JPS6025639B2 - condensate recovery pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a condensate recovery pump that pumps condensate generated in steam-using equipment to a boiler or the like, and particularly to a pump that can discharge non-condensable gases such as air to the atmosphere.

Conventionally, as a condensate recovery pump, a pump that is a combination of a centrifugal pump and an ejector pump is known and in use.

Air trapping is a serious problem in the above types of pumps, and volute pumps are particularly susceptible to air trapping, so it is necessary to completely separate and eliminate non-condensable gases such as air immediately before the volute pump. .

The present invention eliminates non-condensable gas such as air sucked into the pump before it reaches the centrifugal pump in a combination pump of a centrifugal pump and an ejector pump, eliminates problems caused by air trapping, and can be used in a vacuum system. The purpose of the present invention is to provide a condensate recovery pump that does not cause air trapping and always operates safely.

The following description will be made based on the embodiment shown in FIG. 1 is a centrifugal pump driven by an electric motor (not shown).

A circulation passage 2 connects the discharge port 3 and the suction port 4 of the centrifugal pump 1.

An ejector member 5 is arranged in the circulation passage 2.

The ejector member 5 consists of a nozzle 6, a jet part 7, and a diffuser 8, and the jet part 7 lowers the pressure due to the jet from the nozzle 6, and sucks the surrounding fluid. Reference numeral 15 denotes an inflow passage suitable for the jet section 7, which is connected to steam-using equipment (not shown) or the like.

9 is a circulation passage 2 from the discharge port 3 of the pump 1 to the nozzle 6
It is connected to a boiler (not shown), etc., through a pressure feeding passage branched from the pipe.

10 is a primary pressure regulating valve that maintains the ejection pressure of the jet ejected from the nozzle 6 in a constant state.

Reference numeral 11 denotes a steam/water separation tank disposed in the circulation passage 2 from the diffuser 5 of the ejector member 5 to the suction port 4 of the pump, and an exhaust passage 1 in the upper part of the tank 1 to allow the inside of the tank 1 to flow into the atmosphere.
2 is provided.

The exhaust passage 12 has an electrically operated valve 1 such as an electric valve or a solenoid valve.
The electrically operated valve 13 is electrically connected to an electrode level switch 14 provided in the tank 11 to open and close the exhaust passage 12 according to the liquid level in the tank 11.

That is, when the electrodes A and B of the level switch 14 are adjusted below the water surface, the electrically operated valve 13 opens and pushes out the air, etc. in the tank 11, and after expelling the air, the water level in the tank 11 recovers and the electrodes A, When C is introduced below the water surface, the electrically operated valve 13 closes. Further, this level switch 14 is a well-known general-purpose one, and a detailed explanation and explanation of the control circuit will be omitted. In addition, instead of the electric on-off valve means consisting of the electrically operated valve 13 and the bell switch 14, a mechanical on-off valve means as shown in FIG. A non-condensable gas such as air may be exhausted.

Figure 2 shows a float type air vent valve, 21 is the valve body,
22 is an inlet following the upper part of the tank 11, 23 is a float placed in the empty space 24 in the valve body 21, and 25 is the empty space 24.
The valve □, 26, which communicates the upper part of the valve to the atmosphere, is the empty space 2 of the valve port 25.
4 side ends are formed, and the float 23 is a valve seat that directly oxidizes.

According to the above configuration, non-condensable gases such as air mixed in condensate water can be separated and removed immediately before the swirl pump 1, which tends to cause trouble due to air trapping, and the swirl pump 1 can be operated safely. can. In addition, the section from the diffuser 8 where the air-water separation tank 11 is arranged to the suction port 4 of the pump 1 is a section where the pressure is constantly increased due to the pressure increasing action of the diffuser S, and the pressure difference with the atmosphere is used to remove air, etc. Non-condensable gas can be easily discharged.

Therefore, even when the inflow passage 15 side is below atmospheric pressure and air etc. mixed in the condensate cannot be removed from the inflow passage 15 side to the atmosphere, as in the case of suctioning condensate from a vacuum system, according to this embodiment, Air, etc. can be completely removed before reaching the centrifugal pump 1, and safe operation of the pump can be guaranteed. still,
Although the level switch 14 in FIG. 1 is of the electrode type, all general-purpose types such as a float type and a photoelectric type are applicable.

As described above, according to the present invention, non-condensable gas such as air sucked into the pump is removed before it reaches the centrifugal pump, eliminating the trouble caused by air trapping, and eliminating air trapping even when used in a vacuum system. We can provide a condensate recovery pump that operates safely without any problems.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the basis of a condensate recovery pump according to an embodiment, and FIG. 2 is a schematic diagram of a float-type air bleed valve. 1 is a centrifugal pump, 2 is a circulation passage, 3 is a discharge port, 4 is a suction port, 5 is an ejector member, 7 is a jet section, 9 is a pressure feeding passage, 1
1 is a steam/water separation tank, 12 is an exhaust passage, 13 is an electrically operated valve, 14 is a bell switch, and 15 is an inflow passage. Mai Figure 1 Figure 2

Claims (1)

[Claims] 1. A centrifugal pump operated by an electric motor, a circulation passage connecting a discharge port and a suction port of the pump, an ejector member disposed in the circulation passage, and an ejector member disposed from the discharge port. a pressure feeding passage branching from the circulation passage midway, an inflow passage opening to the jet portion of the ejector member, and a steam/water separation tank disposed on the circulation passage from the ejector member to the suction port;
an exhaust passage that opens the upper part of the air-water separation tank to the atmosphere;
a condensate recovery pump comprising a valve means for opening and closing the exhaust passage. 2. In the condensate recovery pump according to claim 1, an electrically operated valve of the valve means is used to open and close the exhaust passage in response to an electrical command from a level switch provided in the steam/water separation tank. A condensate recovery pump characterized by: 3. The condensate recovery pump according to claim 1, wherein the valve means is a float type air vent valve, and the exhaust passage is mechanically opened and closed.