JP5216708B2 - Nutrient dispersion in the aquatic environment - Google Patents

Description

  The present invention relates to a nutrient dispersion for promoting the propagation of marine organisms in a water environment such as the ocean.

  In recent years, the reduction of marine resources has been regarded as a problem. Therefore, in order to protect and nurture marine resources and preserve living environment in coastal waters, structures such as fish reefs, algae reefs, and submerged dikes are installed.

As one of the above structures, one made of steel slag is known. Steelmaking slag has a high water purification effect among various slags produced in the steel manufacturing process. As its action, the increase in pH due to the elution of CaO in the slag reduces the generation of hydrogen sulfide by suppressing the activity of sulfate-reducing bacteria, and the hydrogen sulfide in water is reduced by CaO and Fe ₂ O ₃ in the slag. It can be fixed.

  As a submerged dike using such a steelmaking slag, for example, Patent Document 1 discloses a submerged dike constructed by stacking steelmaking slag of a predetermined size (specifically, 60 mass% or more of a steelmaking slag lump having a particle size of 100 mm or more). , A steel slag lump with a grain size of 30-300mm piled up at a ratio of 95% by mass or more, and the piled dike covered with a runoff prevention net (mesh opening 50-200mm) was proposed. Has been. The steel slag having a predetermined size is accommodated in a container having an open top surface and openings on the side and bottom surfaces (total area ratio of the openings is 20% or more), and a plurality of the steel slag are arranged on the bottom of the water, or It has also been proposed to arrange in a stacked manner.

  The thing of the said patent document 1 regulates the clearance gap between slag chunks by prescribing | sizing a slag lump size, and makes it easy to wash away the deposit in a clearance gap by a tidal current etc. As a result, the adhesion and accumulation of organic floating mud on the submerged dike constituent material is suppressed, and the original water quality purification action of steelmaking slag is effectively exhibited.

  Patent Document 2 proposes a container in which a fertilizer material containing steel slag (steel slag or blast furnace slag) is accommodated in a container having an upper surface opened or a hole formed in the upper surface. The fertilizer components that are leached from fertilizer materials are used to breed and nurture marine life.

  Here, the ratio (D / d) of the maximum dimension d of the open part on the container upper surface or the hole and the depth D from the container upper surface to the surface of the fertilizer material is defined to be 0.2 or more. This regulation increases the depth D so as to suppress excessive erosion from the fertilizer material and to maintain the fertilizer effect over a long period of time.

JP 2005-256497 A JP 2007-330254 A

  By the way, when it is the structure which dissipates various components from the upper direction like the said prior art, there exists a possibility that the opening part of an upper surface may be closed by deposition of sludge etc. which sinks from the reverse. The confirmation of this closure is difficult because it is underwater, and the removal of deposits is costly. If this state is left as it is, the water purification effect of the steelmaking slag and the fertilization effect of the fertilizer material are not exhibited at all, and it becomes a mere industrial waste accumulation place.

  In this regard, the submerged dike of Patent Document 1 adjusts the gap size according to the slag lump size as described above so that the deposits are easily washed away, but the effect is not guaranteed to be permanent. Moreover, in the container containing fertilizer material of the said patent document 2, it cannot be said that the accumulation of sludge etc. is considered in the first place.

  Therefore, the present invention has been made paying attention to the above-mentioned circumstances, and its purpose is to minimize the covering of the fertilizer material by deposits such as sludge as much as possible, and to effectively use the original effect of the fertilizer material. Another object of the present invention is to provide a nutrient dissipative that can be continuously exerted.

  The nutrient dispersoid according to the present invention is a nutrient dispersoid that is installed in water and disperses the nutrients into the water, and a fertilizing material containing divalent iron is accommodated in the closed container, and the closed container However, it is characterized in that two or more holes are provided in the side wall.

  Although sludge etc. falls and accumulates exclusively from the top, in the present invention, the container that stores the fertilizer material is a closed container having a hole in the side wall, and the upper surface is closed. Does not enter the container. Therefore, the fertilizer material is hardly covered with deposits such as sludge, and the elution of nutrients from the fertilizer material is sustained.

  And the eluted nutrient diffuses to the outside through two or more holes on the side wall of the container, attracts marine organisms to the surroundings, and promotes their reproduction.

  Here, the reason why the number of holes on the side wall of the container is not one is that if there is only one hole, the hole becomes either an inflow or an outflow, and water enters and exits the inside and outside of the container. However, the elution from the fertilizer material itself does not progress, and the eluted nutrients are difficult to go out of the container. If there are two or more holes, one will serve as a water inflow hole and the other will serve as a water outflow hole corresponding to the direction and strength of the tidal current that changes from time to time, and water will smoothly enter and exit the inside and outside of the container. . Therefore, the elution nutrients present in the container are easily diffused out of the container.

  As an arrangement mode of the two or more holes, a position which is a side wall of the container and is separated from each other is preferable, and the arrangement of the holes can be variously modified. Specifically, for example, when two holes are arranged, it is most preferable that the holes are provided at positions facing each other on the side wall of the container. This is because water easily flows from one hole to the other hole in the container.

  In this case, the two holes are preferably arranged so as to form a central angle of 60 to 180 ° with respect to the center of the container (the center of the horizontal cross section of the container and the center in the depth direction of the container). When three or more holes are provided, the above two holes are not limited to adjacent holes, and the center angle between distant holes may be 60 to 180 °.

  That is, the “center angle” refers to an angle formed by a straight line extending from the center point in the horizontal section of the container to the two holes when two holes are provided at the same height on the side wall of the container. . When two holes with different heights are provided in the vertical direction of the container side wall, the holes extend from the center point of the vertical section of the container so as to include the center point of the horizontal section of the container. An angle formed by a straight line. Further, when two holes are arranged obliquely on the side wall of the container, it means an angle formed by a straight line extending from the center of the container to the two holes.

  For example, when a hole is provided in the center of each side wall in a container having a square horizontal section, the center of the hole a provided in a certain side wall A and the hole b provided in the side wall B opposite to the side wall A The angle is 180 °. In this case, the central angle between the hole c provided in the side wall C adjacent to the side wall A and the hole a is 90 °. In addition, for example, in a container having a rectangular horizontal cross section as shown in FIG. 2, there are various holes having a central angle of 60 to 180 ° with respect to each hole. Two or more holes may be provided only on one side wall of the polygonal container as long as the central angle can be arranged at 60 ° or more.

  More preferably, the two holes are arranged so that the central angle is 90 to 180 °.

  Moreover, since this invention is the structure which provided the hole in the closed container, the water of the external environment (outside a container) does not directly hit the accommodated fertilizer material, and it can prevent the rapid fall of the nutrient of a fertilizer material. And by adjusting the number and size of the holes in consideration of the installed ocean current and water depth, the nutrients (especially iron ions) eluted from the fertilizer material can be released gradually, thus maintaining the fertilizer effect over a long period of time. can do.

  By the way, when fertilizing material is housed in a net made of net, most of the fertilizing material is directly exposed to the ocean current, etc., so the nutrient elution rate of the fertilizing material cannot be adjusted and may decrease rapidly. . For this reason, it becomes difficult to maintain nutrient release for a long period of time.

  As for the size of the hole of the container, it is preferable that the longest diameter is 50 mm or less and the shortest diameter is 10 mm or more. There are various shapes such as a circle, an ellipse, and a square as the shape of the hole. For example, in the case of an ellipse, the longest diameter is the length of the major axis, and the shortest diameter is the length of the minor axis. say. For example, in the case of a rectangle, the longest diameter refers to the length of the diagonal line, and the shortest diameter refers to the length of the short side.

  Current and tidal currents act on the nutrient dispersoids placed in the water, and the water inside is exchanged through the holes in the container. However, if the shortest diameter of the holes is less than 10 mm, it is too small (long holes In this case, it is too thin), and the inflow and outflow of water into the container cannot be performed smoothly.

  On the other hand, the exchange speed of water in the container is suppressed by setting the longest diameter of the hole to 50 mm or less. This is because if the exchange rate is too fast, the nutrient content of the fertilized material will decrease drastically, resulting in wasteful dissipation. Further, by suppressing the exchange rate, the nutrients eluted from the fertilizer material can be increased to a certain extent in the container and released to the outside. For example, the concentration of eluted Fe (II) can be increased to a certain extent in the container, stabilized with citric acid, and gradually released out of the container.

  Although the exchange speed is affected by nearby ocean currents and tidal currents, it is preferable that the water in the container is changed about once a day. For example, when the container capacity is 70 liters, the hole diameter may be adjusted so that the amount of liquid flowing into and out of the container (exchange amount) is 70 liters / day.

  Furthermore, it is preferable that the nutrient dispersoid of the present invention is obtained by adding measures for preventing the fertilization material from flowing out in parallel for the following reason. The first countermeasure against outflow is a structure in which a fiber body is accommodated in an empty space inside the closed container. In this case, the fiber body includes a fiber bundle, a string, a fabric (woven fabric, knitted fabric, non-woven fabric), cotton, and the like. Can be mentioned. Since the nutrient dispersoid of the present invention is installed in the sea for a long period of time, from the viewpoint of sustaining the effect, use one made of a material that is not corroded by seawater such as corrosion-resistant stainless steel, polyester, polyamide, carbon fiber. From the viewpoint of serving also as an iron source, it is also possible to use one made of iron or steel.

  If the fertilizer material originally contains a lot of small particle size, or breaks when immersed in seawater, and if the fertilizer material becomes smaller than the original due to the elution of nutrients in the seawater, the fertilizer material is exposed to the outside through the hole of the closed container. There is a concern that it will leak out. This is because, depending on the material and composition of the fertilizer material, there are ones that gradually become smaller due to the elution of nutrients, and ones that become porous even if the size of the outer shape is maintained.

  In this regard, if the fiber body is accommodated in the empty space as described above, the fertilizer material is attached or held on the fiber body, and the outflow to the outside is prevented.

  Moreover, as an effect other than the above by accommodating a fibrous body, it can be mentioned that the amount of water entering and exiting the container and the inflow rate can be alleviated by the presence of the fibrous body. Therefore, when installing the nutrient dispersion in the water, the amount of water entering and exiting the container is adjusted by adjusting the capacity of the fiber body at the site according to the current tides, ocean currents, etc. You can also

  A second countermeasure against outflow is a configuration in which the fertilizing material is accommodated in the closed container in a state of being accommodated in an openable / closable mesh bag or mesh container. By taking this second countermeasure, the fertilizer material is retained inside the mesh bag (or mesh container), and outflow to the outside of the container can be prevented by the same mechanism as the first countermeasure. In addition, it is desirable that the mesh hole of the net bag (or net container) be sufficiently smaller than the fertilizer material. As for net bags (or net containers), they are made up of fine wires, threads, strings, wires, etc. using natural fibers, synthetic fibers, metal fibers, inorganic fibers, etc., as well as a box shape in which punched metal plates are assembled. Can also be used. In the case of a net-made container, it may have a shape without a lid with an open top. Further, since the nutrient dispersoid of the present invention is installed in the sea for a long period of time, it is more desirable to use a material composed of a material that is not corroded by seawater such as corrosion-resistant stainless steel, polyester, polyamide, carbon fiber, From the viewpoint of serving also as an iron source, it is also possible to use a steel or steel made thick.

  In addition, it is also recommended that the two measures to prevent outflow be performed in parallel, that is, to store the net bag and store it inside the closed container, and store the fibrous body in the empty space generated at that time. Embodiment.

  Moreover, it is preferable that at least one of the upper surface part, the bottom surface part, and the side wall of the closed container is openable and closable. If it can be freely opened and closed in this way, it becomes possible to replace or add a new fertilizer material by a diver when the nutrients in the fertilizer material are completely eluted.

  Examples of the openable / closable configuration include a lid type in which the lid is detachable and a door type that is opened / closed with one side connected by a hinge or the like.

  Moreover, it can also serve as an iron source by forming all or part of the closed container in the nutrient diffuser with an iron-based material. In particular, when a ferrous material-made closed container is in contact with a carbon source such as charcoal among fertilized materials, iron is easily ionized and eluted from the contacted portion. Therefore, in the case of this configuration, in addition to the above-described effect of maintaining sustained release by a closed container having two or more holes, the effect of promoting the elution of iron ions from the portion in contact with charcoal on the inner surface of the closed container is also demonstrated. Can do. In this case, it is preferable that the wall of the closed container is sufficiently thick so that a through-hole due to elution during the submergence period does not occur.

  Whether the fertilized material in the present invention is (1) a solidified material containing steel slag and / or granular iron as the divalent iron source and forming a chelate complex with divalent iron ions and charcoal. (2) It is preferably a solidified product containing steel slag and / or granular iron as the divalent iron source and containing charcoal. In the case of (2) above, an organic substance that forms a chelate complex with a divalent iron ion may be housed in a closed container as another solidified body.

  Divalent iron is a component effective for the propagation of aquatic organisms, and steel slag and granular iron are sources of divalent iron.

  Steel slag also serves as an aggregate when solidified with cement or the like. Examples of the solidifying agent include cement and various binders, but are not limited thereto. Moreover, you may use things other than steel slag as an aggregate.

  Examples of steel slag include blast furnace slag and steelmaking slag. The blast furnace slag is separated and recovered together with the ash of the auxiliary material when producing pig iron. Steelmaking slag is slag generated in the steelmaking process.

  Carbon is a material for promoting the elution of iron ions from the iron source (steel slag or granular iron) by utilizing the difference in ionization tendency from iron. As this carbon source, charcoal (charcoal, bamboo charcoal, etc.) is suitable as described above.

  Examples of the organic substance forming the chelate complex include divalent to polyvalent polycarboxylic acids. As the polycarboxylic acid, citric acid, fulvic acid or salts thereof are preferable. These polycarboxylic acids can stabilize divalent iron ions having a high fertilizing effect as chelate forms among the generated iron ions.

  Moreover, about the magnitude | size of a fertilizer material, it is preferable that a longest diameter is 10 mm or more and 200 mm or less. As described above, ocean currents and tidal currents act on fertilizer material in the container through the hole, but with small fertilizer materials of less than 10 mm, there is a concern that even a slow current will easily move and flow out of the hole of the container. Because there is. On the other hand, if it exceeds 200 mm, the surface area becomes smaller than the volume, so that the elution of nutrients is not sufficient for the size.

  Furthermore, it is preferable that a fertilizer material is larger than the longest diameter of the hole of the said container. Thereby, the outflow from the hole of a fertilizer material can be prevented.

  Examples of the mesh bag include a wire mesh cube container. By constructing one of the surfaces of the wire mesh container so as to be openable and closable, the contained fertilizing material can be exchanged and added.

  According to the nutrient dispersion according to the present invention, the fertilizer material is hardly covered with deposits such as sludge, and the original effect of the fertilizer material can be effectively and continuously exhibited.

It is a perspective view which shows the nutrient dissipative body which concerns on Embodiment 1 of this invention. It is a perspective view which shows the nutrient dissipative body which concerns on Embodiment 2 of this invention. It is a perspective view which shows the nutrient dissipative body which concerns on Embodiment 3 of this invention.

  Hereinafter, the nutrient dispersoid according to the present invention will be described in detail with reference to the drawings showing examples. However, the present invention is not limited to the illustrated examples, and can be adapted to the purpose described above and below. It is also possible to carry out by appropriately changing the range, and all of them are included in the technical scope of the present invention.

<Embodiment 1>
FIG. 1 is a perspective view showing a nutrient dispersion 10 according to Embodiment 1 of the present invention.

  The nutrient dispersion 10 is a closed container 11 in which a fertilizer material (not shown) is accommodated. The closed container 11 has a disk-shaped lid 13 detachably attached to a bottomed cylindrical container body 12. The upper end portion of the main body 12 is a flange 12 a, which is overlapped with the peripheral portion 13 a of the lid 13 and fixed by a clamp 15.

  Four circular holes 14 are formed in the peripheral wall (side wall) of the main body 12. The diameter of each hole 14 is 10 mm. These holes 14 form a set of two, and are arranged to face the peripheral wall of the container main body 12. In other words, these four holes 14 are equally arranged so as to have a central angle of 90 °.

  The material of the closed container 11 is steel or plastic. Both the container body 12 and the lid 13 may be made of steel or plastic, or one of them may be made of steel and the other may be made of plastic.

  The fertilizer material is obtained by solidifying granular iron, steelmaking slag, charcoal, and citric acid with cement, and then crushing to about 70 to 100 mm as the longest diameter (solidified product).

  This solidified product is accommodated in a plastic bowl-like container (or a punch made of punching plate), and further contained in a closed container 11 to form a nutrient dispersion 10.

  In use, the nutrient dispersion 10 is installed in the vicinity of a fish reef or a submerged dike installed in the sea area.

  In the sea, nutrients such as divalent iron and phosphorus are eluted from the fertilizer material in the container 11 of the nutrient dispersion 10. Then, the seawater, tidal current, and waves are affected from the lateral direction of the container 11, and the seawater in the container 11 is exchanged when the seawater flows in and out of the hole 14, and the eluted nutrients are released to the outside of the container 11. .

  At this time, since the hole 14 is not so large, the elution nutrient is gradually released, and the release of the nutrient lasts for a long time. And this nutrient can be expected to increase the breeding of marine life.

  Moreover, since the upper surface of the closed container 11 (nutrient dispersion 10) is closed, sludge etc. hardly accumulate in the closed container 11. Therefore, the fertilizer material is not buried in the deposit, and the effect of the fertilizer material can be effectively exhibited. Moreover, since the nutrients are released gradually, the rate of decrease in the nutrients of the fertilizer material is gradual, and the nutrients can continue to be eluted over a long period of time.

  When no nutrient is left in the fertilizer material, the lid 13 may be removed and a new fertilizer material may be added or replaced in the container 11.

<Embodiment 2>
FIG. 2 is a perspective view showing a nutrient dispersion 20 according to Embodiment 2 of the present invention. In addition, the part which attached | subjected the code | symbol same as FIG. 1 is the same component as the example of FIG.

  The closed container 21 of the nutrient dispersion 20 is formed by attaching a rectangular plate-shaped lid 23 to a container body 22 having a bottomed rectangular tube shape in a detachable manner. And the upper surface opening part of the container main-body part 22 can be closed with the lid | cover 23 now. The lid 23 is fixed by a clamp 15 when attached.

  Two holes 14 are formed in each of the four side walls of the container body 22. That is, the hole 14 is arranged to face the side wall of the container body 22. Other configurations are the same as those in the first embodiment.

  Also in the nutrient dispersion 20 of this Embodiment 2, since the upper surface is closed, the fertilizer material in the container 22 is hardly covered with deposits. Then, since the fertilizer material is not directly exposed to the outside world, nutrients are slowly eluted from the fertilizer material, and the nutrients are gradually released through the holes 14. Therefore, the original effect of the fertilizer material can be exhibited effectively and continuously.

<Embodiment 3>
FIG. 3 is a perspective view showing a nutrient dispersion 30 according to Embodiment 3 of the present invention. In addition, the part which attached | subjected the code | symbol same as FIG. 1 is the same component as the example of FIG.

  In the nutrient solution dispersion 30 of the third embodiment, the lid 13 is attached to the container main body 12 with bolts 35 and nuts 36, and the other configurations are the same as those of the first embodiment.

  Also in the nutrient dispersion 30 of the third embodiment, since the upper surface is closed, the fertilizer material in the container 12 is hardly covered with deposits, and the nutrient from the fertilizer material is gradually released through the holes 14. The Therefore, the original effect of the fertilizer material can be exhibited effectively and continuously.

<Other embodiments>
In the first to third embodiments, the side walls of the closed container are provided with holes, but holes may be provided on the bottom surface.

  In the first to third embodiments, the upper surface lid is configured to be detachable. However, the present invention is not limited to this, and a configuration in which the side wall and the bottom surface portion are detachable may be used.

  In attaching the container body and the lid of the closed container, a fixture such as a wire or a binding band may be used in addition to the clamp 15 and the bolt 35-nut 36 as in the above embodiment.

<Experiment>
As a closed container, a cubic container in which one hole was formed on each of four side walls was used. The dimensions (size) of the container are 200 mm wide × 200 mm wide × 200 mm high. The hole is circular, and the diameter is as shown in Table 1 below.

  A solidified material containing iron is prepared as a fertilizing material (longest diameter: 100 mm), and this is made of a punch made of punching plate having a width of 100 mm, a width of 100 mm, and a height of 150 mm (the hole diameter of this punch is 16 mm in diameter, and the opening ratio is about 15). %). This was accommodated in the said closed container and installed in the flowing water tank. This flowing water tank can set the flow velocity at the same level as the ocean current.

  The flow rate was set to 20 mm / sec., And the exchange amount (inflow / outflow amount) of water in the closed container was calculated from the outflow amount of iron from the closed container.

  Regarding the amount of water exchanged in a closed container, even if the container size is different, if the container shape is similar (same shape with different sizes), and the same hole is provided in the same arrangement, the exchange amount will be It has been found to be constant regardless of size. Considering the ease of handling, the size of the nutrient dispersion (contained fertilizer material in a closed container) is 400mm wide x 400mm wide x 400mm high (with a capacity of about 62 liters). It is preferably about 1500 mm × width 1500 mm × height 1500 mm (with an internal volume of about 3,340 liters). In order to stably release the nutrients from the internal fertilizer material to the outside of the container stably for a long time, it is preferable that the water in the container is changed about once a day. 3,340 liters is desirable.

  As can be seen from Table 1, when the hole size is 70 mm in diameter as in Experiment No. 3, the exchange amount of 6,000 liters per day is equivalent to the state in which the container is almost open. On the other hand, when the hole size is 50 mm or less as in Experiment No. 1 or 2, the exchange amount is 2,500 liters or less per day. Therefore, it can be seen that the pore size is preferably 10 mm to 50 mm from the viewpoint of sustained release of nutrients.

  In addition, following the above experiment, when the same experiment was conducted using a fertilizer material whose longest diameter was gradually reduced from 100 mm to 20 mm (both larger than the pore diameter (diameter 16 mm)), the results were satisfactory. The effect that should have been confirmed.

10, 20, 30 Nutrient dispersion 11, 11 Closed container 13, 23 Lid 14 Hole 15 Clamp 35 Bolt 36 Nut

Claims (6)

In the nutrient solution that is installed in the water and the nutrients are dissolved in the water,
The nutrient dispersoid is made of fertilized material containing divalent iron contained in a closed container,
The enclosure is state, and are not more than one hole is provided in the side wall,
The fertilizer material comprises a steel slag and / or granulated metallic iron as the divalent iron source of organic matter to form the bivalent iron ions and chelate complexes, as well as nutrients, wherein solidified der Rukoto containing charcoal Dispersant.   The nutrient solution according to claim 1, wherein the pores have a longest diameter of 50 mm or less and a shortest diameter of 10 mm or more.   The fiber container is housed together with the fertilizer material in the closed container, or the fertilizer material is housed in an openable / closable mesh bag or mesh container and then accommodated in the closed container. 2. The nutrient dispersoid according to 2.   The nutrient dispersoid according to any one of claims 1 to 3, wherein at least one of an upper surface portion, a bottom surface portion, and a side wall of the closed container is openable and closable. The nutrient dispersoid according to any one of claims 1 to 4, wherein the organic substance forming the chelate complex is a divalent to polyvalent polycarboxylic acid. The nutrient dispersion according to claim 5, wherein the fertilizer material is larger than the longest diameter of the hole.

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