JPH01190906A - Cooling seawater device for machinery - Google Patents

Abstract

PURPOSE:To prevent the reduction of the cooling faculty and erosion of piping and equipment by independently connecting a plurality of seawater pumps, inlet pipes, heat exchangers, and outlet pipes and installing a communication pipe having a communication valve for connecting a plurality of inlet pipes. CONSTITUTION:The pump outlet pipes 7-9 of the seawater pumps 1-3 are directly connected with the inlet pipes 10-12, and the outlet pipes 19-21 are introduced into a water discharge port 22. A communication pipe 25 having a communication valve 23 permits the communication between the inlet pipe 10 and the inlet pipe 11. A communication pipe 26 having a communication valve 24 permits the communication between the inlet pipe 11 and the inlet pipe 12. In order to prevent the operation states of the seawater pumps 1-3 and heat exchangers 16-18 which are arranged in parallel from being influenced each other, the operation of a seawater device for cooling the machineries is not suspended, and all the positions can be made clean. Therefore, the reduction of the cooling faculty due to the adhesion of seawater articles and the erosion of piping and machineries can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an equipment cooling seawater system for a steam turbine plant, and more particularly to an equipment cooling seawater system suitable for cleaning during an inversion.

[Conventional technology]

The conventional device is published in the magazine Thermal and Nuclear Power Generation Vol.

33 (Published by Thermal and Nuclear Power Generation Technology Association) Na2
As described on pages 133 to 186, the outlet pipes of a plurality of pumps arranged in parallel were joined to the inlet main pipe and branched to the inlet pipe of the heat exchanger. In addition, the outlet pipes of multiple heat exchangers were also merged into the outlet main pipe and introduced into the water outlet, so the equipment cooling seawater system had to be stopped in order to clean the inlet and outlet main pipes. However, cleaning during operation was not considered.

[Problem to be solved by the invention]

The above conventional technology does not take into account the fact that when cleaning is required due to marine life adhering to the inner surface of the piping, cleaning can be done without stopping the equipment cooling seawater system, and when cleaning is performed, equipment cooling is required. It was necessary to shut down the seawater equipment.

Here, the prior art will be explained with reference to FIG. 2.

FIG. 2 shows a schematic configuration of a conventional equipment cooling seawater system for a steam turbine plant. Seawater pump 1, 2.3
The seawater supplied by is led to the pump outlet pipe 7,8°9 with pump outlet valves 4,5.6 and after joining the inlet main pipe 27, the inlet pipe with inlet valves 13.14.15. 10
, 11.12 and introduced into heat exchangers 16.17.18. The seawater introduced into the heat exchangers 16 to 18 exchanges heat with freshwater and freshwater circulating through an equipment cooling water system (not shown), so that the seawater is heated and the freshwater is cooled. Seawater discharged from heat exchangers 16-18.

The water is guided to outlet pipes 19 to 21 having outlet valves 28 to 3o, joins the outlet main pipe 31, and is discharged to the water outlet 22.

The above-mentioned equipment cooling water system cools a plurality of equipments constituting the plant by using fresh water circulating within the equipment.

Some of these devices need to be cooled not only during normal plant operation but also during periodic plant inspections. Therefore, when the operation of the equipment cooling seawater system is stopped, seawater is not supplied to the heat exchangers 16 to 18, so
Since the fresh water in the equipment cooling water system (not shown) is not cooled, and the plant component equipment is not cooled, the operating temperature of the component equipment increases, resulting in damage to the equipment.

Therefore, the equipment cooling seawater system needs to be operated at all times.

On the other hand, since seawater flows through the equipment constituting the single-equipment cooling seawater system, sea creatures such as shellfish contained in the seawater may attach and grow. The adhesion of these marine organisms increases the pipe resistance and reduces the seawater flow rate.
Marine fouling on heat exchangers 16-18 reduces heat exchange capacity. Therefore, if a large amount of sea life adheres to the equipment, the required capacity of the equipment cooling seawater system will not be satisfied, so it is necessary to remove and clean the adhered sea life.

However, in the conventional technology, the inlet valve 13 and the outlet valve 28 are closed;
Or, close the inlet valve 14 and outlet valve 29, or close the inlet valve 15.
and the outlet valve 30 respectively, the heat exchanger 1
6, 17, 18 was isolated and the equipment cooling seawater system was operated at partial load.

It was possible to clean the heat exchangers 16 to 18, but in order to clean the inlet main pipe 27 and the outlet main pipe 31.

There was a problem in that the equipment cooling seawater system had to be stopped, so cleaning could not be done while the equipment was in operation.

An object of the present invention is to provide a one-equipment cooling seawater system that can be cleaned during operation.

[Means to solve the problem]

The above purpose is to connect the pump outlet pipes 7, 8, 9 directly to the inlet pipe 10°11. pump outlet pipes that lead to the water discharge port 22 and are arranged in parallel;
Alternatively, this can be achieved by providing piping with valves connecting the inlet pipes to each other.

[Effect]

Pump outlet pipes 7, 8.9 and inlet pipes 10°, 11.9, respectively.
12 and introducing the outlet pipes 19, 20° 21 into the water outlet 22, since the operating conditions of the seawater pumps, heat exchangers, etc. installed in parallel do not affect each other, the equipment cooling seawater system All areas can be cleaned without stopping. Furthermore, by providing the connecting pipes 25 and 26 with valves, it becomes possible to independently operate the seawater pumps and heat exchangers installed in parallel, and the seawater pumps and heat exchangers that are installed in parallel can be operated independently. Heat exchange can be freely selected.

〔Example〕

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

The seawater supplied by the seawater pumps 1, 2.3 enters the pump outlet pipe 7° 8.9 with pump outlet valves 4, 5.6 and the inlet pipe 10.11.12 with inlet valves 13, 14, 15. and introduced into heat exchangers 16, 17 and 18. In the heat exchangers 16 to 18, the seawater that has undergone heat exchange with the fresh water circulating through the equipment cooling water system (not shown) flows through the outlet pipes 19 and 2.
0.21 and is discharged to the water outlet 22. Communication valve 2
3 connects the pump outlet pipe 7 or inlet pipe 10 with the pump outlet pipe 8 or inlet pipe 11. The communication pipe 26 with the communication valve 24 is connected to the pump outlet pipe 8,
Alternatively, for convenience, a series of seawater pumps 1, pump outlet valves 4. Pump outlet pipe 7, inlet pipe 10, inlet valve 13, heat exchanger 16. The outlet pipe 19 will be collectively referred to as the A series, and hereinafter, a series of devices connected to the seawater pump 2 and a series of devices connected to the seawater pump 3 will be collectively referred to as the B series and C series, respectively. Each of the A, B, and C trains has a capacity of 50% of the processing capacity required for the equipment cooling seawater system, and one train is kept as a reserve.

During normal plant operation, if two of the A, B, and C series are in operation, they have sufficient functionality as the equipment cooling seawater system. In addition, three of the heat exchangers are in operation and one is stopped, and the inlet valve of the inlet pipe connected to the stopped heat exchanger is fully closed.

Here, since the communication valves 23 and 24 are open, the two operating seawater pumps and the heat exchanger stand are A and B, respectively.
, C There is no problem in the operation of the equipment cooling seawater system in any combination in the three-unit row, and by opening the communication valves 23 and 24,
If a seawater pump that is in operation stops due to a malfunction or other reason, the stopped seawater pump will start to ensure the required seawater flow rate.

On the other hand, if marine life adheres to the inner surface of the piping, etc. and cleaning becomes necessary, the communication valve 23 is closed and step B is performed.

Operate C series and clean A series or connect valve 23.2
Close 4, operate A and C series, clean B series, or
By closing the communication valve 24, operating the A and B series, and cleaning the C series, all cleaning can be done without stopping the equipment cooling seawater system.

On the other hand, during regular plant inspections, the heat load on the equipment cooling seawater system (not shown) decreases, so the heat load on the equipment cooling seawater system also decreases, resulting in one or two operating trains, but as mentioned above, By opening and closing the communication valves 23 and 24, the A, B, and C series can be easily operated independently or in combination, making it possible to perform cleaning without stopping the equipment cooling seawater system. Sometimes, when only one train can be operated, if the A train is operating, the connecting valve 24
By closing the inlet valve 14, the seawater pump 2 can be operated as a backup device for the seawater pump 1.
The reliability is improved, and the outlet pipe 2 is connected to the C series and the inlet valve 14.
It is possible to clean up to 0. This operation is effective for all A, B, and C series operations.

According to this embodiment, cleaning can be performed without stopping the equipment cooling seawater system.

〔Effect of the invention〕

According to the present invention, cleaning can be performed without stopping the equipment cooling seawater system, which is effective in preventing a decrease in cooling capacity due to adhesion of seawater and corrosion of piping, equipment, etc.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of an embodiment of the present invention, and FIG. 2 is a system diagram of a conventional technique.

Claims (1)

[Scope of Claims] 1. A plurality of seawater pumps arranged in parallel, an inlet pipe that leads the seawater supplied by the seawater pumps to a plurality of heat exchangers arranged in parallel, and discharged water from the heat exchangers. In an equipment cooling seawater system comprising an outlet pipe that guides seawater to a water outlet, the seawater pump includes a plurality of the seawater pumps, the inlet pipe, the heat exchanger,
An apparatus cooling seawater system characterized in that a communication pipe is provided which independently connects the and outlet pipes to each other and has a communication valve that connects the plurality of inlet pipes.