JPH1169924A - Method of creating or improving seaweed beds - Google Patents

Abstract

(57) [Summary] [Problem] To provide a seaweed bed creation method that allows a wide range of seaweed bed creation sites to be selected, and that can create a seaweed bed in a short period of time with a small amount of labor and cost, and also enables large-scale creation. . The present invention relates to a method of creating a seaweed bed that focuses on the growth or proliferative action of seaweed in an existing seaweed bed, and uses the existing seaweed bed itself to set and grow seaweed seeds and seedlings on an artificial base, The feature is that a heavy material is temporarily placed and settled on an existing seaweed bed, seaweeds are grown and grown on the surface of this material, and then the material is collected to create a seaweed bed or seaweed beds. The seed material is relocated to a place where the seeds are to be propagated, and another material on which seaweeds are to be grown is arranged around the seed material, and the seaweed of the seed material is propagated to the other materials.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for constructing or improving a seaweed bed. In the present invention, the “alga beds” refer to a community of algae and seaweeds (hereinafter, collectively referred to as “seaweeds”) that grow on the sea floor.

[0002]

BACKGROUND OF THE INVENTION Seagrass beds are places for the production of marine animals and plants in coastal waters, and are indispensable places for habitats of useful seafood and seaweeds, spawning grounds for seafood, breeding grounds for larvae, and feeding grounds. It can be said that there is. Recently, nitrogen and phosphorus in seawater have been removed by being taken up by seaweeds or by other organisms through the food chain in the seaweed beds, and suspended substances settled in the seaweed beds and removed from the water. Attention has also been focused on the water purification effect of seaweed beds.

However, in recent years, seaweed beds have been rapidly disappearing and declining due to the effects of coastal land reclamation and seawater pollution. In recent years, especially in many coastal waters, a phenomenon called “iso-yake” has occurred. And it is a big problem. Therefore, it is required to quickly establish a seaweed bed creation method for restoring the seaweed bed. Conventional methods for creating a seaweed bed can be roughly divided into the following two methods.

(1) A base (mainly a stone material such as a natural stone or a concrete block) for growing seaweeds is installed in a place where a seaweed bed is to be formed, and seeds and mother algae of the seaweeds are transplanted to the base. And conduct management for seaweed cultivation as necessary. (2) Places where seaweed beds are likely to occur in the environment, that is, places that are suitable for the creation of seaweed beds in terms of water depth, water quality, and ocean currents, and that are within the reach of seaweed spores and the like from existing seaweed beds. Is selected and a base is set up on it to be maintenance-free (ie, transplantation of seeds and seedlings and their management are not basically performed)
To create a seaweed bed.

[0005]

However, among these methods, although the method (1) has an advantage that a selection range of a seaweed bed creation site is wide, basically, the creation of the seaweed bed is entirely artificial. Depending on the environment of the seaweed bed development site, it is necessary to sufficiently control the rooting and growth of the transplanted seeds and seedlings, which requires a great deal of labor and cost. Not at all suitable.

On the other hand, the method (2) is a maintenance-free method of creating a seaweed bed except for installing a base.
The method has the advantage of requiring much less labor and cost than the method (1), but lacks versatility because the place where a seaweed bed can be created is limited. According to one report, in order to create a seaweed bed in a place where natural seaweed beds do not occur within the appropriate period by the method (2), the range of spores and seeds of seaweed from existing seaweed beds must be improved. Considering this, it is preferable to select a place that is within 100 m of the existing seaweed bed. Therefore, it is considered that it is difficult for this method to create a seaweed bed in a place where the seaweed beds in the entire surrounding sea area have disappeared due to so-called scorching.

Accordingly, an object of the present invention is to create a seaweed bed in which the selection range of the seaweed bed can be widened, the seaweed bed can be created in a short time with a small amount of labor and cost, and a large-scale seaweed bed can be created. Or to provide an improved method.

[0008]

Means for Solving the Problems In the course of examining a new seaweed bed creation method that can solve the above-mentioned problems, the present inventors have focused on the proliferative power or the proliferating action of seaweed on existing seaweed beds. The use of the existing seaweed bed itself for the establishment and growth of seaweed seeds and seedlings on the base, that is, by temporarily placing the base material for seaweed bed creation in the existing seaweed bed, Seeds and seedlings naturally settle and grow on the material surface,
I got the idea to use this material as a foundation for seaweed bed development. And as a result of repeated experiments and examinations based on such ideas, when materials such as stones are placed in existing seaweed beds, seaweeds settle and grow on the surface in a relatively short time, By relocating the material where this seaweed grew to the seaweed bed development site as seed material, and by distributing new material (material without seaweed growth) around it,
In a relatively short time, seed algae grow on surrounding materials,
It was found that a seaweed community unit that forms a seaweed bed could be formed.

[0009] Further, as a result of an examination of a suitable material and properties of the material on which the seaweed bed including the above-mentioned seed material is formed, it is found that the material is capable of staying on the seabed without being washed away by an ocean current or the like. Basically, the material and properties are not limited as long as it is heavy, but those having surface properties to which spores or seeds of seaweeds are easily attached as much as possible, that is, those having surface irregularities or protrusions are preferable, In particular, it has been found that an artificial stone material obtained by agglomerating slag generated in a steel manufacturing process by a specific method is extremely suitable as a material, and exhibits an excellent effect on the growth of seaweeds and the like.

The present invention has been made based on such findings, and the features thereof are as follows. [1] Temporary placement of heavy materials in existing seaweed beds,
After the seaweeds are settled and grown on the surface of the material, the material is collected and transferred to a place where a seaweed bed is to be formed or seaweeds are to be grown. A method for constructing or improving a seaweed bed, comprising disposing another material on which seaweeds are to grow on, and growing the seaweed as the seed material on the other material.

[2] In the method of the above-mentioned [1], the material is a stone material mainly made of slag generated in a steel manufacturing process, and the slag is one of powdery slag, coarse slag, and small slag. A method for constructing or improving a seaweed bed, comprising using an aggregated artificial stone material comprising a slag solidified as a binder using CaCO ₃ generated by a carbonation reaction of the slag.

[3] In the method according to the above [1], the material is a stone mainly made of slag generated in a steel manufacturing process, and the slag is one of powdery slag, coarse slag, and small slag. CaCO ₃ and MgCO ₃ produced by the carbonation reaction of the slag
₃ (provided that MgCO ₃ is present as a hydrate, a hydroxide salt or a double salt) as a binder, and use agglomerated artificial stones to create or improve a seaweed bed. Method.

[4] The method according to the above [1], wherein the material is slag produced in a steelmaking process and a powdery and / or coarse-grained additive as a main material, and the slag is powdered. Artificial stone made of at least one of granular slag, coarse-grained slag, and small slag, wherein CaCO ₃ formed by a carbonation reaction of a mixture of the slag and the additive is used as a binder to form a mass, A method for constructing or improving a seaweed bed, characterized by using:

[5] The method according to the above [1], wherein the material is slag produced in a steelmaking process and a powdery and / or coarse-grained additive as a main material, and the slag is powdered. CaCO ₃ and MgCO ₃ (where MgCO ₃ is a hydrate) composed of one or more of granular slag, coarse-grained slag, and small-lumped slag, wherein a mixture of the slag and the additive is formed by a carbonation reaction. Algae beds, including agglomerates, including a hydroxide salt or a double salt), and using a mass of artificial stone material.

[6] The method according to the above [4] or [5], wherein at least a part of the additive as a raw material of the artificial stone is made of metallic iron,
A method for constructing or improving a seaweed bed, comprising at least one selected from a metal-containing iron material, iron oxide, and iron oxide-containing material. [7] The method according to any one of the above [2] to [5], wherein the slag as a raw material of the artificial stone material is a powdery and / or coarse-grained slag that has undergone a metal removal treatment. Method of construction or improvement.

[8] In the method of the above-mentioned [4] or [5], the slag as a raw material of the artificial stone is made of powdery and / or coarse-grained slag that has undergone a metal removal treatment, and at least a part of the additive material. Is made of iron oxide and / or an iron oxide-containing material. [9] In the method according to the above [4] or [5], the slag as a raw material of the artificial stone is made of powdery and / or coarse-grained slag that has undergone ingot removal treatment, and at least a part of the additive material is metallic iron. And / or a method for constructing or improving a seaweed bed, comprising a metal-containing iron material.

[10] The method according to the above [6], [8] or [9], wherein the metal-containing iron material and / or the iron oxide-containing material which is the raw material of the artificial stone material is made of iron-containing dust and / or mill scale. Method of creating or improving seaweed beds. [11] The method according to any one of [4] to [10], wherein at least a part of the additive as a raw material of the artificial stone material is made of soluble silica and / or a soluble silica material. Creation or improvement method. [12] The method for creating or improving a seaweed bed according to the method of the above-mentioned [11], wherein the soluble silica material as a raw material of the artificial stone material comprises fly ash and / or clinker ash.

[13] In the method according to any one of the above [4] to [12], at least a part of the additive as a raw material of the artificial stone is made of CaO, Ca (OH) ₂ , MgO, Mg (OH) ₂ . A method for constructing or improving a seaweed bed comprising at least one selected from the group consisting of: [14] The method for creating or improving a seaweed bed according to any one of the above-mentioned [2] to [13], wherein at least a part of the slag which is a raw material of the artificial stone is made of granulated blast furnace slag. [15] The method for creating or improving a seaweed bed according to any one of the above-mentioned [2] to [14], wherein the porosity of the artificial stone material is 10 to 70%.

Such a method of the present invention can be used not only to construct a seaweed bed in a place where a seaweed bed does not naturally occur or where the seaweed bed has disappeared, but also to improve a place where the seaweed bed is declining (seaweed bed cultivation). ) Can also be applied.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION The details of the seaweed bed creation method (or improvement method) according to the present invention will be described below. In the present invention, first, a material to be used as a seed material is temporarily placed in an existing seaweed bed (particularly preferably, a natural seaweed bed). Existing seagrass beds, especially natural seagrass beds, have an environment where seaweeds are easier to breed than places where seaweed beds do not naturally occur (environments such as light, water quality, and currents that govern the growth of seaweeds). In addition, the seaweed beds are also places where spores (zoospores) and seeds released from seaweeds are present at the highest density. Therefore, existing seagrass beds are the most suitable place to naturally set and grow seaweed on the surface of the material.

The material deposited on the seaweed bed as described above may be of any weight and material as long as it is a heavy material that can stay on the seabed without being washed away by the ocean current or the like. As a material, for example, a natural material, an artificial stone (including a massive slag, a concrete block, or the like), a metal material (for example, a steel material or a casting), a plastic material, or a composite material thereof, such as a heavy material having a specific gravity of more than 1 Any material can be used. In addition, there is no special restriction on the form, lump, long,
Appropriate forms can be used, such as a block, a plate, a plurality of lumps, and the like placed in a basket, a net, or the like to form one material.

It is preferable that the material has irregularities or protrusions on the surface because spores and seeds of seaweeds can be easily attached and the roots of the larva are good. When the material is a stone or the like, the uneven surface is most preferably constituted by a crushed surface when the material is crushed. Since the crushed surface of the stone or the like is formed with countless large and small irregularities, the growth of spores and seeds of seaweeds and the growth of the juvenile are good. Particularly preferred artificial stone materials will be described later in detail. For materials other than those made into a single material by putting a lump or the like in a basket or net, etc., when temporarily placing the material in a seaweed bed and setting it down, pull it up to facilitate later collection. It is preferable to wrap it in a net or attach means for pulling it up (such as a wire rope).

When the material is temporarily placed and settled in the seaweed bed, it is preferable to select a time when the seaweed in the seaweed bed actively releases spores and seeds. On the surface of the material temporarily settled in the seaweed bed, seaweeds usually settle and grow in about several months to one year, and in the case of fast-growing ones, grow to an adult or a state close to an adult that produces spores and seeds . As mentioned earlier, existing seagrass beds (especially natural seagrass beds) have the highest growth potential of seaweeds on material surfaces in terms of environmental and dense seaweed spores and seeds. It is a place, so that seaweed that has grown on the material surface in a relatively short period of time can be rooted.

When the seaweed has settled and grown on the surface of the material, the material is pulled up from the seaweed bed and collected.
This material is transported to a seagrass bed creation site (or seagrass bed improvement site) while utilizing the seaweed grown on the surface to be re-sedimented as seed material, and a new material (that is, seaweed) is surrounded around the seed material. Other materials to settle on)
To sink. At this time, for example, seed materials are placed in a form of placing one to two seed materials in a range of about 10 m × 10 m and arranging new materials in a relatively dense state around the seed materials. In addition, a base may be constructed by stacking new materials, and seed materials may be placed in the base or incorporated into the base. In the present invention, a form in which new materials are laid down around seed materials may be used. Such cases are also included.

Generally, a seaweed bed is formed on a seabed with a water depth of less than 20 m. In the above-mentioned work, for example, new materials on which seaweeds carried by a carrier ship are not settled are sunk on the seabed. Then, the seed material can be suspended in the base. The material, properties, and form of the newly deposited material are the same as the material to be used as the seed material described above. Further, different materials, properties and forms may be used as the newly deposited material and the material to be used as the seed material.

According to such a method for creating a seaweed bed, spores and seeds released from the seaweed as a seed material adhere to the surrounding material, and usually, the surrounding material is removed in a relatively short period of about one year. Also, seaweeds can set and grow on the seaweeds, forming a community unit of seaweeds that make up the seaweed beds. Therefore, by laying the material on which the seaweeds are to grow on the entire area where the seaweed bed is desired to be formed, and by laying the seed materials in a state in which the seaweeds are scattered, even in a large-scale seaweed bed, The development can be done easily and quickly.

The method of the present invention can be said to be a seaweed bed creation method having both the advantages of the above-mentioned conventional methods (1) and (2) and further advantages.
In other words, the method of the present invention is to grow and grow seaweeds on the material to be used as seed material for seaweed bed creation by utilizing the growth of seaweed in existing seaweed beds. As with the conventional method of transplanting the seaweed (the conventional method of (1) described above), the seaweed can be firmly rooted in the material, and therefore, the maintenance-free seagrass bed creation method (described earlier)
Compared to the conventional method (2)), seaweeds can be propagated in a relatively short period of time and more reliably, and seaweed beds can be created. In addition, there is a great advantage that the selection range of the seaweed bed creation sites is wide. .

In addition, since the method of the present invention is to grow and grow seaweed on the material in the seaweed bed, which is the most suitable place for germination and growth of environmental Shanghai algae, the seaweed grown on the surface of the material grows. The algae are more likely to survive and grow than conventional methods in which seaweed seeds and seedlings are transplanted to materials at seaweed beds. There is a great advantage that little post-transplant breeding management is required.

On the other hand, the present invention differs from the conventional maintenance-free seaweed bed creation method in that materials to be used as seed materials are temporarily placed in an existing seaweed bed for a certain period of time, and then collected and collected. The only difference is that they need to be relocated to a location, and there is almost no need for other artificial work or seaweed cultivation management. Therefore, it can be said that the method of the present invention has simplicity and low cost close to the maintenance-free seaweed bed creation method.

Next, materials suitable as materials used in the method of the present invention will be described. Materials used in the present invention method (materials for seed materials and seaweed bed creation base) are stone materials mainly made of slag generated in the steel manufacturing process,
Slag is a particulate slag, coarse-grained slag, from one or more of the small massive slag, this slag CaCO ₃ or CaCO ₃ and MgCO ₃ which is produced by the carbonation reaction was consolidated as a binder were agglomerated Artificial stone is preferred.

Conventionally, as part of the effective use of slag (eg, blast furnace slag, converter slag, etc.) generated in a steelmaking process, attempts have been made to use slag as a material for submersion in seawater such as stones for seaweed beds and fish reefs. It has been done. The main forms of using slag as these materials are:
A method of using the massive slag as it is as a stone material for seaweed beds and a method of using the slag as an aggregate of a concrete product can be considered.

However, in the former method, the Ca contained in the slag may be dissolved in the sea and raise the pH of the surrounding seawater, and the Ca dissolved in the sea may be increased. In some cases, Mg (OH) ₂ precipitates (white sediment) due to an exchange reaction between the slag and Mg ions in the sea, and this deposits on the slag surface, and has a problem of inhibiting the formation and germination of seaweed. In addition, it can be said that the massive slag obtained from the steelmaking process is more suitable for seaweed bed stones than concrete products due to its surface properties, but it is the same as natural stone for seaweed bed stones. It has only a certain degree of function (adhesion and growth of seaweeds), and is not a stone having a special function that can promote the growth of seaweeds.

Since slag generated in the steel making process contains a large amount of metal (iron such as granular iron), slag is usually pulverized to a certain size to recover the iron contained in the slag. Recycled to the steel manufacturing process. However, slag used as a stone material for seaweed beds needs a certain size, and slag that has been pulverized for metal recovery cannot be used.
For this reason, when using massive slag as a stone material for seaweed beds, bare metal useful as a steel resource can hardly be recovered.

On the other hand, when the massive slag containing a large amount of metal as described above is submerged in the sea as it is and used as a stone material for seaweed beds, iron in the slag is oxidized depending on the sea area to be applied, and the surrounding seawater is oxidized. In some cases, it may cause a problem of causing anoxia, and furthermore, an oversupply of iron into seawater due to elution of iron. In order to avoid such problems, it is necessary to sufficiently remove the metal in the slag,
Generally, the slag component and the ingot are mixed in such a way as to be intertwined with each other, so that in order to sufficiently remove the ingot, it is necessary to finely pulverize the slag more finely than in the case of the ingot collection described above. The slag finely ground cannot be used as a material for submerging in the sea such as for seaweed beds.

On the other hand, since the latter method uses slag as an aggregate of a precast concrete body, problems such as the case where the massive slag is submerged as it is in the sea are unlikely to occur. However, since the material obtained by this method is a concrete product whose surface is made of cement mortar, the properties of massive slag (for example, uneven surface properties, etc.) that can be expected to have a certain function for seaweed beds etc. I can't even use it.

In order to solve such a problem, the present inventors have developed a CaCO which is produced by a carbonation reaction of a slag composed of at least one of a granular slag, a coarse slag and a small slag.
₃ or CaCO ₃ and MgCO ₃ solidified as a binder and agglomerated are very suitable as seaweed bed stones. It has been found that it does not cause white precipitation, and also exhibits excellent effects in growing seaweeds.

In sea areas where it is necessary to suppress the deoxygenation of seawater due to the oxidation of iron and the excessive supply of iron into seawater, powdery or coarse slag that has undergone iron ingot removal treatment is used. Produced by the carbonation reaction as described above
By coagulating CO ₃ or CaCO ₃ and MgCO ₃ as a binder and using the agglomerated material as a stone material for seaweed beds, it is possible to reduce oxygenation of seawater due to oxidation of iron and excessive supply of iron to seawater, Has found that it does not cause an increase in the pH of seawater and exhibits an excellent effect in growing seaweeds and the like.

Further, such a massive artificial stone material is made of a slag composed of at least one of a powdery granular slag, a coarse granular slag, and a small massive slag (a slag which has been subjected to the above-described metal removal treatment if necessary). The slag particles can be easily manufactured by stacking or filling to a desired density and causing a carbonation reaction in the stack or packed layer in the presence of carbon dioxide gas to consolidate the slag particles. The stone material to be used can be adjusted to an arbitrary density and size according to the conditions of the seabed and currents to be applied, and the stone can be very easily massed.

Specifically, the artificial stone has the following advantages. Since most of CaO (or Ca (OH) ₂ generated from CaO) contained in the slag changes to stable CaCO ₃ , the pH rise of seawater due to the elution of Ca and the Mg content of seawater and Mg ions in seawater The occurrence of white precipitation due to the reaction can be prevented. On the other hand, the slag contains an appropriate amount of iron (particularly metallic iron and metal-containing iron material), and this iron is eluted into seawater, so that iron is replenished as a nutrient in seawater, and this is used to grow seaweed. Works effectively.

A slag composed of at least one of a granular slag, a coarse slag, and a small slag, or a lump obtained by carbonating and solidifying a granular slag and / or a coarse slag is entirely (surface and internal) ) Has a porous property, which makes it easy for seaweed to adhere to the surface of the stone, and because the inside of the stone is porous, an ingredient effective in promoting the growth of seaweed contained in the stone ( For example, soluble silica and iron (described later) tend to elute into seawater. Therefore, the growth of seaweeds can be effectively promoted as compared with a case where massive slag is used as it is as a stone material for seaweed beds or a concrete product using slag as an aggregate.

In particular, according to the method of the present invention, the seaweeds settle and grow on the materials temporarily laid in the existing seaweed beds, and the seaweeds grow on the materials arranged around the seed materials at the seaweed bed creation site. ,
It is necessary to promote the growth effectively, and especially to promote the growth of the larvae of the seaweed on the surface of the material. In this regard, the active ingredient eluted from the seaweed bed stone into water is more effective for growing seaweed larvae, since the individual of the seaweed acts more effectively as the stone is closer to the stone. The growth of the young body can be effectively promoted, and the effect of the method of the present invention can be further enhanced.

When the massive slag itself is used as a stone material for a seaweed bed, the size of the molten slag is generally limited by the cooling method and conditions of the molten slag (usually, the maximum is 800 at maximum).
mm), and it is difficult to obtain large blocks of stone having a uniform size. On the other hand, a slag composed of at least one of powdery slag, coarse slag, and small slag, or a stone obtained by carbonating and solidifying powdery and / or coarse slag, has a shape in which carbonation is solidified. The size can be arbitrarily adjusted by selection or selection of a cut-out shape after carbonation and solidification, and a large block of stone, which is particularly preferable as a stone for seaweed beds, can be easily obtained.

It is preferable to use a seaweed bed stone having an optimum density (specific gravity) in accordance with the condition of the seabed or ocean currents. For example, when a stone having a high density is laid on the seabed where sludge is deposited, However, the stone sinks into the sludge and cannot serve as a base for the seaweed bed.
In this regard, a slag composed of at least one of powdery slag, coarse slag, and small slag, or a stone material obtained by carbonating and solidifying a granular or coarse slag is a bulk density of slag at the time of carbonating and solidifying ( The density can be arbitrarily adjusted by appropriately adjusting the pressure density.

In the case of the seaweed bed stone obtained from the powdery and / or coarse-grained slag that has undergone the ingot removal treatment, the main ingot is removed, so that the seawater is deoxygenated or iron is removed. When applied to sea areas where excessive supply of iron is a problem, problems such as oxygen depletion of seawater due to oxidation of metal and excessive supply of iron due to elution of metal into seawater do not occur. In addition, the seaweed bed stone obtained from the slag from which the ingot has been removed in this way, since the ingot has been removed, the component that contributes to the solidification of the slag in carbonation is relatively large,
This is advantageous in securing the strength of the stone.

The slag which is the main raw material of the artificial stone is blast furnace slag such as blast furnace slow cooling slag and blast furnace granulated slag, decarburized slag and dephosphorized slag generated in steps such as pretreatment, converter and casting. Steelmaking slag such as desulfurized slag, desiliconized slag, cast slag, ore reduction slag, electric furnace slag, etc., but are not limited thereto, and a mixture of two or more slags Can also be used. An example of a typical slag composition among these slags is shown below.

(1) Decarburized slag: T. Fe: 17.5
%, CaO: 46.2%, SiO 2: 11.7%, Al 2
O ₃ : 1.4%, MgO: 8.3%, MnO: 6.2
%, P: 0.76%, S: 0.04% (2) Dephosphorized slag ... Fe: 5.8%, CaO: 5
_{4.9%, SiO 2: 18.4%} , Al 2 O 3: 2.8
%, MgO: 2.3%, MnO: 1.9%, P: 2.8
6%, S: 0.03% (3) Desulfurized slag ... Fe: 10.5%, CaO: 5
_{0.3%, SiO 2: 10.0%} , Al 2 O 3: 5.4
%, MgO: 1.1%, MnO: 0.4%, P: 0.1
3%, S: 1.8%

(4) Desiliconized slag: Fe: 10.5
%, CaO: 13.6%, SiO ₂ : 43.7%, Al ₂
O ₃ : 3.8%, MgO: 0.4%, MnO: 15.8
%, P: 0.10%, S: 0.19% (5) Granulated blast furnace slag: FeO: 0.3%, CaO: 4
2.0%, SiO ₂ : 33.8%, MnO: 0.3%,
_{MgO: 6.7%, Al 2 O} 3 ... 14.4% Of the slag generated in the iron and steel manufacturing process, the dephosphorization slag due to the high P content, also desiliconization slag Mn
Due to the high content of O, it is difficult to use each as a raw material for cement, but these slags can be used as a main raw material for artificial stone without any problem.

The slag generated in the steel manufacturing process as described above contains a relatively large amount (usually, about several to 30% by weight) of base metal (iron such as granular iron), although the degree of slag varies. Generally, in order to recycle such iron to the steel making process, slag is recovered in slag. Usually, slag is pulverized in order to perform this metal recovery, and therefore, slag that has undergone the metal recovery process, including slag that has originally been pulverized, coarsened, or agglomerated, is inevitably powdered and granulated. , Coarse or small lumps. Usually, the particle size of the slag particles that have undergone this slag recovery step is on the order of cm or less (for example, 5 cm or less).

Here, the bullion collecting process is a process of collecting bullion from slag for the purpose of recycling the bullion contained in the slag as described above. This is different from the processing performed for the purpose of substantially removing the metal in the slag. Therefore, in the slag recovery processing, the slag is generally not pulverized as finely as the slag removal processing, and a considerable amount of the slag still remains in the slag after the processing. On the other hand, the slag removal process described below refers to a process in which slag is finely pulverized into powder and / or coarse particles, and all the slag is removed from the slag except for the inevitable remaining slag. Say.

The artificial stone material for the seaweed bed is made from at least one of the above-mentioned powdery and granular slag, coarse-grained slag, and small slag. However, the slag may be at least one of powdery and granular slag, coarse-grained slag, and small-lumped slag, and does not have to go through the above-described slag collecting step.

In the case where these slags are used as a material for seaweed beds, generally, the iron content in the slag may not be as low as when the slag that has undergone the ingot removal treatment is used as a stone material. Rather, it is better to contain an appropriate amount of iron (particularly, metallic iron such as granular iron or a metal-containing iron material). This is because iron (metallic iron, metallic iron-containing material, etc.) contained in the slag in an appropriate amount elutes into seawater, so that iron is replenished as a nutrient in seawater, and this effectively acts on the growth of seaweed. is there. For this reason, it is usually appropriate that the iron content in the slag is 3% by weight or more.

The iron in the slag may be left without recovering part or all of the metal (granular iron or the like) originally contained in the slag, and may be used as it is or as described later. As in the case of using slag that has undergone the slag removal process as a stone material, substantially all of the slag in the slag is temporarily removed (except for the inevitable slag) by the slag removal process. After that, it may be ensured by adding metallic iron and / or a metal-containing iron material as an additive.

In the case of the latter method, that is, a method in which substantially all of the metal in the slag is once removed by the metal removal treatment, and then metal iron and / or a metal-containing iron material is added as an additive, There are the following advantages. (1) It is difficult to accurately adjust the amount of the slag remaining in the slag by a method in which a portion of the slag originally contained in the slag (granular iron or the like) is left without being collected. That is, the collection of bullion from the slag is performed by magnetic separation, etc., due to the nature of this magnetic separation processing, it is quite difficult to recover the bullion so that a certain amount of bullion remains, Even when this is possible, it is necessary to perform complicated controls and operations in performing magnetic separation. On the other hand, the latter method removes and collects substantially all of the metal originally contained in the slag, and re-adds metallic iron such as granular iron or a metal-containing iron material. Iron content can be arbitrarily controlled.

(2) For the same reason as described above, the former method, that is, the iron content (granular iron etc.) originally contained in the slag
In the method of leaving a part of the slag without collecting it, the shape and size of the slag remaining in the slag cannot be selected. As will be described later, in general, so-called granular iron, which is metallic iron, is preferable as the iron component contained in the slag that should constitute the stone material for the seaweed bed, but when a part of the metal is removed and recovered from the slag by magnetic separation or the like. However, such grain iron does not always remain,
Rather, the granular iron may be recovered and removed, leaving a large-sized ingot. On the other hand, in the latter method, the shape and size of the metallic iron or the like to be added to the slag can be arbitrarily selected, and a preferable iron source such as granular iron can be contained in the slag.

Therefore, in order to obtain slag containing metallic iron or metallic iron-containing material, it is necessary to first remove substantially all of the metal in the slag (except for the metal which cannot be removed inevitably) by the metal removal treatment. It is most preferable to add metal iron or a metal-containing iron material again. As will be described later, generally, the slag removal processing is performed after pulverizing the slag into powder or coarse particles,
The slag which has been subjected to the metal removal treatment, including the slag which has been subjected to magnetic separation or the like and is originally in a state of granulated or coarse-grained particles, is inevitably in the form of powder and / or coarse particles (usually in the order of mm). Or smaller slag particle size)
It is.

In the above-described metal removal treatment, it is preferable that the metal in the slag is removed as much as possible except for the metal components inevitably remaining. Usually, the iron content in the slag after the metal removal treatment is reduced. The (metal) content is preferably less than 3% by weight. Then, an appropriate amount of metallic iron such as granular iron and / or a metal-containing iron material is added to the slag that has undergone such ingot removal treatment, and a slag having a desired iron content including the metal iron and the metal-containing iron material is obtained. can get.

The metallic iron or metal-containing iron material to be added to the slag is such that a large-sized metal iron or metal-containing iron material does not hinder the molding when the slag is formed, From the viewpoint of increasing the specific surface area of iron and the like, and increasing the elution of iron from the stone laid in the sea, particles having a small particle size and a uniform size are preferable. Iron is best.
In addition, as the granular iron, not only the granular iron recovered from the slag but also any other granular iron that can be procured can be used.

Further, in the case where the stones are laid, for example, in the sea area or the like, the oxidation of the metal contained in the slag causes oxygen depletion of the seawater or excessive supply of iron to the seawater. After the slag to be used is subjected to the metal removal treatment, the slag is used as a raw material of the stone material without adding the metal iron or the metal-containing iron material as described above.

As described above, the slag generated in the steelmaking process contains a relatively large amount of slag, though varying in degree, and the slag in such slag is also removed by the above-described slag collection process. A considerable proportion can be recovered. However, since the slag component and the ingot are generally mixed in a state of being entangled with each other, the ingot cannot be sufficiently removed by the pulverization treatment (crushed particle size) of the degree performed in the ordinary ingot collection step. Therefore, even after the slag recovery process, a considerable amount of slag still remains in the slag. For this reason, when stones obtained from slag that have just been recovered are submerged in the sea, depending on the area of the sea where the slag is submerged, the oxidation of the metal in the slag may cause the seawater to become deoxygenated or the slag may enter the seawater. This causes a problem such as an excessive supply of iron due to elution of iron.
Therefore, as for the slag to be used as a raw material, a slag to be used as a raw material in which a main slag is removed by slag removal processing is used.

As described above, since the slag component and the ingot are usually mixed in the slag in a densely entangled state, in the ingot removal process, the slag is formed into a powdery or coarse particle state. Must be removed (removal by magnetic separation or the like). Therefore, slag that has undergone metal removal processing to be used as a raw material, including slag originally in a powdered or coarse-grained state, is inevitably powdered and granular. And / or coarse particles. Usually, the particle size of the slag that has undergone this metal removal treatment is on the order of mm or less (for example, 5 mm or less).
belongs to.

Therefore, the seaweed bed stones to be applied to the sea area where the deoxygenation of seawater and the excessive supply of iron are problematic are the powdery and / or coarse slag that has undergone such a metal removal treatment. Is used as a raw material. In the slag removal process, it is preferable to remove the slag in the slag as much as possible except for the unavoidable slag component. Usually, the iron (ingot) content in the slag is less than 3% by weight. It is preferable that

The reaction of CaO and CO ₂ with CaO ₃ , that is, consolidation using CaCO ₃ generated by a carbonation reaction, is a technique that has been known for a long time. When put down, the CaCO ₃ produced by the following reaction formula, resulting in consolidation phenomenon between the particles of the CaCO ₃ as the binder. CaO + CO ₂ → CaCO ₃

Conventionally, as a technique utilizing such a carbonation reaction, for example, a method of producing a hardened product such as a building material using a kneaded product of steelmaking crushed slag and water (for example, Japanese Unexamined Patent Application Publication No. -74559) and a method for producing unfired pellets (for example, see JP-A-57-92143 and JP-A-58-92143).
-48642, JP-A-58-133334) and the like. However, these prior arts are all intended only to produce a hardened product or a non-fired pellet having a required strength in a short period of time, and among powdery granular slag, coarse granular slag, and small massive slag, Stones obtained by consolidating slag consisting of at least one of the following, or powdery and / or coarse slag that has undergone ingot removal treatment by carbonation reaction, as a stone material for seaweed beds in terms of its properties and properties Nothing is shown as being a very suitable material.

Also, when the particulate matter containing MgO is placed in a carbon dioxide gas atmosphere, MgC is formed by a carbonation reaction.
O ₃ is generated, and a consolidation phenomenon occurs between the particles using the MgCO ₃ as a binder. MgCO ₃ generated by the carbonation reaction of MgO can be used in various forms such as anhydrate, hydrate (eg, dihydrate, trihydrate, pentahydrate, etc.) and hydroxide salt (basic magnesium carbonate). Although, for example, MgCO ₃
Is produced by the following reaction formula. _{MgO + CO 2 + 3H 2 O} → MgCO 3 · 3H 2 O

In general, slag generated in the steel making process contains a considerable amount (typically, 20 to 60% by weight) of Ca.
O is contained, and the artificial stone material is converted into slag composed of at least one of powdery slag, coarse slag, and small slag, or powdery and / or coarse slag that has undergone metal removal processing. CaO or this C contained
Ca (OH) ₂ having aO changed (including CaO and Ca (OH) ₂ optionally added) is converted into C by the above reaction.
It is changed to aCO _3, and the slag particles (additive particles and slag particles in the case of containing an additive) are solidified by using CaCO ₃ as a binder to form an agglomerate.

Most of the slag contains a certain amount of MgO together with CaO, and the artificial stone made from such slag is MgO or MgO.
O is (MgO to be added as required, including Mg (OH) ₂₎ was Mg (OH) ₂ changes varied MgCO ₃ by the carbonation reaction also, the MgCO ₃ and Ca
The slag particles (additive particles and slag particles when the additive is included) are consolidated using CO ₃ as a binder to form a mass.

As described above, MgCO ₃ generated by the carbonation reaction of MgO takes various forms such as anhydrides, hydrates, hydroxide salts and the like. MgCO included as _3, may be MgCO ₃ in any form of them. For example, Mg
As hydrates of CO ₃ , MgCO ₃ .2H ₂ O, MgC
O ₃ .3H ₂ O, MgCO ₃ .5H ₂ O, etc., and the hydroxide salt (basic magnesium carbonate) is MgCO 3.
₃・ Mg (OH) ₂・ 3H ₂ O, 4MgCO ₃・ Mg (O
_{H) 2 · 4H 2 O,} 4MgCO 3 · Mg (OH) 2 · 5H 2
O, 4MgCO ₃ .Mg (OH) ₂ .8H ₂ O and the like.
Further, MgCO ₃ may combine with other salts to form various double salts, and MCO existing in such a double salt form may be used.
It may be gCO ₃ .

In the slag generated in the steel making process, some or all of the CaO and MgO contained in the slag may absorb Ca (O 2 O) over time due to the absorption of moisture over time or other causes.
H) ₂ or Mg (OH) ₂ may be changed, but as described above, there is no problem as a slag used for artificial stone, and these Ca (OH) ₂ and Mg (OH) ₂ are also subjected to a carbonation reaction. The artificial stones are obtained by changing to CaCO ₃ and MgCO ₃ respectively.

This artificial stone is made of CaCO ₃ or CaCO ₃ produced by the carbonation reaction of slag having a small particle diameter and MgC ₃ .
Since it is tightly consolidated with O ₃ as a binder, it has sufficient strength, so even if it is shocked during transportation or sinking in the sea, or if it is placed in the sea for a long time, There is no risk of cracking or collapse.

In order to obtain a composition suitable for each of the artificial stone materials according to the conditions of the sea area to be applied, etc., a slag composed of at least one of powdery slag, coarse slag, and small slag, or Various additives (powder-granular, coarse-grained or small-lumped additives) can be contained together with the granular and / or coarse-grained slag. Examples of the additive include powder or coarse particles (soluble silica, soluble silica material) serving as a soluble silica source, and powder or coarse particles (metallic iron, metal-containing iron material, iron oxide, iron oxide) serving as an iron source. Iron oxide material), powdered or coarse CaO, and the like.
In addition, in order for artificial stone to contain CaO as an additive, at least a part of CaO contained in the slag or CaO significantly added to the slag is left as unreacted CaO even after carbonation and solidification. There is a need.

Soluble silica and iron sources (metallic iron and iron oxide) contained in the artificial stones effectively act on the growth of seaweeds when they elute into seawater. In addition, from the viewpoints of dissolution into seawater and the growth of seaweed, metallic iron and metallic iron-containing materials are particularly preferable among iron sources. However, in the case of artificial stone materials obtained from powdered and / or coarse-grained slag that has undergone ingot removal, which is applied to sea areas where deoxygenation of seawater or excessive supply of iron is a problem. No metallic iron or metallic iron material is added.

The CaO contained in the artificial stone in a small amount is
When the seabed contains a large amount of phosphorus that causes red tide and sulfur that causes blue tide, it is effective to adsorb these phosphorus and sulfur and prevent the generation of red tide and blue tide. As described above, when a large amount of CaO is contained in the stone, p
Although there is a problem that H rises and white sedimentation occurs, a small amount of C remaining after carbonation solidification is used to adsorb phosphorus and sulfur.
It is sufficient if aO is included.

Examples of the powdery or coarse-grained material serving as the soluble silica source include powdery or coarse-grained soluble silica and / or a soluble silica-containing material. As the soluble silica material, fly ash, clinker ash, or the like generated by coal combustion in a thermal power plant or the like can be used. Of these, fly ash is 45-75% by weight
To the extent that clinker ash contains about 50 to 65% by weight of soluble silica.

Further, since granulated blast furnace slag also contains a relatively large amount of soluble silica, part or all of the slag is made into granulated blast furnace slag, for example, a mixture of steelmaking slag and granulated blast furnace slag is used. Thereby, the same effect as in the case where an additive serving as a soluble silica source is added can be obtained.

Examples of the powdery or coarse-grained material serving as an iron source include powdery or coarse-grained metal iron or metal-containing iron material such as granular iron, and powdery or coarse-grained iron oxide or iron oxide-containing material. Particularly easily and inexpensively available powder or coarse particles include iron-containing dust and mill scale generated in a steelmaking process. Iron-containing dust is generally used as iron-containing dust. Usually, this dust contains about 75% of iron oxide in terms of Fe, and in some cases, about 60% of metallic iron. The mill scale also contains about 70% iron oxide in terms of Fe.

Further, as described above, when a stone material having a large specific gravity is laid on the seabed where sludge is deposited, the stone material sinks into the sludge and cannot serve as a stone material for seaweed beds. There are cases. Therefore, for stones used in sea areas where such sludge is deposited,
It is preferable to use slag having a relatively small specific gravity as a main raw material. Specifically, it is effective to use granulated slag having a small specific gravity as compared with other slags as at least a part of the main raw material. The artificial stone has a relatively porous property, whereby the effects described above can be obtained. Although the porosity of the stone is not particularly limited, it is usually 10 to 7
The porosity is preferably about 0%.

Next, a preferred method for producing the artificial stone will be described. FIG. 1 shows an example of a manufacturing flow of the artificial stone material, and FIG. 2 shows an example of a manufacturing process according to the manufacturing flow. Regarding slag generated in the steel making process, ingots in the slag are generally collected, and a considerable proportion of the ingot contained in the slag is removed. Usually, in this slag recovery process, slag is centrifuged by a crusher or the like.
Particle size of order or smaller (eg, 5 cm or less)
After the slag is ground to a powdery, coarse, or small slag, the slag is collected. The slag only needs to have a particle size capable of recovering the slag.Therefore, if the slag can be recovered even if the particle size is relatively coarse due to the properties of the slag, etc. May be crushed.

In the above-described slag collection, the slag content in the slag after the collection process does not have to be as low as after the slag removal process described later, and an appropriate amount of the slag may be left. This is because iron contained in slag (especially metallic iron and metallic iron-containing materials) elutes into seawater, so that iron is replenished as a nutrient in seawater, which effectively acts on the growth of seaweeds. Because. For this reason, it is usually sufficient to recover the slag to such an extent that 3% by weight or more of the ingot remains in the slag after the recovery process.

Further, some slags are carried in a state in which the slag is naturally collapsed to a particle size capable of recovering the metal (ie, a state in which the slag is naturally collapsed into a powdery, coarse, or small lump). In some cases, the above-mentioned pulverizing treatment is not necessary for a fine slag. For example, after the unslagged CaO contained in the slag is cooled and solidified, the slag reacts with moisture or rainwater in the air, water spray during cooling, etc., to cause Ca (O).
H) ₂ is produced, during which the slag expands and collapses,
When powdered or in a slag having a basicity (CaO / SiO ₂ ) close to 2, 2CaO · SiO ₂ (C ₂ S) is generated, and this C ₂ S undergoes transformation expansion in the slag cooling process, and the slag is formed. The slag may be disintegrated, powdered, or the like, and the slag that has been powdered, granulated, or compacted to a particle size that is already capable of recovering the slag can be directly subjected to the slag recovery. .

Usually, the slag is recovered by magnetic separation using a magnetic separator (a method of removing the metal in the slag using a magnet). However, the present invention is not limited to this. It is also possible to use a specific gravity selection method such as a wind power separation utilizing a specific gravity difference between the gold component and the slag component. By this metal recovery, a considerable amount of metal components contained in the slag are recovered. In FIG. 2, 1 is a crusher,
Reference numeral 2 denotes a magnetic separator.

The slag that has undergone the above-described metal recovery is one of powdery slag, coarse slag, and small slag.
It is a slag composed of more than one species and sent to the next step, the carbonation solidification step or its pretreatment step. However, the raw material slag is one of powder granular slag, coarse granular slag, and small massive slag.
More than one kind is required, and therefore, it is not a necessary condition to go through the above-described bullion collecting step.

In general, most of the slag that has passed through the slag recovery step contains powder slag particles or coarse slag particles at a certain ratio or more, though varying in degree. Even if small-sized slag particles with large diameters are mixed, the gaps between the small-sized slag particles are filled with powdery or coarse slag particles, so that the slag particles are carbonized and solidified to a state having a predetermined strength. There is almost no risk of disruption. However, when the slag is substantially composed of only small slag particles or when the ratio of the small slag particles in the slag is relatively large, the contact area between the slag particles becomes small. There is a possibility that a problem may occur in solidifying carbon dioxide to a state having a predetermined strength. Therefore, in such a case,
It is preferable to carry out particle size adjustment such as increasing the ratio of powdery or coarse slag particles.

The iron in the slag may be left without recovering part or all of the metal (granular iron or the like) originally contained in the slag as described above, and this may be used as it is. As described above, the content of iron contained in the slag is arbitrarily controlled, and the shape and size of the iron contained in the slag are arbitrarily selected, and a preferred iron source such as granular iron is slag. In order to be contained in the slag, once the slag is substantially all of the metal (except for unavoidable slag)
It is preferable to adopt a method of removing metallic iron and / or metallic iron and / or metallic iron-containing material as an additive after the metal is removed by a metal removal treatment.

As will be described later, the slag removal processing is generally performed in a state where the slag is crushed by a crusher or the like to a particle size of mm order or smaller (for example, 5 mm or less). However, the slag only needs to have a particle size that enables the slag removal treatment. Therefore, if the slag can be removed even if it is relatively coarse due to the properties of the slag, etc. The slag may be crushed. In addition, slag that has already been pulverized or coarsened by natural pulverization or the like may not require the above-described pulverization treatment.
In the ingot removal process, it is preferable that the ingot in the slag is removed as much as possible except for the inevitable remaining ingot component. Usually, the ingot content rate in the slag after the ingot removal process is 3%. It is preferred that the amount is less than the weight%.

Usually, the metal removal processing is performed by magnetic separation (a method of removing metal in slag by a magnet) using a magnetic separator or the like, but is not necessarily limited to this. A specific gravity selection method such as a wind power separation utilizing a specific gravity difference between the component and the slag component can also be used.

Then, to the slag that has undergone such a metal removal treatment, an appropriate amount of metallic iron such as granular iron and / or a metal-containing iron material is added, and the desired iron content including the metal iron and the metal-containing iron material is adjusted. Slag is obtained. The slag thus obtained is a powdery and / or coarse-grained slag containing an appropriate amount of metallic iron and / or a metallic iron-containing material, and the slag is a carbonation solidification step or a pretreatment step of the next step. Sent to As the metallic iron or metallic iron-containing material to be added to the slag, granular iron is most suitable for the reasons described above. As the granular iron, not only the granular iron recovered from the slag but also any other granular iron that can be procured can be used.

FIG. 3 shows an example of a production flow when an artificial stone is manufactured without adding metallic iron or a metal-containing iron material after slag is subjected to ingot removal treatment, and FIG. 4 is in accordance with the production flow. 1 shows an example of the manufacturing process. In this case, the slag generated in the steel manufacturing process is first subjected to a metal removal treatment to remove a major metal (grain iron) component.
Generally, since the slag component and the metal in the slag are mixed in a state of being closely entangled, it is necessary to perform the metal removal treatment in the form of slag in the form of powder or coarse particles.
Usually, slag is crushed by a crusher or the like to a particle size of mm order or smaller (for example, 5 mm or less), and then a slag removal treatment is performed. However, the slag only needs to have a particle size that enables the slag removal treatment. Therefore, if the slag can be removed even if it is relatively coarse due to the properties of the slag, etc. The slag may be crushed.

In this metal removal processing, it is preferable that the metal in the slag is removed as much as possible, except for the metal components inevitably remaining. Usually, the metal in the slag after the metal removal processing is removed. Preferably, the content is less than 3% by weight. In addition, as described above, some slags are carried in a state of natural powdering or granulation to a particle size capable of removing metal, and such slags require the above-described pulverization treatment. Not always. The cause of the natural powdering of slag is as described above. For these reasons, slag that has already been powdered or granulated to a particle size capable of removing slag is directly subjected to slag removal treatment. Can be applied.

Usually, the metal removal processing is performed by magnetic separation (a method of removing metal in slag by a magnet) using a magnetic separator or the like, but is not necessarily limited to this. A specific gravity selection method such as a wind power separation utilizing a specific gravity difference between the component and the slag component can also be used. By this metal removal processing, a main metal component in the slag is removed. In FIG. 3, 1 indicates a crusher and 2 indicates a magnetic separator. The slag that has undergone the above-described metal removal treatment is a powdery and / or coarse-grained slag, and this slag is sent to the next step, the carbonation solidification step or its pretreatment step.

The slag composed of one or more of the above-mentioned powdery and granular slag, coarse-grained slag and small-lumped slag, or powdery and / or coarse-grained slag that has been subjected to a metal removal treatment may be used, if necessary. When CaO and MgO required for the carbonation reaction are insufficient in the slag, CaO, Ca (OH) ₂ ,
At least one selected from MgO and Mg (OH) ₂ is added and mixed with the slag. Examples of the additive include powder or coarse particles serving as a soluble silica source (soluble silica, soluble silica material), and powder or coarse particles serving as an iron source (metallic iron, metal-containing iron material, iron oxide, oxidized oxide) Iron), CaO
And the like can be added, and specific examples thereof are as described above.

Among these, soluble silica and iron sources (metallic iron, iron oxide) are effective in growing seaweeds by eluting them into seawater. In addition, from the viewpoints of dissolution into seawater and the growth of seaweed, metallic iron and metallic iron-containing materials are particularly preferable among iron sources. However, in the case of artificial stone materials obtained from powdered and / or coarse-grained slag that has undergone ingot removal, which is applied to sea areas where deoxygenation of seawater or excessive supply of iron is a problem. No metallic iron or metallic iron material is added.

The method of mixing the slag with the additive material such as the additive or CaO is, for example, a method of mixing the slag and the additive material discharged from a slag collection facility or a slab removal treatment facility in a hopper. Any method may be adopted, such as a method of adding and mixing additional raw materials to slag that has undergone metal recovery or metal removal processing in a metal recovery or metal removal processing facility, or a method of mixing with shovels or other heavy equipment. it can. At this stage, the slag can also be adjusted for moisture as needed. This moisture adjustment will be described later in detail.

[0093] The slag to which the additives and the like are added and mixed as necessary and the water content of which is adjusted as described above is piled up or filled in an arbitrary space for carbonation and solidification. Here, when piled up slag, the pile may be piled up. It is preferable to cover with.

For pile-up or filling of slag, for example, a pit surrounded by partition walls on three sides, a formwork or a container surrounded by partition walls on four sides, or the like can be used. Also in the case where slag is piled up or filled in the pits, it is preferable to cover the pile or the filling layer with a sheet or the like as in the case of the above-mentioned open stacking. Also, when using a mold or a container, it is preferable to cover the slag filling layer with a sheet or to provide a lid. FIG. 2 and FIG.
The state where the filling layer A is formed inside the mold 3 is shown.

The stacking amount or filling amount of the slag is not particularly limited, and may be, for example, a stacking amount or filling amount of several to several hundred tons, or a stacking amount or filling amount corresponding to about one to several tens of stone materials. It may be the filling amount,
The amount is arbitrary. However, even if the amount of piles or the amount of slag is large, it is possible to easily cut out massive stones by crushing the pile or the packed bed after carbonation with a heavy machine or the like. The lumpy stone material has an advantage that it has an uneven fracture surface which is advantageous for the adhesion of seaweed. Therefore, from the viewpoint of productivity and function as a stone material for a seaweed bed, it is preferable that the pile amount or the filling amount of the slag is somewhat large.

It is preferable to adjust the pile density of slag or the bulk density (pressure density) of the packed bed according to the density of the stone material to be produced. That is, the density of the seaweed bed stone is preferably adjusted according to the state of the seabed and the like.For example, when the seabed is muddy or sludge, the stone is relatively low so as not to sink into the mud or sludge. It is preferable to use a stone having a high density. On the other hand, when the seabed is a rocky reef or the like, it is preferable to use a stone having a relatively high density in order to prevent the stone from flowing into an ocean current. In addition, depending on the degree of porosity (porosity) of the stone, the degree of adhesion and growth of seaweed and the degree of elution of the active ingredient from the inside of the stone also differ. In some cases, it is preferable to adjust the degree of porosity.

The density of the artificial stone material depends on the pile density of the slag or the bulk density (consolidation density) of the packed bed.
The density of the stone material can be easily adjusted by adjusting the degree of compaction of the pile of slag or the packed layer as necessary as described above and adjusting the bulk density.
The degree of compaction of the pile of slag or the packed bed is arbitrary, but usually the bulk specific gravity / true specific gravity is in the range of 0.3 to 0.9, that is, the porosity in the pile or packed bed is 70 to 1.
Compaction is performed to an extent of 0%.

For compaction of the pile or packed bed of slag, a method of compacting the pile or packed bed from above by a heavy machine, a method of compacting by applying vibration to the pile or packed bed, or the like can be adopted. By adjusting the degree of compaction at the time of performing, the pile density or the bulk density of the packed bed is adjusted. Further, in the case of producing a low-density stone material, carbonization can be carried out while slag is piled up or filled without compaction.

As a specific method of compaction, for example, when compaction is performed on a pile or a packed layer in a pit, a mold or a container as described above, a target is placed inside the pit, the mold or the container. A weighing line indicating the volume of the slag is displayed, slag of a known weight is put in the slag, and then compaction is performed until the top of the pile or the packed layer reaches the height of the weighing line.

After the adjustment of the bulk specific gravity of the slag pile or the packed bed as described above is completed, a carbonation reaction is caused in the pile or the packed bed in the presence of carbon dioxide gas to solidify the slag with carbon dioxide. Specifically, a carbon dioxide gas or a carbon dioxide-containing gas is blown into a pile or a packed bed of slag,
Alternatively, the pile or the packed layer is placed under a carbon dioxide gas or a carbon dioxide-containing gas atmosphere, and the slag is carbonized and solidified.

There is no particular limitation on the method of blowing carbon dioxide gas or carbon dioxide-containing gas into the pile or the packed bed.
Gas blowing means is provided at the bottom of the pile or packed bed,
It is most effective to blow gas through this gas blowing means. Specifically, gas supply pipes or hoses are arranged at an appropriate density on the bottom of the pile or the packed layer (when using pits, formwork or containers, etc., their floors). Carbon dioxide gas or carbon dioxide-containing gas can be blown out from gas blowout holes provided at an appropriate pitch (for example, a pitch of 30 to 300 mm × 40 to 400 mm) in a pipe or a hose.

As a method of placing a pile or a packed layer in a carbon dioxide gas or a carbon dioxide-containing gas atmosphere, the pile or a packed layer is placed in an airtight space (including a container or the like).
A method of supplying a carbon dioxide gas or a carbon dioxide-containing gas into this space in an arbitrary mode can be adopted. As the carbon dioxide-containing gas used, for example, a lime burning plant exhaust gas (usually, CO ₂ : about 25%) or a heating furnace exhaust gas (usually, CO ₂ : about 6.5%) discharged in an integrated steel mill is used. Suitable, but not limited to. In addition, if the concentration of carbon dioxide in the carbon dioxide-containing gas is too low, there is a problem that the processing efficiency is reduced, but other problems are not particularly significant. Therefore, the concentration of carbon dioxide is not particularly limited, but is preferably 3% or more for efficient processing.

There is no particular limitation on the amount of carbon dioxide gas or gas containing carbon dioxide gas to be blown, and gas may be blown to such an extent that the pile of slag or the packed bed does not flow. As a general guide, 0.004-0.5m ³ / m
It suffices if a gas blowing amount of about int can be secured. There is no particular restriction on the gas blowing time (carbonation time), but as a guide, the time when the amount of carbon dioxide gas (CO ₂ ) blows becomes 3% or more of the weight of the slag, that is, converted into the gas amount. Then, it is preferable to perform gas blowing until carbon dioxide (CO ₂ ) of 15 m ³ or more per 1 t of material is supplied.

The carbon dioxide gas or carbon dioxide-containing gas blown into the pile of slag or the packed bed may be at room temperature. However, if the gas is at a higher temperature than room temperature, it is advantageous because the reactivity increases accordingly. However, if the gas temperature is excessively high, CaC
O ₃ is decomposed into CaO and CO ₂ , and MgCO ₃ is also converted into MgO
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.

[0105] Further, moisture is necessary for carbonizing and solidifying slag by utilizing the reaction between CaO and MgO and carbon dioxide gas, and the optimum amount of water varies depending on the particle size of the slag. Water content of 3-10%
It is appropriate to set the range. This is Ca
This is because the carbonation reaction is promoted by dissolving O, MgO and carbon dioxide gas. Therefore, it is preferable to adjust the water content of the slag to an optimum water content as needed, and then to cause a carbonation reaction in the presence of carbon dioxide gas.
For this reason, if the water content of the slag is too low, for example,
It is preferable to add water to the slag in the mixing process and the like shown in the production flow of FIGS. 1 and 3 and to perform water adjustment such as increasing the water content of the slag.

The optimum water content (moisture content) of the slag means, for example, the form of water present in the pile of the slag or the inside of the packed bed. A thin water film is formed on the surface of each slag particle. And a state in which water films of adjacent slag particles are partially in contact with each other, and a gas flow path for supplying carbon dioxide to the water film surface of each slag particle surface is secured. It is considered to be.

The optimum moisture content (moisture content) of the raw material slag to be used can be determined, for example, as follows. Water absorption (JIS A)
A raw material slag sample of three or more levels is prepared by adding an arbitrary amount of water equal to or greater than the fine aggregate or coarse aggregate specified in 1109 or A 1110), and each raw material slag sample is dried with pores. Fill the mold so that the rate is constant. After humidifying carbon dioxide at a predetermined temperature in the range of 10 to 40 ° C. through a water bath or the like, the slag is blown into the slag packed bed from the bottom of the mold at a constant supply amount and supply time to carbonate and cure the slag. And solidify. Thereafter, the compressive strength of each solidified massive slag (stone block) is measured, and for example, the relationship between the water content of the raw material slag and the compressive strength as shown in FIG. 5 is obtained, and the maximum value of the compressive strength is obtained. The water content of the raw material slag is set as the optimum water content of the raw material slag, and the water content of the raw material slag is adjusted.

FIG. 5 shows the relationship between the water content of the raw material slag and the compressive strength of the produced massive slag (stone) based on the results of an experiment conducted to examine the effect of the water content of the raw material slag. . In this experiment, the basicity (CaO / S
A steelmaking slag having an iO ₂ of 4 was pulverized to 5 mm or less, and water was added to the slag to adjust the water content to several levels.
The slag having a moisture content of these several levels was filled in the mold, carbon dioxide gas was supplied to the slag packed bed from the bottom of the mold at a supply rate of 0.5 L / min · kg, and the slag was solidified by carbonation. .

The size of 1 m ×
As a result of measuring the compressive strength of a 1 m × 1 m stone block (mass slag), a relationship between the water content of the raw material slag and the compressive strength of the stone block as shown in FIG. 5 was obtained. Among Although raw slag stone blocks obtained by dampening water content a ₁ two tone has the highest compressive strength, stone blocks obtained raw slag dampening water content a ₂ two-tone is a leaving When I grabbed the bucket after the frame and tried to move, it collapsed relatively easily.

When supplying carbon dioxide gas or carbon dioxide-containing gas to the pile or packed bed of slag, carbon dioxide gas or carbon dioxide-containing gas is blown into water once to saturate H ₂ O, By blowing the slag into the mountain or the packed bed, the slag can be prevented from drying and the carbonation reaction can be promoted. By supplying carbon dioxide or a carbon dioxide-containing gas into the pile of slag or the packed bed as described above, CaO (or Ca (OH) ₂ ), MgO (or Mg
(OH) ₂ ) reacts with carbon dioxide to produce CaCO ₃ , M
gCO ₃ is produced, and this CaCO ₃ or CaCO ₃ and M
gCO ₃ as a binder and slag particles (slag particles and additive particles when additives are mixed)
Solidifies.

After the completion of carbonation solidification, the pile or the packed bed is crushed to an appropriate size by a heavy machine or the like, if necessary, and a massive artificial stone is cut out. Therefore, a stone material of any size can be obtained depending on the size at the time of cutting. Usually, massive stones are 80-1500mm
It is cut out to the size of. In addition, the crushing at the time of cutting causes a rough surface having irregularities on which the seaweeds easily adhere to the stone. In addition, by making the volume of the packed bed small enough,
It can also be used as a stone as it is without cutting it out as described above.

[0112] Such a manufacturing method has the following advantages. Easy to adjust the density of stones for seaweed beds by adjusting the degree of compaction of the pile or packed bed and adjusting its bulk specificity to perform carbonation solidification with the slag as a pile or packed bed Can be done. As described above, it is preferable that the density of the seaweed bed stones and the degree of porosity are appropriately adjusted in accordance with the condition of the seabed and the current, and that such adjustment can be arbitrarily and extremely easily performed. This is a great advantage in obtaining stones for seaweed beds. As a conventional technique, a technique of carbonizing and solidifying granulated pellets and the like is known, but it is difficult to adjust the density of the non-treated material in a wide range by such a granulation method.

[0113] Carbonation solidification is performed in a state where the slag is formed as a pile or a packed bed, and after completion of carbonation and solidification, the pile or the packed bed is crushed into an appropriate size to cut out a massive stone material having a desired size, or Can be used as a massive stone as it is, and by appropriately selecting the size of the cut stone and the size of the packed bed, a stone having an arbitrary size (for example, 80 to 1500 mm) can be obtained. A large lump of stone, which is particularly preferable as a site stone, can be easily obtained. In the above-described conventional technology for carbonizing and solidifying the granulated pellets and the like, the size of the obtained lump is limited to about 30 to 50 mm at most, and the lump inevitably also has a small size. Therefore,
The fact that large blocks of stone can be obtained as in this production method is a great advantage as a method for producing stones for seaweed beds.

After carbonation and solidification, a pile of slag or a packed bed is crushed by a heavy machine or the like, and a method of cutting out a massive stone material is employed, whereby a massive stone material having an uneven surface (fracture surface) on which seaweeds can easily form. Can be obtained.

[0115]

【Example】

[Example 1] Mortar is poured into a mold having a size of 1.5m x 1.5m x 1.5m, and the hardened concrete block is divided into two pieces by a breaker (rock drill), so that seaweeds are easily formed. Stone materials for the seed material having a crushed surface and for the seaweed bed development base were obtained. One of the stones was transported to the sea where a natural seaweed bed was located, and was temporarily placed in the seaweed bed with the crushed surface of the stone facing upward, while being placed in a net for lifting. In order to prevent the sediment in the sea from covering the surface of the stone before the spores of the seaweed adhere,
September was selected immediately before spores were released from the seaweed in the seaweed bed. Approximately one year later, it was confirmed that seaweeds grew on the surface of the stone and the rooting was stable, so this stone was pulled up to the sea and collected, and this was used as seed material for seaweed bed development. Was immediately transported to a seaweed bed creation site (shaded so as not to dry, and transported while spraying water).

The seabed with a depth of 4 m, which is sufficiently distant from the existing seaweed beds, was selected in consideration of water quality, ocean currents, etc. At the site of this seaweed bed, 20 new stones on which seaweeds had not set were laid down in a range of about 10 m in diameter with the crushed surface on the top, and the seed material was settled in the center thereof. . About 1 site for this seaweed bed
Investigations made a year later confirmed that seaweeds had proliferated and grown sufficiently on all stones surrounding the seed material.
As a result of the survey of seaweeds, 521 g /
It was found that m ² seaweeds were growing.

[Example 2] The maximum particle size of the slag particles was about 3
Converter slag powder having a particle size distribution of 0 mm and having a particle size distribution of about 70% by weight of slag particles having a particle size of 5 mm or less (a slag including a small-lumped slag that has undergone a metal ingot recovery treatment, an iron content:
12% by weight) in a pit having a width of 4 m and a depth of 6 m, piled up to a height of 1.5 m and compacted appropriately, then the pit was sealed, and carbon dioxide was supplied at a supply rate of 23 Nm ³ / hr for 6 days. The slag was blown and solidified by carbonation. The carbonized and solidified slag is crushed and divided by a heavy machine, and has a size of approximately 1.0 m to 1.5 m as a material for seed material and for a seaweed bed creation base.
Of 15 block stones were obtained.

One of the above-mentioned massive stone materials was transported to the sea where the same natural seaweed bed as in Example 1 was placed, and was temporarily placed and settled in the seaweed bed in a state of being put in a net for lifting. In order to prevent the sediment in the sea from covering the stone surface before the spores etc. of the seaweed adhere to the stone, the time of this stone settlement is September, just before the spores are released from the seaweed in the seaweed bed. I chose. Approximately one year later, it was confirmed that seaweeds grew on the surface of the stone and the rooting was stable, so this stone was pulled up to the sea and collected, and this was used as seed material for seaweed bed development. Was immediately transported to a seaweed bed creation site (shaded so as not to dry, and transported while spraying water).

The same sea area and water depth as in Example 1 were selected for the seaweed bed creation site. At the place where this seaweed bed is created,
14 new stones with no seaweed on
The seed material was settled in a range of 0 m, and the seed material was settled in the center. A survey of the place where this seaweed bed was created was conducted about one year later, and as a result, it was confirmed that seaweeds had proliferated and grown sufficiently on all stones surrounding the seed material. As a result of survey of seaweeds, it was found that seaweeds with a wet weight of 653 g / m ² grew.

[Example 3] Converter slag powder having a particle size of 3 mm or less (slag powder having been subjected to metal removal treatment, iron content: 2 wt%)
%) In a pit having a width of 4 m × a depth of 6 m and a height of 1.5 m and suitably compacted, the pit is sealed, and carbon dioxide gas is blown in at a supply rate of 50 Nm ³ / hr for 3 days. The slag was carbonated. The carbonated and solidified slag was crushed and divided by a heavy machine to obtain fifteen massive stone materials having a size of approximately 1.0 m to 1.5 m as materials for the seed material and the seaweed bed creation base.

One of the above-mentioned massive stone materials was transported to the sea where the same natural seaweed bed as in Example 1 was placed, and was temporarily placed and settled in the seaweed bed in a state where it was placed in a net for lifting. In order to prevent the sediment in the sea from covering the stone surface before the spores etc. of the seaweed adhere to the stone, the time of this stone settlement is September, just before spores are released from the seaweed in the seaweed bed. I chose. Approximately one year later, it was confirmed that seaweeds grew on the surface of the stone and the rooting was stable, so this stone was pulled up to the sea and collected, and this was used as seed material for seaweed bed development. Was immediately transported to a seaweed bed creation site (shaded so as not to dry, and transported while spraying water).

The same sea area and water depth as in Example 1 were selected for the seaweed bed creation site. At the place where this seaweed bed is created,
14 new stones with no seaweed on
The seed material was settled in a range of 0 m, and the seed material was settled in the center. A survey of the place where this seaweed bed was created was conducted about one year later, and as a result, it was confirmed that seaweeds had proliferated and grown sufficiently on all stones surrounding the seed material. Result of performing Tsubogari investigation of seaweed, seaweed of 689g / m ² in the wet weight was found to be growing.

[0123]

As described above, according to the method of the present invention, the selection range of the seaweed bed formation site is wide, and the seaweed bed can be reliably formed in a relatively short period of time with little labor and cost. It is possible to construct large-scale seaweed beds easily. Further, in particular, according to the method of the present invention according to Claims 2 to 15, while effectively utilizing slag generated in the steelmaking process, seaweeds can be reduced without increasing the pH of seawater or causing white precipitation on the stone surface. Since it can be grown efficiently and the material itself for submerging can be manufactured at low cost, the creation of a seaweed bed can be performed more efficiently and at lower cost.

[0124] Among them, according to the method of the present invention using an artificial stone made from slag that has undergone ingot removal treatment,
In addition to the above effects, in the sea areas where it is necessary to suppress the oxygen depletion of seawater due to the oxidation of iron and the excessive supply of iron to seawater, the oxygen depletion of the seawater due to the oxidation of iron and the iron content in the seawater Excessive supply can be effectively suppressed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an example of a production flow of an artificial stone material suitable for a material used in the method of the present invention.

FIG. 2 is an explanatory view showing a specific example of a manufacturing process of the artificial stone according to the manufacturing flow of FIG.

FIG. 3 is an explanatory view showing another example of a production flow of an artificial stone material suitable for a material used in the method of the present invention.

FIG. 4 is an explanatory view showing a specific example of a manufacturing process of an artificial stone according to the manufacturing flow of FIG. 3;

FIG. 5 is a graph schematically showing the relationship between the water content of a raw material slag and the compressive strength of a manufactured stone.

[Explanation of symbols]

 1 ... crusher, 2 ... magnetic separator, 3 ... formwork, A ... packed bed

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Norio Isoo 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nihon Kokan Co., Ltd. (72) Inventor Minoru Fukuhara 1-1, Odaimachi, Okayama City, Okayama Prefecture Okayama University of Science Inside

Claims (15)

[Claims] [Claim 1] A material consisting of a heavy substance is temporarily placed and settled on an existing seaweed bed, seaweeds are grown and grown on the surface of the material, and then the material is collected to form a seaweed bed. Alternatively, the seed material is relocated to a place where the seaweed is to be proliferated, and another material on which the seaweed is to be grown is disposed around the seed material, and the seaweed of the seed material is proliferated to the other material. A method for constructing or improving a seaweed bed, comprising: 2. A stone material mainly composed of slag generated in a steel manufacturing process as a material, wherein the slag is composed of at least one of powdery slag, coarse slag, and small slag. Produced by the carbonation reaction
The method according to claim 1, wherein a mass of artificial stone material obtained by consolidating CO ₃ as a binder is used. 3. A stone material, which is mainly made of slag generated in a steel manufacturing process as a material, wherein the slag is at least one of powdery slag, coarse slag, and small slag. Produced by the carbonation reaction
An artificial stone material obtained by consolidating CO ₃ and MgCO ₃ (including the case where MgCO ₃ is present as a hydrate, a hydroxide salt or a double salt) as a binder and using the aggregated stone. 2. The method for creating or improving a seaweed bed according to 1. 4. A stone material mainly composed of slag generated in an iron and steel manufacturing process and a granular and / or coarse-grained additive, wherein the slag is a granular slag;
Use of an artificial stone material that is made of at least one of coarse-grained slag and small-lumped slag, and solidifies a mixture of the slag and the additive with CaCO ₃ generated by a carbonation reaction as a binder, and is aggregated. The method for creating or improving a seaweed bed according to claim 1, wherein 5. A stone material mainly composed of slag generated in an iron and steel manufacturing process and a powdery and / or coarse-grained additive material, wherein the slag is a powdery slag;
CaCO ₃ and MgCO ₃ (including MgCO ₃₎ composed of at least one of coarse-grained slag and small-lumped slag, wherein a mixture of the slag and the additive is formed by a carbonation reaction.
2. The method according to claim 1, wherein the artificial stone is used as a hydrate, a hydroxide salt or a double salt. Method. 6. The method according to claim 4, wherein at least a part of the additive as a raw material of the artificial stone material is at least one selected from iron metal, metal-containing iron material, iron oxide, and iron oxide-containing material. 5. The method for creating or improving a seaweed bed according to 5. 7. The seaweed bed according to claim 2, 3, 4 or 5, wherein the slag as a raw material of the artificial stone is made of powdery and / or coarse-grained slag that has undergone a metal removal treatment. Creation or improvement method. 8. The slag as a raw material of the artificial stone is made of powdery and / or coarse slag subjected to a metal removal treatment, and at least a part of the additive is made of iron oxide and / or iron oxide-containing material. The method for constructing or improving a seaweed bed according to claim 4 or 5, wherein the method comprises the steps of: 9. The method according to claim 9, wherein the slag as a raw material of the artificial stone comprises powdery and / or coarse-grained slag that has undergone ingot removal treatment, and at least a part of the additive comprises metallic iron and / or metal-containing iron. The method for constructing or improving a seaweed bed according to claim 4 or 5, wherein the method comprises the steps of: 10. The method of claim 6, 8, or 9, wherein the metal-containing iron material and / or iron oxide-containing material, which is a raw material of the artificial stone material, comprises iron-containing dust and / or mill scale. Improvement method. 11. The method according to claim 4, wherein at least a part of the additive as a raw material of the artificial stone material is made of soluble silica and / or soluble silica material.
The method for creating or improving a seaweed bed according to 8, 9, or 10. 12. The method for creating or improving a seaweed bed according to claim 11, wherein the soluble silica material, which is a raw material of the artificial stone material, comprises fly ash and / or clinker ash. 13. At least a part of the additive as a raw material of the artificial stone is made of CaO, Ca (OH) ₂ , MgO, Mg (O
H) The method according to claim 4, 5, 6, 7, 8, 9, 10, 11, or 12, wherein the method comprises at least one selected from the group consisting of ₂ ). 14. The blast furnace slag according to claim 2, wherein at least a part of the slag as a raw material of the artificial stone is made of granulated blast furnace slag. 1
14. The method for creating or improving a seaweed bed according to 2 or 13. 15. The porosity of the artificial stone material is 10 to 70%.
The method for creating or improving a seaweed bed according to 8, 9, 10, 11, 12, 13 or 14.