JP3103504B2 - Water reforming method using steelmaking furnace slag - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a steelmaking furnace slag to improve the quality of water flowing through waterways such as rivers, and is necessary for the propagation and growth of freshwater fish, shellfish, and aquatic plants. The present invention relates to a water reforming method that provides a favorable environment.

[0002]

2. Description of the Related Art The inflow of organic matter such as domestic wastewater into rivers has been increasing with the sophistication of life, but the flow velocity of water flowing along river bottoms and along the wetted parts of banks in rivers flowing slowly is slow. In this case, the sediment easily accumulates on the riverbed and the side of the bank, and the surface of the river is smooth and the entrainment of air into the water is small, so that the natural purification action of the river is weak. If this occurs over a long period of time, the landscape will be impaired, and odorous gas will be generated, which is a major environmental problem.

On the other hand, conventionally, fish and shellfish have been artificially grown,
As a method for propagation, a method of submerging steel, stone, wood, etc. into water to form an artificial reef, thereby forming a fish reef space, in which seaweed and phytoplankton are settled and inhabited, and a seaweed bed is formed Is widely used.

[0004] However, in order to artificially grow fish and shellfish that inhabit freshwater, it has conventionally been an essential condition that the water environment and the soil environment are as natural as possible and clean. Until very recently, the best way to protect the declining seafood and its habitat for the wildlife involved in the food chain is to approach the natural environment as much as possible and eliminate artificial structures. This is considered the only measure, and measures have been taken to maintain or restore the natural habitat. In addition, the landscape in the river should be as close to nature as possible and suitable for plants and organisms in consideration of the environment. It has become

[0005] However, recent studies have reported that shellfish more favorably adhere to structures such as artificial concrete than natural stones in rivers. In rivers, it has been confirmed that shellfish Kawanina and fireflies that feed on the shellfish are inhabited.Therefore, it is an environment in which chemical components necessary for growth are supplied in an appropriate amount rather than being close to nature and clean. Is considered to be the first condition for protecting and raising the habitat of wildlife such as fish and shellfish.

[0006] The elements necessary for the growth are, for shellfish, calcium, which is an element essential for shell formation, and silicic acid, which is essential for the growth of algae such as diatoms, which feed on shellfish.
Others include phosphoric acid. These concentrations are generally recommended in the ranges shown in Table 1. In addition, the dissolved oxygen amount is 90 to 1
00% is also an essential condition for the growth of these organisms.

[0007]

[Table 1]

Conventionally, for various purposes, attempts have been made to artificially breed aquatic seafood and seaweeds while satisfying these habitat conditions. Although there are many such examples, a fish reef block using steel slag (slag) generated in the steel manufacturing process in the steel industry is disclosed in Japanese Patent Application Laid-Open No. 54-5 / 1979.
No. 4892, JP-A-56-5032, JP-A-58-1
No. 3334, etc., all of which are aimed at seawater, and are characterized by the fish reef itself and its production method, and are not intended for freshwater.

[0009]

As a material for supplying an element suitable for the condition of shellfish living in freshwater, there are slags such as steelmaking furnaces (flat furnaces and electric furnaces) generated in the steel making process as described above. . However, these slags generally have a high water solubility, and there is a problem that the active ingredient easily flows out.

As shown in FIG. 1, the present inventors conducted a dissolution test on converter slag, and as shown in FIG. 1, a water flow (0.05 m
/ Min) or less, in a powder slag having a particle size of 10 mm or less due to stagnation of water, calcium excessively flows out in the slag component, and as a result, the pH of the water changes to a strong basicity and pH 8.0. There is a problem that the conditions for the shellfish are not satisfied and the conditions for the occupation of the shellfish are not satisfied. Further, when the particle size is 10 mm or less, the slag is eluted at a high rate due to the increase in the surface area. Under such circumstances, early solution of these problems has been strongly desired.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in order to advantageously solve the above-mentioned problems, and its gist is to use a massive slag generated from a steelmaking furnace, Alternatively, a fine particle is coagulated by adding a coagulant such as cement and the amount of dissolution is suppressed to complete a water quality improvement system. The means are as follows. (1) The massive steelmaking furnace slag is immersed in running water in a water channel ,
Running water of CaO: 8~20mg / liter, SiO _{2: 2}
0~100mg / liter, P ₂ O _5: 0.5~1.0
It is suitable for growing freshwater fish and shellfish, and diatoms serving as food for shellfish by adjusting the contact area with the massive steelmaking furnace slag so that the pH becomes 6.0 to 8.0 mg / liter. A water reforming method using steelmaking furnace slag, characterized by providing a habitat environment. (2) The water reforming method using the steelmaking furnace slag according to (1), wherein the adjustment of the contact area is performed on one or both of the grain size of the massive steelmaking furnace slag and the surface area of the steelmaking furnace slag. . (3) The water reforming method using the steelmaking furnace slag according to (1) or (2), wherein the massive steelmaking furnace slag is obtained by solidifying a fine-grained steelmaking furnace slag with cement or the like.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Table 2 shows the chemical components of fish reefs generally used in breeding fisheries and the like together with converter slag. As is clear from Table 2, the converter slag is 10
~ 50% silicic acid, 20-80% calcium oxide,
It contains 1 to 10% of phosphoric acid, etc., and is suitable for supplying silicate, calcium ions, and phosphates. On the contrary, there are few harmful substances such as sulfur. In addition, since it is a by-product during refining, there is an advantage that it can be obtained at low cost.

[0013]

[Table 2]

The present inventors have paid attention to this point, and as a result of repeated research and development for effective use of steelmaking furnace slag,
The present invention has been completed, and it is not necessary to simply use steelmaking furnace slag. There is a slag particle size suitable for a water channel (water volume) used and optimization of a steelmaking furnace slag area in contact with water. Occupy a large factor.

According to the present invention, converter slag is selected as a typical example of steelmaking furnace slag, and the particle size of the slag is 1
By using a lump of 0 to 200 mm, the slag is gradually dissolved, and calcium ions, silicates, and active ingredients such as phosphates can be continuously eluted,
At the time of constant effluent (5 liter / min), as shown in Table 3, the amount of the above components in the waterway was maintained at an appropriate level, and
Was found to be within the range of 6.0 to 8.0 suitable for the growth of fish and shellfish.

[0016]

[Table 3]

The surface contact area of the converter slag varies greatly depending on the shape of the slag. The closer to the sphere, the smaller the contact area with the outer surface, and if the surface has many irregularities, the larger the contact area becomes. . Therefore, depending on the slag shape, it is necessary to adjust not only the slag particle size but also the amount of slag to be installed according to the shape.

Furthermore, in the present invention, not only the steelmaking furnace slag is used alone, but also a fine-grained steelmaking furnace slag is solidified with cement or the like to form a block of an appropriate size, and the same method is used. It is used by appropriately setting the amount. In this case, the effective component of the steelmaking furnace slag is naturally reduced depending on the amount of the binder such as cement, so that the amount thereof becomes larger than that of the simple steelmaking furnace slag.

Further, according to the present invention, the direct sunlight is appropriately applied to the massive steelmaking furnace slag, so that the water temperature is appropriately increased and an environment favorable for the growth of underwater plants such as aquatic plants and algae is formed. Also, since the shade is appropriately formed below the massive steelmaking furnace slag, a favorable environment for resting aquatic organisms is formed. In addition, the location of the massive steelmaking furnace slag where water is circulated is very good, so that an environment rich in oxygen and nutrients can be formed.

[0020]

FIG. 2 shows a bird's-eye view of a river (flow path width 1 m) having a length of about 15 m and a width of about 6 m as an example.
FIG. 3 is a plan view of this embodiment. A massive converter slag 1 according to the present invention is installed in a part of the water channel 3. The flowing water becomes turbulent by the weir 2 and almost dissolves the dissolved oxygen, and then touches the slag 1 to elute the active ingredient. Such a situation is configured to be repeated.

That is, as shown in FIG. 3, the slag used is a substantially spherical massive converter slag (diameter of 10 to 200 m).
m), 20 kg of massive converter slag having an uneven surface (average diameter of 10 to 50 mm), and a massive converter slag (diameter of 10 to 50 mm) obtained by solidifying 80% of fine converter slag with 20% of cement. Three types of 20 kg were respectively charged and installed. As a result, at a flow rate of about 10 to 20 liters per minute, the pH of the inflow water was the same as shown in Table 3 above.
Was 6.8, the pH of the effluent was within the range of 6.0 to 8.0, and the amount of components could be kept in the target range.

[0022]

[Table 4]

Table 4 shows the inflow water and outflow water.
The analysis results of the components are also shown. From this, it can be seen that the ion concentrations of calcium, silicic acid and phosphoric acid in the water are surely increased. Diatoms were generated in about 10 days when water was passed through this passage. When shellfish such as kawana were released, they grew smoothly.

[0024]

According to the present invention, by installing a steelmaking furnace slag having an appropriate particle size or an appropriate contact area at an appropriate position in a flowing water channel, the pH of the steelmaking furnace slag can be adjusted by the effective components of the steelmaking slag. It is an industrially useful invention that can be adjusted, maintain the habitat of wildlife in a good condition, help prevent pollution of rivers, provide inexpensive and stable supply, and make effective use of steelmaking furnace slag.

[Brief description of the drawings]

FIG. 1 is a diagram showing a comparison of changes in pH under elution conditions.

FIG. 2 is a diagram showing one embodiment of the present invention as viewed from above from above.

FIG. 3 is a plan view showing a part of the embodiment of the present invention.

[Explanation of symbols]

 1 massive slag 2 weir for oxygen saturation 3 waterway

──────────────────────────────────────────────────続 き Continued on the front page (72) Kinya Narushige, Inventor 4387 Usino, Makama-cho, Higashi-gun, Oita Prefecture (56) References JP-A-5-50085 (JP, A) (58) Fields investigated (Int.Cl . ^7, DB name) A01K 61/00 A01K 63/04

Claims (3)

(57) [Claims] 1. A massive steelmaking furnace slag is immersed in running water in a water channel, and CaO in the running water: 8 to 20 mg / liter, Si
O ₂ : 20 to 100 mg / liter, P ₂ O ₅ : 0.5
１．０1.0 mg / liter, and pH = 6.0-8.0, by adjusting the contact area with the massive steelmaking furnace slag to obtain freshwater fish and shellfish, A water reforming method using steelmaking furnace slag, wherein the habitat is suitable for growing. 2. The steelmaking furnace slag according to claim 1, wherein the adjustment of the contact area is performed on one or both of the grain size of the massive steelmaking furnace slag and the surface area of the steelmaking furnace slag. Water reforming method. 3. The water reforming method using steelmaking furnace slag according to claim 1 or 2, wherein fine-grained steelmaking furnace slag is solidified with cement or the like as the massive steelmaking furnace slag.