Solidified materials and underwater structures

Abstract

To provide a solidifying material that can secure sufficient strength and suppress load on an underwater environment and an ecosystem as much as possible, and to provide an underwater structure.SOLUTION: A solidifying material includes: at least one of the distillation lees and sake lees; and a joint material including a magnesium oxide and a magnesium chloride.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a solidifying material and an underwater structure.

Background Art

[0002] In order to improve the functions of underwater structures such as fish reefs or algal reefs installed in the sea, the size, shape, surface shape, and chemical properties of the material of the underwater structure have been improved. When an underwater structure contains an amino acid or the like, the effect of attracting aquatic organisms is improved. In addition, it is expected that the amino acids contained in the underwater structure will promote the adhesion and growth of bacteria and microalgae, which serve as food for aquatic organisms, to the underwater structure.

[0003] Patent Document 1 discloses an underwater environment regeneration structure made of a concrete block kneaded with an amino acid that exhibits an adhesion and growth effect on algae.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The underwater environment regeneration structure disclosed in Patent Document 1 is made of a concrete block. Concrete remains in a strongly alkaline state in water for a long period of time. For this reason, there are concerns about the impact on the underwater environment and ecosystem. In general, a cement solidified body may have delayed hardening when containing organic substances, and may not harden depending on the formulation. For this reason, sufficient strength may not be obtained.

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to provide a solidifying material and an underwater structure that can ensure sufficient strength and suppress the load on the underwater environment and ecosystem as much as possible.

Means for Solving the Problems

[0007] The solidifying material according to the first aspect of the present invention comprises at least one of distillers' grains and sake lees, and a binder containing magnesium oxide and magnesium chloride. Sodium bicarbonate, and and is provided with

[0008] The solidifying material according to the first aspect of the present invention may further be provided with aggregate. This may be the case.

[0009] In this case, the solidifying material according to the first aspect of the present invention comprises the distillers' grains, and the distillers' grains may be sweet potato shochu lees or awamori lees. This may be the case.

[0010] Also, the solidifying material according to the first aspect of the present invention comprises the distillers' grains, and the distillers' grains may be fermented. This may be the case.

[0011] The underwater structure according to the second aspect of the present invention contains the solidifying material according to the first aspect of the present invention.

Advantages of the Invention

[0012] According to the present invention, sufficient strength can be ensured, and the load on the underwater environment and ecosystem can be suppressed as much as possible.

Brief Description of the Drawings

[0013]

Figure 1

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Mode for Carrying Out the Invention

[0014] Embodiments according to the present invention will be described with reference to the drawings. Note that the present invention is not limited by the following embodiments and drawings.

[0015] (Embodiment) The solidified material according to the present embodiment includes at least one of distillation lees and sake lees, and a binder. The distillation lees is a residue remaining after fermenting a raw material with yeast to produce brewed liquor and distilling the liquor and recovering the distillate. The raw material is not particularly limited and includes grains, livestock milk, rice, wheat, barley, wheat, rye, corn, grain, sugar beet, potato, sugar cane, sweet potato (Ipomoea batatas), brown sugar, buckwheat, chestnut, molasses, grape, banana, and cassava, etc. The distillation lees is preferably sweet potato shochu lees produced in the production of sweet potato shochu (sweet potato spirit) using sweet potato as a raw material or awamori lees produced in the production of awamori using rice as a raw material. The sake lees is a white solid remaining after pressing in the production of Japanese sake.

[0016] The distillation residue may be a fermented distillation residue. In particular, since about 95% of the sweet potato shochu residue is water and its properties are likely to change, the distillation residue fermented with lactic acid bacteria may be used to improve the storability. The fermentation treatment is performed by a known method. For example, a mixture obtained by mixing the distillation residue and lactic acid bacteria may be adjusted to a temperature that is the optimum temperature for the lactic acid bacteria.

[0017] The bonding material contains at least magnesium oxide and magnesium chloride. As the bonding material, a commercially available magnesia-based mortar containing magnesium oxide and magnesium chloride may be used.

[0018] The solidification material according to this embodiment may further include an aggregate. As the aggregate, a known one used in the solidification material can be used. The aggregate is, for example, sand, fine sand, gravel, stone, crushed stone, and the like.

[0019] The solidification material according to this embodiment may include an admixture. The admixture is appropriately blended for the purpose of improving the ease of mixing and placing, improving the strength, or accelerating the curing. Examples of the admixture include inorganic salts such as sodium carbonate, potassium carbonate, sodium bicarbonate, and potassium bicarbonate, AE agents, water reducers, AE water reducers, high-performance AE water reducers, fluidizing agents, and curing accelerators.

[0020] A method for manufacturing a structure using the solidifying material according to this embodiment will be described. First, at least one of distillers' grains and sake lees, a binder, and an aggregate are mixed. In this mixing step, it is preferable to mix distillers' grains or sake lees into the kneaded binder, and then add the aggregate and further mix. The mixing ratio of at least one of distillers' grains and sake lees, the binder, and the aggregate is appropriately set. For example, taking magnesium oxide as 1 part by mass, the distillers' grains or sake lees are 0.20 to 0.50 parts by mass, 0.25 to 0.48 parts by mass, 0.28 to 0.46 parts by mass, or 0.30 to 0.45 parts by mass, preferably 0.32 to 0.43 parts by mass. The mixing ratio of magnesium chloride is 0.3 to 0.7 parts by mass, 0.4 to 0.6 parts by mass, or 0.5 to 0.6 parts by mass with magnesium oxide as 1 part by mass. The mixing ratio of the aggregate is 0.5 to 3.0 parts by mass, 0.8 to 2.0 parts by mass, or 1.0 to 1.8 parts by mass with magnesium oxide as 1 part by mass. In the mixing step, water may be added to the mixture in consideration of the fluidity of the mixture containing at least one of distillers' grains and sake lees, the binder, and the aggregate.

[0021] After the mixing step, the mixture is cured. In the curing step, the mixture may be left standing for several days or several weeks. In order to make the structure obtained by curing the mixture into a desired shape, in the curing step, the mixture poured into a mold may be cured. Through the curing step, a structure is obtained.

[0022] The structure manufactured with the solidifying material according to this embodiment has strength exceeding general civil engineering standards as shown in the following examples. Also, since the solidifying material is weakly alkaline and has a pH almost equal to that of seawater, it does not impose a large load on the underwater environment, particularly the marine environment and ecosystem. Also, as shown in the following examples, the fine algae adhering to the structure manufactured with the solidifying material placed in water are more numerous compared to cement mortar not containing distillers' grains and sake lees.

[0023] Distillation residues and sake lees are often treated as industrial waste, and their treatment has been an issue. Since the solidification material according to this embodiment utilizes at least one of distillation residues and sake lees, it contributes to the effective utilization of resources. In addition, since distillation residues and sake lees contain amino acids and the like, it is considered that marine organisms gather and seaweeds are likely to grow.

[0024] The solidification material according to this embodiment may be provided with aggregates. By doing so, a solidification material provided with aggregates according to the use of the structure manufactured from the solidification material is provided, enhancing convenience. In the case where the solidification material according to this embodiment does not include aggregates, the aggregates selected by the user according to the use of the structure manufactured from the solidification material may be mixed in the mixing step.

[0025] In addition, the solidification material according to this embodiment may be provided in a mode in which at least one of distillation residues and sake lees and the binder are separately packaged. Further, when the solidification material includes aggregates, the solidification material may be provided in a mode in which the aggregates are separately packaged from at least one of distillation residues and sake lees and the binder. Also, in other embodiments, the use of at least one of distillation residues and sake lees as a solidification material is provided.

[0026] In another embodiment, an underwater structure including the above solidification material is provided. The underwater structure can be manufactured by the method for manufacturing a structure using the above solidification material. The underwater structure can be used in seawater and fresh water and is installed in the ocean, rivers, lakes, ponds, etc. Specifically, the underwater structure is a breakwater, a wave-dissipating breakwater, a greening plate, an artificial fish reef, an artificial seaweed reef, etc. Note that the above solidification material is applicable not only to underwater structures but also to onshore structures.

[0027] For example, the algal reef as the underwater structure described above is suitable for seaweed cultivation and the like. Examples of seaweeds include kombu, hiziki, mozuku, wakame, asparagus seaweed, tengusa, green laver, blue-green laver, and nori. In other embodiments, a method for cultivating seaweed is provided, which includes a step of attaching seaweed seeds to an underwater structure containing the above solidifying material, and a step of immersing the underwater structure in water, particularly in the sea.

[0028] The present invention will be described in more detail by the following examples, but the present invention is not limited by the examples.

Example

[0029] (Evaluation of Strength of Solidifying Material) As distillers' grains, distillation residues generated in the production of awamori, barley shochu, sweet potato shochu, and brown sugar shochu were used. Also, a 15% aqueous solution of sake lees was used. As binders, magnesium oxide (manufactured by Maehata Sangyo Co., Ltd., hereinafter referred to as "MgO") and magnesium chloride (manufactured by Naikai Salt Industry Co., Ltd., hereinafter referred to as "MgCl 2 ") were used. As aggregate, fine sand (produced in Hirakaga, Higashikata Town, Sarufutsu-gun, Hokkaido) was used.

[0030] After kneading the binder alone, distillers' grains or sake lees were mixed, and fine sand was added and further kneaded to obtain samples. In some examples, admixtures were mixed during the kneading of the binder alone. The pH of the kneaded samples was measured using litmus test paper. The samples were placed in a cylindrical mold (bottom diameter 50 mm, height 100 mm). For sufficient curing, they were cured for more than one week and demolded to obtain test specimens (Examples 1 to 13). Table 1 shows the formulations (mass ratios) and pH values of each test specimen.

[0031] Compression tests were performed on the test specimens in accordance with JIS A 1108, and the compression strengths at 1 day, 7 days, 14 days, and 28 days of age were measured. For the measurement of the compression strength, a testing machine (manufactured by Tokyo Kokei Seisakusho) conforming to 6 of JIS B 7733 was used.

[0032]

Table 1

[0033] (Result) The pH values of Examples 1 to 3 were weakly alkaline in the range of 8 to 8.5. The results of the compressive strength tests of Examples 1 to 3 are shown in Fig. 1. In all the examples using shochu lees, the compressive strength, which is the target strength and the design standard strength of general civil engineering concrete products at 14 days of age, was 24 N / mm 2 was obtained.

[0034] The pH values of Examples 4 to 6 were weakly alkaline in the range of 8 to 8.5. The results of the compressive strength tests of Examples 4 to 6 are shown in Fig. 2. The target strength was obtained in all the examples using wheat distillers' grains.

[0035] The pH values of Examples 7 to 9 were weakly alkaline in the range of 8 to 8.25. The results of the compressive strength tests of Examples 7 to 9 are shown in Fig. 3. The target strength was obtained in all the examples using sweet potato shochu lees.

[0036] The pH values of Examples 10 to 12 were weakly alkaline in the range of 7.75 to 8.5. The results of the compressive strength tests of Examples 10 to 12 are shown in Fig. 4. The target strength was obtained in all the examples using brown sugar distillers' grains.

[0037] The pH value of Example 13 was weakly alkaline at 8.25. The results of the compressive strength test of Example 13 are shown in Fig. 5. The target strength was obtained in the example using sake lees.

[0038] MgO and MgCl 2 When each distillers' grains or sake lees is mixed with a binder containing, regardless of the types of distilled liquor and Japanese sake and even when changing the amount of lees, the compressive strength N / mm at which demolding is possible at 1 day of age is 2 above, and the compressive strength above the general civil engineering standard strength of 24 N / mm at 7 days of age was 2 confirmed. All the examples were weakly alkaline in the range of 7.75 to 8.5 and had a pH almost equivalent to that of seawater. It is known that cement-based solidified bodies do not solidify at this pH. Thus, MgO and MgCl 2It has been shown that when the main material is used and the lees of main distilled spirits or Japanese sake are mixed, a solidifying material having a weakly alkaline and practically usable strength can be obtained.

[0039] (Evaluation 1 of the adhesion characteristics of microalgae to the solidifying material) Using a cylindrical mold (bottom diameter 11 mm, height 20 mm), specimens (Example 14 and Comparative Examples 1 to 3) were prepared in the same manner as in Examples 1 to 13 at the mass ratios shown in Table 2. As the aggregate, fine sand (produced in Hirakaga, Hidaka-cho, Sarufutsu-gun, Hokkaido) with a coarse grain ratio of 2.72 (JIS A 1102) and a passing rate of 0.075 of 0.3% (JIS A 1103) was used. As the Portland cement, ordinary Portland cement (manufactured by Taiheiyo Cement Corporation) was used. Since about 95% of the sweet potato shochu lees is water and it is strongly acidic and its properties change easily, fermented shochu lees treated with lactic acid bacteria was used. In the fermentation treatment, the shochu lees at 90°C or higher immediately after distillation was cooled to 45°C or lower over one day and night, and then 1.7 kg of lactic acid bacteria was added per 100 tons of shochu lees. As the lactic acid bacteria, CyMaster·AC (Lactococcus lactis and Lactobacillus paracasei) manufactured by Snow Brand Seed Co., Ltd. was used.

[0040] The pH of the fermented shochu lees is 3.8 and the components are as shown in Table 3. In Example 14, when mixing the fermented shochu lees, if all the moisture was made the fermented shochu lees, the fluidity decreased and it could not be filled into the mold without gaps, so water was mixed for preparation.

[0041]

Table 2

[0042]

Table 3

[0043] The test specimens were embedded in vinyl chloride flat plates (15 mm thick). To prevent the microalgae adhering to the surface of the test specimens from being preyed on by fish and the like, the test specimens were covered with a cage net and installed in the sea. The cage net was suspended from a floating pier so that the vinyl chloride flat plate embedded with the test specimens would be horizontal. Since the floating pier rises and falls with the change in the tide level, the depth of the test specimens was constant at about 50 cm. The seawater temperature during the experimental period was measured at 10-minute intervals using a small memory water temperature meter (manufactured by JFE Advantech Co., Ltd., COMPACT-TD ATD-HR) attached to the cage net. In the summer experiment, 10 test specimens were collected each time, a total of 7 times, 3 days after immersing the test specimens in seawater, and 1 week to 6 weeks later. In the winter experiment, 10 test specimens were collected each time, a total of 3 times, 1 week to 3 weeks after immersing the test specimens in seawater. The collected test specimens were immersed in an N,N-dimethylformamide solution, and the concentration of the photosynthetic pigment chlorophyll a was measured using a fluorometer (manufactured by Turner Designs, TD-700), and the adhesion density, which is the amount of chlorophyll a adhered per unit area, was calculated.

[0044] (Results) There were fine irregularities on the surfaces of Comparative Example 1 and Comparative Example 2 produced, but the surfaces of Comparative Example 3 and Example 14 were shiny and smooth. In the previously conducted summer experiment, the test specimens were used as they were, but in the subsequent winter experiment, the surfaces were scraped with sandpaper to make the surfaces of the test specimens as identical as possible.

[0045] The seawater temperature during the period when the specimens were immersed in seawater varied in the range of 26°C to 31°C in the summer experiment and 17°C to 21°C in the winter experiment. The results of the summer test are shown in Fig. 6. In the summer experiment, the attachment density increased significantly from 1 week to 2 weeks after immersion and tended to gradually decrease from 3 weeks to 6 weeks after immersion. In Comparative Example 1, the attachment density reached its maximum after 2 weeks, and in Comparative Examples 2, 3, and Example 14, it reached its maximum after 3 weeks. During the immersion period except after 3 days and 5 weeks, the attachment density of Example 14 was the highest, and the attachment density of Example 14 was significantly higher than that of Example 1 after 1 week, 3 weeks, and 6 weeks (Steel's method, p < 0.01). The results of the winter test are shown in Fig. 7. In the winter experiment, the attachment density of Example 14 was the highest from 1 week to 3 weeks after immersion, and the attachment density was significantly higher than that of Example 1 after 1 week and 2 weeks of immersion (Steel's method, p < 0.01).

[0046] From the above, it was shown that the amount of microalgae attachment was larger in the magnesia-based mortar mixed with fermented shochu lees than in the cement mortar.

[0047] (Evaluation of the attachment characteristics of microalgae to solidification materials 2) Using a cylindrical mold (bottom diameter 11 mm, height 20 mm), specimens (Examples 15, 16, and Comparative Examples 4, 5) were prepared in the same manner as in Examples 1 to 13 at the mass ratios shown in Table 4. Similar to Example 14, a cage net for holding the specimens was installed in the sea. The seawater temperature during the experiment was measured at 1-hour intervals using a small memory water thermometer (manufactured by BASICO Trading Co., Ltd., HOBO MX Pendant Logger) attached to the cage net.

[0048] Every week after immersion, 10 specimens were collected and immersed in about 5.0 g of N,N-dimethylformamide solution. The concentration of the photosynthetic pigment chlorophyll a extracted by the N,N-dimethylformamide solution was measured with a fluorometer to determine the attachment density.

[0049]

Table 4

[0050] (Result) During the experimental period, the seawater temperature changed in the range of 17.7 to 23.2 °C. The test results of Examples 15 and 16 and Comparative Examples 4 and 5 are shown in Fig. 8. The attachment density of chlorophyll a tended to increase after 2 weeks of immersion in all cases, and Comparative Example 5 and Example 16 continued to increase until 6 weeks after immersion. The attachment density of chlorophyll a reached its maximum at 5 weeks after immersion in Comparative Example 4 and at 6 weeks after immersion in the others, and the highest value was 39.8 mg / m 2 for Example 15.

[0051] The attachment density of chlorophyll a in Example 15 was significantly higher than that in Comparative Example 4. The attachment density of chlorophyll a in Example 15 was significantly higher than that in Comparative Example 4 4 weeks after immersion, significantly lower 5 weeks after immersion, but there was no significant difference 6 weeks after immersion.

[0052] From the above, it was shown that the amount of microalgae attachment also tended to increase in the magnesia-based mortar mixed with sake lees and black sugar shochu distillation lees.

[0053] (Test Example 1: Seaweed growth block test) With the formulation shown in Table 5 (1 m 3 ), in the same manner as in Examples 1 to 13, seaweed growth blocks were produced using concrete or sake lees-mixed magnesia-based solids (concrete as Comparative Example 6 and sake lees-mixed magnesia-based solids as Example 17).

[0054]

Table 5

[0055] After attaching seaweed seeds to the seaweed growth blocks in November 2019, they were installed on the seabed off Hirara, Higashi Village, Kunigami District, Okinawa Prefecture. In April 2020, after about 5 months had passed, the seaweed growing on the block surface was harvested and the weight of the seaweed was measured.

[0056] (Result) The weight of the seaweed in Comparative Example 6 was 1100 g / m2 whereas in Example 17, it was 1920 g / m 2 . By blending awamori lees, the weight of mozuku became about 1.7 times more.

[0057] (Test Example 2: Mozuku Plate Test) Using the formulation shown in Table 6 below (1 m 3 ), a mozuku-growing plate having a plurality of columnar convex portions on the plate was produced in the same manner as in Examples 1 to 13 using a mold (concrete was used as Comparative Example 7, awamori lees-mixed concrete was used as Comparative Example 8, and awamori lees-mixed magnesia-based solid was used as Example 18).

[0058]

Table 6

[0059] In March 2020, plates with mozuku seeds attached and plates without attached seeds were installed on the seabed off Hirara Coast, Higashi Village, Kunigami District, Okinawa Prefecture. In June 2020, about three months later, the mozuku that had grown on the plate surface was harvested, and the weight of the mozuku was measured.

[0060] (Results) When no mozuku seeds were attached, it was 480 g / m in Comparative Example 7 2 and 1992 g / m in Comparative Example 8 2 , whereas in Example 18, it was 2448 g / m 2 . When mozuku seeds were attached, it was 1836 g / m in Comparative Example 7 2 and 3684 g / m in Comparative Example 8 2 , whereas in Example 18, it was 4824 g / m 2 .

[0061]

Table 7

[0062] As described above, it was shown that the amount of seaweed growth in the concrete containing sake lees increased by 2.0 to 4.2 times compared to the concrete without sake lees. It was revealed that the amount of seaweed growth in the magnesia-based solidified body containing sake lees increased by 2.6 to 5.1 times compared to the concrete without sake lees.

[0063] The above-described embodiments are for explaining the present invention and do not limit the scope of the present invention. That is, the scope of the present invention is indicated not by the embodiments but by the claims. And various modifications made within the scope of the claims and within the scope of the meaning of the invention equivalent thereto are regarded as being within the scope of the present invention.

Industrial Applicability

[0064] The present invention is suitable for manufacturing underwater structures, particularly artificial fish reefs, seaweed beds, and the like.

Claims

1. At least one of distiller's lees and sake lees, A bonding material including magnesium oxide and magnesium chloride; Sodium bicarbonate, A solidified material comprising:

2. Further comprising aggregate. The solidified material of claim 1 .

3. The distiller's grains are provided, The distillation lees are sweet potato shochu lees or awamori lees.

3. The solidified material according to claim 1 or 2.

4. The distiller's grains are provided, The distillers grains are fermented. A solidified material according to any one of claims 1 to 3.

5. The solidification material according to any one of claims 1 to 4, Underwater structures.

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