that the standard values and environmental standards (soil environmental standards) are met in all tests (Table 4).

In the hearth ash of the A disposal site, the amount of soil leaching of cadmium residues (Y) (X-1), the amount of soil leaching of hexavalent chromium raw ash (Y) (X-1), Soil content of raw ash, soil content of residue and soil elution amount (Y) (X-1), and soil elution amount of fluorine residue (X-1) exceeded the respective environmental standards. However, the final filtrate after the treatment conforms to the standard values for each item other than the amount of fluorine outflow (Y), and thus the effect of insolubilization can be sufficiently confirmed (Table 5).

The fly ash of the A disposal site did not satisfy the standard values for cadmium, total mercury, lead, and fluorine in this treatment (Table 6).
Specifically, in the fly ash of the A disposal site, the soil leaching amount of cadmium residue (Y) (X-1), the soil content of lead raw ash and the soil leaching amount (Y) (X -1) and the soil content of the residue and the soil elution amount (Y) (X-1), and the soil elution amount of the fluorine residue (Y) (X-1) exceeded each standard value. In addition, for the final filtrate after treatment, each test of cadmium and fluorine, the amount of soil elution of total mercury (Y), the first of (X-2) and the first of (X-3), the amount of elution of lead ( In the first and second times of (X-1) and (X-2), and the fourth and fifth times of (X-3), the reference values are exceeded (Table 6). In addition, regarding the final filtrate of total mercury after treatment, the second time of soil elution (X-1) and (X-3) is below the reference value (of soil elution), but the environment is "not detected" It does not meet the standards.
On the other hand, with regard to the final filtrate after the treatment of fly ash at the A disposal site, the second time of total mercury elution (X-2) and the third to fifth times of (X-3), the amount of lead elution ( In each of the first to third times of Y) and (X-3), it was below the reference value (of soil elution amount) or not detected (Table 6).
Unlike hearth ash, fly ash may contain highly volatile substances such as mercury, lead, and fluorine, which may be highly concentrated (Table 6).

In the hearth ash of B disposal site, soil leaching amount of cadmium ash (Y) (X-1) and soil leaching amount (Y) (X-1), lead ash soil before treatment Although the content and the amount of boron residue dissolved into the soil (Y) (X-1) exceeded the standard values, each final filtrate after treatment was treated with cadmium in the amount of soil eluted (X- Except for 1), it did not exceed the standard value. In addition, it can be confirmed that each final filtrate after treatment including cadmium meets the environmental standards of all tests (Table 7).

The fly ash at B disposal site did not satisfy the standard values for cadmium, selenium, lead and fluorine (Table 8).
Specifically, in the fly ash at the B disposal site, before treatment, the soil content of cadmium ash, the amount of soil runoff (Y) (X-1), and the amount of soil leaching (Y) (X-1) ), Soil content of lead ash and soil elution amount (Y) (X-1), residue soil content and elution amount on the way (Y) (X-1), soil elution amount of arsenic residue (Y ) (X-1), soil elution amount of fluorine raw ash (Y) (X-1), soil elution amount of residue (Y) (X-1), soil elution amount of boron residue (Y) ( X-1) exceeded the standard value, and in each test of cadmium and fluorine after treatment, the amount of selenium dissolved in soil (Y) (X-1), (X-2) First and (X-3) 1st to 4th, lead soil elution (Y) (X-1), (X-2) 1st and (X-3) 1st to 5th Value exceeded It has become a thing (Table 8). On the other hand, the second leaching amount of selenium (X-2) and the fifth time (X-3), the second soil leaching amount (X-2) after the treatment of fly ash at B disposal site, The arsenic and boron tests did not exceed the standards (Table 8).
Lead is about twice the reference value, and it can be seen that the effect is obtained from the concentration of the residue. Although fluorine is 10 times the reference value, it is 1/10 or less in view of the concentration of the residue, and the effect of the insolubilizer is considered to be large (Table 8).

In addition to the elution test on the final filtrate, the Medical Geological Research Institute Co., Ltd. conducted a soil elution test on the raw ash and residue obtained in the process of this insolubilization test (the method of the Soil Environment Center) The soil elution test (NPO Japan Geological Pollution Examination Organization 1) Method X-1 was conducted.

One sample for each incineration ash is used for each of the above elution tests, but Chiba ash and the like show high results such as satisfying the soil environment standard and the groundwater environment standard. In addition, the hearth ash at the A and B waste incineration sites has achieved high results with some elements removed. In addition, it has become clear from the evaluation of the Insolubilization Test Review Committee of the Medical Geological Research Institute and the NPO Japan Geological Contamination Examination Organization that even fly ash with relatively low results is recognized as being transferred to the liquid smoke.

The scientific basis of safety and harmlessness is based on the results of verification tests conducted by a wide range of people involved in the insolubilization review committee of the NPO Japan Geological Contamination Examination Organization and the Medical Geological Research Institute, Inc. On the other hand, the contaminated water eluted by the washing treatment is subjected to an agglomeration treatment and recovered by solid-liquid separation.
The treatment agent according to the present invention was confirmed to exhibit excellent ability under 10 kinds of scientific and academically strict verification verification.
By implementing the present invention, a decontamination / insolubilizing agent capable of fulfilling accountability to local residents can be provided as a treatment agent for the establishment of a new treatment plant that is becoming increasingly depleted.

Claims (7)

A treatment agent for incinerated ash containing sulfuric acid, sodium perchlorate, a heavy metal flocculant, and a surface treatment agent. The entire treatment agent for incineration ash is 100% by weight, together with water, 10-20% by weight of the sulfuric acid, 30-40% by weight of the sodium perchlorate, and 10-25 of polyferric sulfate as the flocculant. The treating agent for incinerated ash according to claim 1, comprising 15 to 35% by weight of ferric nitrate or sodium nitrate as the surface treating agent. 100% by weight of the entire treatment agent for incineration ash, together with water, 10-20% by weight of sulfuric acid, 30-40% by weight of sodium perchlorate, ferric nitrate or sodium perchlorate as the flocculant The processing agent for incineration ash according to claim 1, wherein the surface treatment agent contains 15 to 35% by weight of ferric nitrate or sodium nitrate. The incinerator ash treatment agent according to claim 1, comprising water, sulfuric acid, sodium perchlorate, polyferric sulfate as the flocculant, and ferric nitrate as the surface treatment agent. Step 1 for removing debris from incineration ash, the incineration ash after removal of debris, and the treatment agent for incineration ash according to any one of claims 1 to 4 are added to washing water and stirred. Step 2 of decontaminating the incinerated ash by transferring the adsorbed and immobilized group of the pollutant held by the incinerated ash to a water-soluble or exchanged state easily dissolved in washing water and eluting the pollutant in the washing water; , Step 3 of clarifying the contaminated water by administering a polymer flocculant to the washing water which has become contaminated water by the elution and separating and recovering the pollutant as an aggregate block, and the incineration after decontamination The processing method of incineration ash using the processing agent of incineration ash in any one of Claim 1 thru | or 4 which performs step 4 which carries out natural dehydration or forced dehydration of ash, ie, decontamination ash. In step 1,
The waste in the incineration ash is removed by passing the incineration ash through a sieve,
In step 2,
The washing water is water, and the incinerated ash is added to the water in the same weight as the water to make the mud water in a mud state;
A step 22 of charging 3 to 5% by weight of the treatment agent with respect to 100% by weight of the slurryed water;
After the treatment agent has been added, the slurryed water is adjusted to be strongly acidic and stirred with a stirrer for a predetermined time, so that the contaminants in the incinerated ash are eluted into the slurryed water and allowed to stand for a predetermined time to settle. Step 23 is performed,
In step 3 above,
Step 31 in which 0.02 to 0.03% by weight of ferric polysulfate is added to 100% by weight of contaminated water which is the supernatant liquid separated by the precipitation;
0.04 to 0.06% by weight of the polymer flocculant, which is a liquid whose pH is adjusted to be almost neutral, with respect to 100% by weight of the contaminated water before the execution of step 31 which is the supernatant separated by the precipitation. The step 32 of clarifying the contaminated water is performed by separating and collecting the aggregated block that has been added and stirred for a predetermined time with an agitator.
In step 4 above,
The method for treating incinerated ash according to claim 5, wherein the decontamination ash as the precipitate is subjected to the natural dehydration or forced dehydration. In the step 4, the decontamination ash is forcibly dehydrated by performing mechanical dehydration with a dehydrator,
The said contaminated water which removed the said aggregation block by the said step 32, and each of the water | moisture content isolate | separated from the decontamination ash by the spin-drying | dehydration of the said step 4 are reused as a wash water of step 2. Incineration ash treatment method.

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