JPS607172B2 - Drain removal device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drain removal device for recovering and removing drains from boilers, dryers of paper machines, and other steam equipment.

In general, drain recovery is performed by steam supplied from a steam generation source, which radiates heat within the equipment, then releases the drain into the atmosphere using a steam trap, etc., and then returns the high-temperature drain water to the boiler using a pump or reduction device for recovery. However, since the steam is discarded in this open-to-atmosphere type, there is a limit to heat recovery, so there is little contribution to energy saving.
However, there were also problems with the pollution caused by the steam that spewed out.

For this reason, a nozzle is installed in the circulation path equipped with a conventional pump,
Drain removal involves sucking the drain using the negative pressure generated by the jet from the nozzle, passing the sucked drain through the air-cooled pipe in the circulation path, condensing it, and discharging it from the outlet provided in the middle of the circulation path. It has been attempted to use a device that allows the drain to be collected immediately and achieves extremely effective results, but when this device is suctioning the drain smoothly, the inlet of the centrifugal pump is at the temperature of the drain at that time. There is no problem because the pressure is raised by the jet pump to a level higher than the saturated vapor pressure at As a result, the pressure on the suction side may drop rapidly, and the inlet of the centrifugal pump may drop below the saturated vapor pressure at this temperature. At this time, cavitation occurs in the centrifugal pump, producing noise and vibration. Moreover, this tendency is true as the amount of drain on the suction side is small, the noise will be louder, and if the drain stops coming completely, the inside of the centrifugal pump will be in a mixed state of steam and drain, and the sound will no longer be generated. There is an inconvenience that the capacity of the centrifugal pump decreases and the drain removal device does not perform satisfactorily.
Moreover, the drain removal function is affected by fluctuations in the drain pressure generated by the drain generating device, resulting in unstable operation. The present invention accurately eliminates these conventional drawbacks, improves the performance of the drain removal device, eliminates the generation of noise and vibration, and significantly improves and stabilizes the drain removal ability of steam equipment.The device is simple and inexpensive. That's what we're trying to offer. Another object of the present invention is to provide a high-performance drain removal device that can reduce the load without reducing thermal efficiency, is compact, ensures proper pump operation, is highly safe, and has a large suction capacity. is also the purpose.

The present invention provides a jet nozzle section between the intake port and the discharge port of the drain, and includes a pump and a circulation path for jetting water from the jet nozzle section, and the negative pressure generated by the jet flow from the jet nozzle section. A drain or soft water system that has a mechanism for suctioning and condensing the drain using the drain pipe, and that the drain piping that fits into the drain intake port is once raised and then lowered to secure the drain amount on the suction side of the drain. Another important feature is that the drain pipe is once raised and then lowered to form a drain reservoir, and the drain pipe is then raised and then lowered to form a drain reservoir. It is characterized by being equipped with a cooling mechanism that cools the drain that is being sucked. An embodiment of the present invention will be described with reference to the drawings. The outlet of the nozzle 2 is faced into the nozzle chamber 1, and a jet receiving port 3 which also serves as a venturi is formed opposite to the outlet of the nozzle 2. The suction port 6 of the pump 5 passes through the lotus, and the discharge port 7 of the pump 5 passes through the return waterway 8 to the nozzle 2.
A circulation path is formed through the lotus. A drain inflow pipe 9 is connected to the nozzle chamber 1, and a drain outflow pipe 10 is connected to the return waterway 8 near the pump discharge port 7. A drain replenishment pipe 30 connected to the suction side pipe 9'' of the drain pipe is connected to the drain outflow pipe 101.
This bypass connection is provided as a return flow path, that is, bypass piping. A flow rate control valve 31 is provided in this pipe 30, and can be opened and closed by manual operation or automatically by a detector 32 that detects the drain flow rate or liquid level. In this case, an alarm buzzer or a warning lamp may be used in place of or in conjunction with the detector 32, or if a pumping device is used in combination, it may be controlled to start. Furthermore, in order to enhance the drain removal function, the drain inlet pipe 9 forms a drain reservoir with a riser 11, and this drain reservoir 1 is equipped with a cooling mechanism for cooling the drain, such as an inlet 12 for a cooling liquid such as cooling water or cold soot. A heat exchanger or flash tank 15 consisting of a coolant chamber 14 and an outlet 13 is interposed therebetween. In the specific example of FIG. 2, the piping 30 is used as an alternative to drain supply,
It is effective to use a water softening mechanism used in steam supply equipment such as a boiler as the soft water source 17, and as necessary, to enhance the cooling effect. Soft water injection may be used in the cooling mechanism 14, and the drain may be purged and stored in a tank for use as soft water.

In this case, a water pump may be used, but a water supply mechanism using differential pressure or suction negative pressure may also be used. In the figure, 18 is a heat radiation fin formed in the return waterway, and 19 is a strainer, which is provided at the intake part of the drain inlet pipe 9.

A separate tank 20 is interposed in the drain outflow pipe 10.

21 is a gas separator, 22 is a boiler, 23 is a flow rate control valve,
24 is a check valve, 25 is a discharge valve, 26 is a dryer, 2
7 is a steam valve, 28 is a pump motor, 29 is a cooling water source,
33 is a valve, and 34 is a water injection pipe.

When the pump 5 is operated, water is injected as a jet from the nozzle 2 into the nozzle chamber 1 through the discharge port 7 and the return waterway 8, and from the jet receiver □3 through the suction waterway 4 to the suction port 6. reach and circulate.

As a high-speed jet is ejected from the outlet of the nozzle 2, the pressure inside the nozzle chamber 1 decreases, and due to this pressure reduction, drain is sucked from the drain source such as the dryer 26 through the drain inlet pipe 9, enters the nozzle chamber 1, and flows into the jet receiving port 3.
It enters the circulation path along with the jet. When a very small amount of drain comes in from the suction side of the drain inflow pipe compared to the pump capacity, the detector 32 detects this, operates the flow rate control valve 31 to open it, and replenishes the drain or soft water. drive. In other words, in the example in Figure 1, in order to prevent noise and vibration, the drain must be over a certain amount (20% of the pump capacity).
%) Must come in smoothly. If the drain is small.
However, if you always fill the drain with an appropriate amount of soft water and ensure that a certain amount of drain comes in from the inlet, the noise and vibrations will disappear. Therefore, by returning the drain from the discharge side to the suction side so that the amount of water entering the tank does not fall below a certain level, noise and vibration will be eliminated. For this purpose, a return piping 30 from the discharge side to the suction side is used as shown in the figure, but ``This return amount only needs to be a very small amount, so 3/8B is sufficient even for an 80A pump, and 3' for a smaller pump. Even 8B is too large, so it is reasonable to add a valve in the middle to adjust the flow rate, and when adding soft water, it has the advantage of having a cooling effect and increasing suction power.On the other hand, the riser pipe that becomes the drain reservoir of the drain inlet pipe 9 Once the drain is stored in the section 11 and cooled by the cooling mechanism 14 etc., the water vapor of the drain water is condensed, becomes a jet, and is circulated through the return channel 8 together with the water that entered from the jet socket 3, so that the circulation channel is always filled. Since the drain is sucked in from the drain inflow pipe 9 and condenses in the circulation path, the amount of water increases, and this excess water is discharged from the drain outflow pipe 10, making it easy to directly collect the drain. The present invention provides a jet nozzle portion between the intake port and the discharge port of the drain, and includes a pump and a circulation path for jetting water from the jet nozzle portion, and In devices that use the negative pressure generated by the jet flow from the jet nozzle to suction drain and collect condensation, a drain or soft water is used to secure the amount of drain on the suction side of the drain piping, which is suitable for the drain intake. By installing a replenishment mechanism, drain can be quickly sucked and collected without remaining in the drain generation equipment, and the drain removal equipment can always operate in a good condition and in a high performance state without reducing the thermal efficiency of the equipment. At the same time, it can accurately prevent noise and vibration from occurring due to fluctuations in suction drain volume, ensure stable operation, increase drain suction volume, improve drain discharge capacity, and improve equipment performance.
In addition, since no cavitation phenomenon occurs in the centrifugal pump, steam traps can be omitted, making the device extremely compact, which has great advantages in terms of installation and maintenance, and drain discharge pressure can be increased, making drain transport easier. Furthermore, it can be applied to drain recovery from a very wide range of steam-using equipment, and can be used for drain discharge and reduction.Since it can be used as a frozen system, it improves heat management and saves energy by recovering heat from drains. This contributes to safe and economical operation, and also allows for stable and efficient operation of the drain removal device.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention, and FIG. 1 is a system diagram, and FIG.
The figure is a system explanatory diagram of another embodiment. 1... Nozzle chamber, 2... Nozzle, 3... Jet socket,
4...Suction waterway, 5...Pump, 6...
...Suction port, 7...Discharge port, 8...
Return waterway, 9...Drain inflow pipe, 10...Drain outlet, 11...Rising pipe section, 12...
...Inlet, 13...Outlet, 14...Cooling liquid chamber, 15...Flash tank, 16...
...Piping, 17...Soft water source, 18...
・・Radiation fin, 19・・・Strainer, 20・
... Separate tank, 21 ... Gas separator, 22 ... Boiler, 23 ... Flow rate control valve, 24 ... Check valve, 25・・・・・・
・Discharge valve, 26...Dryer, 27...Steam valve, 28...Pump motor, 29...Cooling water source, 30...Piping, 31... ...Flow control valve, 32...Detector, 33...Valve, 3
4... Water injection pipe. Figure 1 Figure 2

Claims (1)

[Scope of Claims] 1. A jet nozzle section is provided between the intake port and the discharge port of the drain, and a pump and a circulation path are provided for jetting water from the jet nozzle section, and the negative water generated by the jet flow from the jet nozzle section is provided. A system for condensation recovery by suctioning drain using pressure, characterized in that a drain or soft water replenishment mechanism is provided on the suction side of the drain piping communicating with the intake of the drain to ensure the amount of drain. Drain removal device. 2. Claim 1, wherein the replenishment mechanism comprises a return flow path connecting the suction side of the drain pipe and the drain outflow pipe.
Drain removal device as described in section. 3. The drain removal device according to claim 1, wherein the replenishment mechanism includes a communication connection pipe on the suction side of the drain pipe and is connected to a soft water supply source. 4. The drain removal device according to claim 1, 2, or 3, wherein the replenishment mechanism is connected to a drain pipe and has a flow rate control valve in the pipe. 5. The drain removal device according to claim 3 or 4, wherein the replenishment mechanism is a water softening mechanism used in steam supply equipment of equipment that generates the drain. 6 The replenishment mechanism is a pipe with a flow control valve,
The drain removal device according to claim 4 or 5, which is a flow control valve that can be opened and closed by detecting the drain flow rate or liquid level.