Method for producing granulated solidified material, granulated solidified material, and method for utilizing granulated solidified material

Abstract

This invention provides a technology for easily obtaining granulated solidified material from raw materials containing at least one of incinerated ash or inorganic sludge. [Solution] A method for producing granulated solidified material, comprising: a granulation step of mixing a solidifying agent with a raw material containing at least one of incinerated ash or inorganic sludge and kneading it to make the raw material coarse; and a solidification step of letting the coarsely granulated raw material stand to solidify.

Description

[Technical Field]

[0001] This invention relates to a method for producing granulated solidified material, granulated solidified material, and a method for utilizing granulated solidified material. [Background technology]

[0002] There are studies underway to utilize raw materials such as incinerated ash and inorganic sludge as materials for civil engineering and construction. For example, Patent Document 1 discloses a method for efficiently manufacturing molded products using incinerated ash as a raw material, which contributes to reducing the amount of waste sent to landfills. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2003-211137 [Overview of the project] [Problems that the invention aims to solve]

[0004] One embodiment of the present invention aims to easily obtain granulated solidified material from raw materials containing at least one of incinerated ash or inorganic sludge. [Means for solving the problem]

[0005] A granulation process in which a solidifying agent is mixed and kneaded with a raw material containing at least one of incinerated ash or inorganic sludge to coarsely granulate the raw material and obtain coarse granules, A method for producing a granulated solid product, comprising a solidification step of allowing the aforementioned coarse granules to stand and solidify in order to obtain a granulated solid product.

[0006] A second aspect of the present invention is: The method for producing granulated solidified material according to the first embodiment is as follows: In the granulation step, the amount of water is adjusted so that the water content of the raw material is 30% by mass or more and 50% by mass or less.

[0007] A third aspect of the present invention is: The granulation process described above is: A first kneading step involves adding water to the raw materials and kneading them to adjust the moisture content of the raw materials, A method for producing a granulated solidified product according to the first or second embodiment, comprising a second mixing step of mixing the solidifying agent with the raw materials after the first mixing step.

[0008] A fourth aspect of the present invention is: The method for producing granulated solidified material according to any one of the first to third embodiments described above is to produce granulated solidified material in which no external pressure is applied to the coarse granules in the solidification step.

[0009] A fifth aspect of the present invention is: The method for producing granulated solidified material according to any one of the first to fourth embodiments, wherein the solidification step involves letting the raw materials stand and solidify until the moisture content of the coarse granules decreases by 1% by mass or more from the state before standing.

[0010] A sixth aspect of the present invention is: The method for producing a granulated solidified product according to any one of the first to fifth embodiments is to mix a magnesium-based solidifying agent as the solidifying agent in the granulation step.

[0011] A seventh aspect of the present invention is: The granulation step involves adding an insolubilizing agent to the raw material, and is a method for producing granulated solidified material according to any one of the first to sixth embodiments described above.

[0012] An eighth aspect of the present invention is: The granulation step involves adding a hardening accelerator to the raw material, and is a method for producing granulated solidified material according to any one of the first to seventh embodiments described above.

[0013] A ninth aspect of the present invention is: The aforementioned raw material further contains glass shards, The method for producing granulated solidified material according to any one of the first to eighth embodiments described above, wherein the total ratio of incinerated ash and inorganic sludge in the raw materials is 50% by mass or more.

[0014] The tenth aspect of the present invention is In the granulation step, kneading is performed using a paddle mixer, and it is a method for producing a granulated solidified product according to any one of the first to ninth aspects described above.

[0015] The eleventh aspect of the present invention is In the solidification step, the coarse particles are allowed to stand and solidified at normal temperature in an air atmosphere, and it is a method for producing a granulated solidified product according to any one of the first to tenth aspects described above.

[0016] The twelfth aspect of the present invention is A granulated solidified product containing at least one of incineration ash or inorganic sludge as a raw material and a solidifying agent, having a moisture content of 29% by mass or more and 49% by mass or less, and having a cone index of 400 kN / m 2 or more, which is a granulated solidified product.

[0017] The thirteenth aspect of the present invention is When sieved with a sieve having a mesh size of 40 mm, there is no oversize, and when sieved with a sieve having a mesh size of 37.5 mm, the undersize is 95% by mass or more and 100% by mass or less of the whole, which is the granulated solidified product according to the twelfth aspect described above.

[0018] The fourteenth aspect of the present invention is having a median diameter D50 of 0.30 mm or more and 6.50 mm or less, which is the granulated solidified product according to the twelfth or thirteenth aspect described above.

[0019] The fifteenth aspect of the present invention is a granulation step of mixing a solidifying agent with a raw material containing at least one of incineration ash or inorganic sludge, kneading the mixture, and coarsening the raw material to obtain coarse particles, a solidification step of allowing the coarse particles to stand and solidify to obtain a granulated solidified product, and a utilization step of using the granulated solidified product as a civil engineering material, which is a method for using a granulated solidified product.

Advantages of the Invention

[0020] According to one embodiment of the present invention, granulated solidified material can be easily obtained from a raw material containing at least one of incinerated ash or inorganic sludge. [Brief explanation of the drawing]

[0021] [Figure 1] Figure 1 is a flowchart showing an example of a method for producing granulated solidified material according to the first embodiment of the present invention. [Figure 2] Figure 2 shows the particle size distribution diagram of the raw material and granulated solidified product according to an embodiment of the present invention. [Modes for carrying out the invention]

[0022] [Details of the Embodiments of the Invention] One embodiment of the present invention will be described below with reference to the drawings. However, the present invention is not limited to these examples and is intended to include all modifications within the meaning and scope equivalent to the claims, as shown in the claims.

[0023] In this specification, "A to B" means a numerical range of "A or greater and B or less".

[0024] <First Embodiment of the Invention> (1) Method for producing granulated solidified material First, the method for producing the granulated solidified product of this embodiment will be described. In this embodiment, the granulated solidified product is obtained by granulating and solidifying a raw material containing at least one of incinerated ash or inorganic sludge. The raw material of this embodiment, for example, consists of fine particles with a particle size of 1 mm or less, accounting for 50% or more by mass of the total, which easily generates dust and is difficult to handle. By granulating and solidifying such a raw material, dust generation can be suppressed and handling can be improved.

[0025] Figure 1 is a flowchart showing an example of a method for manufacturing granulated solidified material according to this embodiment. As shown in Figure 1, the method for manufacturing granulated solidified material according to this embodiment includes, for example, a granulation step S100 and a solidification step S200. Furthermore, the granulation step S100 includes a first kneading step S110 and a second kneading step S120.

[0026] The raw materials used in this embodiment include at least one of incinerated ash or inorganic sludge, and may also include glass scraps. Incineration ash refers to ash containing, for example, fly ash (soot) contained in exhaust gas generated from an incinerator, and combustion residue (bottom ash) discharged from the bottom of the incinerator. Inorganic sludge refers to sludge mainly composed of inorganic materials generated in the wastewater treatment process or construction work. Glass scraps refer to, for example, crushed industrial glass, and in this embodiment, the case in which glass scraps obtained by peeling and crushing the cover glass of a solar panel are used will be described. From the viewpoint of facilitating granulation and solidification, it is preferable that the total ratio of incinerated ash and inorganic sludge in the raw materials of this embodiment is 50% by mass or more. Furthermore, if the raw materials include glass scraps, it is preferable that the ratio of glass scraps is less than 50% by mass, more preferably 40% by mass or less, and even more preferably 10% by mass or less.

[0027] The granulation process S100 is a process in which a solidifying agent is mixed with the raw material and kneaded to coarseen the raw material and obtain coarse granules. By coarsening the raw material, the proportion of fine particles with a particle size of 1 mm or less is reduced (for example, to less than 50% by mass), thereby suppressing dust generation and improving handling. As the solidifying agent, for example, cement-based solidifying agents such as Portland cement and blast furnace cement, calcium-based solidifying agents such as calcium sulfate, magnesium-based solidifying agents such as magnesium oxide, and ground improvement materials can be used. In the granulation process S100, it is particularly preferable to use a magnesium-based solidifying agent. This makes it possible to suppress the leaching of hexavalent chromium, fluorine, arsenic, boron, etc. contained in the raw material and solidifying agent.

[0028] The granulation process S100 is preferably divided into a first kneading process S110 and a second kneading process S120. As shown in Figure 1, in this embodiment, in the first kneading process S110, water and an insolubilizing agent are added to the raw material and kneaded, and in the second kneading process S120, a solidifying agent and a hardening accelerator are added to the kneaded product obtained in the first kneading process S110 and kneaded.

[0029] The first mixing step S110 is a step in which, for example, water is added to the raw material and mixed to adjust the moisture content of the raw material. By adjusting the moisture content of the raw material in this way before mixing in the solidifying agent, the granulation of the raw material is facilitated. The mixing in the first mixing step S110 can be carried out using, for example, a paddle mixer.

[0030] In the granulation process S100, it is preferable to adjust the moisture content of the raw material so that its moisture content is between 30% by mass and 50% by mass. By setting the moisture content of the raw material to 30% by mass or more, the hydration reaction of cement is promoted, and hydrates are sufficiently produced, making it easier to granulate the raw material. Furthermore, by setting the moisture content of the raw material to 50% by mass or less, the solidification of the raw material proceeds more easily in subsequent processes. The moisture content of the raw material referred to here refers to the moisture content of the raw material at the final stage in the granulation process S100 (i.e., the state after all substances added to the raw material, such as solidifying agents, immobilizing agents, and hardening accelerators, have been added in the granulation process S100). Therefore, when water is added to the raw material in the first mixing process S110, it is preferable to adjust the moisture content so that the moisture content of the raw material after the addition of solidifying agents and hardening accelerators in the second mixing process S120 falls within the above range.

[0031] In the granulation process S100, it is preferable to further add an immobilizing agent to the raw materials. This suppresses the leaching of heavy metals such as hexavalent chromium, fluorine, arsenic, boron, and lead contained in the raw materials and solidifying agents. Examples of immobilizing agents include iron chloride, ferrous sulfate, aluminum sulfate, and PAC (polyaluminum chloride). From the viewpoint of efficiently suppressing leaching, it is preferable to add the immobilizing agent in the first kneading process S110.

[0032] The second mixing step S120 is a step in which a solidifying agent is mixed with the raw material after the first mixing step S110, for example, and then mixed. In this embodiment, since the moisture content of the raw material has been adjusted in advance, granulation proceeds more easily after mixing with the solidifying agent. The mixing in the second mixing step S120 can be carried out using a paddle mixer, similar to the first mixing step S110.

[0033] In the granulation process S100, a hardening accelerator can be added to the raw material. This makes the granulation of the raw material easier. For example, aluminum sulfate or magnesium sulfate can be used as the hardening accelerator. From the viewpoint of efficiently obtaining the granulation-accelerating effect, it is preferable to add the hardening accelerator in the second kneading process S120.

[0034] The solidification process S200 is a process in which the coarse granules obtained in the granulation process S100 are left to stand and cured to solidify. In this embodiment, the solidification process S200 does not require the raw material to be compressed or molded, as described in Patent Document 1, but only requires it to be left to stand. In other words, solidification can be completed without applying external pressure to the coarse granules. Specifically, the coarse granules can be piled up and left to stand in an atmospheric environment at room temperature. It is preferable that the place where the coarse granules are left to stand is an environment where they do not come into contact with water. The standing time is preferably one day or more, more preferably three days or more, and particularly preferably one week or more.

[0035] In the solidification process S200, it is preferable to allow the raw materials to solidify by letting them stand until their moisture content decreases by 1% to 10% by mass from their state before standing. By reducing the moisture content by 1% by mass or more, a sufficiently solidified granulated material can be obtained. Furthermore, by reducing the moisture content by 10% by mass or less, the granulated material can maintain a moderately moist state, thereby improving handling.

[0036] Through the above process, coarse particles are obtained from the raw material, allowing for easy production of granulated solidified material in the subsequent solidification process S200. Since the granulated solidified material is obtained through coarse particles that are larger than the raw material, dust generation is suppressed and handling is improved.

[0037] (2) Granulated solidified product Next, the characteristics of the granulated solidified product of this embodiment obtained in (1) will be described. The granulated solidified product of this embodiment contains a raw material which includes at least one of incinerated ash or inorganic sludge, and a cement-based solidifying agent (e.g., blast furnace cement) or a magnesium-based solidifying agent (e.g., magnesium oxide).

[0038] The moisture content of the granulated solidified material is between 29% by mass and 49% by mass. Maintaining this moisture content range suppresses dust generation and improves handling. Furthermore, the cone index (see JIS A 1228) of the granulated solidified material is 400 kN / m³. 2 That concludes the explanation. In short, the granulated solidified material meets the standards for Type 3 improved soil and can be suitably used, for example, as backfill material. The cone index of the granulated solidified material is 800 kN / m 2 It is preferable that the above conditions are met, in which case the standards for Type 2 improved soil are satisfied.

[0039] Preferably, when the granulated solidified material is sieved using a sieve with a mesh size of 40 mm, there is no material above the sieve, and when sieved using a sieve with a mesh size of 37.5 mm, the material below the sieve is between 95% and 100% by mass of the total. This means that the granulated solidified material meets the standards for crusher run C-40 material. The sieving test method can be carried out in accordance with, for example, JIS A 1102.

[0040] The granulated solidified material preferably has a median diameter D50 of 0.30 mm to 6.50 mm, and more preferably 1.00 mm to 4.75 mm. By keeping the median diameter D50 within the above range, dust generation can be suppressed and handling can be improved. Furthermore, the particle size distribution of the granulated solidified material (histogram with particle size on the horizontal axis and frequency on the vertical axis) preferably has two or more peaks in the particle size range of 0.60 to 4.75 mm. This can further improve the cone index.

[0041] (3) Method of using granulated solidified material The granulated solidified material obtained by the present invention can also be used as a civil engineering material such as a cover material and a backfill material. In this case, for example, after performing the granulation process S100 and the solidification process S200 described above, the obtained granulated solidified material can be used as a civil engineering material. As described above, the granulated solidified material meets the standards for Type 3 improved soil (or Type 2 improved soil), and is therefore suitable for use as a civil engineering material.

[0042] <Other embodiments of the present invention> Although embodiments of the present invention have been specifically described above, the present invention is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the invention.

[0043] For example, in the above embodiment, the case was described in which, in the first mixing step S110, water, an insolubilizer, and a hardening accelerator are added to the raw materials and mixed, and in the second mixing step S120, a solidifying agent is added to the raw materials and mixed. However, it is not necessary to add all of these to the raw materials. Additives other than the solidifying agent (water, insolubilizer, hardening accelerator) can be omitted.

[0044] Furthermore, in the above-described embodiment, the granulation process S100 was described in two stages: a first kneading process S110 and a second kneading process S120. However, it is not necessary to divide it into two stages. For example, it is possible to perform the granulation process S100 in one stage using a single paddle mixer. However, from the viewpoint of efficiently carrying out granulation, it is preferable to divide the granulation process S100 into two stages, as in the above-described embodiment. In this case as well, two paddle mixers can be used continuously, one for moisture adjustment and the other for granulation. [Examples]

[0045] Next, embodiments of the present invention will be described. These embodiments are examples of the present invention, and the present invention is not limited to these embodiments.

[0046] <Condition 1> First, a mixture of 110.62 tons of incinerator ash (90% by mass of the total raw materials), 9.54 tons of inorganic sludge (9% by mass of the total raw materials), and 1.42 tons of glass waste (1% by mass of the total raw materials) was prepared as raw materials. The initial moisture content of the raw materials, measured using a heat-drying type moisture meter, was 18% by mass, and the median diameter D50 was 0.4 mm. A backhoe was used to mix the raw materials.

[0047] The raw materials were fed into the hopper at a rate of 10 tons / hr, and scrap metal and other impurities were removed from the raw materials using a suspended magnetic separator.

[0048] Water equivalent to 5% by mass of the raw materials was added, and then ferrous sulfate (3% by mass) and aluminum sulfate (2% by mass) were added as immobilizers to perform the first mixing process S110. Mixing was carried out using a paddle mixer (ST-200, manufactured by Kiko Co., Ltd.). The internal capacity of the paddle mixer was approximately 6 m³. 3 The drive shaft rotation speed was set to 47 rpm, and the residence time to 9 min.

[0049] Subsequently, blast furnace cement (Type B) was added to the raw materials as a solidifying agent in an amount equivalent to 10% by mass of the raw materials, and the second mixing process S120 was carried out. The same type of paddle mixer as in the first mixing process S110 was used for mixing, and the operating conditions were also the same.

[0050] The moisture content of the coarse grain obtained after the second mixing process S120 was 28% by mass, and the median diameter D50 was 0.7 mm.

[0051] The granulated coarse material was placed in a mound about 1 meter high and allowed to solidify for 7 days in an air atmosphere at room temperature.

[0052] After the solidification process S200, the moisture content of the granulated solidified material was 27% by mass, and the cone index was 1043 kN / m³. 2 That was the case.

[0053] <Condition 2> In the first mixing step S110, granulation and solidification were carried out under the same conditions as in Condition 1, except that water equivalent to 10% by mass of the raw material was added.

[0054] The moisture content of the coarse grain obtained after the second mixing process S120 was 33% by mass, and the median diameter D50 was 1.7 mm.

[0055] After the solidification process S200, the moisture content of the granulated solidified material was 32% by mass, and the cone index was 1120 kN / m³. 2 That was the case.

[0056] <Condition 3> In the first mixing step S110, granulation and solidification were carried out under the same conditions as in Condition 1, except that water equivalent to 20% by mass of the raw material was added.

[0057] The moisture content of the coarse grain obtained after the second mixing process S120 was 42% by mass, and the median diameter D50 was 6.3 mm.

[0058] After the solidification process S200, the moisture content of the granulated solidified material was 41% by mass, and the cone index was 1478 kN / m³. 2 That was the case.

[0059] <Condition 4> In the first mixing step S110, granulation and solidification were carried out under the same conditions as in Condition 1, except that water equivalent to 15% by mass of the raw material was added.

[0060] The moisture content of the coarse grain obtained after the second mixing process S120 was 37% by mass, and the median diameter D50 was 2.2 mm.

[0061] After the solidification process S200, the moisture content of the granulated solidified material was 36% by mass, and the cone index was 1211 kN / m³. 2 That was the case.

[0062] <Condition 5> In the first mixing step S110, granulation and solidification were carried out under the same conditions as in Condition 1, except that the raw material supply rate was set to 20 t / hr and water was added in an amount equivalent to 10% by mass of the raw material.

[0063] The moisture content of the coarse grain obtained after the second mixing process S120 was 33% by mass, and the median diameter D50 was 1.8 mm.

[0064] The water content of the granulated solidified product after performing the solidification step S200 was 32% by mass, and the cone index was 1471 kN / m 2 It was as follows.

[0065] <Condition 6> In the first kneading step S110, granulation and solidification were performed in the same manner as in Condition 1, except that the supply rate of the raw material was 40 t / hr and water was added at 10% by mass of the raw material.

[0066] The water content of the coarse particles obtained after performing the second kneading step S120 was 33% by mass, and the median diameter D50 was 1.7 mm.

[0067] The water content of the granulated solidified product after performing the solidification step S200 was 32% by mass, and the cone index was 1433 kN / m 2 It was as follows.

[0068] Also, for comparison, the cone index was measured in the state of the raw material, and the result was 318 kN / m 2 It was as follows.

[0069] The above results are summarized and shown in Table 1.

[0070] [Table 1]

[0071] As shown in Table 1, it was confirmed that granulated solidified products with a cone index of 800 kN / m 2 or higher could be easily obtained in all of Conditions 1 to 6.

[0072] <Condition 7> In Condition 7, as the raw material, a mixture of 2 kg of burned shells (80% by mass of the total raw material) and 0.5 kg of glass waste (20% by mass of the total raw material) was prepared. The water content of the raw material in the initial state measured using a heat drying type moisture meter was 12% by mass, and the median diameter D50 was 1. The mixing of the raw materials was carried out manually in an experimental vat.

[0073] Water equivalent to 20% by mass of the raw material was added, and the first mixing process S110 was carried out. Mixing was performed using a tabletop pan-type granulator (AS ONE, PZ-02R). The internal capacity was approximately 8.4L, the drive shaft rotation speed was 50 rpm, the inclination angle was 45°, and the processing time was 9 minutes.

[0074] Subsequently, blast furnace cement (Type B) was added to the raw materials as a solidifying agent in an amount equivalent to 10% by mass of the raw materials, and the second mixing process S120 was carried out. The mixing was performed using the same type of granulator as in the first mixing process S110, and the operating conditions were also the same.

[0075] The moisture content of the coarse grain obtained after the second mixing process S120 was 30% by mass, and the median diameter D50 was 1.8 mm.

[0076] The granulated coarse material was placed in a mound about 10 cm high and allowed to solidify for 7 days in an air atmosphere at room temperature.

[0077] After the solidification process S200, the moisture content of the granulated solidified material was 30% by mass, and the cone index was 1665 kN / m³. 2 That was the case.

[0078] <Condition 8> Granulation and solidification were carried out under the same conditions as in Condition 7, except that the amount of water added was 25% by mass of the raw materials, and blast furnace cement (Type B) was added at 20% by mass of the raw materials.

[0079] The moisture content of the coarse grain obtained after the second mixing process S120 was 30% by mass, and the median diameter D50 was 1.8 mm.

[0080] After the solidification process S200, the moisture content of the granulated solidified material was 30% by mass, and the cone index was 1897 kN / m³. 2 That was the case.

[0081] <Condition 9> Under condition 9, a mixture of 1.5 kg of incinerator ash (60% by mass of the total raw materials) and 1.0 kg of glass waste (40% by mass of the total raw materials) was prepared as the raw materials. The initial moisture content of the raw materials, measured using a heat-drying type moisture meter, was 10% by mass, and the median diameter D50 was 2.4 mm. The subsequent process was carried out in the same manner as under condition 7, except that the amount of water added was 25% by mass of the raw materials.

[0082] The moisture content of the coarse grain obtained after the second mixing process S120 was 30% by mass, and the median diameter D50 was 1.8 mm.

[0083] After the solidification process S200, the moisture content of the granulated solidified material was 30% by mass, and the cone index was 1678 kN / m³. 2 That was the case.

[0084] <Condition 10> Granulation and solidification were carried out under the same conditions as in Condition 9, except that the amount of water added was 30% by mass of the raw materials, and blast furnace cement (Type B) was added at 20% by mass of the raw materials.

[0085] The moisture content of the coarse grain obtained after the second mixing process S120 was 30% by mass, and the median diameter D50 was 1.8 mm.

[0086] After the solidification process S200, the moisture content of the granulated solidified material was 30% by mass, and the cone index was 1923 kN / m³. 2 That was the case.

[0087] The results above are summarized in Table 2.

[0088] [Table 2]

[0089] As shown in Table 2, even with raw materials consisting of 80% by mass of incinerator ash and 20% by mass of glass scraps, or 60% by mass of incinerator ash and 40% by mass of glass scraps, the cone index was 800 kN / m³. 2 We confirmed that the above-mentioned granulated solidified material can be easily obtained.

[0090] <Particle size distribution measurement> The raw materials and the granulated solidified materials obtained under conditions 1 to 6 were sieved in accordance with JIS A 1102, and the particle size distribution was measured. The results are shown in Figure 2. In Figure 2, the percentage of water indicated to the right of each condition represents the amount of water added in the first mixing step S110.

[0091] As shown in Figure 2, in the raw material state, the amount of fine particles with a particle size of 1 mm or less was 50% by mass or more. However, under conditions 2 to 6, where the moisture content in the second kneading step S120 was 30% by mass or more and 50% by mass or less (the moisture content of the granulated solidified product was 29% by mass or more and 49% by mass or less), the amount of fine particles with a particle size of 1 mm or less was less than 50% by mass. From the above, it was confirmed that adjusting the moisture content can make the granulation process more efficient.

[0092] <Evaluation of quality and elution> For granulated solidified materials under conditions 1 to 6, and their elution solutions, measurements for hazardous substances (chromium, fluorine, arsenic, cadmium, lead, selenium, mercury, boron, and their compounds) were conducted in accordance with Ministry of the Environment Notifications No. 18 and 19. As a result, it was confirmed that all granulated solidified materials and elution solutions met the soil environmental standards. [Explanation of Symbols]

[0093] S100 Granulation process S110 1st kneading process S120 2nd kneading process S200 Solidification process

Claims

1. A granulation process in which a solidifying agent is mixed and kneaded with a raw material containing at least one of incinerated ash or inorganic sludge to coarsely granulate the raw material and obtain coarse granules, A method for producing a granulated solid product, comprising a solidification step of allowing the coarse granules to stand and solidify in order to obtain a granulated solid product.

2. The method for producing a granulated solidified product according to claim 1, wherein in the granulation step, the amount of water is adjusted so that the water content of the raw material is 30% by mass or more and 50% by mass or less.

3. The granulation process described above is: A first kneading step involves adding water to the raw materials and kneading them to adjust the moisture content of the raw materials. A method for producing a granulated solidified product according to claim 1, comprising a second mixing step of mixing the solidifying agent with the raw materials after the first mixing step.

4. The method for producing a granulated solidified product according to claim 1, wherein no external pressure is applied to the coarse granules in the solidification step.

5. The method for producing a granulated solidified product according to claim 1, wherein in the solidification step, the raw material is allowed to stand and solidify until the moisture content of the coarse granules decreases by 1% by mass or more from the state before standing.

6. The method for producing a granulated solidified product according to claim 1, wherein in the granulation step, a magnesium-based solidifying agent is mixed as the solidifying agent.

7. The method for producing a granulated solidified product according to claim 1, wherein an insolubilizing agent is added to the raw material in the granulation step.

8. The method for producing a granulated solidified product according to claim 1, wherein a hardening accelerator is added to the raw material in the granulation step.

9. The aforementioned raw material further contains glass shards, The method for producing granulated solidified material according to claim 1, wherein the total ratio of incinerated ash and inorganic sludge in the raw materials is 50% by mass or more.

10. The method for producing a granulated solidified product according to claim 1, wherein the granulation step is performed using a paddle mixer.

11. The method for producing a granulated solidified product according to claim 1, wherein the solidification step involves allowing the coarse granules to stand and solidify in an atmospheric environment at room temperature.

12. A granulated solidified product comprising a raw material containing at least one of incinerated ash or inorganic sludge, and a solidifying agent, The moisture content is between 29% by mass and 49% by mass. The cone index is 400 kN / m ２ That concludes the granulated solidified material.

13. When sieving with a sieve with a mesh size of 40 mm, there was no sieve portion remaining. The granulated solidified material according to claim 12, wherein when sieved with a sieve with a mesh opening of 37.5 mm, the portion that remains below the sieve accounts for 95% to 100% of the total mass.

14. The granulated solidified material according to claim 12, wherein the median diameter D50 is 0.30 mm or more and 6.50 mm or less.

15. A granulation process in which a solidifying agent is mixed and kneaded with a raw material containing at least one of incinerated ash or inorganic sludge to coarsely granulate the raw material and obtain coarse granules, A solidification step is performed to allow the coarse granules to stand and solidify in order to obtain a granulated solidified product. A method for utilizing granulated solidified material, comprising a utilization step of utilizing the granulated solidified material as a civil engineering material.

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