JP7244803B2 - Method for modifying boron-containing slag, method for manufacturing civil engineering and construction materials using the same, and modified slag - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for modifying boron-containing slag, a method for producing civil engineering and construction materials using the same, and a modified slag.

With the development of industry, the amount of industrial by-products generated in various industries is steadily increasing. In recent years, effective utilization of such industrial by-products has been carried out from the viewpoint of global environment conservation. For example, steel slag such as blast furnace slag and steelmaking slag generated from steel plants, coal ash generated from thermal power plants, and molten slag obtained by melting, cooling, and solidifying waste and sewage sludge incineration ash at high temperatures, After proper grain size adjustment, it is reused as a civil engineering and construction material such as roadbed material and soil improvement material.

When reusing industrial by-products, it is necessary to suppress the emission of harmful substances contained therein into the environment. Typical harmful substances include heavy metals such as cadmium, mercury, chromium and lead. In addition to these heavy metals, for example, fluorine, selenium, arsenic and boron are also harmful to the environment. , the emission (elution) into the environment is strictly regulated.

Among the components that adversely affect the environment, methods for suppressing the elution of boron include, for example, a method of adding and mixing magnesium oxide in the form of powder or slurry to incineration ash containing boron (Patent Document 1 ), and a method of humidifying and curing coal ash discharged from a thermal power plant for a predetermined period (Patent Document 2).

Japanese Patent Application Laid-Open No. 2004-298741 JP 2007-90155 A

However, in the method described in Patent Document 1, the magnesium oxide used as the boron elution inhibitor is expensive, and the mixture (final product) to which the elution inhibitor is added hardens and has a relatively high strength. Since it becomes a lump of this, there is a problem that it takes time and effort to adjust the particle size for using this as a material. In addition, in the method described in Patent Document 2, long-term humidification curing is required in order to suppress the elution of boron. Low productivity is a problem because it requires long-term moisturizing and curing.

In addition to this, as a method for determining the elution of boron from a boron-containing substance, the method specified in the Environment Agency Notification No. 46, which is also described in Patent Document 1, is known. Preparation, sample solution preparation, dissolution treatment, and test solution preparation were required before analysis, which required time and effort for determination. Therefore, in many cases, all boron-containing substances are subjected to elution suppression treatment without determining the elution of boron in advance. In this case, the amount of eluted boron is small, and even the boron-containing substance, which originally does not need to be subjected to the elution suppression treatment, is subjected to the treatment, which is uneconomical.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to solve the aforementioned problems and to provide a method for simply and economically suppressing the elution of boron from the boron-containing slag, which is one of the industrial by-products.

As a result of various studies in order to solve the above problems, the present inventors found that from the composition of the boron-containing slag, using equilibrium calculations, the boron concentration in the liquid phase in the boron-containing slag in a solid-liquid coexistence state was calculated, and it was found that whether or not the amount of eluted boron from the boron-containing slag satisfies the environmental standards can be determined depending on whether or not the boron concentration is equal to or lower than a predetermined threshold. Then, by adding a modifier so that the boron concentration becomes a predetermined threshold value or less and then cooling at high speed, the slag can be modified so that the boron elution amount satisfies the environmental standards, and the present invention has been completed. rice field.

That is, the first embodiment of the present invention for solving the above problems is a method for modifying boron-containing slag, wherein the slag is in a solid-liquid coexistence state by equilibrium calculation based on the composition of the slag before modification. Calculating the calculated boron concentration C1 before reforming, which is the boron concentration in _the liquid phase at a certain predetermined temperature T, and for the slag before reforming, where the calculated boron concentration _C1 before reforming exceeds a predetermined threshold value C, At the predetermined temperature T or higher, a modifier that contains 30% by mass or more of SiO ₂ and dissolves in the liquid phase of the slag at the predetermined temperature T is added to modify it, and the slag is modified based on the composition. Preparing a modified slag in which the post-reformation calculated boron concentration _C2 in the liquid phase at a predetermined temperature T in a solid-liquid coexistence state, calculated by equilibrium calculation, is equal to or less than the predetermined threshold value C, and Pouring the modified slag in a thin layer, and cooling the central portion of the thin layer in the thickness direction at a cooling rate of 10 ° C./min or more from the predetermined temperature T to 1000 ° C. of boron-containing slag. It is a modification method. However, the predetermined threshold value C is a value selected from the range of 0.5% by mass to 1.0% by mass, and the predetermined temperature T is calculated from the powder X-ray diffraction measurement result of the slag before reforming. The temperature is ±50° C. at which the proportion of the liquid phase in the solid-liquid coexistence state calculated by the equilibrium calculation agrees with the proportion of the glass phase present in the slag at room temperature.

Further, the second embodiment of the present invention is a method for producing a material for civil engineering and construction, in which the modified slag obtained by the method for modifying boron-containing slag according to the first embodiment is used as a material. A method for manufacturing a material for civil engineering and construction, characterized by:

Furthermore, the third embodiment of the present invention contains boron-containing slag with a boron content of more than 0.15% by mass and _SiO2 of 30% by mass or more, and is calculated by equilibrium calculation based on the composition of the slag. A modified slag mixed with a modifier that dissolves in the liquid phase of the slag at a predetermined temperature T within the range of 1100 ° C. to 1200 ° C., wherein the liquid phase at the predetermined temperature T The boron concentration and the SiO ₂ concentration are 1.0% by mass or less and 25% by mass or more, respectively, and the boron elution amount according to the elution test specified by the Environment Agency Notification No. 46 is 1 mg / L or less. It is a modified slag.

ADVANTAGE OF THE INVENTION According to this invention, the method which can suppress the elution of the boron from the boron containing slag among industrial byproducts simply and economically can be provided.

Hereinafter, each embodiment of the present invention will be described in detail, but the present invention is not limited to each embodiment. In addition, the mechanism of action described below includes presumptions, and its correctness does not limit the present invention. It should be noted that the description of a numerical range (a description in which two numerical values are connected by "-") is meant to include numerical values described as lower and upper limits.

In the process of studying to solve the above-mentioned problems, the present inventors found that the amount of boron eluted from the boron-containing slag does not necessarily match the level of the boron concentration of the slag, and that the boron-containing slag having the same composition It was found that even slag exhibits different amounts of boron elution when the cooling rate from the molten state is different. Therefore, in order to elucidate these causes, we calculated the glass phase ratio based on the X-ray diffraction (XRD) measurement results, confirmed the uneven distribution of boron with an electron probe microanalyzer (EPMA), and transmitted electron Boron distribution in the glass phase was observed using an electron energy loss spectroscopy (TEM-EELS) device attached to the microscope. As a result, it was found that the concentration of boron in the glass phase and the stability of boron in the glass phase greatly affect the amount of boron eluted from the boron-containing slag.
Each embodiment of the present invention described later is based on this finding.

[Method for reforming boron-containing slag]
The method for modifying boron-containing slag according to the first embodiment of the present invention (hereinafter sometimes simply referred to as "first embodiment") is a boron-containing slag to be modified (hereinafter referred to as "improving By equilibrium calculation based on the composition of the slag before reforming, the calculated boron concentration _C1 before reforming, which is the boron concentration in the liquid phase at a predetermined temperature T at which the slag is in a solid-liquid coexistence state, is calculated. Including calculating.

Examples of pre-reformation slag include iron and steel slag such as blast furnace slag and steelmaking slag generated from steelworks, and various types of slag such as molten slag obtained by melting, cooling and solidifying incineration ash of waste and sewage sludge at high temperatures. be done. In addition, for those that are in a molten state at the time of production, they may be reformed while they are in a molten state.

Calculation of the calculated boron concentration before reforming _C1 is performed by equilibrium calculation based on the composition of the slag before reforming, and at a predetermined temperature T at which the slag is in a solid-liquid coexistence state, the concentration of boron present on the liquid phase side is calculated. Do it by asking.
The composition of the pre-modification slag used for the equilibrium calculation can be obtained by quantifying the slag by X-ray fluorescence (XRF) analysis or the like. Also, based on the analysis results of boron-containing slag produced under predetermined conditions, the composition of boron-containing slag expected from changes in the conditions may be used.
In the equilibrium calculation, first, the predetermined temperature T is determined as follows. That is, from the composition of the slag before reforming, the temperature range in which the slag is in a solid-liquid coexistence state is calculated, and the ratio of the liquid phase at each temperature within the temperature range is calculated. Also, from the powder X-ray diffraction measurement result of the slag before reforming, the ratio of the glass phase present in the slag at room temperature is calculated. Here, the term "ordinary temperature" as used herein means a temperature at which no cooling or heating is performed, and generally refers to a temperature of about 5°C to 35°C. Then, the temperature at which the ratio of the liquid phase coincides with the ratio of the glass phase is obtained, and the predetermined temperature T is determined within the temperature range of ±50°C. At this time, by setting the predetermined temperature T to 1100° C. to 1200° C., the proportion and composition of the liquid phase calculated from the equilibrium calculation are adjusted to the proportion and composition of the glass phase present in the slag before reforming at room temperature. It is possible to make it closer, and it is preferable because it is possible to determine the necessity of adding a modifier, which will be described later, with higher accuracy.
Next, from the predetermined temperature T and the composition of the slag before reforming, the concentration of boron present in the liquid phase at the predetermined temperature T is calculated, and this is defined as the calculated boron concentration before reforming _C1 .

The calculated pre-reforming calculated boron concentration _C1 corresponds to the boron concentration in the glass phase present at room temperature in the actual pre-reforming slag. Therefore _, in the first embodiment, based on the above findings, it is determined that the amount of eluted boron in the slag before reforming exceeds the predetermined threshold value C, and the boron elution amount may exceed the environmental standard. , Reuse or final disposal after undergoing modification treatment to be described later.

Here, the predetermined threshold value C is a value selected from the range of 0.5% by mass to 1.0% by mass. By setting the threshold value C to a value of 1.0% by mass or less, even when the stability of boron contained in the glass phase is low, the amount of boron actually eluted from the slag before reforming exceeds the environmental standard. can be effectively prevented. The threshold value C is preferably set to a value of 0.8% by mass or less. On the other hand, by setting the threshold to a value of 0.5% by mass or more, there is a possibility that the slag before reforming, in which the amount of boron actually eluted satisfies the environmental standards, is subjected to unnecessary reforming treatment. can be made smaller. The threshold value C is preferably set to a value of 0.6% by mass or more.
When determining the predetermined threshold value C, considering the stability of boron in the glass phase that exists in the slag before reforming at room temperature, the amount of boron eluted from the slag should be within a range that does not exceed the environmental standard. Just do it. For example, when the slag before modification is a slag obtained by cooling and solidifying a melt, the slag obtained by rapid cooling has high stability of boron in the glass and is difficult to elute, so the threshold value C is Can be set relatively large. On the contrary, in the pre-modification slag obtained by slow cooling from the molten state, boron is easily eluted, so the threshold value C is set relatively small. When setting the threshold value C for the pre-reforming slag in a molten state, the threshold value C may be set in consideration of the cooling rate and the like under normal operating conditions.

In the first embodiment, 30% by mass or more of _SiO2 is contained in the pre-reforming slag in which the pre-reforming calculated boron concentration _C1 exceeds a predetermined threshold C, and the pre-reforming slag is at the predetermined temperature T or higher, and the predetermined A modifier that dissolves in the liquid phase of the slag at temperature T is added to modify it, and the liquid phase at the predetermined temperature T in a solid-liquid coexistence state calculated by equilibrium calculation based on the composition and preparing a modified slag in which the post-modification calculated boron concentration _C2 is equal to or lower than the predetermined threshold value C. As a result, the composition of the slag before reforming is changed, and the calculated boron concentration in the liquid phase at the predetermined temperature T, that is, the calculated boron concentration after reforming _C2 is set to the threshold value C or less.
In selecting the modifier, the ratio of the mass of the added modifier dissolved in the liquid phase of the slag at the predetermined temperature T ((mass of the dissolved modifier) / (added modifier The mass of the material)×100) is 10% or more. In actual operation, the modifier is often added at a predetermined temperature T or higher. Generally, the higher the temperature, the greater the amount of liquid phase in the slag, and the higher the solubility of the modifier in the slag. Therefore, in actual operation, the modifier can be dissolved in the slag with a high yield. .

The temperature of the slag before reforming when the modifier is added may be the predetermined temperature T or higher by heating the slag before reforming at room temperature, or the temperature of the slag before reforming generated in a molten state may be adjusted to the predetermined temperature T. It is good as above. The pre-reforming slag at the predetermined temperature T or higher is in a molten state or in a solid-liquid coexistence state, and contains a liquid phase. The ratio of the liquid phase in this state is preferably 50% by mass or more because high fluidity is exhibited and reforming by a reforming agent described later progresses rapidly.

As the modifier to be added to the pre-modification slag, one having a SiO ₂ content of 30% by mass or more and being dissolved in the liquid phase of the pre-modification slag is used. Thereby, the elution of boron from the modified slag can be effectively suppressed. The SiO ₂ content in the modifier is preferably 50% by mass or more, more preferably 70% by mass or more. The post-modification calculated boron concentration _C2 described above corresponds to the boron concentration in the glass phase present in the modified slag at room temperature. Then, the boron-containing slag having a low boron concentration in the glass phase has a sufficiently small boron elution amount and satisfies the environmental standard value or voluntary standard value. Therefore, by adding the modifier, it dissolves in the liquid phase of the slag before modification, widens the liquid phase range of the slag, and the calculated boron concentration _C2 after modification becomes equal to or less than the predetermined threshold value C, so that the glass phase The concentration of boron in the slag is lowered, and the elution of boron from the modified slag is suppressed.
As the modifier, waste glass or stone can be used. In general, the melting point of crystalline SiO ₂ is 1700 ° C. or higher, but since each component including SiO ₂ in waste glass is not crystallized, it melts when it is added to high-temperature slag and enters the liquid phase. Dissolves easily. In addition, it is thought that the melting point of roselite is lower than that of silica sand containing crystalline _SiO2 as a main component because it contains Al ₂ O ₃ in an amount of 10% by mass or more. Dissolves easily.
Although the shape of the modifier is not particularly limited, it is preferably in the form of powder or particles in terms of rapid modification. Moreover, in order to suppress the temperature drop of the slag before reforming due to the addition of the reforming material, it is preferable to heat the reforming material in advance.
After the modifier is added to the slag before modification, it is preferable to stir or flow the slag in order to progress the modification uniformly and rapidly.

In addition, the pre-reforming slag in which the pre-reforming calculated boron concentration C ₁ calculated by the equilibrium calculation described above is equal to or lower than the predetermined threshold value C is subjected to other tests and treatments without adding a modifier. Can be reused or final disposed of.

In the first embodiment, the modified slag containing the prepared liquid phase is poured in a thin layer, and the cooling rate at the center in the thickness direction of the thin layer is 10 ° C./min or more from the predetermined temperature T to 1000 ° C. Cool until
By pouring the modified slag in a thin layer, the entire modified slag can be cooled at a high speed, and the stability of boron contained in the generated glass phase is increased, and the productivity is improved. The thickness of the thin layer is preferably 70 mm or less, more preferably 50 mm or less, in order to obtain a high cooling rate. On the other hand, the thickness of the thin layer is preferably 5 mm or more in order to reduce the area required for cooling.
At that time, by setting the cooling rate to 1000° C. at 10° C./min or more, the stability of boron contained in the generated glass phase is enhanced, and the elution of boron from the modified slag is suppressed. The cooling rate is preferably 20° C./min or higher, more preferably 30° C./min or higher.

The first embodiment can be suitably applied when the boron content of the slag before reforming exceeds 0.15% by mass. Slag with a boron content of more than 0.15% by mass often fails the boron elution determination test, but according to the first embodiment, the elution of boron is suppressed and the environmental standard value or voluntary standard value is satisfied. This is because it can be

[Manufacturing method for civil engineering and construction materials]
A method for producing a civil engineering and construction material according to a second embodiment of the present invention (hereinafter sometimes simply referred to as a “second embodiment”) is a modification of the boron-containing slag according to the first embodiment described above. The modified slag obtained by the method is used as the material.

In the second embodiment, it is preferable to adjust the particle size of the boron-containing substance whose boron elution satisfies the environmental standard according to the use of civil engineering and construction materials such as roadbed materials and soil improvement materials. An example of particle size adjustment is crushing or sieving the boron-containing material to a size of 40 mm or less when the boron-containing material is used as a roadbed material.

[Boron-containing modified slag]
The modified slag according to the third embodiment of the present invention (hereinafter sometimes simply referred to as "third embodiment") is composed of boron-containing slag containing more than 0.15% by mass of boron and 30% by mass of _SiO2 % or more and is dissolved in the liquid phase of the slag at a predetermined temperature T within the range of 1100 ° C. to 1200 ° C. calculated by equilibrium calculation based on the composition of the slag. A modified slag having a boron concentration and a SiO ₂ concentration in the liquid phase at the predetermined temperature T of 1.0% by mass or less and 25% by mass or more, respectively, and specified in Notification No. 46 of the Environment Agency It is characterized in that the amount of eluted boron is 1 mg/L or less in an elution test.

As described above, slag with a boron content of more than 0.15% by mass has a large amount of boron elution, and often fails the boron elution determination test. However, the material subjected to the modification treatment according to the above-described first embodiment can suppress the elution of boron and satisfy environmental standard values or voluntary standard values. The effect of the modification treatment is greater in slag with a boron content of 0.16% by mass or more, even greater in slags with a boron content of 0.18% by mass or more, and significantly greater in slags with a boron content of 0.20% by mass or more. can do.

As for the equilibrium calculation conditions and the like in the third embodiment, those described in the first embodiment can be adopted. In the modified slag according to the third embodiment, if the SiO ₂ concentration in the liquid phase at the predetermined temperature T is 25% by mass or more, the elution amount of boron is small. More preferably, the SiO ₂ concentration is 30% by mass or more.

In the third embodiment, the amount of eluted boron is 1 mg/L or less according to the elution test specified in Notification No. 46 of the Environment Agency. Although the amount of boron contained is large, the amount of eluted boron is small, so the third embodiment is useful in that it can expand the range of slag that can be reused as a material for civil engineering and construction. The boron elution amount is preferably 0.9 mg/L or less, more preferably 0.8 mg/L or less.

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

[Example 1]
Slag having the composition shown in Table 1 was prepared as the boron-containing slag. This slag is normally generated in the metal smelting process. The composition of slag shown in Table 1 is estimated from normal operating conditions.

This composition was input to the thermodynamic equilibrium calculation software FactSage 7.2, and the liquid phase composition at 1150° C., which is within the temperature range where the slag is in a solid-liquid coexistence state, was set as a predetermined temperature T, and the liquid phase composition at this temperature was calculated. FToxide was used for the database of FactSage 7.2. Considering the cooling rate during normal operation, the threshold value C for slag boron elution determination was set to 0.8% by mass.

The calculated pre-reforming boron concentration _C1 was 1.4% by mass, which exceeded the threshold value C. When the amount of boron eluted from this slag was measured by the elution test specified in Notification No. 46 of the Environment Agency, it was confirmed that the elution of boron exceeded the voluntary standard value. Voluntary standard values can be set equal to or lower than the publicly determined standard values for each application. A publicly defined reference value is, for example, 1 mg/L according to Notification No. 46 of the Environment Agency.

Next, waste glass was added as a modifier to the molten slag (at a temperature of 1400° C.) and stirred to prepare a modified slag. Based on the composition of the modified slag, the calculated boron concentration _C2 after reforming at a predetermined temperature T (1150 ° C.) calculated by equilibrium calculation is 0.7 mass%, and the threshold value C (0.8 mass%) It became the following. Next, the modified slag was poured into a thin layer of 50 mm thickness on an iron plate of 20 mm thickness, cooled to 1000° C. at a cooling rate of 30° C./min, and solidified. The solidified slag was allowed to stand on an iron plate for about 3 hours, and after it was completely solidified, the slag was collected and crushed to a size of 40 mm or less. When the amount of boron eluted from the crushed slag was measured by the elution test specified in Notification No. 46 of the Environment Agency, it was confirmed that it was below the voluntary standard value.

[Example 2]
A method for modifying boron-containing slag according to Example 2 was carried out in the same manner as in Example 1, except that a mixture of pyroxene and quicklime at a mass ratio of 100:8 was used as the modifier. When the amount of boron eluted from the modified slag was measured by the elution test specified in Notification No. 46 of the Environment Agency, it was confirmed that it was below the voluntary standard value.

[Comparative Example 1]
In order to confirm the effect of adding the modifier, the boron-containing slag modification method according to Comparative Example 1 was performed in the same manner as in Example 1, except that the modifier was not added. When the amount of boron eluted from the modified slag was measured by the elution test specified in Notification No. 46 of the Environment Agency, it was confirmed that the elution of boron exceeded the voluntary standard value.

[Comparative Example 2]
In order to confirm the change in the boron elution amount due to the cooling rate, the same procedure as in Example 2 was performed except that the cooling rate of the central part in the thickness direction of the thin layer was slowed to 5 ° C./min in the temperature range from 1250 ° C. to 1000 ° C. Then, the boron-containing slag reforming method according to Comparative Example 2 was performed. When the amount of boron eluted from the modified slag was measured by the elution test specified in Notification No. 46 of the Environment Agency, it was confirmed that the elution of boron exceeded the voluntary standard value.

[Comparative Example 3]
A boron-containing slag reforming method according to Comparative Example 3 was performed in the same manner as in Example 1, except that the calculated boron concentration _C2 after reforming was set to 1.1% by mass, which exceeds the threshold value C. When the amount of boron eluted from the modified slag was measured by the elution test specified in Notification No. 46 of the Environment Agency, it was confirmed that the elution of boron exceeded the voluntary standard value.

Table 2 summarizes the treatment conditions and the determination results of the boron elution amount in each example, comparative example, and reference example.

From Table 2, the boron-containing slag with a calculated boron concentration C ₁ before reforming exceeding a predetermined threshold C is modified so that the boron concentration in the liquid phase at a predetermined temperature T calculated by equilibrium calculation is below the threshold C. In the slag of the example in which the material was added and the cooling rate to 1000°C was set to 10°C/min or more, the measured value of the boron elution amount was below the voluntary standard value, indicating that the elution of boron was suppressed. In contrast, the slag according to Comparative Example 1, in which the modifier was not added in the molten state, still retains a large amount of eluted boron even when cooled at a high speed.

Further, from the comparison between Example 2 and Comparative Example 2, even if the slag is modified so that the calculated boron concentration _C2 after modification is equal to or lower than the threshold value C, when it is gradually cooled from the molten state, It can be seen that the boron elution amount increases. From this result, in the first embodiment, when determining the necessity of reforming the slag before reforming, which has a slow cooling rate from the molten state, the stability of boron contained in the glass phase is low. Therefore, it can be said that the threshold value C needs to be set low.

ADVANTAGE OF THE INVENTION According to this invention, the method of suppressing the elution of boron from boron-containing slag simply and economically is provided. For this reason, it was not possible to reuse the boron-containing slag because the amount of eluted boron did not need to be subjected to unnecessary elution suppression treatment, and the amount of eluted boron exceeded the environmental standard. The present invention is characterized in that the boron-containing substance can be reused, and that the boron-containing substance, which had to be treated separately at the time of final disposal for the same reason, can be easily finalized by omitting the treatment. is useful.

Claims (6)

A method for reforming a boron-containing slag, comprising:
Calculating the calculated boron concentration before reforming C1, which is the boron concentration in _the liquid phase at a predetermined temperature T at which the slag is in a solid-liquid coexistence state, by equilibrium calculation based on the composition of the slag before reforming;
With respect to the pre-reforming slag in which the calculated boron concentration C ₁ before reforming exceeds a predetermined threshold value C, 30% by mass or more of SiO ₂ is contained at the predetermined temperature T or higher, and at the predetermined temperature T A modifier that dissolves in the liquid phase of the slag is added to modify it, and the calculated boron after modification in the liquid phase at a predetermined temperature T in a solid-liquid coexistence state is calculated by equilibrium calculation based on the composition. Preparing a modified slag whose concentration _C2 is equal to or lower than the predetermined threshold value C, and
Boron-containing slag, including pouring the modified slag in a thin layer and cooling the central portion in the thickness direction of the thin layer so that the cooling rate is 10 ° C./min or more from the predetermined temperature T to 1000 ° C. modification method.
However, the predetermined threshold value C is a value selected from the range of 0.5% by mass to 1.0% by mass, and the predetermined temperature T is calculated from the powder X-ray diffraction measurement result of the slag before reforming. The temperature is ±50° C. at which the proportion of the liquid phase in the solid-liquid coexistence state calculated by the equilibrium calculation agrees with the proportion of the glass phase present in the slag at room temperature. The method for reforming boron-containing slag according to claim 1, wherein the predetermined temperature T is 1100°C to 1200°C. The method for reforming boron-containing slag according to claim 1 or 2, wherein the reforming material is waste glass. The method for modifying boron-containing slag according to claim 1 or 2, wherein the modifier contains 50% by mass or more of pyrophyllite. The method for reforming boron-containing slag according to any one of claims 1 to 4, wherein the boron content of the slag before reforming exceeds 0.15% by mass. A method for producing a material for civil engineering and construction, characterized in that the slag obtained by the method for modifying boron-containing slag according to any one of claims 1 to 5 is used as a material. How materials are made.