JP2002003921A - Method for producing fixed carbonic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformize carbonating reaction in a raw material packed layer in a method for fixing a carbonic acid by blowing gaseous carbon dioxide into the non-carbonated Ca-contained raw material packed layer in a molding flame. SOLUTION: This producing method is characterized in having a process (A1), in which water is added and mixed into the raw material containing the non-carbonated Ca, so that the volume ratio [f/w] of the raw material (f) and the water (w) becomes 4-6, a process (B1), in which the raw material added with moisture in the process (A1) is charged into the molding flask and also, during the charging and/or after the charging, vibration is given to the non- carbonated Ca-contained raw material in the molding flask to form the raw material packed layer, and a process (C1), in which the gaseous carbon dioxide is blown into the raw material packed layer formed in the process (B1). Since the packing degree in the formed raw material packed layer is uniformized, the carbonating reaction quantity at each part in the raw material packed layer is uniformized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to uncarbonated Ca such as waste materials containing CaO and slag generated in a steel manufacturing process.
The present invention relates to a method for producing a carbonized solid obtained by solidifying a contained raw material by a carbonation reaction, and the manufactured carbonized solid is a stone for fishing reef and algae reef, a stone for construction of a rock, a stone for water purification, a stone for water permeability. It can be used for various applications including pavement stone, water-permeable covering block, buried drain block, hydroponic cultivation base material, water purification filter, and water supply container.

[0002]

2. Description of the Related Art As a stone material for reef and algae reefs, which replaces conventional steel products and concrete products, it has been proposed to use a carbonated solidified product obtained by solidifying powdery and granular slag generated in a steelmaking process by a carbonation reaction. Japanese Patent Application Laid-Open Nos. 11-71160 and 11-193516. The carbonated solidified product made from this slag has a porous property with fine pores, and does not cause problems such as an increase in pH of seawater as in concrete products. It can be said that they are suitable for the growth and habitation of algae and marine micro-organisms.

[0003]

As a method for producing a solidified carbonate as described above, a raw material containing uncarbonated Ca such as slag is formed into a block shape or the like, and then placed in a carbon dioxide gas atmosphere, followed by carbonation curing. To produce a carbonated solidified body by:
In order to manufacture a large block, a production method in which an uncarbonated Ca-containing material is filled in a mold and carbon dioxide gas is blown into the material-filled layer to carbonate and solidify the entire packed layer is considered. JP-A-11-71160, JP-A-11-71160
193516 discloses this latter manufacturing method.

[0004] Of the above two types of manufacturing methods, the former is suitable for mass-producing relatively small products, but the molded product is carbonated uniformly from the surface thereof to the inside. Difficult, and in some cases, a dense carbonated layer with a thickness of about several hundred μm is formed on the surface layer of the molded product,
In some cases, the inside of the molded product is not carbonated. On the other hand, the latter production method is suitable for causing a carbonation reaction up to the inside of the raw material layer and has an advantage that a large block can be produced. However, the above-mentioned JP-A-11-71160 and JP-A-11-193516 have the advantage. A raw material is charged and filled in a mold in which a plurality of gas supply pipes (gas supply pipes having gas blowing holes formed at an appropriate pitch) are arranged at the bottom as shown in the official gazette, and the gas supply pipe is charged. In a simple method such as blowing carbon dioxide gas from the surface, the carbonation reaction amount of each part of the packed bed tends to vary. In particular, when the shape of the large block to be manufactured is relatively complicated, it is difficult to uniformly fill the raw material in the mold, and the variation in the amount of carbonation reaction in each part of the packed layer occurs more. Cheap.

[0005] Further, since the above-mentioned carbonized solidified product is produced by reacting uncarbonated Ca-containing raw material (granules) such as slag with carbon dioxide gas, it is inherently a porous material. According to the results of experiments performed by a person, when a carbonation reaction is carried out from the outer surface of the molded body as in the former manufacturing method, closed pores are easily generated inside the molded body. Also, in the case of the latter manufacturing method as shown in Japanese Patent Application Laid-Open No. 71160/1995, the flow of the blown carbon dioxide gas is not uniform, so that closed pores are locally generated. (Solidified portion). When such closed pores are formed in the solidified carbonated body, there is a problem that although the porous body is a porous body, the water permeability is inferior, and the buoyancy in water is increased to reduce the weight of the water. As the use of the carbonated solidified material, in addition to the stone for submersion as shown in the prior art, a material for water-permeable pavement,
Although a water-permeable covering material, a water purification filter, and the like are conceivable, in these applications, it is preferable that the number of closed pores is small and many of the pores are continuous open pores in order to secure water permeability. In addition, even when submerged in order to create an artificial algae reef or the like, it is desirable that the number of closed pores that increase the buoyancy of the stone be as small as possible in order to make it difficult for the tide to flow.

Accordingly, an object of the present invention is to provide a method for producing a carbonized solid by filling a raw material containing uncarbonated Ca in a mold, forming a raw material packed layer, and blowing carbon dioxide gas into the raw material filled layer. A method for producing a solidified carbonized material capable of equalizing the amount of carbonation reaction in each part of the material-filled layer regardless of the shape of the material-filled layer, and preferably forming a large number of continuous open pores in the carbonized material. Is to provide.

[0007]

The features of the present invention for solving such a problem are as follows. [1] A powder-granular uncarbonated Ca-containing raw material to which water has been added is filled in a substantially airtight mold having a gas supply part and a gas exhaust part to form a raw material filling layer. By blowing a carbon dioxide gas or a carbon dioxide-containing gas into the layer, the uncarbonated Ca-containing raw material is solidified using calcium carbonate generated by the carbonation reaction of the uncarbonated Ca as a main binder,
In the method for producing a carbonated solidified product, water is added to an uncarbonated Ca-containing raw material so that the volume ratio [f / w] of the uncarbonated Ca-containing raw material f to water w is 4 to 6. A mixing step (A1) and charging the uncarbonated Ca-containing raw material to which water has been added in the step (A1) into the mold, and adding the uncarbonated Ca in the mold during and / or after the charging. (B1) forming a raw material packed layer by applying vibration to the Ca-containing raw material, and blowing (C1) carbon dioxide or a carbon dioxide-containing gas into the raw material packed layer formed in the step (B1). A method for producing a solidified carbonic acid product, comprising:

[2] A raw material-filled layer is formed by filling a powdery and granular uncarbonated Ca-containing raw material with added water in a substantially airtight mold having a gas supply part and a gas exhaust part, By blowing a carbon dioxide gas or a carbon dioxide-containing gas into the raw material packed layer, the uncarbonated Ca-containing raw material is solidified using calcium carbonate generated by the carbonation reaction of the uncarbonated Ca as a main binder to produce a carbonized solid. In the method, a step of adding water and mixing the uncarbonated Ca-containing raw material (A2)
And charging the uncarbonated Ca-containing raw material to which water has been added in the step (A2) into a mold, and during the charging and / or
Alternatively, a raw material-filled layer is formed by applying vibration to the uncarbonated Ca-containing raw material in the mold after charging, and then the volume ratio of the uncarbonated Ca-containing raw material f to water w in the raw material packed layer [f /
(B2) evaporating and removing excess moisture in the raw material packed layer so that w] becomes 4 to 6; and supplying carbon dioxide or a carbon dioxide gas to the raw material packed layer after the step (B2). And a blowing step (C2).

[3] A raw material-filled layer is formed by filling a powdery granular uncarbonated Ca-containing raw material to which water has been added into a substantially airtight mold having a gas supply portion and a gas exhaust portion, By blowing a carbon dioxide gas or a carbon dioxide-containing gas into the raw material packed layer, the uncarbonated Ca-containing raw material is solidified using calcium carbonate generated by the carbonation reaction of the uncarbonated Ca as a main binder to produce a carbonized solid. In the method, a step of adding and mixing water to the uncarbonated Ca-containing raw material (A3)
And charging the uncarbonated Ca-containing raw material to which water has been added in the step (A3) into the mold, and during the charging and / or
Alternatively, a step (B3) of forming a raw material-packed layer by applying vibration while passing non-carbonated Ca and an inert gas through the non-carbonated Ca-containing raw material in the mold after charging, and the step (B3)
(C3) injecting a carbon dioxide gas or a carbon dioxide-containing gas into the raw material packed layer formed by the method (C3).

[4] In the manufacturing method of the above [3], the step (A)
In 3), the uncarbonated Ca-containing material is added to the uncarbonated C
The volume ratio [f / w] of the a-containing raw material f and water w is 3.5 to 6
A method for producing a solid carbonated product, wherein water is added and mixed so that [5] In the manufacturing method according to any one of the above [1] to [4], in step (C1), (C2) or (C3), humidified carbon dioxide gas or carbon dioxide gas-containing gas is blown into the raw material packed bed. A method for producing a solidified carbonated product, characterized in that: [6] In the production method according to any one of the above [1] to [5], in the step (B1), (B2) or (B3), the uncarbonated Ca-containing raw material layer charged in the mold is added. A method for producing a solidified carbonic material, wherein a raw material packed layer is formed by applying vibration while applying pressure from above by a pressure means.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The method for producing a solidified carbonate according to the present invention is characterized in that a substantially granular airtight mold having a gas supply section and a gas exhaust section contains powdered granular uncarbonated Ca containing water. A raw material (hereinafter, simply referred to as “raw material”) is filled to form a raw material packed layer, and a carbon dioxide gas or a gas containing carbon dioxide gas (hereinafter, simply referred to as “carbon dioxide gas”) is blown into the raw material packed layer to obtain uncarbonated gas. In this method, a raw material is solidified using calcium carbonate generated by a carbonation reaction of calcium carbonate as a main binder to obtain a carbonized solid.

In such a method for producing a solidified carbonated material, as a method for uniformizing the raw material filling properties of a raw material filling layer formed in a mold, particularly a raw material filling layer having a relatively complicated shape, for example, It is conceivable to add a large amount of water to the material to improve the slip between the raw material particles, or to fluidize the raw material like a slurry. It is not possible to flow evenly, and as a result, the carbonation reaction in each part of the raw material packed layer becomes uneven, and in extreme cases, carbonation solidification itself becomes impossible.

Therefore, in the first invention of the present application, the amount of water added to the raw material is specified within a specific range, and the raw material in the mold is vibrated when forming the raw material packed layer to thereby form the raw material packed layer. Is made uniform so that a carbon dioxide gas passage is uniformly formed in the entire raw material packed bed. FIG. 1 (a drawing showing a form in a longitudinal section) shows an embodiment of the first invention of the present application. In the figure, reference numeral 1 denotes a form that can be made substantially airtight; Reference numeral 2 denotes a vibrating device (vibration table) that holds the mold 1, a denotes a raw material, and A denotes a raw material filling layer formed inside the mold 1.

At a position near the bottom in the mold 1, gas through holes are formed at substantially equal intervals on substantially the entire surface, and a partition 3 (porous partition) having substantially uniform air permeability is provided on the entire surface. The raw material filling layer A is held on the partition walls 3. The space below the partition 3 constitutes a gas supply side pressure equalizing chamber 4 adjacent to the raw material filling layer A via the partition 3. A gas supply pipe 5 (gas supply unit) for supplying carbon dioxide gas is connected to the gas supply side pressure equalizing chamber 4.

The vibrating device 2 is arranged so as to be in contact with a support table 20 on which the mold 1 is mounted, a plurality of coil springs 21 holding the support table 20, and a lower surface of the support table 20, and the eccentric rotation The material a in the mold 1 placed on the support 20 vibrates by the vibration of the support 20 being transmitted. The vibration device 2
Is not limited to that of the present embodiment.
An apparatus having an appropriate structure capable of giving vibration to the raw material a in the inside can be used. For example, a vibrator such as a rod-shaped vibrator that directly vibrates the raw material layer may be used.

In the first invention of the present application, the step (A1) of adding and mixing water to the raw material a, and the step of adding the water to the raw material a
(B) to form a raw material packed layer A by charging
1) and a step of blowing carbon dioxide gas into the raw material packed layer A (C
1) and First, in the step (A1), water is added to and mixed with the raw materials such that the volume ratio [f / w] of the raw material f to water w is 4 to 6. Here, raw material f and water w
If the volume ratio [f / w] is less than 4, water is excessive, so that a carbon dioxide gas passage cannot be formed uniformly in the raw material packed bed. On the other hand, if the volume ratio [f / w] exceeds 6, the amount of water in the raw material packed layer is too small, so that sufficient packing property cannot be obtained, and the bonding force between the raw material particles is reduced due to the wide particle spacing of the raw material. Resulting in.

Next, in the step (B1), the step (A)
The raw material a to which water has been added according to 1) is charged into the mold 1,
The raw material a is vibrated during and / or after the charging to form the raw material packed layer A. FIG. 1 (a) shows this state. In step (A1), the raw material a to which water has been added in advance is charged into the mold 1, and after this charging, the vibrating device 2 is operated to start the raw material layer. The material is compacted to a uniform filling degree by applying vibrations to form a raw material filled layer A. By regulating the amount of water added to the raw material in a specific range as described above, by vibrating the raw material in the mold when forming the raw material packed layer, the filling property of the raw material packed layer is made uniform, The carbon dioxide gas passage is formed uniformly in the whole layer. The application of the vibration may be performed during the charging of the raw material a into the mold 1, or both during and after the charging.

In the embodiment shown in FIG. 1, a pressing plate 6 serving as a pressing means is placed on an upper portion of the raw material layer charged in the mold 1, and the pressing plate 6 presses the raw material layer from above. Vibration is applied. By using such pressurizing means, it is possible to form the raw material packed layer A having a more uniform filling degree. As the pressurizing means, in the form of a plate or a block as in the present embodiment, in addition to applying pressure to the raw material layer by its own weight, other than applying pressurizing force to the raw material layer by the driving force of the pressurizing device May be.

The use of the above-mentioned pressurizing means is also advantageous in adjusting the bulk density of the raw material packed layer A which affects the density (porosity) of the stone material to be produced. The bulk density of the raw material packed layer A to be formed is arbitrary and can be appropriately adjusted according to the required density of the stone material and the like, but usually, the bulk specific gravity / true specific gravity is in the range of 0.3 to 0.95. That is, the raw material packed layer A
Is filled to such an extent that the porosity of the inside becomes 70 to 5%.

Next, in the step (C1), carbon dioxide gas is blown into the raw material filling layer A as shown in FIG. In carrying out this step (C1), a lid 7 (a rigid lid or a sheet or the like) is mounted on the upper portion of the mold 1, and the mounting of the lid 7 causes the mold 1 to be substantially airtight. Become. The lid 7 is provided with a gas exhaust pipe 8 (gas exhaust part). In addition, there is a space above the raw material filling layer A in the mold 1, and this space forms a gas exhaust side pressure equalizing chamber 9 adjacent to the raw material filling layer A. In the case where a sheet or the like is used for the lid 7, a gap or the like between the mold 3 and the sheet may be used as the gas exhaust unit.

The carbon dioxide gas blown into the raw material filling layer A is preferably humidified in order to prevent the raw material filling layer A from drying. Therefore, when supplying carbon dioxide to the raw material packed layer A, it is preferable that carbon dioxide gas is once blown into water to saturate H ₂ O, and then supplied to the raw material packed bed A. Drying can be prevented to promote the carbonation reaction.

In the embodiment shown in FIG. 1, carbon dioxide gas is supplied into the pressure equalizing chamber 4 on the gas supply side by the gas supply pipe 5, and the carbon dioxide gas has a substantially uniform gas permeability throughout the partition wall 3 (gas passage hole). Is introduced into the raw material packed bed A through the raw material packed bed A, and then rises from the upper surface of the raw material packed bed.
After that, the gas is exhausted out of the system by the gas exhaust pipe 8. By performing such a supply of carbon dioxide gas for a certain period (for example, several hours to several hundred hours), uncarbonated Ca in the raw material in the raw material packed bed A and carbon dioxide gas react via water (uncarbonated carbon). (Carbonation reaction of Ca), and the raw material is solidified using the calcium carbonate generated as a main binder to obtain a solidified carbonic acid product.

In the embodiment of FIG. 1 (the same applies to the embodiments of FIGS. 2 and 3), carbon dioxide gas is supplied into the raw material filling layer A from substantially the entire bottom surface of the mold 1, and Since the exhaust gas is exhausted from substantially the entire upper surface, the flow of carbon dioxide gas in the raw material packed bed A is extremely uniform, and the direction of the gas flow is also uniform. Variations in the amount of carbonation reaction are particularly small, and a large number of continuous pores are likely to be formed in the gas ventilation direction.

According to the second aspect of the present invention, when forming the raw material-filled layer with the raw material to which water is added, the raw material in the mold is vibrated, and the water content of the raw material is adjusted after the formation of the raw material-filled layer. Thereby, the filling property of the raw material filling layer is made uniform, and the passage of the carbon dioxide gas is formed uniformly throughout the raw material filling layer. FIG. 2 (a drawing showing the mold in a longitudinal section) shows one embodiment of the second invention of the present application, in which a mold 1, a vibration device 2, and a raw material filling formed in the mold 1 are filled. Since the configuration of the layer A and the like are the same as those shown in FIG. 1, the same reference numerals are given and the detailed description is omitted.

In the second invention of this application, the step (A2) of adding water to the raw material a and mixing the raw material a with the raw material a
Is charged into the mold 1 to form the raw material packed layer A, and then a step (B2) of removing excess moisture in the raw material packed layer A, and a step of blowing carbon dioxide gas into the raw material packed layer A (C2 ). First, in the step (A2), water is added to and mixed with the raw material a. However, in the present invention, since the water content is adjusted after the formation of the raw material packed layer, an excessive amount of the raw material a is used in the step (A2). Water, that is, water in such an amount that the volume ratio [f / w] of the raw material f to the water w is less than 4 may be added.

Next, in the step (B2), as shown in FIG. 2 (a), the raw material a to which water has been added in the step (A2) is charged into the mold 1, and during the charging and / or Alternatively, the material filling layer A is formed by giving vibration to the material a in the mold 1 after charging. The method of forming the material-filled layer A is the same as in the above-described embodiment of FIG. further,
In this step (B2), as shown in FIG. 2 (b), the water content in the raw material packed layer A is adjusted. In this moisture adjustment, excess moisture in the raw material packed layer A is evaporated and removed so that the volume ratio [f / w] between the raw material f and the water w is 4 to 6. By vibrating the raw material in the mold when forming the raw material packed layer and adjusting the water content in the raw material packed layer to a specific range after the formation of the raw material packed layer, the filling property of the raw material packed layer is improved. And the passage of carbon dioxide gas is formed uniformly throughout the raw material packed bed.

In order to evaporate excess water in the raw material packed layer A, a method of indirectly heating the raw material packed layer A,
An appropriate method such as a method of drying under reduced pressure or vacuum may be employed. For example, in the case of the latter method, a decompression pump or a vacuum pump is provided in an exhaust system connected to the gas exhaust pipe 8, and as shown in FIG. The inside of the mold 1 is decompressed or evacuated to partially evaporate the moisture in the raw material packed layer A, and this is exhausted through the gas exhaust pipe 8. In the case of the former method, for example, the mold 1 is put into a heating chamber (for example, a processing chamber heated by combustion exhaust gas or the like) and heated, or the mold 1 is formed into a double The raw material packed bed is heated by flowing a high-temperature gas (combustion exhaust gas or the like) into the inside of the heavy structure, and a part of the water in the raw material packed layer A is evaporated. Next, in the step (C2), carbon dioxide gas is blown into the raw material packed layer A as shown in FIG. This step (C2) is the same as the above-described embodiment of FIG.

According to the third aspect of the present invention, when forming a raw material-filled layer from a raw material to which water is added, uncarbonated Ca and an inert gas are passed through the raw material layer to secure a gas passage. By imparting vibration to the raw material, the filling property of the raw material packed layer is made uniform so that the carbon dioxide gas passage is formed uniformly throughout the raw material packed layer.

FIG. 3 (drawing showing the mold in a longitudinal section)
Shows an embodiment of the third invention of this application, and the configurations of a mold 1, a vibration device 2, a raw material filling layer A formed in the mold 1, and the like are the same as those shown in FIG. Because there is
The same reference numerals are given and detailed description is omitted. In the third invention of this application, a step (A3) of adding and mixing water to the raw material a.
A step (B3) of charging the water-added raw material a into the mold 1 to form a raw material-filled layer A;
(C3).

First, in the above step (A3), water is added to the raw materials and mixed. In the present invention, when forming the raw material packed layer, a gas (an inert gas with respect to uncarbonated Ca) is contained in the raw material layer. ) Is vibrated while aeration is carried out, so that the carbon dioxide gas path is formed uniformly in the raw material packed bed. In this step (A3), a certain amount of water May be added. For this reason, the amount of water added is not particularly limited, but the volume ratio [f / w] of the raw material f and the water w.
It is preferable to add water so that the value of pH becomes 3.5 to 6. If the volume ratio [f / w] between the raw material f and the water w is less than 3.5, water is excessive, so that when forming the raw material packed layer, a gas (a gas that is inert to uncarbonated Ca) is discharged. Even if it is ventilated, there is a possibility that the carbon dioxide gas passage cannot be formed uniformly in the raw material packed layer. On the other hand, the volume ratio [f /
w] exceeds 6, the water content in the raw material packed bed is too small,
The carbonation reaction via water does not occur sufficiently.

Next, in the step (B3), FIG.
As shown in the figure, the raw material a added with water in the step (A3)
Is charged into the mold 1 and the raw material is charged by vibrating uncarbonated Ca and inert gas into the raw material layer in the mold 1 during and / or after the charging. The layer A is formed. Here, as the uncarbonated Ca and the inert gas, any kind of gas can be used as long as the amount of carbon dioxide gas is equal to or less than air, such as air, nitrogen gas, and argon gas.

In the embodiment shown in FIG. 3, after the raw material a to which water is added is charged into the mold 1, the raw material layer is vibrated while the raw material a is passed through the gas supply side pressure equalizing chamber 4 from the gas supply pipe 5. Air is blown into the layer. In this way, by passing uncarbonated Ca and an inert gas through the raw material layer and applying vibration while securing a gas passage, the filling property of the raw material packed layer A is made uniform, and carbon dioxide gas is supplied to the entire raw material packed layer. Are formed uniformly.

The gas (inert with respect to uncarbonated Ca) is introduced into the raw material layer and the vibration is imparted during the charging of the raw material a into the mold 1 or during the charging. It may be performed both after entering. Also in this embodiment, vibration is given while the raw material layer is pressed from above by the pressing plate 6 which is a pressing means, but the pressing plate 6 has gas through holes 6 for letting the gas escape.
0 is formed. Next, in the step (C3), FIG.
As shown in (b), carbon dioxide gas is blown into the raw material packed layer A.
This step (C3) is the same as the above-described embodiment of FIG.

In each of the embodiments described above, after the raw material filling layer A is solidified by carbonation, the raw material filling layer A is released from the mold by dismantling the mold, and the carbonized solid is taken out. The shape (internal shape) of the mold used in the production method of the present invention is arbitrary, and for example, the cross-sectional shape is circular, elliptical, triangular, polygonal or larger than quadrangle, star, or the like, or the whole shape is spherical. , An elliptical shape, a polyhedral shape of tetrahedron or more, a conical shape, a columnar shape, a tetrapot shape, and the like.

Hereinafter, preferable conditions of the uncarbonated Ca-containing raw material, carbon dioxide, and the like used in the production method of the present invention will be described. The uncarbonated Ca-containing raw material used in the production method of the present invention has a composition of CaO and / or Ca (OH) ₂
As long as it contains C, and therefore C as a mineral
aO, Ca _{(OH) 2} other, 2CaO · _SiO 2, 3
Those that are present in solid particles as part of the composition, such as CaO.SiO ₂ and glass, are also included.

Although there is no particular limitation on the kind of such uncarbonated Ca-containing raw material, in particular, CaO (and / or Ca (O
H) Slag and concrete (for example, waste concrete) generated in the steel manufacturing process are preferable in that the content of ₂ ) is high and resources can be recycled. In addition to the above-mentioned slag and concrete, mortar, glass, alumina cement, CaO-containing refractories, and the like can be mentioned. One or more of these aggregates of solid particles may be used alone or in combination, or slag and / or concrete may be used. Can also be used as a mixture. These materials are crushed if necessary, and used as an aggregate of powdery and / or granular solid particles.

The slag generated in the steel making process includes blast furnace slag such as blast furnace slow cooling slag and blast furnace granulated slag, decarburized slag, dephosphorized slag generated in processes such as pretreatment, converter and casting, and desulfurization. Examples include slag, desiliconized slag, steelmaking slag such as cast slag, ore reduction slag, electric furnace slag, and the like, but are not limited thereto, and a mixture of two or more slags is used. You can also. Further, as the concrete, for example, waste concrete generated by demolishing a building or civil engineering structure or the like can be used.

The uncarbonated Ca-containing raw material is metallic iron,
It can include one or more of iron oxide, soluble silica, and the like. When the solidified carbonate produced by the method of the present invention is used as a material for submersion in water and the like, it effectively acts as a fixing agent for sulfur and phosphorus in water and a nutrient source for aquatic plants such as algae. In addition to these, an arbitrary component (particle) can be contained in an appropriate amount, that is, as long as the strength of the solidified carbonate is not reduced. In addition, as a component to be a binder, for example, a small amount of cement, granulated slag, or the like may be added. The particle size of the uncarbonated Ca-containing raw material is not particularly limited, but generally the total amount is 50 mm or less,
Preferably, it is substantially 6 mm or less.

As the carbon dioxide gas (or carbon dioxide-containing gas) to be used, for example, lime burning factory exhaust gas (usually CO ₂ : about 25%) and heating furnace exhaust gas (usually CO ₂ : (Approximately 6.5%) and the like, but are not limited thereto. Further, if the CO ₂ concentration in the carbon dioxide-containing gas is too low, there is a problem that the treatment efficiency is reduced, but other problems are not particularly significant.
Thus, although the CO ₂ concentration is not particularly limited, it is preferable that the CO ₂ concentration of 3% or more to do efficient processing.

Also, there is no special restriction on the amount of carbon dioxide blown.
Gas is blown to the extent that the packed bed does not flow.
As a general guide, 0.004 to 0.5
m³/ Min · t (raw material ton)
It is sufficient if it can be secured. The gas injection time (carbonation
There is no special restriction on the processing time, but as a guide,
Gas (CO₂) Is 3% or more of the weight of the raw material
At the time, that is, when converted to gas amount, 1 t
5m³Above, preferably 200m³CO above ₂Is supplied
It is preferable to perform gas blowing until it is performed.

Although the carbon dioxide gas to be blown may be at room temperature, it is advantageous if the temperature of the gas is higher than room temperature, because the reactivity increases accordingly. However, if the gas temperature is excessively high, the moisture in the raw material packed bed is dried, or CaCO ₃ becomes CaO _3.
Because the will decompose into CO _2, it is necessary to use the temperature of the gas to the extent that even does not cause such degradation when using a hot gas. The solidified porous carbonated product produced by the present invention includes stones for construction of fishing reefs / algae reefs, stones for rocky shores, stones for water purification, stones for water-permeable pavement, blocks for water-permeable pavement, blocks for buried drains, blocks for hydroponics. It can be used for various uses including a cultivation base material, a water purification filter, and a water supply container.

[0042]

EXAMPLE Steelmaking slag mixed with water (-2 m)
m) was placed in a cylindrical mold having an inner diameter of 100 mm, and was placed on a vibrating table to apply vibration.
mm. Further, in some of the examples of the present invention, air was ventilated from the bottom of the mold while applying vibration to the raw material layer. A carbon dioxide-containing gas (carbon dioxide concentration: 25%) from the bottom of the mold into the raw material packed layer thus formed
Was blown at a supply rate of 1 L / min for 40 hours to carry out a carbonation treatment. Table 1 shows the filling conditions of the raw material in the mold, the ventilation state when blowing carbon dioxide gas, the solidification state after carbonation, and the like.

The state of ventilation when blowing carbon dioxide gas was evaluated as follows. ：: Ventilation resistance (pressure loss) ΔP ≒ 0 ○: Ventilation resistance (pressure loss) ΔP <800 mmAq ×: No ventilation (gas inlet side pressure: 800 mmAq) In addition, the solidification state after carbonation treatment was evaluated as follows. did. ：: sufficiently solidified and blocked. X: The solidification is insufficient, and the block can be easily broken by hand.

[0044]

[Table 1]

[0045]

According to the present invention described above, in a method for producing a solid carbonated product by filling an uncarbonated Ca-containing raw material in a mold and blowing carbon dioxide gas into the raw material-filled layer, Regardless of the shape of the layer, the amount of carbonation reaction in each part of the raw material packed layer can be made uniform, and a large number of continuous open pores can be formed in the carbonized solidified body. It is possible to produce a carbonized solid of high quality.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an embodiment of the first invention of the present application in a state in which a mold is longitudinally sectioned.

FIG. 2 is an explanatory view showing an embodiment of the second invention of the present application in a state in which a mold is longitudinally sectioned.

FIG. 3 is an explanatory view showing an embodiment of the third invention of the present application in a state in which a mold is longitudinally sectioned.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Mold frame, 2 ... Vibration device, 3 ... Partition wall, 4 ... Gas supply side equalizing chamber, 5 ... Gas supply pipe, 6 ... Push plate, 7 ... Cover, 8 ... Gas exhaust pipe, 9 ... Gas exhaust side equalization Pressure chamber, 20 ... Support table, 21 ...
Coil spring, 22: eccentric rotary roller, 60: gas through hole, a: raw material, A: raw material packed layer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B09B 3/00 B09B 3/00 ZAB 4K002 C22B 1/243 304A 304J (72) Inventor Tatsuto Takahashi Chiyoda-ku, Tokyo 1-2-1 Marunouchi Nihon Kokan Co., Ltd. (72) Inventor Katsuhiro Nishi 2-15-1, Konan, Minato-ku, Tokyo Kokan Mining Co., Ltd. F-term (reference) 2B003 AA01 BB01 BB03 DD04 EE04 2B022 AA05 BA05 2B314 PC03 PC26 4D004 AA16 AA43 BA01 BA02 BA10 CA14 CA34 CA45 CC01 DA02 DA03 DA08 DA09 4K001 BA12 CA30 4K002 AE06

Claims (6)

[Claims] A raw material-filled layer is formed by filling a powdery and granular uncarbonated Ca-containing raw material to which water has been added into a substantially airtight mold having a gas supply part and a gas exhaust part. Blowing a carbon dioxide gas or a carbon dioxide-containing gas into the raw material packed layer to solidify the uncarbonated Ca-containing raw material using calcium carbonate generated by a carbonation reaction of the uncarbonated Ca as a main binder to produce a carbonized solid body A step (A1) of adding and mixing water to the uncarbonated Ca-containing raw material such that the volume ratio [f / w] of the uncarbonated Ca-containing raw material f to water w is 4 to 6. The uncarbonated Ca-containing raw material to which water has been added in the step (A1) is charged into a mold, and vibration is applied to the uncarbonated Ca-containing raw material in the mold during and / or after the charging. (B1) forming a raw material packed layer by applying (C1) blowing a carbon dioxide gas or a carbon dioxide-containing gas into the raw material packed layer formed in the step (B1). 2. A raw material-filled layer is formed by filling a powdery granular uncarbonated Ca-containing raw material to which water has been added into a substantially airtight mold having a gas supply part and a gas exhaust part. Blowing a carbon dioxide gas or a carbon dioxide-containing gas into the raw material packed layer to solidify the uncarbonated Ca-containing raw material using calcium carbonate generated by a carbonation reaction of the uncarbonated Ca as a main binder to produce a carbonized solid body In step (A), water is added to the uncarbonated Ca-containing raw material and mixed.
2) and charging the uncarbonated Ca-containing raw material to which water has been added in the step (A2) into the mold, and during and / or after the charging, the uncarbonated Ca-containing raw material in the mold. The raw material-filled layer is formed by applying vibrations to the raw material-filled layer. Characterized by comprising a step (B2) of evaporating and removing excess water from the inside, and a step (C2) of blowing a carbon dioxide gas or a carbon dioxide-containing gas into the raw material packed layer after the step (B2). Manufacturing method of solidified body. 3. A raw material-filled layer is formed by filling a powdery and granular uncarbonated Ca-containing raw material to which water has been added into a substantially airtight mold having a gas supply part and a gas exhaust part. Blowing a carbon dioxide gas or a carbon dioxide-containing gas into the raw material packed layer to solidify the uncarbonated Ca-containing raw material using calcium carbonate generated by a carbonation reaction of the uncarbonated Ca as a main binder to produce a carbonized solid body In step (A), water is added to the uncarbonated Ca-containing raw material and mixed.
3) and charging the uncarbonated Ca-containing raw material to which water has been added in the step (A3) into the mold, and during and / or after the charging, the uncarbonated Ca-containing raw material in the mold. Uncarbonated Ca
(B3) forming a material-filled layer by applying vibrations while allowing an inert gas to flow, and blowing carbon dioxide gas or a gas containing carbon dioxide into the material-filled layer formed in the step (B3) ( And C3). 4. In the step (A3), water is added to the uncarbonated Ca-containing raw material such that the volume ratio [f / w] of the uncarbonated Ca-containing raw material f to water w becomes 3.5 to 6. The method for producing a solidified carbonic acid product according to claim 3, wherein the mixture is added and mixed. 5. The method according to claim 1, wherein in step (C1), (C2) or (C3), humidified carbon dioxide or a carbon dioxide-containing gas is blown into the raw material packed bed. A method for producing a solidified carbonate according to the above. 6. In the step (B1), (B2) or (B3), the uncarbonated Ca-containing material layer charged in the mold is vibrated while being pressurized from above by a pressurizing means. 3. The method according to claim 1, wherein a filling layer is formed.
6. The method for producing a solidified carbonate according to 3, 4, or 5.