JPS6240604B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a steam recovery device for condensing used steam or surplus steam, recovering it as condensate, and reusing it as a water source for steam generation.

For example, in nuclear power plants, steam obtained from in-house boilers is used to heat various equipment and equipment, and the steam used in these equipment is recovered as condensate by steam recovery equipment. , which is again used as a water source for steam generation. This circulatory system is as shown in FIG. That is, the steam generated in the boiler a is used in the steam utilization equipment b, and the used steam and condensate pass through the trap c, flow through the condensate return pipe d, and are sent to the steam recovery device e. This steam recovery device e has conventionally been constructed as shown in FIG. 2, for example. In other words, f is a flash tank, and the saturated water that is depressurized and flashed in tank f is transferred to trap g.
The condensate accumulated in the receiver tank h is sent by a condensate transfer pump i, and is returned to the boiler water supply tank k through a condensate transfer pipe j. There is.

However, in such a conventional steam recovery device e, since the condensate accumulated in the flash tank f must be transferred to the receiver tank h by gravity,
It is necessary to install the flash tank f at a position considerably higher than the receiver tank h, and the condensate transfer pump i, which is a centrifugal pump, must be installed at a position considerably lower than the receiver tank h in order to secure its forced water head. There is a need. Therefore, the vertical dimensions of the steam recovery device e are quite large, and a considerable amount of space is required to install the steam recovery device e inside the building. Even more inconveniently, even though the condensate return pipe d needs to be installed with a downward slope on the downstream side because steam and condensate flow inside it, the steam recovery pipe d is If the vertical height difference of the device e is large, it becomes difficult to secure the slope of the condensate return pipe d, and this becomes more noticeable as the condensate return pipe d is routed longer, and has become a major obstacle in plant design.

This invention was made based on the above circumstances, and its purpose is to facilitate securing the slope of the condensate return pipe, reduce the vertical dimensions of the steam recovery device, and reduce the installation space within the building. The purpose is to provide a steam recovery device that can reduce the amount of water used.

A first embodiment of the present invention will be described below with reference to FIG. In the figure, 1 is a flash receiver tank, and this tank 1 is connected to the steam utilization equipment b described above via a condensate return pipe d. 2 is a cooler that cools the saturated water in the tank 1.
Further, the tank 1 is provided with a vertical axial flow pump as an example of the water pump 3. This water pump 3 is of a type in which the impeller rotates while being submerged in water, and is a self-contained pump that pumps condensate in the tank 1 without causing cavitation. Other types of pumps may also be used. The discharge side of this water pump 3 is led to a boiler water supply tank k via a condensate transfer pipe j. Further, 4 is a level switch, which detects that the water level in the tank 1 has reached a predetermined value and operates the water pump 3 to transfer the condensate in the tank 1 to the boiler water supply tank k. It is starting to be sent to

In the device of this embodiment configured as described above, the return condensate from the trap c enters the flash receiver tank 1 through the condensate return pipe d as saturated water at a pressure of several kg/ ^cm2 , and the tank The saturated water is depressurized and flushed in the tank 1, and the saturated water is cooled in the cooler 2 and stored at the bottom of the tank as condensed water. When a certain amount of condensate has accumulated, the level switch 4 detects this and operates the pump 3 to send the condensate to the transfer pipe j and supply it to the boiler water supply tank k. The water in the water supply tank k is then sent to the boiler a, where it is vaporized and used again.

According to the steam recovery device of this embodiment, the condensate obtained in the flash receiver tank 1 is stored in this tank 1 as it is, and the condensate is pumped up by the pump 3 and then Since the water is sent to the water transfer pipe j, the entire device can be downsized, and in particular, the vertical dimensions can be significantly reduced. Therefore, it is not only easy to secure space in the building for installing the steam recovery device, but also the vertical dimensions of the steam recovery device can be shortened, so even if the condensate return pipe d has a long piping route. Even if the condensate return pipe d has a gradient, it is extremely easy to ensure the slope of the condensate return pipe d, and the degree of freedom in designing the piping and equipment arrangement is greatly improved when designing the plant.

As described above in detail, the steam recovery device according to the present invention is a steam recovery device that condenses steam used in steam utilization equipment and returns it to a boiler feed water tank. An integrated flash receiver tank that is connected to steam utilization equipment and obtains and stores condensate by reducing the internal pressure, and an immersion pump that pumps up the condensate in this tank and sends it to the boiler water supply tank. , comprising a level switch that detects that the water level in the tank has reached a predetermined value and operates the water pump, and a cooler that is attached to the tank and cools the condensate in the tank. That is.

Therefore, it is no longer necessary to ensure a large vertical dimension to take into account the natural flow from the flash tank to the receiver tank and the forced water head from the receiver tank to the condensate transfer pump, as in the past, and the vertical dimension of the equipment is reduced. can be significantly shortened. This greatly improves the degree of freedom in plant design, such as making it easier to ensure the slope of the condensate return pipe. Furthermore, since the water pump is of the immersion type and its emperor is immersed in compound water, concerns about cavitation are effectively eliminated. Furthermore, the condensate can be cooled by a cooler, which has great effects.

[Brief explanation of the drawing]

Figure 1 is a piping diagram of steam circulation equipment in a nuclear power plant, Figure 2 is a configuration diagram of a conventional steam recovery device,
FIG. 3 is a longitudinal sectional view of a steam recovery device showing a first embodiment of the present invention. 1... Flush receiver tank, 3... Lifting pump, 4... Level switch.

Claims (1)

[Claims] 1 In a steam recovery device that condenses the steam used in steam utilization equipment and returns it to the boiler feed water tank, it is connected to the steam utilization equipment via a downward slope condensate return pipe and recovers the steam by reducing the internal pressure. An integrated flash receiver tank that obtains and stores water, an immersion pump that pumps up the condensate in this tank and sends it to the boiler water supply tank, and a water level in the tank that reaches a predetermined value. A steam recovery device comprising: a level switch that detects this and operates the water pump; and a cooler that is attached to the tank and cools condensate in the tank.