KR100366737B1 - Operation method of seawater cooling system - Google Patents

Abstract

The present invention prevents the adhesion of sea creatures to equipment and piping. Moreover, the temperature layer formed in the circulating warm water is removed, and the temperature of the circulating water is equalized. The present invention forms a circulation cycle consisting of a sea water circulation system and a hot water circulation system, and installs a warming device in the hot water circulation system to produce hot water to be circulated. In addition, an auxiliary system is formed inside the hot water circulation system, the circulation water is stirred, and the mixing of the circulation water and the hot water is promoted. By circulating the hot water, sea creatures can be prevented and the removal of sea creatures is not required. In addition, it is possible to prevent the occlusion of equipment piping by the sea creatures, and to prevent the deterioration of the heat exchanger due to the decrease in the amount of water flow.

Description

Operation method of seawater cooling system

The present invention relates to a cooling installation of a heat exchanger used in a power plant, in particular a cooling installation of a heat exchanger using sea water as the cooling water.

When cooling a heat exchanger such as a condenser or an auxiliary equipment cooler using sea water, the attachment and growth of sea creatures to the heat exchanger or the pipe becomes a problem. The attachment and growth of sea creatures reduces the amount of water flowing through them by closing heat exchangers and piping. There is a problem that the performance of the heat exchanger is deteriorated due to the reduction of the amount of seawater to be fed and the original cooling capacity is not obtained.

For this reason, it was necessary to work to remove sea creatures. In particular, when the piping was long (sometimes about 1 km), the removal of these sea creatures took a long time. In addition, the cost for the work has also increased considerably.

Conventionally, a method for preventing marine organisms from adhering to a pipe is disclosed in Japanese Unexamined Patent Publication No. 55-17016, which heats seawater supplied to a seawater circulation system such as a condenser or an auxiliary equipment cooler to produce marine organisms. It was to suppress.

In the prior art, a temperature difference occurs between cold seawater filled in the circulating water pipe and warm seawater flowing into the circulating water pipe by circulation of hot water before circulating the heated sea water (hot water). Due to the temperature difference (incomplete mixing), a density difference occurs in the circulating water in the pipe, and a temperature layer is formed. Accordingly, there is a fear that sea creatures will survive in the cold water layer.

An object of the present invention is to focus on the formation of a temperature layer in hot water circulating, to uniformize the temperature of the circulating water at an early stage, and to eliminate the cold water layer. And it is providing the cooling installation of the heat exchanger which can remove sea creature suitably.

The cooling equipment of the heat exchanger using the sea water of the present invention relates to a plant device cooled by sea water, for example, a heat exchanger (multiplier) which heat exchanges between steam and sea water. And it has a seawater circulation system which introduces seawater to a plant apparatus, and discharges seawater from a plant apparatus. Moreover, the hot water circulation system provided with the heating apparatus which communicates the inlet side piping of a plant equipment with the outlet side piping of a plant equipment, and heats the flowing sea water.

Moreover, it is preferable that this invention has the auxiliary system which communicates the inlet_pipe of a plant apparatus with the outlet_pipe of a plant apparatus, and is formed inside the hot water circulation system. This auxiliary system forcibly stirs the seawater. This auxiliary system can also be used as a ball cleaning system or a cooling system for an auxiliary equipment cooler.

When the seawater supplied from the hot water circulation system or the auxiliary system is introduced into the seawater circulation system, the seawater is forcibly stirred, so it is preferable to supply the seawater by turning or spraying it. Moreover, while circulating hot water between a seawater circulation system and a hot water circulation system, it is preferable to stir seawater using an auxiliary system.

In the present invention, the inlet pipe and the outlet pipe each have a seawater inlet valve and a seawater outlet valve, and the hot water circulation system is preferably formed inside the seawater inlet valve and the seawater outlet valve. The hot water circulation outlet valve is preferably installed in the hot water circulation system branched from the inlet pipe, and the hot water circulation inlet valve is provided in the hot water circulation system branched from the outlet pipe.

The present invention also relates to a method of operating a heat exchanger cooled by sea water. First, an inlet valve formed in an inlet pipe for introducing seawater into the heat exchanger and an outlet formed in an outlet pipe for discharging seawater from the heat exchanger Close the valve. Next, the seawater circulating in the seawater circulation system formed by the inlet pipe and the outlet pipe and the hot water circulation system formed in communication with the inlet pipe and the outlet pipe are heated by a warming device provided in the hot water circulation system.

In addition, the present invention preferably has a step of discharging seawater from the seawater circulation system and a step of supplying seawater circulated to the hot water circulation system. In addition to the step of circulating the heated seawater into the seawater circulation system and the hot water circulation system, it is preferable to have a step of maintaining the circulated seawater at least in the seawater circulation system.

That is, this invention is achieved by stirring-mixing low temperature seawater and high temperature seawater in the hot water injection point formed in the inlet side of a seawater circulation system. Moreover, the stirring of the circulation water is accelerated by the circulation water flowing through the auxiliary system provided inside the hot water circulation system. The flow rate of the seawater flowing through the seawater circulation system can be increased by operating the auxiliary system circulation pump installed in the auxiliary system.

The cooling installation of this invention is applied to the cooling system of the condenser and auxiliary equipment cooler (heat exchanger) used for the turbine installation of a thermal power plant and a nuclear power plant.

In the case of a power generation plant composed of a plurality of power generation units (hereinafter referred to as {multiple shafts}), the communication pipes taken out from each shaft join each other inside the seawater inlet valve and the seawater outlet valve. Thereby, hot water can be supplied to the seawater circulation system of each axis with one heating device.

In the present invention, the exclusion (seashell removal) of sea creatures such as shellfish of the seawater circulation system is performed on a specific axis in which power generation is stopped at night or on weekends. First, the seawater remaining in the seawater circulation system is discharged. Next, seawater is supplied from the other shaft during power generation via a contact pipe. The seawater is boosted by a pump installed in the liaison tube, and then warmed up to the lethal temperature of sea creatures by a heating device. Thereafter, the warmed seawater is led to the seawater circulation system of the shell removal target shaft, and the equipment and piping are filled with hot water. And it maintains this hot water and / or circulates this hot water over the considerable period which sea creatures reach fatality. In addition, as necessary, the amount of heat lost to equipment and piping may be supplemented with a heating device to further ensure shelling effect.

Moreover, it is preferable to have a means for forming a free liquid surface in a part of an apparatus, piping, etc., and a means for pressurizing the free liquid surface. Moreover, it is preferable that they are in the highest position in a perpendicular direction in a system, and it is preferable to carry out during shell removal operation.

Moreover, it is preferable to form the bypass flow path which communicates with the upstream and downstream of a seawater system outlet valve, is thinner than the piping which forms a seawater circulation system, and is connected to the piping which has a valve.

When the hot water remaining in the seawater circulation system is discharged after the seawater circulation system is filled with hot water to reach the lethality, it is preferable to replace the hot water with the cooling water by supplying seawater from the other shaft via the contact pipe. .

Moreover, it is preferable to gradually discharge hot water in a system via a bypass flow path.

Moreover, it is preferable to have a means which detects the water level of the seawater which flows in the piping which comprises a seawater circulation system.

Moreover, it is preferable that this invention has a means which detects the substitution of the hot water in a system with cooling water, and a means which stops supply of the cooling water from another axis | shaft using the signal from this means.

The seawater cooling system of the thermal power plant and nuclear power plant of the present invention pumps seawater into a heat exchanger via a circulating water pipe or a water channel. After cooling the heat exchanger, the seawater is discharged to the sea again through the circulation water pipe or the water channel.

As a method of preventing the adhesion and growth of sea creatures, a method of injecting chemicals, a method of blowing hot air, a method of returning and recycling the sea water from the condenser to an auxiliary device cooler, a method of washing using a ball, and the like May be combined.

Hereinafter, the operation of the present invention will be described.

The method for suppressing reproduction of sea creatures by supplying hot water to the seawater circulation system (the present invention) effectively removes sea creatures by equalizing the temperature of the circulation water of the seawater circulation system. In addition, by making the temperature of the circulating water uniform, the temperature difference of the seawater in the pipe forming the seawater circulation opening can be eliminated, and the influence on the pipe and the lining due to thermal stress can be alleviated.

The hot water circulation system is installed to connect the circulating water system inlet side and the circulating water system outlet side, and has a heating device and a pump for circulating the hot water. The heating device is a device that heats seawater to a set temperature at the time of hot water circulation, and is controlled by a signal of a temperature detector. The hot water circulation pump is a device for forcibly transferring hot water, and circulates hot water through a hot water circulation crab container, a sea water circulation system, and an auxiliary system.

The auxiliary system connects the circulating water system inlet side and the circulating water system outlet side and is installed inside the hot water circulation system. The confluence and branch points of the seawater circulation system, i.e., the outlet and inlet of the auxiliary system, are arranged at a location between the circulating water injection point and the heat exchanger inlet and the circulating water recovery point and the heat exchanger outlet. In addition, the auxiliary system has an auxiliary system circulation pump and can forcibly return the circulating water in the system by the operation of the auxiliary system circulation pump. Then, the flow rate of the circulating water in the seawater circulation system from the outlet of the auxiliary system to the inlet can be increased.

The present invention focuses on a heat treatment method in which sea creatures do not adhere to equipment and piping in high temperature seawater, and supplies hot water with a large specific heat to kill sea creatures. For example, it was found that sea creatures died in several hours in an atmosphere of 35 ° C., and dozens of minutes in an atmosphere of 40 ° C.

Supply method of hot water,

(1) Method of replacing cold water in equipment and piping with hot water by injecting hot water from one end of the pipe and draining cold water from the other end while the equipment and piping are filled with cold water;

② After discharging the cold water in the equipment and piping, the method of injecting hot water is considered. In addition, it is preferable to use the method of (2) when it is applied to a large and long circulating water piping.

In the method of ①, the hot water fills only the upper part of the pipe under the influence of buoyancy, and the cold water in the lower part of the pipe remains unsubstituted with hot water. And there is a possibility that sea creatures reproduce in the lower part of the pipe. The phenomenon in which hot water and cold water are separated in the height direction is remarkable because the larger the diameter of the pipe, the smaller the flow rate during substitution.

In addition, when the method of ① is applied to a system in which a parallel circuit having a large gap in the flow resistance coefficient of the pipe coexists, for example, a system combining a cooling system of a plurality of devices and a cooling system of an auxiliary equipment cooler, the flow resistance coefficient is large. The hot water is not supplied to the circuit sufficiently, and the effect of shell removal is insufficient.

In addition, since the method of ① has a mixture of cold water and hot water, there is a drawback that it takes time to increase the temperature in the cold water discharge part. For example, in numerical simulation of continuous injection of hot water at 50 ° C. from one end of a circulating water pipe and discharging cold water from the other end, sea water is discharged to the lethal temperature of the shellfish (eg 40 ° C.) at the discharge part of the cold water. It was found that the rising required 1.5 times the amount of hot water in the pipe. As a result, when the quantity of water retained in the pipe is large, it takes a long time to obtain the effect of sufficient shell removal.

In contrast, the method of ② does not have these problems. In particular, in the method of ②, since the pipe is empty, the injected hot water spreads quickly to the end of the system. In addition, the required quantity is the same as the quantity retained in the pipe, which is less than the method of ①.

As a result, by using the method of ②, the effect of shellfish removal in a short time with little hot water is obtained. This is a particular advantage for a combined cycle plant (combined cycle plant) that starts and stops every day in response to fluctuations in power demand.

The present invention can reduce the temperature difference between the circulating water by performing stirring mixing of the seawater at the circulating water injection point and / or the auxiliary system outlet. In addition, the density difference between seawater is reduced, the formation of temperature impulses is suppressed, the congestion of the cold water layer in the pipe is eliminated, the adhesion of sea creatures is effectively prevented, and reproduction is suppressed.

A method of preventing the adhesion of sea creatures by the hot water circulation of the present invention will be described with reference to FIG. 1 (Example 1).

The hot water circulation system 101 is installed to connect the circulation water system inlet side 109 and the circulation water system outlet side 110. A heat exchanger 113 is installed between the inlet side 109 and the outlet side 110. The warm water circulation system 101 is provided with a heating device 103 and a pump 102 for hot water circulation.

When the power plant is operating, the seawater inlet valve 114 provided at the inlet side 109 and the seawater outlet valve 115 provided at the outlet side 110 are opened, and the hot water circulation system 101 is opened. The installed hot water circulation outlet valve 104 and the hot water circulation inlet valve 105 are closed. The heat exchanger 113 exchanges heat using seawater sucked into the circulating water pump 200.

Then, when the power generation plant related to the heat exchanger 113 is stopped, the seawater inlet valve 114 and the seawater outlet valve 115 are closed and the hot water circulation outlet valve 104 and the hot water circulation inlet valve 105 are closed. Open). At this time, the valve formed in the pipe connected to the other shaft is closed.

The seawater guided to the hot water circulation system 101 is heated using the heating device 103, and the seawater is pumped to the seawater circulation system 108 using the hot water circulation pump 102. By circulating hot water, it suppresses reproduction of sea creatures.

The hot water circulation range is the seawater circulation system and the hot water circulation system 101 from the seawater inlet valve 114 to the seawater outlet valve 115 via the heat exchanger 113.

There are various times to think about the time when the reproduction of sea creatures is suppressed. This embodiment takes into account the weekend when the power plant stops.

Moreover, the procedure of operation for suppressing reproduction of sea creatures is demonstrated below.

(1) First, the hot water circulation outlet valve 104 and the hot water circulation inlet valve 105 are opened, and the hot water circulation system 101 is filled with sea water to perform wet soaking.

(2) Then, the seawater outlet valve 115 and the seawater inlet valve 114 are closed while adjusting the flow rate of the circulating water pump 200 in consideration of the closing pressure.

(3) Then, the circulating water pump 200 is stopped while the seawater circulation system 108 is filled with seawater.

(4) Next, the hot water circulation pump 102 is started to form a circulation cycle of the hot water circulation system 101 to the seawater circulation system 108 to the hot water circulation system 101.

(5) In parallel, the seawater is heated by hot water of about 50 ° C using the heating device 103, and the hot water is circulated. The heating of the seawater in the heating device 103 is performed by supply of auxiliary steam. The heating device 103 supplies water vapor to seawater as circulating water, and these produce hot water by mixing.

(6) After the hot water is filled in the circulation cycle, the hot water is circulated by one cycle.

In this embodiment, the auxiliary system 116 is further provided inside the circulation cycle of the hot water circulation system 101 to the seawater circulation system 108 to the hot water circulation system 101.

The auxiliary system 116 is a predetermined position between the circulating water injection point 106 and the heat exchanger inlet 111 provided at the circulating water system inlet side 109, and a circulating water recovery point provided at the circulating water system outlet side 110. 107 and the heat exchanger outlet 112 are provided to connect a predetermined position.

The operation procedure in the case of using an auxiliary system is demonstrated below.

(1) First, the auxiliary system inlet valve 121 and the auxiliary system outlet valve 120 are opened to fill the auxiliary system 116 with seawater.

(2) When the hot water is circulated in the circulation cycle, the auxiliary system circulation pump 117 is operated in parallel to form a small circulation cycle of the auxiliary system 116 to the seawater circulation system 108 to the auxiliary system 116. .

Using the auxiliary system circulation pump 117, the flow rate of the seawater flowing through the auxiliary system 116 is increased to about 3 to 4 m / s, and the temperature is uniformed by stirring the circulating water by the sorting from the outlet 118 of the auxiliary system. .

In the initial stage of the hot water circulation operation, the low temperature seawater of the seawater circulation system outlet side 110 is recovered from the inlet 119 of the auxiliary system, and the high temperature seawater of the seawater circulation system inlet side 109 from the outlet 118 of the auxiliary system. Inject. This contributes to the uniformity of the condo of the circulating water.

In the middle and later stages of the hot water circulation operation, the seawater flowing through the auxiliary system rises in temperature each time it cycles through a small cycle. In this way, the seawater circulation system 108 combines the circulating water having a relatively small temperature difference by mixing seawater (seawater whose temperature rises slowly) through the auxiliary system and seawater (seawater heated by the heating device) via the hot water circulation system. Can be supplied to As a result, a stepwise increase in temperature can be achieved, and the formation of the temperature layer is suppressed. Formation of the temperature layer is suppressed, and the survival of sea creatures due to the generation and stagnation of the cold water layer can be suppressed.

Moreover, the temperature of the seawater which flows into an auxiliary system is detected by the temperature detector 124 provided in the seawater circulation system 108. By controlling the auxiliary system circulation pump 117 using this detection signal, economical operation is possible by adjusting the flow rate of seawater flowing through the auxiliary system.

Moreover, the temperature detector 123 provided in the hot water circulation system 101 detects the temperature of the seawater which flows into a seawater circulation system. The heating device 103 is controlled using the detection signal of the temperature detector 123.

In this embodiment, the auxiliary system 116 can also be used as a ball cleaning system.

(Example 2).

When the heat exchanger 113 is a condenser, the ball cleaning system 116 is provided so as to connect the ball injection pipe 118 of the condenser inlet side 111 and the ball collector 119 of the condenser outlet side 112. It is a system parallel to the seawater circulation system 108, and has a ball circulation pump 117, a ball recovery device, and various valves.

The procedure of operation when an auxiliary system is used as a ball cleaning apparatus is demonstrated below.

i) Circulating water is introduced into the ball cleaning system 116.

ii) A special sponge ball is injected into the seawater circulation system 108 from the ball injection pipe 118. The sponge ball passes through the cooling tube of the condenser and cleans the inside of the cooling tube.

iii) The sponge ball is recovered from the ball collector 119. The sponge ball is injected into the seawater circulation system 108 via the ball cleaning system 116 again.

The ball cleaning system 116 has almost the same function as the auxiliary system. For example,

① point parallel to the seawater circulation system 108,

② point of introduction of seawater from the seawater circulation system 108,

(3) A ball circulation pump 117 is provided with a circulation pump, and by operating the circulation pump, the circulating water is taken in from the circulating water system outlet side 110 and injected into the circulating water system inlet side 109,

④ The flow rate in the ball cleaning system 116 is usually about 3 m / s, etc.

For this reason, in the plant provided with the ball cleaning system 116, the ball cleaning system 116 can be used as an auxiliary system.

In addition, in this embodiment, the auxiliary system 116 can also be used as a cooling system (auxiliary device cooling system) of the condenser which is an auxiliary device cooler (Example 3).

When the auxiliary system is used as the auxiliary equipment cooling system, the circulating water pump 200 (shown in dashed lines in FIG. 1) is installed outside the seawater outlet valve 115, and the plurality of cooling systems 108 (seawater circulation system) Is used as a plurality of cooling systems) flows in the same direction (from right to left in FIG. 1) as seawater flowing through the auxiliary equipment cooling system.

The auxiliary device cooling system 116 is formed in the plurality of cooling systems 108. The auxiliary device cooling system 116 branches from the inlet side 112 of the condenser 113 and joins at the outlet side 111 of the condenser 113. The auxiliary equipment cooling system 116 is a system parallel to the plurality of cabinet systems 108 and includes a heat exchanger (shown in dashed lines in FIG. 1) 122, a boosting pump 117, and the like for producing cooling water.

The auxiliary equipment cooling system 116 is a system for cooling the cooling water used for cooling the condenser by the heat exchanger 122 with seawater.

During plant operation, seawater is withdrawn from the inlet side 112 into the system by operating the booster pump 117, and heat-exchanged by the heat exchanger 122, and then waterproofed to the outlet side 111. FIG. Here, the circulating water injection point 106 is provided at the circulating water system outlet side 109, and the circulating water recovery point 107 is provided at the circulating water system inlet side 110. The functions of the auxiliary system, the auxiliary device cooling system 116, the auxiliary system circulation pump and the boosting pump 117 are almost the same.

When the boost pump 117 is operated, a circulation small cycle of the auxiliary device cooling system 116 to the plurality of cooling systems 108 to the auxiliary device cooling system 116 is formed, which stimulates the circulation of hot water, Uniformity can be attained.

In addition, it is assumed that the flow rate by the boost pump 117 is larger than the flow rate by the hot water circulation pump 102.

In the initial stage of the hot water circulation operation, at the auxiliary equipment cooling system outlet 118, the mixing temperature of the seawater from the hot water circulation system 101 and the seawater from the auxiliary equipment cooling system 116 is determined from the ratio of the flow rates flowing through the auxiliary equipment. The temperature is close to that of the seawater flowing through the cooling system 116. For this reason, the temperature rise for each cycle of the circulating water can be reduced, and the time consumed per cycle can also be shortened. Thereby, temperature rise of circulating water can be made smooth, and the uniformity of circulating water temperature can be improved further.

In Examples 1 to 3, it is preferable to provide a plurality of nozzles of the circulation water injection point 106 from the hot water circulation system 101 and the auxiliary system outlet 118 from the auxiliary equipment system 116 at arbitrary intervals. desirable. This prevents the deterioration of mixing and stirring effects downstream and the formation of a temperature layer over time, thereby realizing more effective mixing and stirring of the circulating water.

The nozzle shapes of the circulation water injection point 106 in the hot water circulation system 101 and the auxiliary system outlet 118 in the auxiliary system 116 are shown in FIG. As shown in FIG. 2A, the hot water circulation system 101 is connected to cause swirl flow in the piping of the seawater circulation system 108. As shown in FIG. 2 (b), the hot water circulation system 101 is connected so that the discharged seawater moves upward in consideration of the density difference between the seawater discharged at the circulation water injection point and the seawater flowing through the seawater circulation system. It is. By blowing downward, effective mixing and stirring are realized.

Moreover, the case where this invention is employ | adopted in the cooling system of the condenser which consists of two systems is shown in FIG. 3 (Example 4).

The seawater withdrawn by the circulating water pumps la and 1b is fed to the condenser 4a and 4b by the condenser inlet cooling water pipes 3a and 3b via the pump outlet valves 2a and 2b. The seawater that cools the turbine exhaust in the condensers 4a and 4b and heat-exchanges the water through the condenser outlet cooling water pipes 5a and 5b and is led to the waterproof path 7 and discharged to the sea.

Moreover, the condenser outlet valves 6a and 6b are disposed in the middle of the pipes 5a and 5b, and the system is isolated from the sea by the outlet valves 2a and 2b and the outlet valves 6a and 6b. Downstream of the outlet valves 2a and 2b, harvesting pipes 9a and 9b provided with harvesting valves 8a and 8b are provided. By switching the harvesting valves 8a and 8b, the cooling water can be harvested from the cooling system of any condenser.

Harvest pipes 9a and 9b join at the inlet side of the hot water circulation pump 11. The seawater discharged from the hot water circulation pump 11 flows through the hot water circulation pipes 10, 10a, and 10b through the hot water production device 12 and circulates. Seawater can be injected into piping 5a, 5b of arbitrary cycles 4a, 4b by the switching operation of hot water intake valve l4a, l4b.

When removing sea creatures using the cooling system of the condenser comprised in this way, it carries out by the following method.

First, the case where a condenser is operated in a power plant is demonstrated below. Seawater is taken in and boosted by the circulating water pumps la and 1b. Seawater is fed to the condenser 4a, 4b by the piping 3a, 3b via the outlet valve 2a, 2b. The cooling water exiting the condensers 4a and 4b is waterproofed by the waterproof passage 7 through the pipes 5a and 5b and the outlet valves 6a and 6b and discharged to the sea. At this time, the hot water circulation system having the hot water circulation pump 11, the hot water production device 12, and the plumbing facility completely closes the harvesting valves 8a and 8b and the injection valves l4a and l4b and enters the standby state.

In shifting from this state to hot water circulation,

(1) First, the cooling system of the condenser targeted for hot water circulation is stopped. Here, the case where hot water circulation is performed to the cooling system of the b system condenser is demonstrated. Usually, when the cooling system of the condenser is stopped, the cooling water is maintained in the system in consideration of the wet time at the next start. After the circulating water pump 1b is stopped, the outlet valve 2b is closed and the outlet valve 6b is closed.

(2) Then, the cooling water (sea water) in the cooling system formed between the outlet valve 2b and the outlet valve 6b is discharged. The discharge of sea water is carried out by selecting and opening various valves formed in the cooling system, for example, a vent valve or a drain valve (not shown). In addition, when the piping level of the cooling system of the condenser is higher than the intake water level and the watertight path level, the outlet valve 6b and / or the outlet valve 2b can be discharged to the watertight passage 7 or the intake side. In addition, a drain pump may be provided in the piping of the condenser cooling system, and the pump may be forcibly discharged.

(3) Next, the harvest valve 8a is opened and seawater is withdrawn from the cooling system of the a series condenser in operation. Then, the seawater is led to the hot water circulation pump 11, and the pressure is increased by the hot water circulation pump 11. Thereafter, the seawater is passed through the hot water producing apparatus 12, and the temperature is raised to a temperature at which sea creatures reach fatalities.

(4) The seawater heated up by the hot water production device 12 is introduced into the piping 5b of the cooling system of the b system condenser formed between the outlet valve 2b and the outlet valve 6b by opening the injection valve l4b. . The hot water introduced into the pipe 5b fills the pipe 3b, the pipe 5b and the condenser 4b while discharging air from the top of the condenser 4b or a vent valve (not shown) provided in the pipe.

(5) By this operation, after the cooling system of the b-type condenser formed by the outlet valve 2b and the outlet valve 6b is filled with hot water, the harvest valve 8b is opened and the harvest valve 8a is simultaneously opened. Close it. Thereafter, the flow shifts to the warm water circulation operation of the cooling system of the b system condenser.

By carrying out this operation for a certain time, it is possible to prevent the removal or attachment of sea creatures in the cooling system of the condenser.

In the present embodiment, the cooling system of the condenser consisting of two systems has been described, but it is also possible in the case of the constitution of a plurality of systems of two or more systems.

In this embodiment, the hot water production device 12 is disposed on the outlet side of the hot water circulation pump 11, but the hot water production device 12 may be provided on the inlet side of the hot water circulation pump.

In addition, although the piping and the condenser to be removed from the sea creatures are filled with hot water and the hot water is circulated, sufficient effect can be expected by maintaining the hot water for a certain time. The piping forming the condenser cooling system generally has a large diameter (about 1.5 m to 4 m). When the warm water is full, since the heat capacity of the hot water greatly exceeds the heat capacity of the pipe, and the specific surface area (= pipe surface area / volume in the pipe) is small, the temperature drop of the hot water due to heat dissipation is small. As a result, it is not necessary to circulate the hot water.

In addition, as long as seawater can pass the hot water manufacturing apparatus 12, you may remove the hot water circulation pump 11.

In addition, since hot water is injected from the outlet side of the condenser, the flow of cooling water in the condenser is reverse to the flow during normal operation. In this case, it also has the same effect as the backwashing operation performed in the cooling system of the condenser.

Moreover, as shown by the dotted line in FIG. 3, a part of seawater is withdrawn from the piping 3a, 3b to the auxiliary equipment coolers 23a, 23b via bypass pipes 22a, 22b. Then, after the heat exchange in the auxiliary equipment coolers 23a and 23b, the flow returns to the pipes 5a and 5b via the bypass pipes 22a and 22b again. Thereby, the cooling system of the auxiliary equipment cooler together with the cooling system of the condenser can simultaneously remove sea creatures.

In addition, as shown by the dashed-dotted line in FIG. 3, when hot water is harvested by a pipe and a condenser to be removed by sea creatures, the seawater is directly taken from the sea to the pump 24 and supplied to the hot water circulation pump 11. It may be. In this embodiment, the procedure of (1) and (2) in the case of the transition to the standby state when the condenser is operating and the hot water circulation is the same as in the fourth embodiment.

Next, the valves 8a and l4a are closed, the pump 24 is started, seawater is taken out, and supplied to the hot water circulation pump 11 via the valve 25. The pressure is increased by the hot water circulation pump 11, the temperature is increased by the hot water production device 12, and hot water is injected into the pipe 5b via the valve 14b. After this operation fills the piping and the condenser to be removed by sea water with hot water, the valve 25 is closed and the valve 8b is opened to provide hot water circulation. To fulfill.

In this embodiment, since seawater, which is hot water, is directly taken from the sea by a pump, it is also possible to adopt a cooling system of a condenser composed of one system.

In this embodiment, the direction of seawater flowing through the hot water circulation pipe 10 can be changed by changing the installation direction of the hot water circulation pump 11. That is, the cooling water at the outlet side of the condenser can be injected as hot water to the inlet side of the condenser by the hot water circulation pump 11. Then, the operation method changes as the circulating water flowing in the hot water circulation pipe 10 flows in the direction opposite to the fourth embodiment (from right to left in FIG. 3) (Example 5).

Moreover, it is preferable that the hot water circulation pump 11 and the hot water manufacturing apparatus 12 formed in the hot water circulation pipe 10 are formed in the order with respect to the direction of the seawater which flows through the hot water circulation pipe 10. That is, in this embodiment, the seawater flows from the right side to the left side in FIG. 3, and the hot water circulation pump 11 and the hot water production apparatus 12 are formed in order from the right side.

The order of (1) and (2) in the standby state when the condenser is in operation and in the case of shifting to the warm water circulation is the same as in the fourth embodiment.

(3-1) Next, the intake valve l4a is opened and seawater is taken out from the cooling system of the a system condenser in the operating state. Then, the seawater is led to the warm water circulation jump 11, and the pressure is increased by the warm water circulation pump 11. Thereafter, the seawater is passed through the hot water producing apparatus 12, and the temperature is raised to a temperature at which sea creatures reach fatalities.

(4-1) The seawater heated up by the hot water production device 12 is opened to the piping 3b of the cooling system of the b-type condenser formed between the outlet valve 2b and the outlet valve 6b by opening the water injection valve 8b. Is introduced.

(5-1) By this operation, after the cooling system of the b system condenser is filled with warm water, the intake valve l4b is opened and the intake valve l4a is closed.

In this embodiment, the cooling water on the outlet side of the condenser can be used as the circulating water.

The cooling water on the outlet side of the condenser heat-exchanged and condensed with the turbine exhaust in the condenser has a high temperature of about 5 to 7 ° C relative to the cooling water on the inlet side of the condenser. Therefore, rather than raising the cooling water on the inlet side, the temperature raising value of the cooling water on the outlet side can be reduced, and the capacity of the hot water producing apparatus 12 can be reduced.

In this embodiment, since the cooling water on the outlet side of the condenser is harvested, the entire amount of seawater used in the a condenser can be harvested without affecting the cooling capacity of the a condenser in operation.

In addition, with respect to the embodiment shown in FIG. 3, the cooling water at the outlet side of the condenser in the operating state may be injected into the pipes 5a and 5b via the hot water circulation pump 11 and the hot water producing apparatus 12. (See Example 6, FIG. 4).

The hot water producing apparatus 12 is disposed on the outlet side of the hot water circulation pump 11. The hot water circulation pipe 10 and the pipes 5a and 5b are connected via the valves 8a and 8b and the valves 4a and 4b.

In addition, pipes 10a and 10b having valves 4a and 4b, valves 8a and 8b and harvest pipes 9a and 9b are connected by pipes 2la and 21b having valves 7a and 7b. . In addition, the pipes 2la and 2Ib branch from the pipes between the valves 4a and 1b and the valves 8a and 8b. The other configuration is the same as that of FIG.

When removing sea creatures using the cooling system of the condenser of such a structure, it carries out by the following method.

The procedure of (1) and (2) in the case of shifting to the standby state and the hot water circulation when the condenser is operating is the same as in the fourth embodiment.

(3-2) Next, the seawater is taken into the pipe 10 from the cooling system of the multiplier a in the operating state by opening the valve l4a and closing the valve l8a and the valve l7b. Then, the seawater is guided to the hot water circulation pump 11 via the valve 17a, and is boosted by the hot water circulation pump 11. Thereafter, the seawater is passed through the hot water producing apparatus 12, and the temperature is raised to a temperature at which sea creatures reach fatalities.

(4-2) The b system formed by the outlet valve 2b and the outlet valve 6b by passing the pipe 10 and opening the valve 10b and the valve 14b through the pipe 10 and opening the valve 10b. It is introduced into the piping 5b of the cooling system of the condenser.

(5-2) By this operation, the hot water introduced into the pipe 5b fills the pipe 3b, the pipe 5b, and the condenser 4b. After the cooling system of the b system condenser formed by the outlet valve 2b and the outlet valve 6b is filled with hot water, the valve 8b is opened, and the valve l4a and the valve l7a are closed. This hot water is introduced into the hot water circulation pump 11 again through the valve 8b and the pipe 9b, and the flow of water is shifted to the hot water circulation operation of the cooling system of the b system condenser.

In this embodiment, hot water is injected from the outlet side of the condenser. Since the flow of the cooling water in the condenser is reversed from the flow during normal operation, it has the same effect as the backwashing operation performed in the condenser cooling system. And since the cooling water (higher about 5-7 degreeC than the cooling water at the inlet side) of the exit side of the condenser is used as the circulating water, the capacity of the hot water producing apparatus 12 can be reduced.

Moreover, the distance of piping becomes long from the circulation water pumps la and 1b to the valves 6a and 6b. In this embodiment, when the sea creatures are removed by maintaining hot water (when the hot water circulation is not performed), the pipes 9a and 9b including the valves 8a and 8b can be deleted. Therefore, since the equipment is configured near the valves 6a and 6b, there is no need to provide a pipe communicating with the inlet side of the condenser, and the distance between the pipes can be shortened, so that the equipment cost can be reduced.

Moreover, the direction of the seawater which flows through the hot water circulation pipe 10 can be changed by changing the installation direction of the hot water circulation pump 11 (refer FIG. 5). That is, the cooling water at the outlet side of the condenser can be injected as hot water to the inlet side of the condenser by the hot water circulation pump 11. Thus, a description will be given of the fact that the operation method changes as the circulating water flowing in the hot water circulation pipe 10 flows in the opposite direction to the sixth embodiment (Example 7).

This embodiment is characterized in that the cooling water at the inlet side of the condenser in the operating state is injected into the pipe at the inlet side of the condenser via the hot water circulation pump 11 and the hot water producing apparatus 12.

When removing sea creatures using the cooling system of the condenser of such a structure, it carries out by the following method.

The order of (1) and (2) in the standby state when the condenser is in operation and in the case of shifting to the warm water circulation is the same as in the fourth embodiment.

(3-3) Next, the valve 8a is opened, the valve l8b and the valve l7b are closed to pass through the pipe 9a, and the cooling system of the a system condenser in a normal state via the valve l7a. Sea water is taken from. Then, the seawater is led to the hot water circulation pump 11, and the pressure is increased by the hot water circulation pump 11. Thereafter, the seawater is passed through the hot water producing apparatus 12, and the temperature is raised to a temperature at which sea creatures reach fatalities.

(4-3) The seawater heated up in the hot water production device 12 passes through the pipe 9b to open the valve 18b and the valve 8b so as to be formed between the outlet valve 2b and the outlet valve 6b. It is introduced into the piping 3b of the cooling system of the system condenser.

(5-3) By this operation, after the cooling system of the b-type condenser is filled with hot water, the valve l4b is opened and the valve 8a and the valve l7a are closed to circulate the hot water of the cooling system of the b-type condenser. Shift to driving.

Also in this embodiment, when sea creatures are removed by maintaining hot water without performing hot water circulation, the pipes 10a and 10b including the valves l4a and l4b can be deleted. Therefore, since the equipment can be configured in the vicinity of the outlet valves 2a and 2b, it is not necessary to provide a pipe communicating with the outlet side of the condenser and the equipment cost can be reduced.

In this embodiment, the cooling water at the outlet side of the condenser in the operating state is guided to the hot water producing apparatus 12 by the discharge pressure of the circulating water pumps la and 1b, and is supplied to the circulating water pump of the system to remove the sea creatures. do. And hot water circulation is performed by this circulation water pump (refer Example 8, FIG. 6).

At the inlet side of the circulating water pumps la and 1b, valves 2a and 2b (partitioning mechanisms for closing the intake passage) are provided. The circulating water pumps la and 1b and the condensers 4a and 4b are connected by pipes 3a and 3b. The piping 5a, 5b connected to the outlet side of the condenser 4a, 4b has the outlet valve 6a, 6b, and is connected with the waterproof path 7. The pipe 9 branched again from the pipes 9a and 9b branched from the pipes 5a and 5b is connected to the inlet side of the hot water producing apparatus 12. The outlet side of the hot water production device 12 and the inlet side of the circulating water pumps la and 1b are connected by pipes 10, 10a and 10b.

The order of (1) and (2) in the standby state when the condenser is operating and the case of shifting to the warm water circulation is the same as in the fourth embodiment.

(3-4) Next, the valve 8a is opened and the seawater flowing through the cooling system of the a system condenser is introduced into the hot water producing apparatus 12. Then, the valve 14b is opened to supply hot water to the cooling system of the b-type condenser.

(4-4) After the cooling system of the b system condenser is filled with hot water, the valve 8a is closed and the valve 8b is opened to stop the supply of hot water.

(5-4) After the system for circulating the hot water is formed, the circulating water pump 1b is started to circulate the hot water with the circulating water pump 1b.

In this embodiment, since the hot water circulation is performed by the circulation water pump 1b, the hot water circulation pump can be eliminated, so that the equipment cost can be reduced.

As described above, by separating and separating the fluid flow path such as the equipment and piping that removes sea creatures by hot water from the seawater by using a partitioning mechanism such as a valve, the water, the piping, the single system, and the multiple systems, Elimination of creatures is possible.

In addition, when the center position of equipment piping or the like is lower than the sea level, it is impossible to discharge cold water by natural gradient. In this case, hot water can be injected by omitting the cold water drainage operation.

Example 9 in which a means for forming a free liquid level in a system is provided (see FIG. 7).

A vent line 32 having a vent valve 27 is provided at the top of the water chamber 31 of the condenser 4b corresponding to the highest position in the vertical direction in the system. The pipe 33 branched from the upstream side of the vent valve 27 has a vacuum release valve 28. The pipe 33 has a pressure line 38 for pressurizing the system as needed. The pressurization line 38 has a pressurizer 30 and a stop valve 29.

When the coolant remaining in the system is discharged before the hot water circulation starts, the vent valve 27 or the vacuum breaker valve 28 is opened to induce air in the system, and the coolant is discharged using gravity. In addition, the vent valve 27 and the vacuum release valve 28 may be closed, the stop valve 29 may be opened, and the pressure of the pressurizer 30 may be applied to the water chamber 31 to discharge the cooling water. In this case, the discharge time can be shortened.

After the drainage is completed, the valve 8a is opened to introduce cooling water from the other shaft.

The warm water is heated in the warm water producing apparatus 12, and the system four is filled with warm water. At this time, the air in the system is discharged via these valves by opening the vent valve 27 and / or the vacuum release valve 28 and closing the stop valve 29. The blowout point of the vent line 32 is at the highest position in the vertical direction in the system so that air in the system can be completely discharged. After the soaking with hot water is completed, the valve 8a is closed and the supply of seawater is stopped.

If the blowout point of the vent line 32 is not at the highest position in the vertical direction in the system, the siphon is formed without installing the vacuum release valve 28 and no free liquid level is formed in the water chamber 31. In this state, when the hot water circulation pump 11 is started, the effective pump suction pressure cannot be secured, so the hot water circulation pump 11 generates cavitation. For this reason, it becomes difficult to circulate the hot water in a system. By opening the vacuum release valve 28 and setting the water chamber 31 to a negative pressure, air can be sucked, and such a situation can be avoided. In the water chamber 31, an atmospheric pressure free liquid surface 30 is formed on the upper surface of the water, and an effective pump suction pressure can be ensured. In order to actively secure the pump suction pressure, after the free liquid surface 30 is formed, the vent valve 27 and the vacuum release valve 28 are closed and the stop valve 29 is opened to circulate the water chamber 31 and the hot water. The system may be pressurized.

Next, when the hot water in the system is circulated, the temperature of the hot water due to heat dissipation from the surface of the equipment, piping and the like decreases, and the volume of the hot water shrinks. It is necessary to absorb this contraction. For example, when the temperature of hot water falls 1 degreeC, the volume of hot water will shrink | contract 5 m <3>. If the water chamber 31 does not communicate with air (outside air) or communicates with the pressurizer 30, the inside of the water chamber 31 becomes a negative pressure. Thereby, the hot water circulation pump 11 may generate cavitation. Therefore, during the hot water circulation, it is necessary to open the vent valve 27 or the vacuum release valve 28 to form a free liquid surface at atmospheric pressure, or to open the stop valve 29 to pressurize the water chamber 31.

Moreover, the bypass passage 39 which consists of piping narrower than the piping 5b is formed so that the exit valve 6b may be bypassed. And the water temperature detection means 37 is provided downstream of the outlet valve 6b. The bypass flow passage 39 is formed to discharge used hot water out of the system.

Hot water discharged from power plants requires attention in terms of protection of the marine environment. The rate of discharge of used hot water into the sea is limited in this respect. After the hot water circulation is finished, the hot water circulation pump 11 is first stopped. Then, the harvest valve 8a is slightly opened, and the coolant is prepared to be fed into the system. At this time, if the outlet valve 6b is fully opened, the rate of hot water discharged is increased, cavitation occurs at the harvest valve 8a, and there is a possibility of damaging the harvest valve 8a. In order to solve this problem, hot water is discharged using the bypass flow passage 39 in a state where the outlet valve 6b is closed.

Since the bypass flow path 39 has a small flow path area, the bypass flow path 39 becomes a resistor, and the speed of the hot water to be drained can be reduced.

An orifice may be provided in the bypass flow passage 39 to share the pressure applied to the bypass flow passage.

By providing the bypass flow passage 39, the cavitation of the harvest valve 8a can be prevented and the rate of hot water discharged can be reduced, thereby protecting the marine environment.

In addition, when discharging hot water, the flow rate discharged can be finely adjusted by closing the vent valve 27 and the vacuum release valve 28.

The end of discharging the hot water is judged by a signal from the water temperature detecting means 37. Based on this signal, the harvest valve 8a is closed, and then the harvest valve 8b and the injection valve 14b are closed.

Moreover, the liquid level detection means 36 is provided in the piping which comprises a seawater circulation system.

Drain the system's cold water before filling the system with hot water. At this time, the amount of cold water remaining in the system is estimated by detecting the water level of the liquid level formed in the pipe 3a and / or the pipe 5b. Thereby, the timing to end drainage can be set suitably.

1 is a representative configuration diagram showing a cooling installation of a heat exchanger using sea water.

2 is a configuration diagram showing a portion where the seawater circulation system and the hot water circulation system join.

3 is a block diagram showing a cooling system for two heat exchangers.

4 is a block diagram showing a cooling system for a two-system heat exchanger having a bypass pipe.

5 is a configuration diagram showing a cooling system of two heat exchangers having a bypass pipe and having reversed the direction of seawater flowing in a hot water circulation system.

6 is a configuration diagram showing a cooling system for two heat exchangers in which a hot water circulation pump is omitted.

7 is a configuration diagram showing a cooling installation of a heat exchanger using sea water having a vent valve and the like.

Explanation of symbols for the main parts of the drawings

Claims (4)

In the operation method of the seawater cooling system in the turbine installation of the power plant composed of a plurality of units having a plurality of circulating water pump, For seawater cooling system of specific unit which stopped power generation, Discharging the remaining coolant in the seawater cooling system, supplying the cooling water via a harvesting pipe connected to other units during power generation, and boosting the pump to the harvesting pipe to a lethal temperature equivalent to sea creatures. Heating the cooling water to make hot water, and then introducing hot water into the seawater cooling system of the sea creature removal target unit, and filling the inside of the seawater cooling system with hot water and maintaining it for a considerable time until the death of the sea creatures. And a step of removing sea creatures in the seawater cooling system. In the operation method of the seawater cooling system in the turbine installation of the power plant composed of a plurality of units having a condenser and a circulating water pump, For seawater cooling system of specific unit which stopped power generation, Discharging the remaining coolant in the seawater cooling system, supplying the cooling water via a harvesting pipe connected to other units during power generation, and boosting the pump to the harvesting pipe to a lethal temperature equivalent to sea creatures. The process of heating the cooling water to hot water, then inducing hot water to the seawater cooling system of the sea creature removal target unit, and filling the inside of the seawater cooling system with hot water and pumping it over a considerable time until the death of the sea creatures. And a step of circulating hot water to remove sea organisms in the seawater cooling system. The method according to claim 1 or 2, wherein the hot water remaining in the seawater cooling system is discharged after the seawater cooling system is filled with warm water and the sea creatures are killed. And supplying the cooling water to replace the hot water with the cooling water. The method of operating a seawater cooling system according to claim 1 or 2, wherein the hot water in the seawater cooling system is gradually discharged through the bypass passage.