JP4722664B2 - Steam desuperheater - Google Patents

Description

  The present invention relates to a steam temperature reducing apparatus capable of reducing the temperature of steam in a high temperature state to a predetermined temperature, for example, a saturated steam temperature.

  The steam temperature reducing device supplies a cooling fluid such as cooling water to overheated high temperature steam to reduce the temperature of the steam to a predetermined temperature.

In this steam temperature reducing device, the secondary side drain (condensate) of the heating container, that is, the liquid, is used as a cooling fluid to contact the high temperature steam to reduce the temperature of the steam. There has been a problem that temperature unevenness occurs in the reduced temperature steam without being reduced in temperature. That is, even if the cooling water is supplied to the high-temperature steam through a nozzle or the like, the steam and water droplets are not mixed uniformly and entirely, resulting in temperature unevenness.
Japanese Patent Publication No. 7-88933

  The problem to be solved is to provide a steam temperature reducing device in which the high temperature steam and the cooling fluid are uniformly and uniformly mixed so as not to cause temperature unevenness in the temperature reduced steam.

In the present invention, a cooling fluid is supplied into high-temperature steam to reduce the temperature of the high-temperature steam to a predetermined temperature state.A steam ejector is attached to the high-temperature steam supply pipe, and the steam ejector has a double-pipe structure. the inside of the double pipe structure with an ejector passage flowing down of steam, as a heat exchange unit comprising a low-temperature steam outside the cooling fluid is the heat exchange of the double pipe structure, the upper end portion of the heat exchange portion of the outer A pipe line is attached to the suction port of the steam ejector, and a cooling fluid tank is connected to the lower part of the outer heat exchanging part via a communication pipe, and a steam trap is connected to the front side of the cooling fluid tank of the communication pipe. A cooling path is attached to the lower side surface of the cooling fluid tank, a circulation pump is connected, and the upper end of the circulation path is used as a cooling fluid supply pipe to supply the cooling fluid supply pipe to the outer heat exchange unit. Attaching a control valve for controlling the amount of body, in which a low-temperature steam generated in the heat exchange unit is supplied from the suction port of the steam ejector into high-temperature steam in.

  In the steam temperature reducing device of the present invention, the high-temperature steam and the cooling fluid are heat-exchanged in the heat exchange section outside the double-pipe structure, the cooling fluid is evaporated to become low-temperature steam, and mixed with the high-temperature steam in the steam ejector. By this, it becomes quick mixing of the steam of high temperature steam and low temperature steam, and high temperature steam can be reduced in temperature without unevenness.

  The present invention heat-exchanges the high-temperature steam and the cooling fluid in the heat exchange section outside the double-pipe structure, and evaporates the cooling fluid to generate low-temperature steam. The heat exchange with the cooling fluid is preferably such that the high-temperature steam and the cooling fluid indirectly exchange heat.

  FIG. 1 is a block diagram of an embodiment of the present invention, in which a steam temperature reducing device includes a high-temperature steam supply pipe 1 through which a superheated high-temperature steam flows down from the left side to the right side, and a steam ejector 2 having a double-pipe structure. Configure.

  The steam ejector 2 having a double-pipe structure has an inner passage 4 as an ejector passage connected to the high-temperature steam supply pipe 1 and an outer sealed space 5 as a heat exchange section. A cooling fluid supply pipe 6 to be described later is connected to the upper part of the outer heat exchange section 5. Although not shown, a spray nozzle for spraying the cooling fluid into the heat exchange unit 5 is attached to the end of the cooling fluid supply pipe 6 in the heat exchange unit 5. Connected to the outlet side of the inner ejector passage 4 is a temperature-reducing steam pipe 7 that causes the steam, which has been reduced in temperature to a predetermined temperature, to flow down to the location where the temperature-reducing steam is used.

  The pipe line 3 is attached to the upper end portion of the outer heat exchanging portion 5 and connected to the suction port 14 of the steam ejector 2. A check valve 17 is attached to the pipeline 3. The check valve 17 allows only the flow of fluid from the outer heat exchange section 5 to the suction port 14 and prevents passage of fluid in the opposite direction.

A communication pipe 11 communicating with the inside of the heat exchange unit 5 is connected to a lower part of the heat exchange unit 5 and connected to a cooling fluid tank 12 disposed below. A steam trap 13 is attached to the front side of the tank 12 of the communication pipe 11. The steam trap 13 passes and discharges only the cooling fluid as a liquid to the tank 12 side in the mixed fluid of the cooling fluid flowing down in the communication pipe 11 and the low-temperature steam evaporated from the cooling fluid, Low temperature steam is not allowed to pass through.

  A cooling fluid supply pipe 18 for supplying a cooling fluid such as cooling water is connected to the cooling fluid tank 12 at an upper portion, and a predetermined amount of the cooling fluid 20 is stored inside the tank 12. The cooling fluid supply pipe 18 is provided with an open / close valve 19 that can open and close the pipe line.

  A circulation path 22 is attached to the lower side surface of the cooling fluid tank 12 and a circulation pump 21 is connected thereto. Let the upper end of the circulation path 22 be the cooling fluid supply pipe 6. Further, the surplus fluid discharge pipe 23 is connected to the lower left side surface of the cooling fluid tank 12. An opening / closing valve 24 is attached to the surplus fluid discharge pipe 23, while a control valve 25 is attached to the cooling fluid supply pipe 6 for controlling the amount of cooling fluid supplied to the outer heat exchange unit 5.

  The high-temperature steam that flows down from the left side to the right side of the high-temperature steam supply pipe 1 flows through the ejector passage 4 inside the steam ejector 2, thereby generating a suction force. The fluid in the heat exchange unit 5 is sucked. Due to this suction force, the inside of the heat exchanging unit 5 is in a vacuum pressure state lower than the atmospheric pressure. Therefore, the cooling fluid 20 in the tank 12 supplied from the cooling fluid supply pipe 6 into the heat exchanging section 5 takes away the heat of a part of the high temperature steam flowing down the inner ejector passage 4 and immediately evaporates to form the low temperature steam. It becomes. As described above, the high temperature steam and the cooling fluid exchange heat with the steam ejector 2, so that the temperature of the high temperature steam is lowered by a certain temperature.

The low temperature steam generated in the heat exchanging section 5 is sucked into the suction port 14 of the steam ejector 2 through the check valve 17, mixed with the high temperature steam flowing down from the high temperature steam supply pipe 1, and reduced in temperature to a predetermined temperature. The temperature-reducing steam pipe 7 flows down. In this way, by mixing the high temperature steam and the low temperature steam with the steam ejector 2, the low temperature steam is spread over the entire high temperature steam, and temperature unevenness of the reduced temperature steam can be prevented.

The amount of the cooling fluid supplied to the outer heat exchange unit 5 can be arbitrarily controlled by appropriately adjusting the valve opening of the control valve 25. Further, the temperature of the cooling fluid supplied to the heat exchanging unit 5 can be arbitrarily controlled by adjusting the amount of the cooling fluid supplied to the cooling fluid tank 12.

The block diagram which shows the Example of the steam temperature decreasing apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High temperature steam supply pipe 2 Steam ejector 4 Inner ejector passage 5 Outer heat exchange part 6 Cooling fluid supply pipe 7 Temperature-reducing steam pipe 12 Cooling fluid tank 13 Steam trap 14 Suction port 17 Check valve 18 Cooling fluid supply pipe 21 Circulation Pump 22 Circulation path 25 Control valve

Claims (1)

A cooling fluid is supplied into the high temperature steam to reduce the temperature of the high temperature steam to a predetermined temperature state. A steam ejector is attached to the high temperature steam supply pipe, the steam ejector has a double pipe structure, and the double pipe The inside of the structure is an ejector passage through which steam flows down, and the outside of the double-pipe structure is used as a heat exchanging part in which the cooling fluid exchanges heat to become low-temperature steam, and a pipe line is connected to the upper end of the outer heat exchanging part. Attached and connected to the suction port of the steam ejector, connected to the cooling fluid tank through the communication pipe at the lower part of the outer heat exchange section, attached a steam trap on the front side of the cooling fluid tank of the communication pipe, A circulation path is attached to the lower side surface of the cooling fluid tank, a circulation pump is connected, and the upper end of the circulation path is used as a cooling fluid supply pipe. Attach the control valve to Control, steam decreased temperature apparatus a low temperature steam generated in the heat exchanger unit and supplying from the suction port of the steam ejector into high-temperature steam in.

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