JPS5851730B2 - Porous conglomerate-type fish reef and manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a porous agglomerated soft rock type fish reef made of modified blast furnace slag and a method for producing the same.

As is well known, various types of fish reefs have been devised and actually installed for the purpose of protecting and breeding fish in coastal waters.

However, various conventional concrete reefs require time and effort to manufacture, and the cost of transporting them to a predetermined location at sea and dropping them into the sea is high, making them unsuitable for large-scale reef construction.

In addition, various types of steel reefs are expensive, the cost of installing them on the seabed is high, and the growth of seaweed tends to be lower than that of concrete reefs, which is also a problem in large scale. It is not suitable for constructing fish reefs.

One of the objects of the present invention is to provide a fish reef suitable for making large-scale fish reef construction possible, and another object is to provide a fish reef that can be manufactured at a low cost.
Yet another object is to provide a reef with extremely low transportation and reef construction costs, and yet another object is to provide an inexpensive method of reef construction.

It is well known that blast furnace slag is generally generated in large quantities as a by-product of pig iron production, and has traditionally been used as roadbed material and landfill material.

Recently, active use of blast furnace slag has been considered for other purposes, but its use as concrete aggregate has limitations in terms of strength and chemical composition, making it difficult to use in civil engineering. Even if it is used for various purposes, its use as a building material will not progress unless its physical properties are improved.

In other words, blast furnace slag is a useful resource that has different uses.

It is well known that research is being conducted on the use of blast furnace slag as a fish reef, and examples of laboratory-scale or extremely small-scale underwater experiments have been reported.

However, these are experimental examples using blast furnace slag as it is, and even though it is recognized that it is effective in attracting fish and growing fish, it is difficult to use blast furnace slag as it is as a fish reef, and moreover, as a large-scale fish reef. Improvements are considered to be necessary in the following points.

Sonohitsu is a component of blast furnace slag, and as shown in one example in Table 1, the rather high content of S is considered unfavorable for the purpose.

Although Fe and Mn in Table 1 often exist in the form of oxides, they are shown in the form of content (% by weight) in the table.

Further, S exists as a single substance or in the form of oxides or other compounds, and these are also shown in terms of content (% by weight).

Now, when considering the effects on fish and other marine life, it is desirable to minimize the amount of substances leached into the sea, apart from harmless substances such as Ca.

As a result of experiments, the reformed blast furnace slag according to the present invention contains significantly less eluate in water, and is considered to have almost no problems as a fish reef.

To give an example, the modified blast furnace slag according to the present invention was continuously immersed in water for 6 days, and the transmittance of the eluate was measured using a spectrophotometer. Even when compared with the absorbance of slag of 0.56 (max), the advantages of reformed blast furnace slag are clear.

Next, the blast furnace slag is crushed into lumps and granules for transportation reasons, but at this time, a large amount of powdery slag is generated, and if this is dumped into the sea at the same time as the lumps and slags, the powdery slag will spread into the sea. It is considered undesirable.

Thirdly, when blast furnace slag is affected by undersea currents on the seabed, it is easy to get lost due to its light specific gravity. That is to say.

However, on the other hand, blast furnace slag has the following advantages.

In other words, it is effective for the growth of marine organisms due to its high content of CaO, and because it is porous, it promotes the reproduction of microorganisms, and it has significant advantages for the growth of seaweed.

In view of the above, the present inventor has devised a fish reef and a method for producing the same which solves the above-mentioned problems and improves the advantages. The porous agglomerated soft rock type fish reef and the agglomerated blast furnace slag obtained by bonding together the aggregates of the modified aggregated slag with cement are washed with a dilute mineral acid solution or immersed in the solution to react. After that, it is heat-treated with a heating device to obtain reformed blast furnace slag, and then, using a stirring device, cement is sprinkled on the lump slag to the extent that the lump slag adheres to each other, and then the lump slag is placed on the work floor. The present invention provides a method for manufacturing a porous agglomerated soft rock type fish reef, which is characterized by mounding it into an arbitrary shape and solidifying it.

In the present invention, lumpy and granular blast furnace slag refers to molten slag discharged from a blast furnace, which is transported to a slag discharge hot water (usually referred to as a slag field) in a slag discharge hot water, and then left to cool naturally. Alternatively, the material is solidified by well-known forced cooling such as water or spray water, or the material is crushed by crushing means such as a crusher after solidification, or the molten slag is crushed by compressed air, pressure water, or a mixture thereof. This refers to slag that has been dispersed into agglomerates, molten slag that has been splashed off with a rotating drum to form agglomerates, or slag that has been modified by mixing additives into molten slag, but the purpose of the present invention is to From the point of view of low cost, which is one of the reasons, it is suitable to solidify by natural cooling or water cooling, and then crush it into agglomerates by suitable crushing means known in the art.

Furthermore, there is no suitable expression for the dimensions of lumpy and granular blast furnace slag since it is originally amorphous, but if it is simulated as a spherical body, the objective can be achieved with a diameter of 5 to 500 ridges.

However, if the diameter is large, it will be difficult to handle in terms of post-process mineral acid treatment and handling, and if the diameter is small, the amount of cement required for adhesion will be large, making it economically disadvantageous.

However, the aforementioned diameters are not limited to these.

In other words, the above-mentioned blast furnace slag usually exists in arbitrary proportions from small diameter to large diameter at the stage of rough crushing, and in the present invention, there is little need to distinguish and use them precisely.

However, from the viewpoints of ease of processing in mineral acid treatment and cement bonding processes, ease of transportation, design of equipment, and product quality, it is preferable that the particle size of the lumped and granular blast furnace slag be uniform, that is, the particle size is 15~ Although the 150mm diameter is easy to handle,
The stricter the particle size regulation, the more expensive the crushing and sieving will be.

Therefore, the particle size range should be designed appropriately depending on conditions such as the desired construction site of the reef, the target fish species, the construction period until completion of the reef, and seabed conditions.

Next, regarding the mineral acid treatment of the present invention, namely pickling, as is well known, in order to expand the use of blast furnace slag as concrete aggregate, blast furnace slag is treated with diluted mineral acid to improve the surface properties. In addition, measures have been taken to prevent the release of highly alkaline leached water by bringing blast furnace slag into contact with carbon dioxide gas or carbonated water.

However, these are not utilized on an industrial scale.

Although the present invention also utilizes the above-mentioned treatment means, an example of a treatment method using dilute sulfuric acid as the most economical treatment means will be described in detail with reference to the drawings.

In FIG. 1, a belt conveyor 1 transports blast furnace slag from a blast furnace slag discharge hot water (not shown) and charges it into a crusher 2.

The crushed blast furnace slag is passed through a sieving process as required and is fed into a cage 5 provided in a processing tank 4 by a conveyor 3.

The treatment tank 4 is filled with dilute sulfuric acid sent from a dilute sulfuric acid supply vibro, and air is blown from the bottom through a compressed air supply pipe 7, so that the treatment tank 4 is mounted on a pedestal 8. The blast furnace slag in cage 5 is washed with dilute sulfuric acid,
Furthermore, chemical reactions occur and the surface properties change.

The important reaction at this time is shown by the following equation (1). CaS + H2So4 = CaS04 + H2S = "(1) The H2S generated at this time is sent to a reaction device (not shown) through the intake pipe 9, and undergoes the chemical changes shown in the following reaction equations (2) to (4). It is regenerated as dilute sulfuric acid.

The regenerated dilute sulfuric acid is returned to the treatment tank 5 via the diluted sulfuric acid feeding vibro.

One of the features of the present invention is that the dilute sulfuric acid necessary for the treatment is obtained from the blast furnace slag itself.

Next, the blast furnace slag that has been treated is transported to the heating device 10 by a transportation means such as a crane (not shown) while being received in the cage 5, and is heated here, thereby fixing the gypsum on the surface of the slag. At the same time, native sulfur compounds are gasified,
In addition, sulfuric acid adhering to the surface of the slag is decomposed.

The gas discharged from the heating device 10 is sent to the above-mentioned reaction device through the exhaust gas pipe 11, and is used for regenerating dilute sulfuric acid.

The blast furnace slag that has gone through this process, that is, the reformed blast furnace slag, is transferred to conveyor 1.
2 into the rotating drum 13 and the cement supply pipe 1
It is mixed with the cement (mortar) sent from 4, and the surface is covered with cement, and then transferred to conveyor 15.
is sent to the work floor 16 and heaped up into an arbitrary shape,
After a certain period of time, it solidifies and becomes a porous conglomerate soft rock reef.

This is divided into arbitrary chunks using a bulldozer or puncher (not shown), transported to a carrier ship, and the carrier vessel then dumps the reefs all at once into a predetermined sea area, making it possible to construct a large fish reef that has never been seen before. Become.

Therefore, the method for producing fish reefs is not limited to the means shown in FIG. Processing is possible even with a furnace type system, and the heating device 10 is not a fixed combustion gas heating system, but a moving bed type, a combustion gas ventilation system such as a dosoiroid sintering equipment, or an electric heating system. It doesn't matter if it's something.

Furthermore, the mixing of the modified blast furnace slag and cement (in the present invention, it is used in the sense of all things commonly abbreviated as cement, such as a mixture of water and cement, a mixture of water, cement, and fine sand) is to the extent that the granules adhere to each other. is sufficient, so
The device is not limited to the rotating drum 13, and may be a stirring tank or a cement mixer truck, and in the present invention, these are collectively referred to as a stirring device.

Next, the work floor may be made of earth, concrete, crushed stone, etc., as long as work equipment such as bulldozers, scrapers, butchers, or cranes with gripping devices can be operated, but from the point of view of workability, it is preferable to use iron plates. A work floor that is laid flat and welded into one piece is more preferred.

Next, in the porous agglomerated fish reef according to the present invention, the agglomerates are bonded to each other with cement, as shown in FIG.
is composed of many.

Furthermore, since the aggregate slag 1T itself has a large number of deaeration holes, it is effective for the adherent growth of seaweed and the reproduction of microscopic sea creatures, as described above.

The size and number of holes 18 will vary greatly depending on the size of the slag, the degree of particle size adjustment, and the degree of cement adhesion, but the greater the amount of cement used, the better the mechanical strength of the reef will be. The amount of cement used should be determined according to the purpose of the reef.

The type of cement to be used next is not particularly limited, but blast furnace cement is the most economically effective.

Since blast furnace cement is mainly made from blast furnace slag turned into water slag, it is not often used in applications where high mechanical strength is required.

In the case of fish reefs, mechanical strength is not required so much, so blast furnace cement is sufficient, and the fact that most of the reef constituent material is blast furnace slag is very economical.

Next, if you want to pile up the lumps and slag sprinkled with cement (mortar) on the work floor into an arbitrary shape, pile up the lumps and slag into a mountain shape as shown in Fig. 3 (19 a > 19 b), and then pile it up as appropriate. It is easier to work if the bulldozer 18 is used to divide the rock into irregularly shaped agglomerated rocks when the rock solidifies.

The mounds are not limited to this, and may be made into independent mounds, or a method may be adopted in which the mounds are put into a simple mold and allowed to solidify, or the heaps can be sorted into heaps using vinyl cloth, etc., to facilitate the division work. It is also possible to adopt the method of

Next, we will explain the advantages of porous conglomerate rock-type fish reefs that have been divided into arbitrary sizes (simply referred to as "main fish reefs").

As mentioned above, this reef can be produced in large quantities at low cost, making it easy to construct huge reefs, and because the reef is angular, it is less likely to be rolled over by seafloor currents, and the reefs are entangled with each other. It is easy to construct a stable fish reef disassembly.

It also has the advantage of being able to transport large quantities using a dedicated transport and laying ship, and that laying and dropping can be done in a short time.

It also has many advantages, as it is porous and has a large surface area, making it effective for protecting fish, and because it has been modified, there is no concern about its impact on the environment.

[Brief explanation of drawings]

FIG. 1 is a flowchart of a process for manufacturing a fish reef according to the present invention, FIG. 2 is an explanatory diagram of the external appearance of a reef according to the present invention, and FIG. 3 is an explanatory diagram of an embodiment of the process for manufacturing a fish reef. 1: Belt conveyor, 2: Crusher, 3: Conveyor, 4: Processing tank, 5: Cage, 6: Dilute sulfuric acid feeding pipe, 1
: Compressed air supply pipe, 8: Frame, 9: Intake pipe, 1
0: heating device, 11: exhaust gas pipe, 12: conveyor,
13: rotating drum, 14: cement supply pipe, 15: conveyor, 16: working floor, 11: lump slag, 18: full dozer, 19 a, 19 b, + mountain range soft granule slag.

Claims (1)

[Scope of Claims] 1. A porous agglomerated soft rock-type fish reef made by bonding together the lumps of modified wind slag obtained by pickling and heat-treating agglomerated blast furnace slag with cement. 2. After washing the lump and granular blast furnace slag with a dilute mineral acid solution or immersing it in the solution to cause a reaction, heat treatment is performed using a heating device to obtain reformed blast furnace slag, and then the lump and granule slag is processed using a stirring device. A method for producing a porous agglomerated soft rock type fish reef, which comprises: sprinkling cement onto the slag to the extent that it adheres to each other, and then piling up the slag into an arbitrary shape on a working floor and solidifying it.