JPH0342093A - Device for preventing sticking of shellfishes to inside surface of piping - Google Patents

Abstract

PURPOSE:To prevent the larvae of shellfishes from sticking to the inside surface of a piping by allowing the magnetotaxis bacteria replenished from a magnetotaxis bacteria replenishing device to be eaten by the larvae of the shellfishes as feed in a magnetizing chamber, magnetizing the larvae, separating and removing the larvae of the shellfishes in a magnetic filter device and guiding the wafer from which the larvae of the shellfishes are removed to the inflow port of the piping. CONSTITUTION:The magnetotaxis bacteria replenished from the magnetotaxis bacterial replenishing device 46 are allowed to eat the larvae of the shellfishes as feed in the magnetizing chamber 43 to magnetize the larvae 42 of the shellfishes. The larvae 42 of the magnetized shellfishes are in succession guided to a magnetic filter device 51 where the larvae are separated and removed. The water from which the larvae 42 of the shellfishes are separated and removed in such a manner is guided to the inflow port of the piping 41, by which the sticking of the larvae 42 of the shellfishes to the inside surface of the piping 41 is effectively prevented. The clogging and corroding of the piping 41 by the sticking of the shellfishes are thus effectively prevented.

Description

Detailed Description of the Invention [Object of the Invention] (Industrial Field of Application) The present invention relates to a shellfish adhesion prevention device that uses magnetotactic bacteria to prevent shellfish from adhering to the inner surface of piping, and is particularly applicable to nuclear RM plants. Prevents shellfish from adhering to the inner surface of plant piping such as
If the pipe is clogged, we will use a device to prevent shellfish from adhering to the inner surface of the pipe, which prevents corrosion.

(Prior art) In a nuclear power plant, steam generated in a nuclear reactor is sent to a steam turbine through a main steam system, and this steam turbine is driven to generate f1! The machine is driven to rotate. The steam that has done work in the steam turbine is condensed in a condenser and becomes condensate, and this condensate is returned to the reactor via the reactor condensate/water supply system.

On the other hand, a condenser that cools turbine steam houses a heat exchanger therein, and seawater is mainly used in this heat exchanger as a cooling medium for turbine steam.

This seawater is forcibly supplied from the water intake via the seawater system inflow piping to the heat exchanger by a circulating water pump, and the turbine steam is cooled with this seawater. The seawater that has cooled the turbine steam in the heat exchanger passes through the seawater system outflow piping and is discharged into the sea from the discharge port.

By the way, in the seawater system piping that supplies seawater for cooling turbine steam to the condenser, shellfish such as Fujitsubo and crow shells adhere to the inner surface of the piping, and the attached shellfish gradually grow, blocking the piping flow path. There is a risk of blockage or a reduction in the flow path area, and in this case, there is a risk that sufficient cooling water cannot be supplied to the condenser and its heat exchange function may be impaired.

Shellfish adhere to seawater piping in nuclear power plants, etc., and as the attached shellfish grows, various harmful effects occur.
Currently, during regular inspections, the inner surface of the pipe is cleaned with a high-pressure jet stream, and a working robot is sent into the pipe to scratch it to forcibly remove shellfish that have adhered to the inner surface of the pipe.

(Problems to be Solved by the Invention) Remove shellfish attached to the inner surface of the pipe. In conventional shellfish removal devices, there was a risk that the inner surface of the pipe would become aai in order to remove shellfish. The adhesion of 111 has a great influence on the corrosion of pipe metal materials, causing problems such as not only corrosion of pipes and 111!, but also clogging of pipe channels, which has become a major problem in nuclear power plants.

In conventional nuclear power plants, the main objective was to remove shellfish adhering to seawater pipes, and no special consideration was given to preventive measures to prevent the adhesion of shellfish.

The present invention was made in consideration of the above-mentioned circumstances, and effectively prevents shellfish from adhering to the inner surface of piping, thereby preventing damage to the piping and lubricating the piping.
! To provide an SN device for preventing shellfish from adhering to the inner surface of a pipe, which prevents corrosion and prevents clogging of the pipe.

Another object of the present invention is to provide a device for preventing shellfish from adhering to the inner surface of a pipe, which can separate and remove shellfish larvae before they are introduced into the pipe and effectively recover them.

[Structure of the Invention] (Means for Solving Problem a magnetotactic bacteria replenishing device, a magnetization tank for feeding the magnetotactic bacteria supplied from the replenishing device to shellfish larvae and magnetizing the larvae, and a magnetic filter device for separating and removing magnetized shellfish larvae. The water from which shellfish larvae have been removed by the magnetic filter device is guided to the pipe inlet.

Moreover, in order to solve the problems of the prior art described above, the present invention provides a magnetic filter device that is provided in the magnetic valve 11i tank formed on the downstream side of the magnetization tank, and a magnetic filter! Collection of shellfish larvae separated and removed by equipment 1! ! ! This provides a device for preventing shellfish from adhering to the inner surface of pipes that have been collected and processed in a tank.

(Function) The magnetotactic bacteria supplied from the magnetotactic class bacteria replenishing device for preventing shellfish adhesion to the inner surface of the pipe are fed to the shellfish larvae in the magnetization tank, thereby magnetizing the shellfish larvae. The magnetized shellfish larvae are then guided through a magnetic filter device;
Here it is separated and removed. Since the water from which shellfish larvae have been separated and removed is guided to the inlet of the piping, it is possible to effectively prevent shellfish larvae from adhering to the inner surface of the pipes, and to effectively prevent corrosion if the pipes become clogged due to adhesion of shellfish. can be prevented.

In addition, since it is possible to effectively prevent shellfish from adhering to the inner surface of the pipe, it is possible to eliminate the work of removing shellfish adhering to the inner surface of the pipe, reduce the number of times this work is required, and prevent damage to the inner surface of the pipe. .

In addition, the shellfish larvae separated and removed by the magnetic filter device can be collected and processed in the collection treatment tank in a very effective manner.

(Example) An example of the device for preventing shellfish from adhering to the inner surface of a pipe according to the present invention will be described with reference to the accompanying drawings.

FIGS. 1 and 2 show a typical example of a nuclear power plant using a boiling water reactor equipped with the device for preventing shellfish from adhering to the inner surface of piping according to the present invention. This nuclear power plant is equipped with a nuclear reactor (complex) building 10 and a turbine building 11 that are installed in parallel. A reactor containment vessel 12 is housed in the reactor building 10, and nuclear A reactor pressure vessel 13 constituting a steam generator of the reactor is housed therein.

On the other hand, the turbine building 11 includes a steam turbine 14, a power generating unit 115 driven by the steam turbine 14, and a condenser 16 that cools the steam that has worked in the steam turbine 14.

Thus, the steam generated within the reactor pressure vessel 13 is sent to the steam turbine 14 via the reactor main steam system 18, which drives the steam turbine 14 to perform work and rotate the power generator 8115. The steam that did work in the steam turbine 14 was 1! The water is then sent to the condenser 16, where it is cooled and becomes condensate.

This condensate is returned to the reactor pressure vessel 13 via the reactor condensate/water supply system 19 .

The condenser 16 also has a heat exchanger 2 in its casing 20.
A seawater system inflow pipe 22 is typically connected to the inlet side of the heat exchanger 21, and a seawater system outflow pipe 23 is typically connected to the exit side of the heat exchanger 21. A 22-kt seawater system inflow pipe extends from the water intake 24 of the sea (or a river), and is connected to a heat exchanger 21 via a circulating water pump 25 along the way, and this heat exchanger 21 cools the turbine steam. . The seawater that has cooled the turbine steam passes through a seawater system outflow pipe 23 and is discharged into the sea from a water outlet 26.

Further, as shown in FIG. 3, another water intake 28 near the water intake 24 is connected to a seawater heat exchanger (not shown) housed in a seawater equipment building 31 from a seawater flow path 30 via a seawater pipe (not shown). ) etc. This seawater heat exchanger and other components form part of the auxiliary equipment cooling system.

By the way, the vicinity of the inlet of the seawater system inflow pipe 22 from the water intake 24 to the condensate N20 and the seawater pipe 30 (hereinafter referred to as plant pipe 35) connected to the seawater heat exchanger, etc. is the fourth pipe. As shown in the figure, a shellfish adhesion prevention device 40 is provided.

This shellfish adhesion prevention bag ff40 is provided upstream of the inlet of the plant piping 35. Seawater intake 24 (2
The flow path 41 from 8) to the inlet of the plant distribution vI 35 includes a magnetization tank 43 that magnetizes shellfish larvae 42 such as Fujitsutsuka and crow shellfish, and a magnetic valve T11 tank 44 that separates and removes the magnetized shellfish larvae 42. It is divided into A mesh filter 45 is detachably provided on the upstream side of the magnetization tank 43, and the mesh filter 45 prevents grown shellfish, dirt, etc. from entering the flow path 41.

Further, magnetotactic bacteria are supplied to the magnetization tank 43 from a magnetotactic bacteria replenishing device 46 .

This fungal fungus is a single-celled bacterium that senses the earth's magnetic field and moves along magnetic lines of force, and contains magnetic fine particles (magnetite) of about 500 to 1000 ounces inside. I! &
For example, about 10 to 20 pieces are provided. magnetotaxis m
Bacteria sense magnetism and move along magnetic field lines, so they exhibit magnetotaxis.
A magnet (not shown) such as an electromagnet may be provided in the supply path 47 from the ll1111 supply device 46, and magnetotactic bacteria may be actively injected into the magnetized tank 43 by magnetic induction.

The magnetotactic bacteria 48 injected into the magnetization tank 43 are kept inside without flowing out due to the magnetic field formed by the magnetic force of a magnet 49 such as an electromagnet.

On the other hand, grown shellfish such as Fujitsubo and crow shellfish are prevented from entering the magnetization tank 43 by the mesh filter 45, but shellfish larvae 42 are guided into the magnetization tank 43 through the mesh filter 45. be done. The shellfish larva 42 guided to the magnetization tank 43 eats magnetotactic bacteria 48 as bait in the magnetization tank 43 and becomes magnetized. In this case, in order for the shellfish larvae 42 to efficiently eat the magnetotactic bacteria 48, the particulate bait preferred by the shellfish may be impregnated with magnetotactic bacteria.

Mollusk larvae 42 magnetized with magnetization 1!43 are guided to a magnetic separation tank 44 through a flow path. The magnetic separation tank 44 is surrounded by a strong magnet 50 such as a magnet 50, which constitutes a magnetic filter device ff151. , the magnetized shellfish larva 42 moves to the outside, and the shellfish larva 42 is in the center.
There remains a seawater current with very little water.

In addition, a plant pipe 35 is located at the center of the magnetic separation tank 44.
The inlet is open, and the seawater in which shellfish larvae 42 are separated and removed in the magnetic separation tank 44, and the seawater containing very few larvae 42 is guided to the plant piping 35, and passes through the plant piping 35 to the condenser. 16 and a seawater heat exchanger.

In this case, since the shellfish larvae 42 are separated and removed in the magnetic separation tank 44, it is possible to effectively prevent the shellfish larvae 42 from flowing into the plant piping 35. Therefore, it is possible to prevent shellfish larvae 42 from adhering to the inner surface of the plant piping 35, and it is possible to prevent clogging and corrosion of the pipes due to the attached shellfish.

In addition, since it is possible to effectively prevent shellfish from adhering to the inner surface of the plant piping 35, there is no need to scrape and remove shellfish adhering to the inner surface of the pipe, and the number of operations can be significantly reduced. Damage to the piping 35 can be prevented.

On the other hand, the shellfish larvae 42 that have been separated and removed by the gradient magnetic field within the magnetic valve l11f144 and migrated to the outside are subsequently guided to the recovery treatment tank 53 and recovered therein. Shellfish larvae 4 collected in the recovery treatment tank 53
2 is treated by damaging its biological functions by physical or chemical methods and killing the animals.

In addition, in one embodiment of the present invention, an example was shown in which the shellfish adhesion prevention device was applied to a nuclear power plant, but the present invention can also be applied to other plants that use seawater or river water, such as thermal power plants and chemical plan I. It can also be applied to

(Effects of the Invention) As described above, the device for preventing shellfish adhesion to the inner surface of piping according to the present invention allows shellfish larvae to be trapped in a magnetized tank using magnetotactic I [I11] bacteria supplied from the magnetotactic M bacteria as bait. The magnetized shellfish larvae were separated and removed using a magnetic filter device, and the water from which the shellfish larvae had been removed was guided to the inlet of the pipe, so that the shellfish larvae were not exposed to the inner surface of the pipe. It is possible to effectively prevent the adhesion of shellfish, and it is also possible to effectively prevent corrosion and damage if the piping is clogged due to adhesion of shellfish.

In addition, the shellfish larvae separated and removed by the magnetic filter device are collected in a collection treatment tank and can be easily processed.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the principle of a nuclear power plant to which the device for preventing shellfish adhesion to the inner surface of piping of the present invention is applied, Fig. 2 is a diagram showing a cross-sectional structure of a building provided in the nuclear power plant, and Fig. 3 4 is a partial layout diagram showing the layout of a nuclear power plant, and FIG. 4 is a simplified sectional view showing a device for preventing shellfish from adhering to the inner surface of piping provided in a seawater flow path of the nuclear power plant. 10... Reactor building, 11... Turbine building, 13
...Reactor pressure vessel, 14...Steam turbine, bottle, 1
5... Ti generator, 16... Condenser, 21... Heat exchanger, 22... Seawater system inflow pipe <flow path>, 23...
Seawater system outflow piping, 24... Water intake, 25... Circulating water pump, 26... Water outlet, 30... Wn water flow path, 3
1... Seawater equipment building, 40... Shellfish adhesion prevention device,
41... Channel, 42... Shellfish larva, 43... Magnetization tank, 44... Magnetic separation tank, 46... Magnetotactic I8 bacteria supply device, 49.50... Magnet, 51 ...Magnetic filter device, 53...Recovery processing tank. Diagram

Claims (1)

[Scope of Claims] 1. A magnetotactic bacteria replenishment device that replenishes magnetotactic bacteria upstream from the pipe entrance, and magnetotactic bacteria that are fed to shellfish larvae by feeding them with the magnetotactic bacteria supplied from this replenishment device. To the inner surface of a pipe, characterized in that it has a magnetization tank and a magnetic filter device for separating and removing magnetized shellfish larvae, and the water from which shellfish larvae have been removed by the magnetic filter device is guided to the pipe entrance. Shellfish adhesion prevention device. 2. The piping according to claim 1, wherein the magnetic filter device is provided in a magnetic separation tank formed on the downstream side of the magnetization tank, and the shellfish larvae separated and removed by the magnetic filter device are collected and processed in the collection processing tank. Device to prevent shellfish from adhering to the inner surface.