JPS6231631B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a biological removal device used in a seawater path for heat exchange or cooling in a seawater-using plant.

Conventionally, in nuclear power plants, chemical plants, and thermal power plants, seawater is circulated to remove various types of heat generated within the plant, to cool the fresh water used there, or to extract chemicals such as chlorine from seawater. Water is taken in from a water intake using a pump or a seawater pump, and sent to a condenser, heat exchanger, or chemical substance extraction device via seawater piping.

In this case, a filter such as a screen, mesh filter, or ball cleaning device is provided along the seawater circulation path to prevent fish and other living things from entering.

However, with the above method, shells and organisms that are too large to be removed by the screen or mesh filter may enter the pipes or heat exchanger, causing metal deterioration or corrosion. increases pressure loss,
This had the disadvantage that the capacity of the seawater pump had to be increased.

The present invention was developed in view of the above circumstances, and its purpose is to kill living things in seawater using electric current, and by removing them, metal deterioration and corrosion caused by living things adhering to pipes, heat exchangers, etc. It is an object of the present invention to provide a biological removal device that prevents overloading of seawater pumps, increases the efficiency of condensers, heat exchangers, etc., and improves safety during inspections. The above object is to provide a biological removal device installed in a seawater inlet route in a seawater-using plant, which includes a comb-shaped screen, a grid-shaped electrode connected to an external power supply, and a filter box along the direction of seawater inflow into the route. This is achieved by biological removal devices arranged in sequence.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a heat exchange system diagram in a seawater-using plant, and FIG. 2 shows a perspective view of an embodiment of the present invention.

The heat exchange system shown in FIG. 1 includes a water intake 1 that takes in seawater, a seawater pump 2 that transfers the taken seawater, a seawater pipe 3, a heat exchanger 4, a drainage pump 5, a discharge port 6, and the It is composed of a biological removal device 7 and the like attached to the water intake 1.

As shown in FIG. 2, the organism removal device 7 has a box shape as a whole, and a comb-shaped screen 8, a lattice-shaped copper plate electrode 9, and filter boxes 10 and 11 are arranged in this order.

The lattice-shaped copper plate electrode 9 is electrically insulated from its surroundings by an insulating material 12 and is connected to an external power source 14 via a power terminal 13 and an ammeter 23.

Further, the filter boxes 10 and 11 are arranged in the fourth filter box.
As shown in the figure, it has a large number of seawater permeation holes 10a, 11a of different sizes, and steel nets 15, 15 are attached to the front side of the seawater outflow side, and the filter boxes 10, 11 are equipped with a large number of seawater permeation holes 10a, 11a. A cleaning high-pressure nozzle 16 and a carcass intake port 17 are provided opposite to each other in order to remove the carcasses of the carcass. is connected to.

The grid-shaped copper plate electrode 9 and the filter box 1
0, 11 and the high-pressure cleaning nozzle 16 are attached to a support frame 20 as shown in FIG. 3, which is fixed to the water intake port 1 with bolts and nuts.

This support frame 20 is connected to an external power source 14 on the side opposite to the lattice-shaped copper plate electrode 9, so that the seawater entering from the water intake port 1 is energized.

In the biological removal device configured as described above, relatively large organisms and foreign objects in the seawater taken in from the water intake port 1 are removed by the comb-shaped screen 8, and small organisms that could not be removed here are shown in Figure 6. As shown, seawater flows between the grid-shaped copper plate electrodes 9, but the electric current supplied by the external power source 14 through the power terminal 13 and the support frame 20 flows through the seawater, causing the seawater to flow into the filter box 10 along with small foreign matter. Flow into.

The size of the permeation holes on the seawater inflow side and the outflow side of the filter box 10 are the same, but a steel net 1 as shown in FIG. 5 is arranged on the front side of the seawater outflow side.
Since the passage rate is lower than in 5, dead organisms and foreign matter accumulate here.

Incidentally, even smaller carcasses of living organisms and foreign matter that have passed through the filter box 10 are removed in the next filter box 11 in the same manner. The size of the hole 11a is made smaller than the size of the permeation hole 10a, and the removal rate is improved by the steel net 15.

The condition of dead organisms and foreign matter accumulated in the filter boxes 10 and 11 is detected by the differential pressure detector 21, and pure water is periodically injected from the high-pressure cleaning nozzle 16 and the gate valve 19 is opened. The discharge pump 5 is operated to open the carcass intake port 1 as shown in FIG.
7 to the discharge port 6.

If the current does not flow due to an accident with the external power supply 14, etc., living organisms may adhere to the filter boxes 10, 11 and the steel net 15, so in this case, remove the top cover 22 and remove the filter box from the support frame 20 Remove the steel net and replace it.

As explained above, according to the present invention, organisms in the seawater that have passed through the water intake are killed by the electric current and removed by the filter box, and the larvae and microorganisms of organisms that cannot be captured by the filter box are killed. It is discharged from the drain and does not adhere to the inner walls of the cooling system's seawater piping, condensers, heat exchangers, etc., preventing metal deterioration and corrosion and reducing overload of circulating water pumps, etc. It has a great effect on improving operating efficiency, extending the life of plant equipment, and improving safety.

[Brief explanation of the drawing]

Fig. 1 is a heat exchange system diagram in a seawater-using plant including the biological removal device of the present invention, Fig. 2 is a perspective view of the biological removal device of the present invention, Fig. 3 is a perspective view of the support frame, and Fig. 4 is a diagram of the filter. FIG. 5 is a front view of the steel net, FIG. 6 is a perspective view of the lattice-shaped copper plate, and FIG. 7 is a perspective view of the carcass inlet. 1... Water intake, 2... Seawater pump, 3... Seawater piping, 4... Heat exchanger, 5... Discharge pump, 6
...Discharge port, 7...Biological removal device, 8...Comb-shaped screen, 9...Grid-shaped copper plate electrode, 10, 11
...Filter box, 14...External power supply, 15
...Steel net, 16...High pressure nozzle for cleaning, 1
7...Carcass intake port, 19...Gate valve, 20...Support frame, 21...Differential pressure detection meter.

Claims (1)

[Claims] 1. A biological removal device installed in a seawater inlet route in a seawater-using plant, which includes a comb-shaped screen, a grid-shaped electrode connected to an external power source, and a filter along the direction of seawater inflow into the route. A biological removal device characterized in that boxes are arranged in order. 2. The biological removal device according to claim 1, wherein the filter box is provided with a high-pressure nozzle for cleaning.