JPS6261722B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for preventing aquatic organisms such as shellfish and algae from adhering to and propagating in waterways by dissolving copper into water.

(Prior Art) Copper is extremely harmful to living things, so a copper compound is applied to the bottom of a ship to prevent shellfish, seaweed, etc. from growing on the hull.

In addition, aquatic organisms such as shellfish grow in the intake channels of factories that use large amounts of water or seawater, narrowing the flow path area. At nuclear power plants, cooling capacity decreases, so it is necessary to prevent the growth of marine organisms such as shellfish and seaweed.

Therefore, it is possible to prevent marine organisms from growing in waterways by leaching copper into seawater, but copper is extremely harmful to living things, and seawater containing large amounts of copper ions cannot be used in the ocean. Continuously flowing water into waterways is undesirable due to pollution problems, and it can also cause pitting corrosion, which can cause failures in cooling pipes, pumps, and other equipment at power plants. Measures to prevent the propagation of marine organisms such as marine organisms are not being utilized.

Therefore, the current situation is that shellfish, seaweed, etc. that have adhered to waterways are removed periodically, for example once a year, using tools, etc., and this work requires a considerable amount of effort and time. It was also difficult to dispose of marine life such as shellfish and seaweed.

(Object of the invention) The object of the present invention is to prevent aquatic organisms such as shellfish from adhering to waterways by eluting copper into water, and to recover copper ions in water by electrodeposition means. .

(Structure and operation of the invention) The present invention provides copper or copper alloy lining treatment to the inner periphery of the waterways of power plants or various factories that use large amounts of water or seawater, especially the intake waterways, thereby immersing copper into the water. A pair of electrodes are disposed in the waterway downstream from the position where the copper or copper alloy lining is applied, and these electrodes are provided externally. This is a method for preventing the adhesion of shellfish, algae, etc. in waterways, which is characterized by connecting to a DC power source, polarizing the water, and collecting copper ions present in the water by adhering them to a cathode.

In the above configuration, both of the pair of electrodes are metal bodies made of conductive metal, and the anode is made of titanium platinum, triiron tetroxide, lead silver, graphite, etc., which are difficult to dissolve into seawater as metal ions. On the other hand, the cathode is preferably a metal body made of inexpensive soft iron, and is particularly preferably a metal body with holes so that a large amount of copper ions can adhere thereto.

The current density between the positive and negative electrodes is preferably about 0.5 mA/cm ² . This causes Mg to be applied to the cathode when energized.
Inorganic substances mainly composed of (OH) ₂ and CaCO ₃ adhere to the cathode, but when the current density exceeds 1 mA/cm ² , the amount of inorganic compounds that adhere to the cathode increases and the copper ion recovery efficiency becomes low compared to the power consumption. Deteriorate. On the other hand, even if the current density is too low, copper ions cannot be recovered sufficiently, so 0.5
Around mA/cm ² is desirable.

(Example) Next, examples of the present invention will be described.

In Figures 1 to 3, a waterway is equipped with an intake channel 2 that takes in seawater, and a drainage channel 4 that drains the seawater into the sea again after the seawater taken in from the intake channel 2 is utilized within the power plant 6. A mild steel plate 14 coated with a 1 mm thick copper lining 12 by cladding, plating or other means is applied to the inner peripheral wall of the concrete frame 10 constituting the water intake 2A over several meters in the longitudinal direction of the waterway. and lay it. On the other hand, a metal body 22 made of titanium and platinum is installed inside the concrete frame 20 that constitutes the drain port 4A of the drain channel 4.
and a wire mesh 24 made of soft iron are provided on the bottom and side walls of the support members 26A and 26B, respectively.
Support and fix by. The upper ends of this metal body 22 and wire mesh 24 are connected to an external DC power source 28.
is connected to the metal body 2, and when energized, the metal body 2
2 serves as an anode, and wire mesh 24 serves as a cathode.

Note that the support members 26A and 26B are insulated, and no current will escape from them.

1 per day from the copper lining part 12 of the water intake 2A
Approximately 20 μg of copper per cm ² dissolves into the seawater, and the seawater in the waterway contains copper ions, killing marine organisms such as shellfish in the waterway from the water intake 2A to the drain 4A. Or weaken it to prevent it from adhering to the inner circumferential wall of the waterway.

On the other hand, at the drain port 4A, electricity is applied between the metal body 22 and the wire mesh 24 to give a current density of 0.5 mA/cm ² .
Then, copper ions (Cu ²⁺ ) in the seawater adhere to and precipitate on the outer surface of the wire mesh 24, which serves as a cathode.

In addition to copper ions, the wire mesh 24 contains CaCO ₃ and Mg.
Inorganic substances such as (OH) ₂ also adhere, but the amount is not large as they are washed away by the water current. Furthermore, if there is a large amount of inorganic matter attached, the cross section of the drain port 4A is made smaller to increase the flow velocity and reduce the amount of inorganic matter attached.

In this example, a platinum titanium metal body that is difficult to dissolve into seawater during energization is used as an anode, but instead of this, a metal body of triiron tetroxide has the same effect, and a platinum titanium metal body is used as an anode. It is preferable to use a metal body of triiron tetroxide because it can be obtained at a lower price.

In this example, since a wire mesh was used for the cathode, the surface area of the cathode was increased, and a large amount of copper ions could be attached and collected. In addition, wire mesh has many gaps,
Even if they are arranged perpendicular to the flow, the flow will not be blocked and no excessive external force will be applied to the support members 26A, 26B.

According to this embodiment, the cross section of the waterway will not be pinched by adhesion of marine organisms such as shellfish and seawater.

Furthermore, in the above embodiment, the inner circumferential wall of the water intake 2A of the waterway is treated with copper lining, and a copper ion recovery means is provided in the drainage port 4A. flow 4b
By lining the waterway with copper or copper alloy and installing copper ion recovery means at the drain 4A, it is possible to prevent marine organisms such as shellfish from adhering to the waterway, and to protect the various devices and equipment in the power plant 6. Pitting corrosion will no longer occur in equipment, etc.

In the above embodiment, a method for preventing the adhesion of shellfish and the like in a waterway that carries seawater has been described, but the method can also be applied to a waterway that carries fresh water instead of seawater.

(Effects) According to the present invention, the adhesion and propagation of aquatic organisms such as shellfish in waterways is prevented, and the harmful copper ions used to prevent adhesion of aquatic organisms are recovered, which causes pollution problems. Not at all.

[Brief explanation of the drawing]

Figure 1 is a plan view of the power plant with intake channel and drainage channel, Figure 2 is a cross-sectional view of the intake channel with copper lining treatment, and Figure 3 is the drainage channel equipped with copper ion recovery means. FIG. 1...Intake channel, 2A...Intake port, 4...Drainage channel, 4A
...Drain port, 10, 20...Concrete frame, 1
2... Copper lining, 14... Mild steel plate, 22... Metal body serving as an anode, 24... Wire mesh serving as a cathode, 28... DC power source.

Claims (1)

[Claims] 1. A method for preventing shellfish, algae, etc. from adhering to a waterway by dissolving copper into water, in which the inner periphery of the waterway is lined with copper or copper alloy as an anode material, and the copper Or shellfish and algae in a waterway characterized by placing a pair of electrodes downstream of the position where the copper alloy lining treatment is applied and polarizing the electrodes by connecting them to a DC power source to attach copper ions to the cathode. How to prevent such adhesion. 2. The method for preventing adhesion of shellfish, algae, etc. in a waterway according to claim 1, wherein the cathode is made of a wire mesh.