JP6610855B2 - Processing method of heavy metal treatment material and heavy metal containing fly ash cleaning liquid - Google Patents

Description

  The present invention relates to a heavy metal treatment material capable of treating heavy metals eluted in a fly ash cleaning liquid and a heavy metal treatment method using the same. More specifically, the present invention relates to a heavy metal treatment material containing Ba, Fe, and Mg having a specific blending ratio and a heavy metal treatment method using the same.

  Incineration fly ash generated in waste incinerators, melting furnaces, etc. has a high alkalinity of pH 12 or higher, and often contains various alkali metals and alkaline earth metal salts at high concentrations and harmful heavy metals. Further, fly ash may contain chlorine at a high concentration. Usually, after the fly ash is washed to remove the chlorine content, it is disposed of or reused as a raw material for cement. However, there are many cases in which heavy metals such as Se and Pb are eluted in the cleaning liquid, and the cleaning liquid must be appropriately treated to less than the drainage standard for each heavy metal. The drainage standard for Se is less than 0.1 mg / l and the drainage standard for Pb is less than 0.1 mg / l.

  Conventionally, as a method for removing heavy metals in the fly ash cleaning liquid, a method of filtering and separating precipitates by adding a sulfurizing agent such as sodium hydrosulfide and a ferrous or ferric compound to the liquid to be treated is proposed. (Patent Document 1). Also, depending on the type of heavy metal, it is difficult to treat, so measures are taken to reduce the concentration by mixing and diluting with wastewater in a separate process.

As a treatment material for various heavy metal ions such as Se and Pb, a part of lightly burned magnesia obtained by firing a mineral mainly composed of magnesium carbonate and / or magnesium hydroxide at 650 to 1,000 ° C. is hydrated. A light-burned magnesia partial hydrate is proposed (Patent Document 2). MgCxOy that minerals containing magnesium carbonate and (MgCO ₃₎ and calcium carbonate (CaCO ₃₎ as a main component is being light burned, and the MgCO ₃ is produced by being decarboxylated (where, 0 <x ≦ 1 , 0 <satisfy y <3.), and MgCO _3, process material mainly composed of MgO, such as heavy metal elution reducing material containing light burned product and a CaCO ₃ has been proposed (Patent Document 3) .

JP 2010-051868 A JP 2012-177051 A JP 2013-230447 A

  However, in order to process trace amounts of heavy metals in solutions containing high-concentration salts such as fly ash cleaning liquid, it is necessary to add a large amount of treatment material and less than the standard value for difficult-to-process metals such as selenium A heavy metal treatment material and a treatment method in a fly ash cleaning liquid that cannot be treated in a simple manner and can be removed more easily and economically have not been provided yet.

That is, in the aforementioned Patent Document 1, a method of adding a sulfurizing agent such as sodium hydrosulfide and a ferrous compound or a ferric compound to the liquid to be treated and filtering the precipitate is described. In these methods, it is possible to achieve a drainage standard value of less than 0.1 mg / l for lead, but it is not possible to clear the standard value of 0.1 mg / l for selenium. Moreover, although the above-mentioned patent document 1 describes the method of reducing a selenium density | concentration by mixing and dilution with the water treatment of another process, it cannot be said that selenium has been processed substantially.
In addition, the sulfurizing agent used is difficult to handle in terms of workability because it generates harmful hydrogen sulfide in contact with an acid solution.

As a treatment material for heavy metal ions, the above-mentioned Patent Document 2 discloses a part of light-burned magnesia obtained by firing a mineral mainly composed of magnesium carbonate and / or magnesium hydroxide at 650 to 1,000 ° C. A light calcined magnesia partial hydrate is described. In the aforementioned Patent Document 3, a mineral containing magnesium carbonate (MgCO ₃ ) and calcium carbonate (CaCO ₃ ) as main components is lightly calcined. becomes, and MgCxOy said MgCO ₃ is produced by being decarboxylated (where 0 <satisfy x ≦ 1,0 <y <3. ) and, and MgCO _3, light burned product comprising a CaCO ₃ A heavy metal elution reducing material containing is described. However, for any wastewater containing multiple heavy metals containing high-salt concentration and difficult-to-process selenium such as fly ash cleaning liquid, it is easy to remove simultaneously to below the wastewater standard value. There is no description, and there has been no heavy metal treatment material and heavy metal treatment method effective for these heavy metal-containing wastewaters.

  The present invention has been made in view of such circumstances, and for the heavy metal wastewater contained in the fly ash cleaning liquid, the concentration of heavy metals of a plurality of heavy metals in the treated water is easily and economically determined. At the same time, the purpose is to treat it below the effluent standard.

  The technical problem can be achieved by the present invention as follows.

  That is, in the present invention, after adjusting the pH of the fly ash cleaning liquid to 8 to 10, the fly ash cleaning liquid is mixed with barium chloride, ferrous sulfate and magnesium oxide, and the mixing molar ratio of barium, iron and magnesium is Ba / Heavy metal-containing fly ash cleaning liquid, characterized in that the heavy metal in the fly ash cleaning liquid is treated so that Fe = 3-50, Ba / Mg = 0.4-5, and Mg / Fe = 3-25. (Invention 1).

Further, the present invention is, Ca dissolved in the fly ash washing liquid, SO ₄ concentration is the 500~10000mg / l, a processing method of the heavy metal-containing fly ash washing liquid according to the present invention 1, the pH is 12 or more ( Invention 2).

  Moreover, the present invention includes the heavy metal according to the first or second aspect of the present invention, wherein the heavy metal species in the fly ash cleaning liquid includes Se and Pb, and further includes any one or more selected from Cr, F, B, As, and Cd. It is a processing method of a fly ash washing | cleaning liquid (this invention 3).

  Moreover, this invention is a processing method of the heavy metal containing fly ash washing | cleaning liquid in any one of this invention 1-3 whose treated water pH after a process is 5.8-8.6 (this invention 4).

  Moreover, this invention is a processing method of the heavy metal containing fly ash washing | cleaning liquid in any one of this invention 1-4 which adds barium chloride, ferrous sulfate, and magnesium oxide to a fly ash washing | cleaning liquid in the state of a mixture ( Invention 5).

  Further, the present invention is a heavy metal treatment material comprising a mixture of barium chloride, ferrous sulfate and magnesium oxide, and the blending molar ratio of barium, iron and magnesium in the heavy metal treatment material is Ba / Fe = 3-50. Ba / Mg = 0.4-5, Mg / Fe = 3-25 (invention 6).

  By the method for treating heavy metal-containing fly ash cleaning liquid according to the present invention, heavy metals existing in wastewater containing high salt concentration and difficult-to-treat Se such as fly ash washing liquid are easily and efficiently removed to below the wastewater standard value. it can.

  Further, in the method for treating heavy metal-containing fly ash cleaning liquid according to the present invention, the treated water pH after the treatment can be within the drainage standard value, and the amount of the pH adjusting agent used before and after the treatment of the waste water can be reduced, Wastewater can be treated more economically.

  In addition, by using the heavy metal treatment material according to the present invention, heavy metals present in wastewater containing high salt concentration and difficult-to-treat Se, such as fly ash washing liquid, can be easily and efficiently removed to below the drainage standard value. In addition, the pH after treatment of the cleaning liquid can be within the drainage reference value, the amount of the pH adjusting agent used before and after the treatment of the wastewater can be reduced, and the wastewater can be treated more economically.

  The configuration of the present invention will be described in more detail as follows.

  First, the processing method of the heavy metal containing fly ash washing | cleaning liquid which concerns on this invention is described.

  Heavy metal contaminants in the present invention include various types of coal ash generated from coal-fired power plants, boiler fly ash generated by combustion of biomass fuel, chlorine bypass dust discharged from cement manufacturing processes, paper sludge-derived incineration ash, etc. Target fly ash.

  The present invention adds a predetermined compound to the heavy metal-containing fly ash washing liquid generated when the fly ash containing heavy metals as described above is washed with water, thereby reducing the concentration of each heavy metal to less than the wastewater standard value. .

The washing of fly ash is usually performed by adding 100 to 1000 parts by mass of water to 100 parts by mass of fly ash, stirring and mixing, and then solid-liquid separating the fly ash and the washing liquid with a filter press or the like.
The obtained fly ash cleaning solution exhibits an alkaline pH of 12 or more, and the solution contains Se, Pb and various heavy metals, Ca, SO ₄ in addition to high concentrations of K, Na, Cl, and Ca, SO The concentration of ₄ is 500 to 10,000 mg / l. Even if the fly ash cleaning liquid further contains any one or more elements selected from Cr, F, B, As, and Cd and compounds thereof, each heavy metal is reduced to a predetermined concentration or less by the treatment method according to the present invention. Can be reduced.

In the fly ash cleaning liquid in the present invention, Ca and SO ₄ concentrations are preferably contained in the range of 500 to 10,000 mg / l, respectively.
When the concentration is lower than this concentration range, a drug or the like can be added as appropriate to adjust to this concentration range. Conversely, if the concentration range is exceeded, the treatment itself is possible, but in some cases, the amount of treatment material added tends to increase, which is not economically preferable. preferable.

As a drug used for adjusting the concentration of Ca and SO ₄ , calcium chloride or the like can be used for Ca, and sulfuric acid solution, sodium sulfate or the like can be used for SO ₄ , but it dissolves in the solution and releases Ca and SO ₄ . If it is a substance, it will not specifically limit.

  The processing method of the heavy metal containing fly ash washing | cleaning liquid which concerns on this invention adjusts pH to 8-10 by adding an acid solution with respect to the said fly ash washing | cleaning liquid. If the pH is less than 8, the amount of the acid solution to be used is increased, the heavy metal treatment property is deteriorated, and the pH of the treated water is lowered. On the other hand, when the pH exceeds 10, the treatment with heavy metals is lowered and the pH of the treated water is increased, which is not preferable.

  Common acids such as hydrochloric acid and sulfuric acid can be used for the acid solution.

  In the method for treating a heavy metal-containing fly ash cleaning liquid according to the present invention, barium chloride, ferrous sulfate and magnesium oxide are added to the cleaning liquid after pH adjustment. Each of barium chloride, ferrous sulfate and magnesium oxide may be added alone, or may be added in a premixed state as will be described later, and is present in a predetermined molar ratio in the fly ash cleaning liquid. What should I do?

  The abundance ratio of barium chloride, ferrous sulfate, and magnesium oxide is Ba / Fe = 3-50, Ba / Mg = 0.4-5, and Mg / Fe = 3-25 as the molar ratio of barium, iron, and magnesium. is there. If these molar ratios are out of the range, the heavy metal processability tends to be reduced, and the pH of the treated water also deviates from the drainage standard and requires a separate pH adjustment, leading to high treatment costs. A preferable blending ratio is Ba / Fe of 3 to 40, more preferably 3 to 32, Ba / Mg is 0.4 to 5, Mg / Fe is 3.5 to 20, and more Preferably it is 4-17.

  Examples of the barium chloride in the present invention include barium chloride dihydrate, barium chloride anhydride and the like. Although there is no restriction | limiting in particular as a particle size, A thing of 5 mm or less is preferable, More preferably, a thing of 2 mm or less is preferable.

  Examples of the ferrous sulfate in the present invention include ferrous sulfate heptahydrate, ferrous sulfate monohydrate, ferrous sulfate anhydrate. Although there is no restriction | limiting in particular as a particle size, A thing of 5 mm or less is preferable, More preferably, a thing of 2 mm or less is preferable.

  Examples of the magnesium oxide in the present invention include a fired product obtained by firing a solid containing magnesium carbonate and magnesium hydroxide as main components at 700 to 1000 ° C.

  Examples of the solid material mainly composed of magnesium carbonate and / or magnesium hydroxide include brucite, magnesite, and dolomite, but are not particularly limited.

  Even if impurities such as Ca and Si compounds are contained in the magnesium oxide, there is no particular problem. However, the MgO content is preferably 75% or more, and more preferably 80% or more.

  The average particle size of the magnesium oxide is preferably 5 to 500 μm, more preferably 10 to 200 μm. If it is less than 5 μm, the handling property of the powder is lowered, which is not preferable. On the other hand, when it exceeds 500 μm, the heavy metal processability is lowered and the solid-liquid separation property after the process is deteriorated.

The total addition amount of barium chloride, ferrous sulfate and magnesium oxide in the present invention depends on the heavy metal concentration and the like in the obtained fly ash cleaning liquid, but is preferably 0.1 to 50 kg per 1 m ^{3 of} the cleaning liquid, 0.3 -30 kg is more preferable. If the addition amount is less than 0.1 kg, the removal of heavy metals is insufficient, and if it exceeds 50 kg, the removability is sufficient, but excessive addition results in an increase in cost. The method of mixing the fly ash cleaning liquid with barium chloride, ferrous sulfate and magnesium oxide is not particularly limited.

  After adding barium chloride, ferrous sulfate and magnesium oxide to the fly ash cleaning solution and mixing it, treated water in which the concentration of heavy metals has been reduced to below the effluent standard value by solid-liquid separation of solids containing heavy metals Can be obtained.

  The pH of the obtained treated water is in the range of 5.8 to 8.6, which is a drainage standard, and there is no need to adjust the pH in a subsequent process.

  Next, the heavy metal treating agent according to the present invention will be described.

  The heavy metal treatment material according to the present invention is a mixture of barium chloride, ferrous sulfate and magnesium oxide. The content ratio of barium chloride, ferrous sulfate and magnesium oxide in the heavy metal treatment material is set to Ba / Fe = 3 to 50, Ba / Mg = 0.4 to 5, Mg as the mixing molar ratio of barium, iron and magnesium. What is necessary is just to mix so that it may become / Fe = 3-25. A preferable blending ratio is Ba / Fe of 3 to 40, more preferably 3 to 32, Ba / Mg is 0.4 to 5, Mg / Fe is 3.5 to 20, and more Preferably it is 4-17.

  As the barium chloride and ferrous sulfate, the above-mentioned various compounds can be used. Although there is no restriction | limiting in particular as those particle sizes, A thing of 5 mm or less is preferable, More preferably, a thing of 2 mm or less is preferable. Further, in the magnesium oxide, the above-mentioned various compounds can be used, and the particle diameter is not particularly limited, but the average particle diameter is preferably 5 to 500 μm, more preferably 10 to 200 μm. If it is less than 5 μm, the handling property of the powder is lowered, which is not preferable. On the other hand, when it exceeds 500 μm, the heavy metal processability is lowered and the solid-liquid separation property after the process is deteriorated.

1-15 m < ² > / g is preferable and, as for the BET specific surface area value of the heavy metal processing material which concerns on this invention, More preferably, it is 3-10 m < ² > / g. When the BET specific surface area value is less than 1 m ² / g, the contact area between the heavy metal ions and the heavy metal treatment material is small and the processability is lowered, which is not preferable. If it exceeds 15 m ² / g, there is no problem in the processability of heavy metals, but the solid-liquid separability after heavy metal processing deteriorates with the deterioration of the handleability of the powder.

  Next, the manufacturing method of the heavy metal processing material which concerns on this invention is described.

  The heavy metal treatment material in the present invention can be obtained by mixing and pulverizing a barium raw material, an iron raw material, and a magnesium raw material.

  Mixing and pulverization of the three types of raw materials may be performed at one time, but after mixing and pulverizing the two raw materials, the remaining one raw material may be mixed and pulverized. There is no particular restriction on the order.

  Further, in order to obtain a predetermined particle size and BET value, pulverization may be carried out depending on circumstances, and pulverization may be omitted when a predetermined BET value and particle size can be obtained only by mixing.

  As a dry-type apparatus that performs mixing, it is possible to use a rake machine, a ribbon mixer, a kneader, a pug mill, a sand mill, a fixed container type such as a henschel shell mixer, a rotating container type such as a concrete mixer, and the like.

  A ball mill, a free crusher, a hammer mill or the like can be used as an apparatus for performing the crushing.

<Action>
The important point in the present invention is that, by using the heavy metal-containing fly ash cleaning liquid treatment method according to the present invention, the concentration of each heavy metal is simultaneously reduced to less than the wastewater standard even in the high salt concentration and the fly ash cleaning liquid containing a plurality of heavy metals. Moreover, since the pH of the treated water also meets the drainage standard, it is a fact that the treatment process can be simplified and the amount of chemicals used can be reduced.

Conventional heavy metal treatment materials and treatment methods for heavy metal containing wastewater using high-concentration salts such as fly ash cleaning liquid and heavy metals with different concentrations due to the presence of coexisting substances such as Ca and SO _4. At the same time, it could not be reduced easily and economically to below the effluent standard value.

  The processing method of the heavy metal-containing fly ash cleaning liquid according to the present invention is stable in the treatment of difficult-to-process selenium as well as lead, hexavalent chromium, arsenic, etc. even in the presence of a high concentration of coexisting substances. In addition, since it is possible to perform treatment only by adjusting the pH before treatment, the amount of drug used can be reduced.

  Moreover, the heavy metal processing material which concerns on this invention is accelerated | stimulated by the precipitation generation and the growth of floc by adding and stirring in a fly ash washing | cleaning liquid, and it is excellent also in solid-liquid separation.

  A typical embodiment of the present invention is as follows.

  The BET specific surface area value of the heavy metal treated material in the present invention is indicated by a value measured by the BET method.

  The analysis of K, Na, Ca, S, and B concentrations in the fly ash cleaning solution and the treatment solution in the present invention is measured by “Plasma emission spectroscopy analyzer (ICP) iCAP6300 (manufactured by Thermo Fisher Scientific Co., Ltd.)”. And asked. The F concentration was measured by absorptiometry based on JIS K 0102 34.1, and the Cl concentration was measured using “Ion Chromato (IC) ICA-2000 (manufactured by Toa DKK Co., Ltd.)”. Se, Pb, The Cr and Cd concentrations were determined by measurement by ICP mass spectrometry.

(Treatment material 1)
18 g of barium chloride dihydrate, 0.4 g of ferrous sulfate monohydrate and 1.6 g of magnesium oxide were mixed at the same time, so that the molar ratios of Ba, Fe and Mg were Ba / Fe = 31.3 and Ba, respectively. A heavy metal treated material with /Mg=1.9 and Mg / Fe = 16.9 was prepared. The obtained heavy metal treatment material had a BET specific surface area of 4.3 m ² / g.

(Treatment materials 2-14)
It was prepared in the same manner as the treatment material 1 except that the blending molar ratio of Ba, Fe, and Mg contained in the heavy metal treatment material was changed.

  Table 1 shows the blending amount and blending composition of the heavy metal treatment material.

(Fly ash cleaning solution)
・ Raw water (1)
A filtrate obtained by adding 600 g of water to 300 g of fly ash generated from a boiler accompanying combustion of biomass and stirring, washing, and filtering was used as a fly ash washing solution. The fly ash cleaning solution contains Se 2.1 mg / l and Pb 33.0 mg / l as heavy metals, and other main coexisting substances are K2.2%, Na 0.7%, Cl 10.0%, Ca 1850 mg / l, SO ₄ 5370 mg / l, pH was 12.7, and electrical conductivity was 180 mS / cm.
・ Raw water (2)
Potassium dichromate, sodium fluoride, boric acid, sodium arsenite, cadmium nitrate were added to raw water (1) to add Cr 0.9 mg / l, F 2.3 mg / l, B 1.2 mg / l, As 0.4 mg / l, raw water (2) containing Cd 0.5 mg / l was prepared.

Example 1
Sulfuric acid was added while stirring 100 ml of the fly ash washing solution (raw water (1)) to adjust the pH to 9.3, and then 1.5 g of treatment material 1 was added and stirred for 2 hours. Thereafter, stirring was stopped and the mixture was allowed to stand for 10 minutes, and the resulting precipitate was observed. The supernatant liquid after standing was filtered through a 0.45 μm membrane filter, and the heavy metal concentration and pH in the obtained filtrate were measured.

Example 2
In Example 1, the treatment operation was performed in the same manner except that the pH of the raw water (1) was 9.4 and the treatment material 2 was used.

Example 3
In Example 1, the treatment operation was performed in the same manner except that the pH of the raw water (1) was 9.1 and the treatment material 3 was used.

Example 4
In Example 1, the treatment operation was performed in the same manner except that the pH of the raw water (1) was 8.9 and the treatment material 4 was used.

Example 5
In Example 1, the treatment operation was performed in the same manner except that the pH of the raw water (1) was 9.5 and the treatment material 5 was used.

Example 6
In Example 1, the treatment operation was performed in the same manner except that the pH of the raw water (1) was 9.4 and the treatment material 6 was used.

Example 7
In Example 5, the raw water (2) was used instead of the raw water (1), and the treatment operation was carried out in the same manner except that the pH was 8.8.

Comparative Example 1
Sulfuric acid was added while stirring 100 ml of the fly ash washing solution (raw water (1)) to adjust the pH to 9.3, and then 1.5 g of treatment material 7 was added and stirred for 2 hours. Thereafter, stirring was stopped and the mixture was allowed to stand for 10 minutes, and the resulting precipitate was observed. Thereafter, the supernatant was filtered through a 0.45 μm membrane filter, and the heavy metal concentration and pH in the obtained filtrate were measured.

Comparative Example 2
The treatment operation was performed in the same manner as in Comparative Example 1 except that the pH of the raw water (1) was 9.3 and the treatment material 8 was used.

Comparative Example 3
The treatment operation was performed in the same manner as in Comparative Example 1 except that the pH of the raw water (1) was 9.4 and the treatment material 9 was used.

Comparative Example 4
The treatment operation was carried out in the same manner except that the pH of the raw water (1) was 9.2 and the treatment material 10 was used in Comparative Example 1.

Comparative Example 5
The treatment operation was performed in the same manner as in Comparative Example 1 except that the pH of the raw water (1) was 9.2 and the treatment material 11 was used.

Comparative Example 6
The treatment operation was carried out in the same manner except that the pH of the raw water (1) was 9.2 and the treatment material 12 was used in Comparative Example 1.

Comparative Example 7
The treatment operation was performed in the same manner as in Comparative Example 1 except that the pH of the raw water (1) was 9.3 and the treatment material 13 was used.

Comparative Example 8
The treatment operation was performed in the same manner as in Comparative Example 1 except that the pH of the raw water (1) was 9.1 and the treatment material 14 was used.

Comparative Example 9
The treatment operation was carried out in the same manner as in Example 4 except that the pH of the raw water (1) was 11.3.

Comparative Example 10
The treatment operation was performed in the same manner as in Example 4 except that the pH of the raw water (1) was 6.1.

  Table 2 shows the results of heavy metal concentration in the treated water, treated water pH, and solid-liquid separability when various treated materials are used.

In Examples 1 to 6 in Table 2, the ranges of the molar ratios of Ba, Fe, and Mg in the treatment material are Ba / Fe = 3 to 50, Ba / Mg = 0.4 to 5, and Mg / Fe = 3 to 3, respectively. The heavy metal treatment material set to 25 was used, and when these treatment materials were used, each heavy metal concentration in the fly ash cleaning liquid achieved less than the wastewater standard value. Further, the pH of the treated water is within the range of 5.8 to 8.6 of the drainage standard, and it was not necessary to adjust the pH separately.
Moreover, the sedimentation property of the precipitated product after the treatment was good, and the supernatant liquid after standing for 10 minutes after stopping the stirring became almost transparent, and the solid-liquid separation property was also excellent.
In Example 7, all heavy metals could be treated even when wastewater to which Cr, F, B, As, and Cd were additionally added was used.

On the other hand, in Comparative Examples 1 to 8, the blending molar ratios of Ba, Fe, and Mg in the treatment material are in the range of Ba / Fe = 3 to 50, Ba / Mg = 0.4 to 5, and Mg / Fe = 3 to 25. The removed heavy metal treatment materials were used, and when these treatment materials were used, the heavy metal concentration in the treatment liquid exceeded the drainage standard value.
Moreover, since the pH after the treatment sometimes deviated from the drainage standard range, it was necessary to separately adjust the pH.
Furthermore, the sedimentation property of the precipitated product after the heavy metal treatment was poor, and SS in which the product was partially suspended was also observed in the supernatant after standing.

In Comparative Example 9, the pH was 11.3 exceeding the raw water pH adjustment range of the present invention. The Se concentration after the treatment exceeded the reference value and the Pb concentration significantly exceeded the reference value. The treated water pH was also outside the range of the standard value.
In Comparative Example 10, the pH was 6.1 lower than the raw water pH adjustment range of the present invention, the Pb concentration after the treatment exceeded, and Se and Pb could not be treated at the same time below the reference value.

The processing method of the heavy metal-containing fly ash cleaning liquid according to the present invention is to treat various heavy metal concentrations to below the effluent standard value simultaneously with a simple processing operation for wastewater containing a plurality of heavy metals at a high salt concentration like the fly ash cleaning liquid. It is possible to adjust the pH after the treatment and is preferable.

Claims (5)

After adjusting the pH of the fly ash washing liquid having a dissolved Ca and SO ₄ concentration of 500 to 10000 mg / l and a pH of 12 or more to the fly ash washing liquid, barium chloride, ferrous sulfate and Magnesium oxide is present so that the blending molar ratio of barium, iron and magnesium is Ba / Fe = 3-50, Ba / Mg = 0.4-5, Mg / Fe = 3-25, A method for treating heavy metal-containing fly ash cleaning liquid, characterized by treating heavy metal therein. It includes a heavy metal species Se and Pb of fly ash in the cleaning solution, further, Cr, F, B, As, processing method of heavy metal-containing fly ash washing solution according to claim 1 Symbol mounting comprises any one or more selected from Cd. The processing method of the heavy metal containing fly ash washing | cleaning liquid of Claim 1 or 2 whose treated water pH after processing is 5.8-8.6. The processing method of the heavy metal containing fly ash washing | cleaning liquid in any one of Claims 1-3 which adds barium chloride, ferrous sulfate, and magnesium oxide to a fly ash washing | cleaning liquid in the state of a mixture. A heavy metal treatment material comprising a mixture of barium chloride, ferrous sulfate and magnesium oxide, wherein the mixing molar ratio of barium, iron and magnesium in the heavy metal treatment material is Ba / Fe = 3 to 50, Ba / Mg = 0. 4-5, Mg / Fe = 3-25, Heavy metal treatment material characterized by the above-mentioned.