JP2010216697A - Air heating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an air heating device capable of securely discharging generated steam condensate to the outside of a container via a steam trap. <P>SOLUTION: A steam supply pipe 3 is connected to an inlet header 19 of a heat exchanger 1 via a control valve 7. An outlet header 20 of the heat exchanger 1 and a liquid pressure-feeding member 5 are connected to each other via check valves 11, 12. The outlet header 20 and the liquid pressure-feeding member 5 communicate with each other via a communication pipe 14. The liquid pressure-feeding member 5 is connected with a high-pressure steam supply pipe 15. A pressure-feeding port 17 of the liquid pressure-feeding member 5 is connected to a liquid ejector 6. A suction chamber 10 of the liquid ejector 6 is connected to an outlet side of the steam trap 4. The outlet side of the steam trap 4 is brought into a predetermined low-pressure state by a suction force generated by the liquid ejector 6, and the steam condensate can be securely discharged to the outside. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

 The present invention relates to an air heating apparatus for heating air with heating steam supplied via a control valve.

As a conventional air heating device, for example, a fin tube type air heating device is a steam generated in a heat exchanger by immediately injecting outside air into the outlet header when the inside of the outlet header of the heat exchanger becomes a vacuum. The condensate as the condensed water can be quickly discharged out of the vessel via the steam trap, and the condensate can be prevented from staying in the heat exchanger.

In the above conventional air heating device, even when outside air is injected into the outlet header, the pressure cannot be raised to atmospheric pressure or higher, and the pressure on the outlet side of the steam trap is atmospheric pressure. There was a problem that the pressure difference between the inlet side and the outlet side of the trap could hardly be secured, and the condensate could not be discharged reliably from the steam trap. The steam trap cannot quickly discharge condensate to the outlet side unless a predetermined pressure difference acts on the inlet side and the outlet side.

Japanese Patent Publication No.51-31998

  The problem to be solved is to ensure that a predetermined pressure difference is secured between the inlet side and the outlet side of the steam trap, and to reliably discharge the condensate generated in the heat exchanger to the outside through the steam trap. It is.

 In the present invention, the air passing through the heat exchanger is heated with the heating steam supplied via the control valve, and the condensed water is extracted from the steam trap. The liquid pumping member is connected to the heat exchanger via a check valve, the liquid ejector is connected to the pumping port of the liquid pumping member, and the suction chamber of the liquid ejector is connected to the outlet side of the steam trap. is there.

  According to the present invention, a liquid ejector is communicated with the pumping port of the liquid pumping member, and the suction chamber of the liquid ejector is connected to the outlet side of the steam trap, thereby the outlet of the steam trap. The side can be in a reduced pressure state below atmospheric pressure, ensuring a sufficient pressure difference between the inlet side and the outlet side of the steam trap, so that the condensate generated in the heat exchanger can be reliably discharged to the outside. There is an advantage.

It is a block diagram which shows the Example of the air heating apparatus which concerns on this invention.

In the present invention, a liquid pumping member is connected to a heat exchanger via a check valve. The liquid pumping member is a conventionally known pump that pumps a liquid accumulated inside using high-pressure steam or compressed air as a driving fluid. Can be used.

  In FIG. 1, a fin-tube heat exchanger 1, a steam supply pipe 3 connected to an inlet header 19 of the heat exchanger 1, a steam trap 4 communicating below an outlet header 20 of the heat exchanger 1, and an outlet The liquid heating member 5 arranged on the right side of the header 20 and the liquid ejector 6 communicating below the liquid pumping member 5 constitute an air heating device.

A control valve 7 for controlling the amount of steam supplied to the heat exchanger 1 is attached to the steam supply pipe 3. The air passing through the heat exchanger 1 is heated by the heating steam supplied from the steam supply pipe 3 to the heat exchanger 1.

The lower end of the outlet header 20 of the heat exchanger 1 is connected to the inlet side of the steam trap 4 through a pipe line 8. The outlet side of the steam trap 4 is connected to the suction chamber 10 of the liquid ejector 6 by a conduit 9.

A vertically cylindrical liquid pumping member 5 is disposed on the right side of the outlet header 20. The liquid pumping member 5 is connected to the outlet header 20 via the check valves 11 and 12. The check valves 11 and 12 allow the flow of fluid from the outlet header 20 to the liquid pumping member 5 side, but prevent the flow of fluid in the opposite direction.

A communication pipe 14 is connected to the upper part of the liquid pumping member 5 via the on-off valve 13 to communicate the outlet header 20 and the upper part of the liquid pumping member 5. Further, a high-pressure steam supply pipe 15 is connected to the upper part of the liquid pumping member 5, and an on-off valve 16 is attached to the high-pressure steam supply pipe 15. In addition, a liquid level detection mechanism for detecting the liquid level is incorporated in the liquid pumping member 5 (not shown).

The pumping port 17 at the lower end of the liquid pumping member 5 is connected to a nozzle portion (not shown) in the suction chamber 10 of the liquid ejector 6 through a pipe line 18. The condensate as the liquid accumulated in the liquid pumping member 5 is pumped from the pumping port 17 to the liquid ejector 6 by the high-pressure steam from the high-pressure steam supply pipe 15 and generates a suction force in the suction chamber 10 of the liquid ejector 6. is there.

 When the liquid level detection mechanism in the liquid pumping member 5 detects a low liquid level, the on-off valve 16 of the high-pressure steam supply pipe 15 is closed, while the on-off valve 13 of the communication pipe 14 is opened, so that the liquid The inside of the pressure feeding member 5 and the inside of the outlet header 20 are in the same pressure state, and the condensate accumulated in the outlet header 20 flows into the liquid pressure feeding member 5 through the check valves 11 and 12.

  When the liquid level detection mechanism in the liquid pumping member 5 detects a high liquid level, the on-off valve 13 of the communication pipe 14 is closed, while the on-off valve 16 of the high-pressure steam supply pipe 15 is opened, and the high-pressure steam supply pipe High-pressure steam flows from 15 into the liquid pumping member 5, and condensate accumulated therein is pumped from the pumping port 17 to the liquid ejector 6.

  When the air passing through the heat exchanger 1 is heated, by supplying a predetermined amount of steam from the steam supply pipe 3 and the control valve 7 to the inlet header 19, the air passing through the outer periphery of the fin tube is heated by the steam. The Normally, the amount of steam supplied is sufficient, and the heat exchanger 1 maintains a high pressure state. Condensate condensed by heating passes through the steam trap 4 from the pipe line 8 at the lower end of the outlet header 20, and is further discharged outside through the inside of the liquid ejector 6. In this case, since the inside of the outlet header 20 is in a high pressure state, the generated condensate is discharged to the outside due to the pressure difference, and the liquid ejector 6 is not driven.

  When the amount of steam supplied from the control valve 7 to the inlet header 19 decreases and the pressure in the heat exchanger 1 also decreases, the amount of condensate discharged from the steam trap 4 also decreases. When the pressure in the heat exchanger 1 and the outlet header 20 is reduced to a pressure of about atmospheric pressure or lower than the atmospheric pressure, no condensate is discharged from the steam trap 4, so that condensate stays in the lower part of the outlet header 20. And the inside of the liquid pumping member 5 also becomes the same liquid level as the outlet header 20.

  When the liquid level detection mechanism in the liquid pumping member 5 detects this high liquid level, the on-off valve 13 of the communication pipe 14 is closed, while the on-off valve 16 of the high-pressure steam supply pipe 15 is opened to supply high-pressure steam. High-pressure steam flows from the pipe 15 into the liquid pumping member 5, and condensate accumulated inside is pumped from the pumping port 17 to the liquid ejector 6.

When condensate is supplied to the liquid ejector 6, a suction force is generated in the suction chamber 10, and the outlet side of the steam trap 4 is maintained at a pressure lower than atmospheric pressure and lower than that in the outlet header 20. The condensed water in the outlet header 20 passes through the steam trap 4 and is sucked into the liquid ejector 6 and discharged to the outside.

  It can be applied as a condensate discharge device from various air heaters using steam as a heat source.

DESCRIPTION OF SYMBOLS 1 Heat exchanger 3 Steam supply pipe 4 Steam trap 5 Liquid pumping member 6 Liquid ejector 7 Control valve 10 Suction chamber 11, 12 Check valve 13 On-off valve 15 High-pressure steam supply pipe 16 On-off valve 17 Pressure feed port

Claims (1)

  The heat exchanger that heats the air that passes through the heat exchanger with the heating steam supplied through the control valve and discharges the condensed condensate from which the steam has been deprived of heat from the steam trap. An air characterized in that a liquid pumping member is connected via a check valve, a liquid ejector is connected to a pumping port of the liquid pumping member, and a suction chamber of the liquid ejector is connected to an outlet side of the steam trap. Heating device.