TW202102462A - Aquaculture material and method of producing the same - Google Patents

Abstract

Provided are: a raw material for culturing which promotes growth of diatoms in water by supplying silicic acid to water, suppresses deterioration of water quality in fish ponds and the like, can achieve an improvement in growth of aquatic organisms that consume diatoms as food, serves as a source of calcium for aquatic organisms, and exhibits excellent particle size retention properties; and a method for producing same. This raw material for culturing comprises a granule of a porous cured body that contains calcium silicate hydrate, which is a product of a reaction between a siliceous raw material and a calcareous raw material, and unreacted calcareous raw material. The content of calcium carbonate in the porous cured body is 0.1-12.0 mass%. Also provided is a method for producing a raw material for culturing, the method including: a step for preparing a slurry using a siliceous raw material, a calcareous raw material, calcium carbonate, a foaming agent and water as raw materials; a step for obtaining a porous cured body by aging, foaming and curing the slurry; a step for obtaining a post-hydrothermal reaction porous cured body by subjecting the porous cured body to a hydrothermal reaction; and a step for obtaining the raw material for culturing by granulating the post-hydrothermal reaction porous cured body.

Description

Material for breeding and its manufacturing method

The invention relates to a material for breeding and a manufacturing method thereof.

As a method of improving the growth environment of aquatic organisms, various methods are known. For example, Patent Document 1 describes a culture solution for promoting the propagation of diatoms, which is characterized by promoting the growth of diatoms and allowing the growth of crustaceans, shellfish, animal plankton, etc. that use diatoms as bait A better culture medium contains powdery granular silicic acid material containing water and calcium silicate hydrate as main components, and the amount of the above-mentioned silicic acid material is 0.001 to 2 parts by mass per 100 parts by mass of water. In addition, Patent Document 2 describes a material for aquaculture, which is characterized by being able to further promote the propagation of diatoms in the water, and in a culture pond or enclosed waters, it can inhibit the deterioration of water quality, and improve the survival rate of aquatic organisms. The aquaculture material is a culture material containing calcium silicate used to supply the water used for the culture of aquatic organisms, wherein the water-soluble SiO ₂ dissolution when the above-mentioned culture material is added in an amount of 1 g relative to 1 liter of distilled water The amount is 3 mg or more. [Prior Technical Document] [Patent Document]

[Patent Document 1] JP 2015-167538 A [Patent Document 2] JP 2016-129512 A

[The problem to be solved by the invention]

The purpose of the present invention is to provide a method that promotes the reproduction of diatoms in the water by supplying silicic acid to the water, can inhibit the deterioration of water quality in aquaculture ponds, etc., and can enhance the growth of aquatic organisms that use diatoms as bait, and at the same time act as a calcium pair A source of aquatic organisms and excellent particle size retention for aquaculture materials and their manufacturing methods. [Means to solve the problem]

The inventors of the present case have worked hard to solve the above-mentioned problems. As a result, they found that based on the reaction product of a silicic acid raw material containing calcium silicate hydrate and unreacted lime raw material and a calcareous raw material, the content of calcium carbonate is 0.1～ The aquaculture material composed of 12.0% by mass of porous hardened granules can achieve the above-mentioned object, and the present invention has been completed.

The present invention provides the following [1] to [6]. [1] A material for aquaculture, characterized by being composed of porous hardened granular bodies, the granular system comprising calcium silicate hydrate and unreacted calcareous raw material, which is a reaction product of silicic acid raw material and calcareous raw material, The content of calcium carbonate is 0.1 to 12.0% by mass. [2] The material for aquaculture as described in [1] above, wherein the material for aquaculture contains granules with a particle size of 0.5-5 mm in a proportion of 50% by mass or more. [3] The material for aquaculture as described in [1] or [2], wherein the porous hardened body particle system is a porous carbonated particle obtained by carbonating the reaction product of a silicic acid raw material and a calcareous raw material body. [4] A method for manufacturing aquaculture material, which is used to manufacture the above-mentioned [1] or [2] method for aquaculture material, characterized by comprising: a slurry preparation step, which uses the above-mentioned silicic acid raw material, The lime raw material, calcium carbonate, foaming agent and water are used as raw materials to prepare a slurry; the hardening step is to mature the slurry to foam and harden to obtain a porous hardened body; the hydrothermal reaction step is Hydrothermally reacting the porous hardened body to obtain a porous hardened body after the hydrothermal reaction; and a granulation step of granulating the porous hardened body after the hydrothermal reaction to obtain the above-mentioned culture Use materials. [5] A method for manufacturing aquaculture material, which is used to manufacture the above-mentioned [3] aquaculture material, characterized by comprising: a slurry preparation step, which uses the above-mentioned silicic acid raw material and the above-mentioned calcareous raw material , Foaming agent and water are used as raw materials to prepare the slurry; the hardening step is to mature the above-mentioned slurry, foaming and hardening to obtain a porous hardened body; the hydrothermal reaction step is to make the above-mentioned porous hardened body Hydrothermal reaction occurs to obtain a porous hardened body after hydrothermal reaction; and a granulation and carbonation step, which uses the porous hardened body after the hydrothermal reaction to obtain the above-mentioned material for cultivation, and the above-mentioned The granulation and carbonation step is a method of (a) granulating the porous hardened body to obtain a porous plasmid, and then carbonating the porous plasmid to obtain the material for cultivation, or (b) After the porous hardened body is carbonated to obtain a porous carbonated hardened body, any one of the methods of obtaining the above-mentioned material for cultivation by granulating the porous hardened carbonated body. [6] The method for producing aquaculture materials as described in [4] or [5], wherein the silicic acid raw material contains at least one selected from the group consisting of silica, silica sand and diatomaceous earth, and the calcareous raw material contains selected One or more of quicklime, slaked lime, and cement, and the above-mentioned foaming agent includes aluminum powder. [Effects of Invention]

Since the culture material of the present invention is porous and contains calcium silicate hydrate, by supplying water-soluble silicic acid to the water, the propagation of diatoms in the water can be promoted. In addition, as a result of promoting the propagation of diatoms in the water, the production of algal blooms can be suppressed in culture ponds or enclosed waters, etc. As a result, the deterioration of the water quality of the culture ponds can be suppressed, and the aquatic organisms of the culture target can be improved ( For example, the survival rate of crustaceans, shellfish, or fish such as shrimps. Furthermore, aquatic organisms (such as crustaceans, shellfish, or fish such as shrimps) that use diatoms as bait grow well.

In addition, in the material for cultivation of the present invention, even if the calcium silicate contained in the material is dissolved in water, the insoluble calcium carbonate contained in the material still remains, so the particle size retention is excellent. Therefore, the above-mentioned material does not disintegrate for a long time (for example, 30 days) and can maintain its particle size (the size of the granule). As a result, the consolidation of the substrate can be prevented, the air permeability and water permeability of the substrate can be improved, and the The bottom substance becomes hypoxic. Furthermore, the remaining calcium carbonate can be used as a calcium supply source for aquatic organisms (for example, crustaceans such as shrimps, shellfish, or fish). In addition, the "bottom substance" in this manual refers to the surface layer of the bottom in fresh water, brackish water or sea water.

[The form of implementing the invention]

The material for aquaculture of the present invention is composed of porous hardened granular bodies. The granular system contains calcium silicate hydrate and unreacted calcareous raw material, which is a reaction product of silicic acid raw material and lime raw material, and calcium carbonate The content rate is 0.1 to 12.0% by mass. The silicic acid raw material referred to here refers to the raw material used to form the silicic acid component (SiO ₂ ) that constitutes calcium silicate hydrate. Examples of silicic acid raw materials include silica, silica sand, diatomaceous earth, and the like. As a silicic acid raw material, based on the viewpoint of enhancing the reaction with the lime raw material, the powder form is usually used. Lime-based raw materials refer to the raw materials used to form calcareous (CaO) that constitute calcium silicate hydrate. Examples of calcareous raw materials can include virgin lime (CaO), slaked lime (Ca(OH) ₂ ), cement and the like. In addition, cement is also a silicic acid raw material. As a calcareous raw material, those in powder or granular form are usually used. Calcium silicate hydrate refers to CaO-SiO ₂ -H ₂ O series compounds (for example, tobermorite known as the main component of autoclaved lightweight aerated concrete). Examples of combinations of silicic acid-based raw materials and lime-based raw materials include (a) the silicic acid-based raw material is silica or silica sand, and the lime-based raw material is a combination of quicklime and cement, and (b) the silicic acid-based raw material is silica or silicon Sand and diatomaceous earth, and the lime-based raw material is a combination of quicklime and cement, (c) the silicic acid-based raw material is silica or silica sand, and the lime-based raw material is a combination of quicklime, slaked lime and cement, etc.

Examples of calcium silicate hydrates include tobermorite, xonotlite, CSH gel, orthorhomite, schonite, quansite, wollastonite, and the like. Tobermorite refers to crystalline calcium silicate hydrate, which has Ca ₅ ･(Si ₆ O ₁₈ H ₂ )･4H ₂ O (plate-like form), Ca ₅ ･(Si ₆ O ₁₈ H ₂ )( Plate-like form), Ca ₅ ･(Si ₆ O ₁₈ H ₂ )･8H ₂ O (fibrous form), etc. Xonotlite refers to crystalline calcium silicate hydrate, which has a chemical composition such as _{Ca 6} ･(Si ₆ O ₁₇ )･(OH) _{2 (fibrous form).}

CSH gel refers to a chemical composition with αCaO･βSiO ₂ ･γH ₂ O (but α/β=0.7～2.3, γ/β=1.2～2.7). Specific examples thereof include calcium silicate hydrate having a 3CaO · 2SiO ₂ · 3H ₂ O chemical composition. Orthorhomite refers to those with chemical composition such as _{Ca 4} (SiO ₃ ) ₃ (OH) _2. Chernolite refers to those with a chemical composition such as _{(NaCa 2} )Ca ₁₄ (Si ₂₃ Al)O ₆₀ (OH) ₈ ･ 14H _{2 O.} The hydrotalcite refers to a chemical composition such as _{Ca 2} SiO ₃ (OH) _2. Wollastonite refers to a _{chemical composition of CaO･SiO 2} (fibrous or columnar form). Among them, from the viewpoint of ease of manufacture and economy, tobermorite is preferable.

Unreacted calcareous raw material refers to the raw materials used to form the calcareous (CaO) that constitute calcium silicate hydrate, which have not reacted with the silicic acid raw material and have not formed the constituent components of calcium silicate hydrate but remain. The unreacted calcareous raw material is usually in the form of calcium hydroxide (Ca(OH) ₂ ), which is the product of the hydration reaction of quicklime, and exists in the porous hardened body.

The content of calcium carbonate in the culture material (granules of the porous hardened body) of the present invention is preferably 0.1-12.0% by mass, more preferably, from the viewpoint of improving the balance between particle size retention and the supply amount of silicic acid 0.5-11.0% by mass, still more preferably 1.0-10.0% by mass, still more preferably 2.0-9.0% by mass, still more preferably 3.0-8.5% by mass, still more preferably 4.0-8.2% by mass, particularly preferably 5.0～8.0% by mass. If the calcium carbonate content is 0.1% by mass or more, the amount of calcium (calcium carbonate remaining in the bottom) taken by aquatic organisms (especially crustaceans or shellfish) will increase, which can further enhance the growth or survival rate of aquatic organisms. If the calcium carbonate content is 12.0% by mass or less, the amount of calcium silicate contained in the culture material can be relatively increased, the amount of silicic acid supplied to the water can be increased, and the diatoms in the water can be further promoted Reproduction.

The culture material (granules of the porous hardened body) of the present invention may also be porous carbonated granules obtained by carbonating a reaction product of a silicic acid raw material and a calcareous raw material. The ratio of calcium silicate hydrate in the solid phase of the reaction product (porous hardened body) of the silicic acid raw material and the lime raw material before carbonation treatment is based on the fact that more silicic acid is used when the aquaculture material of the present invention is used. From the viewpoint of quantitatively supplying to water, it is preferably 40% by mass or more, more preferably 50% by mass or more, and particularly preferably 60% by mass or more. As a silicic acid raw material, use more than one selected from silica, silica sand and diatomaceous earth; as a calcareous raw material, use more than one selected from quicklime, slaked lime and cement, when compared to the silicic raw material When the amount of the calcareous raw material meets the preferable range (0.1-12.0% by mass) of the calcium carbonate content in the porous carbonated granules described later, the silicon in the solid phase of the porous hardened body before carbonation treatment The ratio of calcium acid hydrate is 50% by mass or more. "Carbonation" refers to the formation of calcium carbonate by the reaction of unreacted calcareous raw material (usually calcium hydroxide) contained in the porous hardened body with carbon dioxide (usually carbon dioxide gas).

The culture material (granules of the porous hardened body) of the present invention is porous. The term "porous" here is the same as autoclaved lightweight aerated concrete (ALC), which means that it is foamed by a foaming agent during manufacture to make pores exist in the granular body (hardened body). The porosity of the culture material (porous hardened granules) of the present invention is based on increasing the degree of carbonation during manufacture, and increasing the amount of silicic acid supplied to the water during use, and at the same time ensuring sufficient materials for culture From the viewpoint of strength (for example, compressive strength), it is preferably from 50 to 80% by volume, more preferably from 55 to 75% by volume, and particularly preferably from 60 to 70% by volume. The porosity referred to here refers to the total ratio of the volume of the internal voids in the entire volume of the area surrounded by the outer surface of the granular body of the porous hardened body constituting the culture material of the present invention.

Since the culture material of the present invention is porous, the amount of silicic acid eluted from the culture material can be further increased, and the propagation of diatoms can be further promoted. In addition, since the culture material of the present invention is porous, the air existing in the porous part (internal voids) of the culture material is transported in the bottom material, which can further increase the solubility of the water existing in the bottom material. The amount of oxygen. In addition, the water permeability or air permeability of the substrate can be further improved.

The particle size of the culture material of the present invention is preferably 0.1-15 mm, more preferably 0.3-10 mm, still more preferably 0.5-8 mm, particularly preferably 0.5-5 mm. If the particle size is 0.1 mm or more, the energy required for granulation (for example, crushing or cutting) during the production of aquaculture material can be further reduced, and the consolidation of the substrate can be further suppressed. If the particle size is 15 mm or less, the amount of silicic acid supplied to the water can be further increased. Regarding the particle size distribution of the material for aquaculture of the present invention, the proportion of porous carbonated particles having the above-mentioned preferred particle size (for example 0.5-5 mm) is preferably 50% by mass or more (preferably 60% by mass or more, more preferably 70% by mass or more). In addition, the "particle size" in this manual refers to the size of the sieve hole size of the corresponding sieve. For example, the particle size below 1.0mm means that it can pass through a sieve with a sieve opening of 1.0mm.

Next, the manufacturing method of the breeding material of the present invention will be described. An example of the method for producing a culture material of the present invention includes the following steps: a slurry preparation step, which uses silicic acid raw materials, lime raw materials, foaming agents, and water as raw materials to prepare a slurry; and a hardening step, which The obtained slurry is matured, foamed and hardened to obtain a porous hardened body; the hydrothermal reaction step is to hydrothermally react the obtained porous hardened body to obtain a hydrothermally reacted porous hardened body ; And the step of granulation and carbonation, which uses the porous hardened body after the hydrothermal reaction to obtain the material for breeding. Here, the slurry preparation step, the hardening step, and the hydrothermal reaction step, in addition to comparing the amount of lime-based raw materials relative to silicic acid-based raw materials, and the amount of lime-based raw materials in the general manufacturing method of autoclaved lightweight aerated concrete (ALC) Other than setting it to excess, it is the same as these steps in the general manufacturing method of autoclaved lightweight aerated concrete (ALC). In addition, in the general manufacturing method of autoclaved lightweight aerated concrete (porosity: about 80% by volume), the amount of silicic acid raw material relative to the amount of lime raw material is set to be excessive. Therefore, the solid phase (approximately 20% by volume) of autoclaved lightweight aerated concrete is composed of 13-16% by volume tobermorite and 4-7% by volume of unreacted silicic acid.

The slurry preparation step is, for example, by using silica (as other silicic acid raw materials, silica sand, diatomaceous earth, etc.), cement, quicklime (as other lime raw materials, or slaked lime, etc.), foaming agent ( For example, aluminum powder or surfactant) and water are mixed. As a reaction accelerator that can be blended arbitrarily, dihydrate gypsum can also be used. The amount of each raw material (especially the amount of calcareous raw material), only needs to consider the calcium hydroxide in the porous hardened body after the hydrothermal reaction obtained in the hydrothermal reaction step (after the carbonation treatment in the granulation and carbonation step) The target ratio of those forming calcium carbonate may be appropriately determined. In addition, in this step, based on the viewpoint of adjusting the content rate (further increase) of calcium carbonate in the cultivation material, calcium carbonate may also be used. In addition, industrial calcium carbonate can be used for calcium carbonate, or calcium carbonate-containing substances such as natural limestone can be used.

The curing step is, for example, by pouring the slurry obtained in the slurry preparation step into the mold frame, and then performing 4 to 10 in an environment of normal temperature (for example, 15 to 35°C) and high humidity (for example, relative humidity of 95 to 99%) After hours of aging, it is then aged for 6 to 12 hours in an environment of high temperature (for example, 75 to 85°C) and high humidity (for example, relative humidity of 95 to 99%), and finally demolded to obtain a porous hardened body To proceed. The internal dimensions of the mold frame are not particularly limited, and are, for example, 5 to 40 cm (length) × 5 to 15 cm (width) × 5 to 15 cm (height).

The hydrothermal reaction step is performed, for example, by performing autoclave aging (high-temperature and high-pressure steam aging) on the porous hardened body using an autoclave device. The autoclave aging temperature is preferably 160 to 210°C, more preferably 170 to 200°C, and particularly preferably 180 to 190°C. The autoclave aging pressure is preferably 0.9 MPa to 1.2 MPa (9 to 12 atmospheres), more preferably 1.0 MPa to 1.1 MPa (10 to 11 atmospheres). The aging time of autoclave aging (the time for maintaining the above-mentioned preferred temperature) is preferably 3 to 10 hours, more preferably 4 to 9 hours, more preferably 5 to 8 hours, particularly preferably 5.5 to 7 hours.

The granulation and carbonation step can be by (a) granulating the porous hardened body after the hydrothermal reaction to obtain a porous plasmid, and then carbonating the porous plasmid to obtain a material for breeding. Or (b) Carbonating the porous hardened body after the hydrothermal reaction to obtain a porous carbonated hardened body, then granulate the porous hardened carbonated body to obtain a material for breeding. get on. Examples of the granulation method (granulation treatment method) include pulverization, cutting, and the like. Examples of the method of carbonation (carbonation treatment method) include a method of placing a porous particle body or a porous hardened body in a carbon dioxide atmosphere (including the case where it is placed in the atmosphere). At this time, the concentration of carbon dioxide gas is preferably 1 vol% or more, more preferably 3 vol% or more, still more preferably 4 vol% or more, particularly preferably 5 vol% or more from the viewpoint of further promoting carbonation. In addition, the concentration of carbon dioxide is preferably 90% by volume or less, more preferably 70% by volume or less, still more preferably 50% by volume or less, still more preferably 30% by volume or less from the viewpoint of preventing excessive increase in cost, etc. It is more preferably 20% by volume or less, particularly preferably 10% by volume or less.

The time of carbonation (for example, the time for placing the porous plasmid, etc. in a carbon dioxide environment) is dependent on the size (particle size or size) of the porous plasmid or porous hardened body, or the target ratio of calcium carbonate in the culture material Depending on the size, it is preferably 3 hours or more, more preferably 4 hours or more, and particularly preferably 5 hours or more. From the viewpoint of the efficiency of carbonation treatment, the upper limit of the time is preferably 15 hours, more preferably 12 hours, and particularly preferably 10 hours. The carbonation treatment may be carried out in an autoclave device for carrying out the hydrothermal reaction, or it may be carried out using an apparatus other than the autoclave device for carrying out the hydrothermal reaction. Other devices than the autoclave device may include a carbonation treatment device with a high-concentration carbon dioxide gas environment. It is also possible not to use an autoclave device or a carbonation treatment device, but to place the porous particles or porous hardened bodies before the carbonation treatment in the atmosphere (air; in a gas containing 0.04% by volume of carbon dioxide). Carbonation treatment.

Other examples of the manufacturing method of the aquaculture material of the present invention may include a method including the following steps: a slurry preparation step, which uses silicic acid raw materials, lime raw materials, calcium carbonate, foaming agent and water as raw materials to prepare the slurry; The hardening step is to mature the obtained slurry, foaming and hardening to obtain a porous hardened body; the hydrothermal reaction step is to hydrothermally react the obtained porous hardened body to obtain a hydrothermally reacted product A porous hardened body; and a granulation step, which is a step of granulating the porous hardened body after the hydrothermal reaction to obtain a material for cultivation. Regarding the slurry preparation step, the hardening step, and the hydrothermal reaction step, in addition to using calcium carbonate in the slurry preparation step, and considering the content of the target calcium carbonate in the aquaculture material, the amount of calcium carbonate is appropriately set. The steps are the same. In addition, the granulation method in the granulation step is the same as the granulation method (granulation treatment method) in the granulation and carbonation step described above.

The examples of the culture water used for the culture material of the present invention are not particularly limited, and may be any of freshwater, brackish water and seawater. The aquatic organisms include crustaceans, shellfish, and fish that can be cultured in aquaculture water. Among them, aquatic organisms that use diatoms as bait (such as crustaceans such as shrimp) are preferred. The calcium carbonate contained in the culture material of the present invention is difficult to dissolve in water, so even if calcium silicate hydrate is dissolved in water, calcium carbonate will still remain. Therefore, the material for aquaculture of the present invention can maintain its particle size (the size of the granules) without disintegrating, and as a result, it can prevent the consolidation of the substrate, and can improve the air permeability or water permeability of the substrate, and can prevent the substrate from becoming insufficient. Oxygen state. In addition, the calcium carbonate remaining in the bottom is taken up by aquatic organisms. Calcium can be ingested by aquatic organisms to obtain effects such as improving the strength of the crustacean of juvenile shrimp or the bone of juvenile fish. [Example]

Hereinafter, the present invention will be explained in detail based on examples, but the present invention is not limited to these examples. [Materials used] (1) The proportion of quicklime with a particle size of 2mm or less: 90% by mass or more. The content of CaO: 95% by mass (2) The silica powder is pulverized by a mill with a size of 53-150μm Percentage of particles within the range: 90% by mass or more SiO ₂ content: 98% by mass (3) Diatomaceous earth SiO ₂ content: 82% by mass CaO content: 1% by mass (4) Normal porter Blue Cement (manufactured by Pacific Cement Co., Ltd.) CaO content rate: 63.5 mass% SiO ₂ content rate: 21.5 mass% (5) Aluminum powder (manufactured by High Purity Chemical Co., Ltd.) (6) Calcium carbonate powder (manufactured by Kanto Chemical Co., Ltd.)

[Manufacturing of powder raw material a and evaluation of calcium silicate-containing material a using powder raw material a] Silica powder, ordinary Portland cement and quicklime are mixed with silica powder, ordinary Portland cement and quicklime in 100% by mass of the powder raw materials, and silica powder, ordinary Portland cement and quicklime are used. The blending ratios of each of the content ratios of 65% by mass, 25% by mass, and 10% by mass were mixed to obtain powder raw material a.

The obtained powder raw material a is used to prepare a calcium silicate-containing material a, and powder X-ray diffraction is performed on the material a. Specifically, after adding 40 parts by mass of water to 100 parts by mass of "powder raw material a" and kneading, 0.01 parts by mass of aluminum powder was further added and kneaded to obtain a slurry. The obtained slurry was poured into a mold frame having an internal size of 10×10×10 cm, and cured for 6 hours under an environment of 30° C. and a relative humidity of 98%. Next, after aging for 8 hours in an environment of 80°C and a relative humidity of 98%, the porous hardened body in the mold frame is removed from the mold. The demolded porous hardened body was subjected to hydrothermal aging (hydrothermal reaction) in an autoclave at 180°C and 1.0 MPa (10 atmospheres) for 6 hours. After the hydrothermal aging was completed, the porous hardened body was taken out from the autoclave and dried at 105°C for 24 hours. After drying, the porous hardened body is pulverized to obtain a calcium silicate-containing material a. According to the result of identification of calcium silicate-containing material a based on powder X-ray diffraction, it was confirmed that tobermorite was formed. The formation of calcium hydroxide and calcium carbonate has not been confirmed.

[Manufacture of powder raw material b and evaluation of calcium silicate-containing material b using powder raw material b] In addition to using diatomaceous earth, silica powder, ordinary Portland cement and quicklime, in 100% by mass of the powder raw materials made by mixing these materials, diatomaceous earth, silica powder, ordinary Portland cement and The content of quicklime is 35% by mass, 25% by mass, 25% by mass, and 15% by mass, respectively. The powder raw material b is mixed with the blending ratio of 35% by mass, 25% by mass, and 15% by mass. The preparation method of material a is the same as that of material b containing calcium silicate. According to the result of the identification of the calcium silicate-containing material b based on powder X-ray diffraction, it was confirmed that tobermorite was formed. The formation of calcium hydroxide and calcium carbonate has not been confirmed.

[Examples 1 to 6] The content rate of each raw material (quicklime, silica powder, cement) in 100% by mass of the raw material mixture of powder raw material a and quicklime mixed with powder raw material a and quicklime is each as shown in Table 1 Mix to obtain a raw material mixture. Specifically, the amount of quicklime is 0% by mass (Comparative Example 1), 0.5% by mass (Example 1), 1.0% by mass per 100% by mass of the total amount of powdered raw material a (containing quicklime) and quicklime % (Example 2), 2.0% by mass (Example 3), 4.0% by mass (Example 4), 6.0% by mass (Example 5), 8.0% by mass (Example 6) Quicklime mix. In addition, the content rate of quicklime in the obtained raw material mixture (indicated as "raw material for aquaculture" in Table 1) contains quicklime derived from the powder raw material a.

After adding 40 parts by mass of water to 100 parts by mass of the obtained raw material mixture and kneading, 0.01 parts by mass of aluminum powder was further added and kneaded to obtain a slurry. The obtained slurry was poured into a mold frame having an internal size of 10×10×10 cm, and cured for 6 hours under an environment of 30° C. and a relative humidity of 98%. Next, after aging for 8 hours in an environment of 80°C and a relative humidity of 98%, the porous hardened body in the mold frame is removed from the mold. The demolded porous hardened body was subjected to hydrothermal aging (hydrothermal reaction) in an autoclave at 180°C and 1.0 MPa (10 atmospheres) for 6 hours. After the hydrothermal aging is completed, the hardened body is taken out from the autoclave and dried at 105°C for 24 hours. The obtained porous hardening system contains calcium silicate (tobermorite) and calcium hydroxide. After drying, the porous hardened body was cut into cut pieces into cubes of approximately 2×2×2 cm. The resulting cube-shaped porous hardened body was allowed to stand for 6 hours in a closed container with a carbon dioxide concentration of 5% by volume, and then carbonated to obtain a cube containing calcium silicate (tobermorite) and calcium carbonate Shaped porous carbonated hardened body.

[Measurement of calcium carbonate content in porous hardened carbonated bodies] The cube-shaped porous hardened carbonated body was pulverized, and then sieved using a sieve with a mesh opening of 1 mm. The powder of the aquaculture material with a particle size of 1 mm or less that can pass through the sieve is heated at 650°C, and then further heated at 900°C. Calculate the content of calcium carbonate in the cultivation material from the mass reduction of the powder when heated at 650-900°C (due to the desorption of carbon dioxide). The results are shown in Table 1.

[Measurement of the amount of water-soluble silicic acid eluted from the porous hardened carbonated body] The cube-shaped porous hardened carbonated body was pulverized, and then sieved using a sieve with 1 mm opening. Add 1 g of porous hardened carbonated powder with a particle size of 1 mm or less that can pass through a sieve to 1 liter of distilled water, and then, while shaking at 70 rpm, the distilled water is replaced every 24 hours. Use ICP emission spectrometer to measure the concentration of Si dissolved in the replaced distilled water, and calculate _{the daily dissolution amount of water-soluble silicic acid (SiO 2} ) (mg/L/day) from the time of adding the powder of aquaculture material to 7 days. . The results are shown in Table 2.

[Evaluation of particle size retention (relative evaluation with respect to the comparative example)] After pulverizing the cube-shaped porous carbonated hardened body, a sieve with a mesh opening of 5 mm and a sieve with a mesh opening of 0.5 mm are used to obtain a culture material with a particle size of 0.5 to 5 mm. 50 g of the culture material was put into a polyethylene bag with water permeability (the culture material cannot pass through, but the water can pass through), and set on the bottom of the shrimp culture pond. After 30 days from the time of installation, the bag was recovered from the culture pond, the soil or diatoms attached to the bag were removed with water, and then dried at 105°C. After drying, the culture materials are taken out from the bag, and screened using a sieve with a sieve opening of 0.5 mm. Secondly, the quality of the aquaculture material passed through the sieve and the quality of the aquaculture material remaining on the sieve were measured separately. From the obtained mass, use the following formula (1) to calculate the proportion of the aquaculture material remaining on the sieve. The proportion of the culture material remaining on the sieve (%) = (the quality of the culture material remaining on the sieve) × 100/(the quality of the culture material remaining on the sieve + the quality of the culture material passing the sieve) ···(1)

Next, the ratio of the cultivation material remaining on the sieve after 30 days in Comparative Example 1 (described later) was calculated in the same manner as described above. Based on the ratio of the culture material remaining on the sieve in Comparative Example 1 (100), the ratio of the culture material remaining on the sieve in each of the examples (Examples 1 to 6) is calculated using the following formula (2) , Expressed as a numerical value. (The relative evaluation value of each example relative to the comparative example 1)=(the ratio of the culture material remaining on the sieve in each example)×100/(the ratio of the culture material remaining on the sieve in the comparative example 1 ) ···(2) In addition, the larger the relative evaluation value of the example relative to the comparative example 1, the better the particle size retention. The results are shown in Table 2.

[Evaluation of particle size retention (absolute evaluation)] After pulverizing the cube-shaped porous carbonated hardened body, a sieve with a mesh opening of 5 mm and a sieve with a mesh opening of 0.5 mm are used to obtain a culture material with a particle size of 0.5 to 5 mm. After taking an image of 50 g of the culture material, put the culture material into a polyethylene bag with water permeability (the material cannot pass through, but the water can pass through), and set it on the bottom of the shrimp culture pond. After 30 days from the time of installation, the bag was recovered from the culture pond, the soil or diatoms attached to the bag were removed with water, and then dried at 105°C. After drying, take out the breeding material from the bag, and take an image of the breeding material.

The images of the culture materials installed in front of the culture ponds and the images of the culture materials recovered from the culture ponds are analyzed using the "area measurement software" provided by the "Vector" (online software distribution website). Use the following formula (3) to calculate the ratio (%) of the flat area of the cultivation material before installation and the flat area of the cultivation material after recovery (after 30 days) by the image analysis. Percentage of flat area (%) = (flat area of breeding material after 30 days)×100/(flat area of breeding material before installation) (3) In addition, the larger the ratio (%) of the flat area, the better the particle size retention.

[Comparative Example 1] Except that the porous hardened body after the hydrothermal reaction was cut into each block into a cube of about 2×2×2 cm, without carbonation treatment, and drying at 105°C for 3 hours, the same as in Example 1 In the same way, a porous hardened body was obtained. With respect to the obtained porous hardened body, the measurement of the calcium carbonate content rate, etc. were performed in the same manner as in Example 1. In addition, the porous hardened body was used in the same manner as in Example 1 to obtain a culture material, and the particle size retention was evaluated.

[Examples 7-13] In addition to using powder raw material b instead of powder raw material a, and powder raw material b and quicklime, each raw material (quicklime, silica powder, The content of diatomaceous earth and cement) was mixed so that the content of each was shown in Table 1. Except that the raw material mixture was obtained, the porous carbonated hardened body was obtained in the same manner as in Example 1. Specifically, the amount of quicklime is 0% by mass (Comparative Example 2), 0.5% by mass (Example 7), 1.0% by mass per 100% by mass of the total amount of powder raw material b (containing quicklime) and quicklime % (Example 8), 3.0% by mass (Example 9), 5.0% by mass (Example 10), 7.0% by mass (Example 11), 9.0% by mass (Example 12), 10.0% by mass (Example 13 ) The powder raw material b is mixed with quicklime. In addition, the content of quicklime in the obtained raw material mixture contains quicklime derived from the powder raw material b. With respect to the obtained porous hardened carbonated body, the measurement of the calcium carbonate content rate and the like were performed in the same manner as in Example 1. In addition, the porous carbonated hardened body was used in the same manner as in Example 1 to obtain a culture material, and the particle size retention was evaluated.

[Comparative Example 2] A porous hardened body was obtained in the same manner as in Comparative Example 1, except that the powder raw material b was used instead of the powder raw material a. With respect to the obtained porous hardened body, the measurement of the calcium carbonate content rate, etc. were performed in the same manner as in Example 1. In addition, the porous hardened body was used in the same manner as in Example 1 to obtain a culture material, and the particle size retention was evaluated.

[Examples 14-16] The content rate of each raw material (quicklime, silica powder, cement, calcium carbonate powder) in 100% by mass of the raw material mixture made by mixing powder raw material a, quicklime and calcium carbonate powder becomes the method shown in Table 1 They are mixed to obtain a raw material mixture. Specifically, the amount of calcium carbonate powder is each 100% by mass of a raw material mixture made by mixing powder raw material a (containing quicklime, silica powder and ordinary Portland cement), quicklime and calcium carbonate powder. The powder raw material a, quicklime, and calcium carbonate powder were mixed in a manner of 1.0% by mass (Example 14), 2.0% by mass (Example 15), and 4.0% by mass (Example 16). In addition, the amount of quicklime is the same as that of calcium carbonate powder. The reason for adding quicklime is to make the amount of lime-based raw materials relative to silicic-acid-based raw materials excessive compared to the amount of lime-based raw materials in the general manufacturing method of autoclaved lightweight aerated concrete (ALC). In addition, the content of quicklime in the obtained raw material mixture includes quicklime derived from the powder raw material a.

Using the obtained raw material mixture, a porous hardened body was obtained in the same manner as in Example 1. The porous hardening system contains calcium silicate (tobermorite) and calcium hydroxide. Using this porous hardened body, the carbonation treatment was carried out in the same manner as in Example 1 to obtain cubic porous carbonated granules (material for cultivation) containing calcium silicate (tobermorite) and calcium carbonate . With respect to the obtained material for cultivation, the measurement of the calcium carbonate content rate and the like were performed in the same manner as in Example 1.

[Examples 17-19] The content of each raw material (quick lime, silica powder, cement, calcium carbonate powder) in 100% by mass of the raw material mixture obtained by mixing powder raw material a and calcium carbonate powder is mixed so that the content rate is shown in Table 1. , And get the raw material mixture. Specifically, the amount of calcium carbonate powder is 2.0% for every 100% by mass of a raw material mixture made by mixing powder raw material a (containing quicklime, silica powder, and ordinary Portland cement) and calcium carbonate powder. % (Example 17), 5.0% by mass (Example 18), and 10.0% by mass (Example 19), the powder raw material a and calcium carbonate powder were mixed. In addition, the content of quicklime in the obtained raw material mixture contains quicklime derived from the powder raw material a. The granular body of the porous hardened body (material for cultivation) was obtained in the same manner as in Example 1, except that the obtained porous hardened body was cut and the carbonation treatment was not performed. In addition, the above-mentioned porous hardening system contains calcium silicate (tobermorite) and calcium hydroxide. With respect to the obtained material for cultivation, the measurement of the calcium carbonate content rate and the like were performed in the same manner as in Example 1. The above results are shown in Table 2.

It can be seen from Table 2 that according to the culture material of the present invention (Examples 1-19), after adding 1 g of the culture material to 1 liter of distilled water, even after 7 days, the daily dissolution of water-soluble silicic acid is still maintained Above 0.8mg/liter. In addition, from the comparison between Examples 1 to 6 and Comparative Example 1, the comparison between Examples 7 to 13 and Comparative Example 2, the comparison between Examples 14 to 16, and the comparison between Examples 17 to 19, it can be seen that the calcium carbonate content rate is higher. Smaller (conversely speaking, the greater the content of calcium silicate), the greater the tendency for the daily dissolution of water-soluble silicic acid. In addition, with regard to the evaluation of particle size retention (relative evaluation and absolute evaluation), comparing Examples 1 to 19 and Comparative Examples 1 to 2, it can be seen that the culture material of the present invention (Examples 1 to 19) is better than calcium carbonate. The content rate of 0% by mass for aquaculture materials (Comparative Examples 1 to 2), the particle size retention is more excellent. In particular, it can be seen that Examples 3 to 5 (calcium carbonate content: 2.4 to 8.0% by mass), Examples 9 to 11 (calcium carbonate content: 2.9 to 7.8% by mass), and Examples 14 to 16 (calcium carbonate content: Rate: 2.1 to 9.5% by mass) and Examples 18 to 19 (content rate of calcium carbonate: 4.3 to 9.1% by mass) have particularly excellent particle size retention.

Claims (6)

A material for aquaculture, which is characterized by being composed of porous hardened granules, the granular system comprising calcium silicate hydrate and unreacted calcareous raw material of the silicic acid raw material and the reaction product of the calcareous raw material, and calcium carbonate The content rate is 0.1 to 12.0% by mass. Such as the cultivation material of claim 1, wherein the above cultivation material contains granules with a particle size of 0.5-5 mm in a proportion of 50% by mass or more. The material for cultivation of claim 1 or 2, wherein the porous hardened body granular system is a porous carbonated granular body obtained by carbonating a reaction product of a silicic acid raw material and a calcareous raw material. A method for manufacturing aquaculture materials, which is a method for manufacturing materials for aquaculture such as claim 1 or 2, characterized by including: A slurry preparation step, which uses the above-mentioned silicic acid raw material, the above-mentioned lime-based raw material, calcium carbonate, foaming agent and water as raw materials to prepare a slurry; The hardening step is to mature the above-mentioned slurry, make it foam and harden, to obtain a porous hardened body; The hydrothermal reaction step involves hydrothermally reacting the porous hardened body to obtain a porous hardened body after the hydrothermal reaction; and The granulation step is to granulate the porous hardened body after the hydrothermal reaction to obtain the material for cultivation. A method for manufacturing aquaculture materials, which is a method for manufacturing the aquaculture materials as in Claim 3, and is characterized in that it includes: A slurry preparation step, which uses the above-mentioned silicic acid raw material, the above-mentioned lime-based raw material, foaming agent and water as raw materials to prepare a slurry; The hardening step is to mature the above-mentioned slurry, make it foam and harden, to obtain a porous hardened body; The hydrothermal reaction step involves hydrothermally reacting the porous hardened body to obtain a porous hardened body after the hydrothermal reaction; and The granulation and carbonation step uses the porous hardened body after the hydrothermal reaction to obtain the above-mentioned material for cultivation, and, The granulation and carbonation step is a method of (a) granulating the porous hardened body to obtain a porous plasmid, and then carbonating the porous plasmid to obtain the material for cultivation, or (b) After carbonizing the porous hardened body to obtain a porous carbonated hardened body, any one of the methods for obtaining the above-mentioned cultivation material by granulating the porous carbonated hardened body. According to claim 4 or 5, the method for manufacturing a culture material, wherein the silicic acid raw material includes one or more selected from silica, silica sand and diatomaceous earth, and the calcareous raw material includes quicklime, slaked lime and cement One or more of them, and the above-mentioned foaming agent system contains aluminum powder.