JP2007332859A - Steam ejector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive steam ejector which needs no electricity, high-pressure air source or the like, and is easy to set. <P>SOLUTION: A suction chamber 2 of the ejector is connected to a steam pip 8 through a pressure reducing valve 1. A gas-liquid separator 6 and a steam trap 7 are integrally mounted on a lower part of the pressure reducing valve 1. An outlet pipe 11 is connected to a diffuser 4 of the ejector. One end of a conduit 5 is connected to the middle of the outlet pipe 11, and the other end thereof is connected to a secondary side pressure detection port 3 of the pressure reducing valve 1. The suction chamber 2 of the ejector is connected with a revaporization tank 13. Since the steam pressure detected in the conduit 5 is kept at a predetermined constant pressure by the pressure reducing valve 1 as a self-operated pressure regulating valve without needing a driving force such as electricity or high-pressure air, the steam ejector can be reduced in cost and simplified in structure. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a steam ejector that ejects drive steam from a nozzle at high speed and generates suction force in a suction chamber by velocity energy of the fluid.

  The steam ejector is connected to a pressure control valve on the inlet side of a suction chamber with a built-in nozzle, and a pressure sensor is attached to the outlet side of the diffuser, and the valve opening of the pressure control valve is driven according to the detected value of this pressure sensor. By controlling, the suction force generated in the suction chamber can be controlled.

This steam ejector requires an electric circuit that electrically connects the pressure sensor and the pressure control valve, and electricity and a high-pressure air source for driving the pressure control valve as the other force type pressure control valve. In addition, the ejector device itself becomes expensive, and there is a problem that a lot of cost is required for installing the device.
JP 2003-269400 A

  The problem to be solved is to provide a steam ejector that does not require electricity, a high-pressure air source, or the like, is easy to install, and is inexpensive.

  The present invention comprises a nozzle part composed of pores for restricting fluid, a suction chamber formed around the nozzle part, and a diffuser communicating with the suction chamber and the nozzle part. A pressure reducing valve is connected, and the secondary pressure detection port of the pressure reducing valve is connected to the outlet side portion in the diffuser or the outlet side portion of the diffuser.

  In the steam ejector of the present invention, the pressure reducing valve is connected to the inlet side of the nozzle portion, and the secondary pressure detection port of the pressure reducing valve is connected to the outlet side portion in the diffuser or the outlet side portion of the diffuser. Therefore, the pressure reducing valve is a self-acting pressure regulating valve, which does not require electricity or high-pressure air as a driving source, does not require a pressure sensor, and can be an inexpensive and simple steam ejector.

  The present invention uses a pressure reducing valve as a self-acting pressure regulating valve. As this pressure reducing valve, a pressure reducing member such as a diaphragm, a bellows, or a piston is provided on a surface of a secondary side pressure detecting port. When the secondary pressure is applied and a predetermined elastic force such as a coil spring is applied to the other surface of the pressure-sensitive member and the secondary pressure of the pressure reducing valve is lower than the predetermined elastic force of the coil spring, the main valve of the pressure reducing valve opens. Then, it is preferable that the pressure on the secondary side of the pressure reducing valve can be maintained at a predetermined value by causing the high pressure steam on the primary side of the pressure reducing valve to flow down to the secondary side.

  In FIG. 1, a pressure reducing valve 1, a suction chamber 2 containing a nozzle portion, a diffuser 4, and a pipe line 5 that connects an outlet side portion of the diffuser 4 and a secondary side pressure detection port 3 of the pressure reducing valve 1. The steam ejector is composed of

  The pressure reducing valve 1 is a pressure reducing valve as a self-acting pressure adjusting valve. The pressure on the outlet side of the diffuser 4 is applied to the secondary pressure detecting port 3 from the duct 5, and one surface of a pressure sensitive member such as a diaphragm (not shown). By applying this pressure, the outlet side pressure of the diffuser 4 can be maintained at a predetermined value.

  A steam pipe 8 communicating with a high-pressure steam source is connected to the inlet side of the pressure reducing valve 1, and a gas-liquid separator 6 and a steam trap 7 are integrally provided below the pressure reducing valve 1. In the gas-liquid separator 6, the condensate as a liquid mixed in the steam flowing into the pressure reducing valve 1 from the steam pipe 8 is separated from the steam, and further condensate separated by the steam trap 7. Can be discharged outside the system. A communication pipe 10 with a check valve 9 interposed is connected to the lower part of the steam trap 7.

  The suction chamber 2 incorporating the nozzle part and the diffuser 4 constitute an ejector. In the present embodiment, an example is shown in which one end of the pipe line 5 is connected to the outlet side part away from the diffuser 4, but one end of the pipe line 5 is connected to the outlet side in the diffuser 4 without leaving the diffuser 4. You can also. One end of the pipe 5 is preferably connected to a position where the process steam pressure supplied from the outlet pipe 11 to a steam using device (not shown) or the like can be detected. A suction passage 12 into which a fluid sucked in the suction chamber 2 flows is provided at the lower end of the suction chamber 2.

  A reevaporation tank 13 is connected to the lower part of the suction passage 12. The re-evaporation tank 13 has a vertically long cylindrical shape, and a high-temperature condensate inflow pipe 14 is connected to the central portion on the left side and a condensate discharge pipe 15 is connected to the lower side of the right side. A steam trap 16 is interposed in the condensate discharge pipe 15. Further, the lower end of the communication pipe 10 attached to the lower part of the steam trap 7 of the pressure reducing valve 1 is connected to the upper part of the reevaporation tank 13.

  Inside the re-evaporation tank 13, the high-temperature condensate flowing from the high-temperature condensate inflow pipe 14 is re-evaporated and becomes steam again, and is sucked from the suction passage 12 into the suction chamber 2 of the ejector. Condensate whose temperature has decreased to some extent after re-evaporation passes through the steam trap 16 and is discharged from the condensate discharge pipe 15 to the outside of the system.

  The high-pressure steam supplied from the steam pipe 8 is decompressed to a predetermined pressure by the pressure reducing valve 1 and supplied to the nozzle part built in the suction chamber 2 of the ejector, and the driving steam is throttled at this nozzle part to become a high-speed flow. As a result, a suction force is generated to suck the re-evaporated vapor from the suction passage 12. The sucked re-evaporated steam is mixed with the driving steam and supplied to the steam using device or the like from the outlet pipe 11 through the diffuser 4.

  The vapor pressure passing through the outlet pipe 11 is transmitted to the secondary side pressure detection port 3 of the pressure reducing valve 1 through the pipe line 5, thereby being equal to the set pressure set by the coil spring or the like of the pressure reducing valve 1. Maintained.

  By providing the gas-liquid separator 6 and the steam trap 7 at the lower part of the pressure reducing valve 1, the steam supplied to the nozzle part built in the suction chamber 2 of the ejector has a high dryness in which condensate is not mixed. It is steam, and the suction force in the suction chamber 2 of the ejector can be maintained at the highest level.

  The high-temperature condensate separated by the gas-liquid separator 6 below the pressure reducing valve 1 flows down from the steam trap 7 to the re-evaporation tank 13 and is re-evaporated, and is sucked into the suction chamber 2 of the ejector. It is possible to effectively recover the heat energy that is generated.

  In the present embodiment, the example in which the pressure reducing valve 1 and the suction chamber 2 of the ejector are connected via a pipe line is shown, but the outlet side of the pressure reducing valve 1 is directly connected to the ejector suction chamber without passing through the pipe line. 2 can also be connected.

The block diagram which shows the Example of the steam ejector of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pressure reducing valve 2 Suction chamber 3 Secondary pressure detection port 4 Diffuser 5 Pipe 6 Gas-liquid separator 7 Steam trap 8 Steam pipe 11 Outlet pipe 12 Suction passage 13 Re-evaporation tank 14 High temperature condensate inflow pipe 15 Condensate discharge pipe 16 Steam trap

Claims (1)

A pressure reducing valve is connected to the inlet side of the nozzle part in a nozzle part composed of a fine hole for restricting fluid, a suction chamber formed around the nozzle part, and a diffuser communicating with the suction chamber and the nozzle part. And the steam ejector characterized by connecting the secondary side pressure detection port of the said pressure reduction valve with the exit side part in a diffuser, or the exit side part of a diffuser.

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