JP2015190742A - boiler system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a boiler system capable of reducing vibration and noise occurring according to circulation of drain.SOLUTION: A boiler system 1 includes: a boiler 11; a drain tank 20; a drain recovery line L2 for connecting load equipment 40 and the drain tank 20; a drain recovery valve 23 arranged in the drain recovery line L2; a drain supply line L3 for connecting the drain tank 20 and the boiler 11; an open tank 30 for storing make-up water; a drain escape line L8 for connecting an upstream side of the drain recovery valve 23 in the drain recovery line L2 and the open tank 30; a drain escape valve 81 arranged in the drain escape line L8; a bypass line L9 for connecting the upstream side of the drain recovery valve 23 in the drain recovery line L2 and a downstream side of the drain escape valve 81 in the drain escape line L8; and a flow rate adjustment part 91 for circulating a fluid of a predetermined flow rate in the bypass line L9.

Description

  The present invention relates to a boiler system. More specifically, the present invention relates to a closed type boiler system that collects drain discharged from a load device without supplying it to the atmosphere and supplies water to the boiler.

  Conventionally, steam generated by a boiler is supplied to the load equipment, and the drain generated by condensation of the steam used as a heat source in the load equipment is collected in a sealed drain tank with pressure resistance at high temperature and pressure. And the closed type boiler system which supplies water to a boiler again is proposed (for example, refer patent document 1).

JP2013-205006A

  In such a boiler system, when the amount of drain stored in the drain tank increases, a drain release line is provided for draining the drainage generated in the load device to the open tank side that is released to the atmosphere without being collected in the drain tank. . The flow path of the drain escape line is closed when the drain is collected in the drain tank, and is opened when the water level of the drain tank exceeds a predetermined threshold.

  However, when draining the drain from the drain escape line, the drain and the flash vapor generated from the drain are supplied to the closed and cooled flow path all at once, causing vibration and noise in the drain escape line. End up.

  Therefore, an object of this invention is to provide the boiler system which can reduce the vibration and noise which generate | occur | produce with the distribution | circulation of a drain.

  The present invention provides a boiler that generates steam and supplies it to load equipment, a drain tank that collects the drain generated by condensation of the load equipment using steam without opening it to the atmosphere, and the load equipment. A drain recovery line that connects the drain tank, a drain recovery valve that is disposed in the drain recovery line, a drain that connects the drain tank and the boiler, and supplies the drain accommodated in the drain tank to the boiler A supply line; an open tank that is open to the atmosphere and stores makeup water to be supplied to the boiler; a drain relief line that connects the upstream side of the drain recovery valve in the drain recovery line and the open tank; and the drain relief line. A drain relief valve disposed in the drain recovery line, an upstream side of the drain recovery valve in the drain recovery line, and the drain A bypass line connecting the downstream side of the drain relief valve in the down relief line relates to a boiler system and a flow rate adjusting unit for circulating a predetermined flow rate of fluid to the disposed in the bypass line the bypass line.

  Moreover, it is preferable that the said flow volume adjustment part is comprised by the flow volume adjustment valve.

  Moreover, it is preferable that the said flow volume adjustment part is comprised with an orifice.

  According to the boiler system of the present invention, it is possible to reduce vibrations and abnormal noise that occur with the circulation of drain.

It is a figure showing the composition of the boiler system concerning one embodiment of the present invention.

Hereinafter, a preferred embodiment of a boiler system of the present invention will be described with reference to the drawings.
The boiler system 1 of this embodiment is provided with the boiler apparatus 10, the drain tank 20, the open tank 30, and the control apparatus 100 as shown in FIG. Moreover, the boiler system 1 is provided with several lines which connect these apparatuses and a vapor | steam or water distribute | circulates. Specifically, the boiler system 1 includes a first steam supply line L1, a drain recovery line L2, a drain supply line L3, a second steam supply line L4, a flash steam line L5, and a makeup water line as lines. L6, a drain return line L7, a drain escape line L8, and a bypass line L9 are provided.

  As shown in FIG. 1, the boiler device 10 includes a once-through boiler 11, a steam header 12 in which steam generated in the once-through boiler 11 is collected, and a connecting pipe 13 that connects the once-through boiler 11 and the steam header 12. .

  The once-through boiler 11 generates steam by heating the feed water supplied to the inside with combustion gas. In the present embodiment, the drain collected in the drain tank 20 described later is supplied as feed water to the once-through boiler 11 (a plurality of water pipes).

As shown in FIG. 1, the steam generated in the once-through boiler 11 is supplied to the steam header 12 through a connecting pipe 13. The steam header 12 stores the steam generated by the once-through boiler 11 and supplies it to the load device 40.
The load device 40 uses the steam generated by the once-through boiler 11 as a heat source, and performs heat exchange with the object to be heated.

  The drain tank 20 is constituted by a pressure vessel having pressure resistance. The drain tank 20 collects the drain generated by condensing the steam generated by the once-through boiler 11 in the load device 40 in a high-temperature and high-pressure state. The drain tank 20 is provided with a water level sensor 25 that detects the water level of the drain collected in the drain tank 20.

  The open tank 30 is open to the atmosphere. The open tank 30 stores makeup water supplied to the once-through boiler 11. In addition, flush steam generated from the drain in the drain tank 20 and drain that flows through a drain escape line L8 described later are introduced into the open tank 30.

The first steam supply line L <b> 1 connects the steam header 12 and the load device 40, and supplies the steam generated by the once-through boiler 11 to the load device 40.
The drain recovery line L <b> 2 connects the load device 40 and the drain tank 20, and supplies the drain generated in the load device 40 to the drain tank 20. A steam trap 21, a check valve 22, a drain recovery valve 23, and a pressure sensor 24 are arranged in the drain recovery line L2. The steam trap 21 is disposed on the downstream side of the load device 40 in the drain recovery line L2, discharges the drain generated in the load device 40, and prevents the discharge of steam. The check valve 22 is disposed on the downstream side of the steam trap 21 and prevents the drain from flowing back to the load device 40 side in the drain recovery line L2. The drain recovery valve 23 is disposed in the vicinity of the connection portion with the drain tank 20 in the drain recovery line L2. The drain recovery valve 23 is configured by an air drive valve. The drain recovery valve 23 operates based on a control signal from the control device 100, and opens and closes the flow path of the drain recovery line L2. The pressure sensor 24 is disposed between the check valve 22 and the drain recovery valve 23 in the drain recovery line L2, and measures the pressure of the drain inside the drain recovery line L2.

The drain supply line L <b> 3 connects the drain tank 20 and the once-through boiler 11, and supplies the drain collected in the drain tank 20 to the once-through boiler 11. A drain pump 31 and a drain supply valve 32 are arranged in the drain supply line L3.
The drain pump 31 boosts the drain supplied from the drain tank 20 and sends it out to the once-through boiler 11 side. The drain supply valve 32 is configured by a motor valve. The opening of the drain supply valve 32 is adjusted by the control device 100, and thereby the amount of drain supplied to the once-through boiler 11 is controlled.

  The second steam supply line L4 connects the steam header 12 and the drain tank 20. The second steam supply line L4 supplies the steam generated in the once-through boiler 11 to the drain tank 20 and adjusts the pressure inside the drain tank 20. A pressure regulating valve 41 and an air drive valve 42 are disposed in the second steam supply line L4.

  The flash steam line L5 connects the drain tank 20 and the open tank 30, and discharges the flash steam generated in the drain tank 20 to the open tank 30. A pressure regulating valve 51 is disposed in the flash steam line L5. When the pressure inside the drain tank 20 exceeds a predetermined pressure, the pressure regulating valve 51 releases the flash steam to the open tank 30 side and reduces the pressure inside the drain tank 20.

  The makeup water line L <b> 6 connects the open tank 30 and the drain tank 20, and supplies water stored in the open tank 30 to the drain tank 20. A makeup water pump 61 is disposed in the makeup water line L6.

  The drain return line L7 connects the drain supply line L3 and the drain tank 20. More specifically, the upstream (base end) end of the drain return line L7 is connected between the drain pump 31 and the drain supply valve 32 in the drain supply line L3. The downstream end of the drain return line L7 is branched into a line connected to the upper part of the drain tank 20 and a line connected to the lower part of the drain tank 20. A motor valve 71 is disposed on a line connected to the upper portion of the drain tank 20, and an orifice 72 is disposed on a line connected to the lower portion of the drain tank 20.

  The drain return line L7 returns a part or all of the drain flowing through the drain supply line L3 to the drain tank 20. More specifically, from the line connected to the lower part of the drain tank 20, the drain is circulated to the liquid phase part of the drain tank 20, and from the line connected to the upper part of the drain tank 20, the gas phase of the drain tank 20 is Drain is circulated in the part. In this drain return line L7, the flow rate of the drain circulated to the liquid phase part is adjusted by the orifice 72 to make the temperature of the drain stored in the drain tank 20 uniform, and by the drain circulated to the gas phase part, The flash steam generated inside the drain tank 20 is recovered.

  The drain escape line L8 connects the drain recovery line L2 and the open tank 30. The drain escape line L8 allows the drain flowing through the drain recovery line L2 to escape to the open tank 30 when the drain recovered in the drain tank 20 becomes excessive. A drain relief valve 81 is disposed in the drain relief line L8. The drain relief valve 81 is constituted by an air driven valve. The drain relief valve 81 operates based on a control signal from the control device 100, and opens and closes the flow path of the drain relief line L8.

  The bypass line L9 connects the upstream side of the drain recovery valve 23 in the drain recovery line L2 and the downstream side of the drain relief valve 81 in the drain relief line L8. The bypass line L9 bypasses part of the drain flowing through the drain recovery line L2 to the drain escape line L8. In the present embodiment, the upstream end portion of the bypass line L9 is connected to the upstream side of the connection portion with the drain escape line L8 in the drain recovery line L2. An adjustment valve 91 as a flow rate adjustment unit is disposed in the bypass line L9.

  The adjustment valve 91 is configured by a manual valve or an automatic valve whose opening degree can be adjusted based on a control signal from the control device 100, and distributes a fluid (drain and / or flush steam) having a predetermined flow rate. In the present embodiment, the opening degree of the adjustment valve 91 is set so that a drain having a flow rate (amount of heat) that can maintain a state in which the drain relief line L8 is warmed to a predetermined temperature constantly flows. From the viewpoint of effectively reducing vibration and noise in the drain escape line L8, it is preferable that the amount of drain that always flows through the adjustment valve 91 (bypass line L9) is equivalent to the heat release amount of the drain escape line L8. For example, when the drain escape line L8 has a nominal diameter of 80A and a length of 10 m and is kept warm, the heat dissipation amount is 400 kcal / h to 800 kcal / h.

  The control device 100 includes a CPU as a control unit and a memory as a storage unit, and controls the boiler system 1 by controlling opening and closing of various valves and operations of various pumps. In the present embodiment, the control device 100 controls the opening and closing of the drain recovery valve 23 and the drain relief valve 81 based on the water level of the drain tank 20 detected by the water level sensor 25. Specifically, when the water level detected by the water level sensor 25 is equal to or lower than a predetermined threshold, the control device 100 opens the drain recovery valve 23 and closes the drain relief valve 81, and circulates through the drain recovery line L2. The drain to be collected is collected in the drain tank 20.

  On the other hand, when the water level detected by the water level sensor 25 exceeds a predetermined threshold value, the control device 100 first opens the drain relief valve 81, and after a predetermined time (for example, 10 seconds) has elapsed, the control unit 100 opens the drain recovery valve 23. Close. Thereby, the drain which distribute | circulates the drain collection line L2 is escaped to the open tank 30 through the drain escape line L8.

  Here, in the present embodiment, the boiler system 1 includes a bypass line L9 that connects the upstream side of the drain recovery valve 23 in the drain recovery line L2 and the downstream side of the drain relief valve 81 in the drain relief line L8, and this bypass line. And an adjustment valve 91 disposed at L9. And the adjustment valve 91 is set to the opening degree through which the drain of the heat quantity that can maintain the state where the drain escape line L8 is heated to a predetermined temperature flows. Thereby, since a small amount of drain can be continuously circulated to the drain escape line L8 from the bypass line L9 in which the adjustment valve 91 is arranged, the drain escape line L8 can be kept warm. Therefore, when the drain relief valve 81 is opened and the drain is allowed to escape to the open tank 30 side, it is possible to reduce the occurrence of vibration and noise due to the drain and / or flash steam flowing through the drain relief line L8.

  Moreover, the opening degree of the adjustment valve 91 is set so that a small amount of drain with a flow rate (amount of heat) that can maintain the state where the drain escape line L8 is warmed to a predetermined temperature is always circulated, thereby improving the thermal efficiency of the boiler system 1. Generation of vibration and noise can be reduced while suppressing the decrease.

As mentioned above, although one preferable embodiment of the boiler system 1 of this invention was described, this invention is not restrict | limited to embodiment mentioned above and can change suitably.
For example, in the present embodiment, the boiler system 1 is configured by a single once-through boiler 11, but is not limited thereto. That is, the boiler system may be configured to include a plurality of once-through boilers.

  In this embodiment, an air drive valve or a motor valve is used as a valve. However, the present invention is not limited to this, and the type of valve may be changed as appropriate.

  Moreover, in this embodiment, although the flow volume adjustment part was comprised by the adjustment valve 91, it is not restricted to this. That is, the flow rate adjusting unit may be configured by an orifice.

1 Boiler system 11 Once-through boiler (boiler)
20 Drain tank 30 Open tank 40 Load device 23 Drain recovery valve 81 Drain relief valve 91 Adjustment valve (flow rate adjustment part)
L2 Drain recovery line L3 Drain supply line L8 Drain relief line L9 Bypass line

Claims (3)

A boiler that generates steam and supplies it to load equipment;
A drain tank that collects the drain generated by condensation of the load device using steam without opening it to the atmosphere;
A drain recovery line connecting the load device and the drain tank;
A drain recovery valve disposed in the drain recovery line;
A drain supply line for connecting the drain tank and the boiler and supplying the boiler with the drain stored in the drain tank;
An open tank that is open to the atmosphere and stores makeup water to be supplied to the boiler;
A drain relief line connecting the upstream side of the drain recovery valve in the drain recovery line and the open tank;
A drain relief valve disposed in the drain relief line;
A bypass line connecting the upstream side of the drain recovery valve in the drain recovery line and the downstream side of the drain relief valve in the drain relief line;
A boiler system comprising: a flow rate adjusting unit that is disposed in the bypass line and causes a predetermined flow rate of fluid to flow through the bypass line.   The boiler system according to claim 1, wherein the flow rate adjustment unit includes a flow rate adjustment valve.   The boiler system according to claim 1, wherein the flow rate adjusting unit includes an orifice.

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