JPS6119283Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a deaerator for degassing and removing air, carbon dioxide, etc. dissolved in water from water.

The feed water used for boilers, steam equipment, etc. is not only natural water but also distilled water obtained by condensing water vapor, and this feed water contains air, carbon dioxide, etc., and if left as it is, the gas will be separated during heating. In particular, since oxygen dissolved in the water supply causes corrosion of heating pipes and other related equipment, it is necessary to remove these gases by degassing in advance.

Conventionally, in this type of deaerator, the inside of a closed casing is divided by a partition wall into an upper primary deaeration chamber and a lower secondary deaeration chamber, and the primary deaeration chamber has an upper part. A spray nozzle for water supply is provided at the bottom, and an annular tray is provided at the bottom, while a gas-liquid contact device communicating with both the secondary deaeration chamber and the primary deaeration chamber is provided in the secondary deaeration chamber, and a heated steam introduction pipe is provided in the secondary deaeration chamber. A deaerator consisting of an opening is commonly used.

This type of deaerator performs primary deaeration by bringing the water supplied into the primary deaeration chamber into contact with the steam rising from the secondary deaeration chamber to the primary deaeration chamber. The degassed feed water is brought into contact with the heating steam initially supplied to the secondary deaeration chamber in a gas-liquid contact device in the secondary deaeration chamber to perform secondary deaeration.

Therefore, a large amount of steam passes through the gas-liquid contacting device in the secondary degassing chamber, so perforated shelves or serrated-edged troughs are stacked through which water is poured to form a thin film that connects to the heated steam. In a so- ^called tray-type gas-liquid contact device, which performs deaeration by increasing the contact area of is 5450
Kg/Hr, if the area through which the steam passes through the tray is narrow, a "flattening phenomenon" occurs in which the supply water cannot descend due to the rising steam, which impedes smooth deaeration. In order to avoid this, the area through which the steam passes in the tray must be made unnecessarily large, and as a result, the size of the deaerator is unavoidable.

The present invention aims to achieve deaeration that can efficiently deaerate the water supply while suppressing the occurrence of the above-mentioned flattening phenomenon. The primary deaeration chamber is divided into an upper primary deaeration chamber and a lower secondary deaeration chamber, and the primary deaeration chamber is provided with a water supply spray nozzle in the upper part and an annular tray in the lower part. In a deaerator, a gas-liquid contact device communicating with both the secondary deaeration chamber and the primary deaeration chamber is provided in the deaeration chamber, and a heated steam introduction pipe is opened. A riser pipe for communicating the secondary deaeration chamber with the primary deaeration chamber is provided in the cylindrical side wall extending downwardly toward the secondary deaeration chamber, and a riser pipe for communicating the secondary deaeration chamber with the primary deaeration chamber is provided in the upper surface of the partition wall. The primary degassing chamber is provided so as to protrude upward from the primary deaeration chamber.

An embodiment of the present invention will be described below with reference to the accompanying drawings.

Mounting legs 25 on the top surface of the deaerated water storage tank 22
Inside the closed casing 1 placed through the
The upper part is divided into a primary deaeration chamber 4 and the lower part is divided into a secondary deaeration chamber 5, with a substantially horizontal partition wall 3 having an opening 2 in the center as a passage for water droplets and steam. At the upper part of the header 4, a header 8 is provided, in which a plurality of spray nozzles 6 are arranged and a water supply pipe 7 is connected. An annular tray 11 having a steam passage 10 is fixedly provided on the inner surface of the casing 1.
A ring-shaped weir plate 18 is provided on the inner peripheral edge of the pipe. Furthermore, the primary deaeration chamber 4 is provided with a vent pipe 9.

Inside the secondary degassing chamber 5, a cylindrical side wall 15 is vertically disposed downward from the periphery of the inner circumferential opening 2 of the partition wall 3 toward the inside of the secondary degassing chamber 5, and a gas-liquid contact device is installed inside the cylindrical side wall 15. 16 will be provided. As illustrated in FIG. 2, this gas-liquid contacting device 16 has a large number of trays 13 arranged vertically at intervals 14 so that the passages 12 form a staggered pattern, and an upper end opening 17 of the trays 13 is arranged in a staggered manner. It faces into the primary degassing chamber 4 so as to substantially coincide with the inner peripheral opening 2 of No. 3, and the lower end opening 19 is open to the secondary degassing chamber 5.

A heating steam introduction pipe 20 for deaeration is connected and opened in the secondary deaeration chamber 5, and a riser pipe 21 is provided in the partition wall 3 for communicating the secondary deaeration chamber 5 with the primary deaeration chamber 4. is provided so as to protrude upward from the upper surface of the partition wall 3 into the primary degassing chamber 4.

Therefore, from the heated steam introduction pipe 20 to the secondary deaeration chamber 5
A part of the heated steam for degassing initially supplied to the primary degassing chamber 4 passes through the gas-liquid contact device 16 in the secondary degassing chamber 5.
The other part is introduced into the gas-liquid contact part 1.
6, it can be directly introduced into the primary degassing chamber 4 through the riser pipe 21.

The number and total area of these riser pipes 21 are determined as desired, and the bottom of the secondary deaeration chamber 5 is connected to the deaerated water storage tank 22 via a downcomer pipe 23. , numeral 24 in the figure is a pressure equalizing pipe for communicating the inside of the secondary deaeration chamber 5 and the inside of the deaerated water storage dunk 22.

The water introduced into the header 8 through the water supply pipe 7 is atomized by the spray nozzle 6 and spreads throughout the primary degassing chamber 4, and a part of it is transferred to the tray 13 in the gas-liquid contact device 16. While the water that falls directly and accumulates, the water that flows down along the peripheral wall of the primary deaeration chamber 4 and the water that falls onto the top surface of the annular tray 11 overflows from the weir plate 18 in the form of a film and reaches the top surface of the partition wall 3 below. It flows down to the gas-liquid contact device 16 below the upper surface of the partition wall 3. The feed water thus accumulated in the tray 13 of the gas-liquid contacting device 16 further overflows from the tray 13, flows down the passage 12 in the form of a film as shown in FIG. 2, and accumulates in the lower tray. This process is then repeated as it flows downward.

On the other hand, a part of the heating deaeration steam initially introduced into the secondary deaeration chamber 5 from the steam introduction pipe 20 is transferred from the lower end opening 19 of the gas-liquid contact device 16 to the contact device 16.
passage 12 and spacing 14 between each tray 13.
The water rises and comes into contact with the water supply flowing down in the form of a film to be heated and degassed, and then rises into the primary degassing chamber 4 through the upper opening 17, and the other part flows into the gas-liquid contact device 16. without entering the primary degassing chamber 4 through the riser pipe 21, and mixing with the surplus steam still remaining after passing through the gas-liquid contact device 16,
It comes into contact with the atomized feed water ejected from the spray nozzle 6, heats the feed water to a high temperature, and degasses the water.

The feed water thus degassed twice in the gas-liquid contact devices 16 of the primary deaeration chamber 4 and the secondary deaeration chamber 5 accumulates at the bottom of the secondary deaeration chamber 5 as deaeration water.
The degassed water flows down through the downcomer pipe 23 into the deaerated water storage tank 22, while air, carbon dioxide, etc. separated from the water supply are discharged to the outside from the vent pipe 9.

In the above embodiment, the gas-liquid contact device 16 is of a tray type, but it goes without saying that other configurations may also be used, and the number of vapor branch ports and the total area can be arbitrarily set as desired.

In a deaerator consisting of a primary deaeration chamber 4 having a spray nozzle 6 as described above, and a secondary deaeration chamber 5 having a gas-liquid contact device 16 and to which heated steam for deaeration is first supplied. In the present invention, part of the heated steam is introduced into the primary deaeration chamber 4 via the gas-liquid contact device 16 in the secondary deaeration chamber 5, while the other part is introduced into the primary deaeration chamber 4 through the riser pipe 21. Since the steam is directly introduced into the primary degassing chamber 4, less of the steam consumed in the primary degassing chamber 4 flows into the primary degassing chamber 4 via the gas-liquid contact device 16. Since the amount of steam that passes through the liquid contact device 16 and enters the primary degassing chamber 4 is reduced, the flooding phenomenon cannot occur even if the steam passage in the gas-liquid contact device 16 is narrowed. , a part of the heated steam is transferred to the primary deaeration chamber 4 through the riser pipe 21.
By directly introducing the heated steam through the gas-liquid contact device 16, the deaeration efficiency within the primary deaeration chamber 4 can be improved compared to when all of the heated steam is introduced through the gas-liquid contact device 16.

In this case, the riser pipe 21 for directing a part of the heated steam in the secondary degassing chamber 5 to the primary degassing chamber 4 may be a mere communication hole bored in the partition wall 3 or a horizontal pipe. In this case, a part of the feed water flowing on the upper surface of the partition wall 3 toward the gas-liquid contacting device 16 flows into this communication hole or horizontal pipe and flows downward toward the secondary degassing chamber 5. As a result, a part of the supplied water performs a secondary deaeration effect in the gas-liquid contact device 16.
Since the water is bypassed without passing through the water, the deaeration of the bypassed water becomes inadequate and the deaeration performance deteriorates.

Moreover, the flow of the feed water flowing down from the communication hole or the horizontal pipe in this way obstructs the flow of heated steam rising toward the primary degassing chamber 4 through the communication hole or the horizontal pipe.

In this way, the flow of heated steam is obstructed by the feed water flowing down through the communication hole or the horizontal pipe, which means that the amount of heated steam directly introduced from the secondary deaeration chamber 5 to the primary deaeration chamber 4 is reduced. Since the amount of heated steam passing through the gas-liquid contact device 16 increases by this decrease, the flooding phenomenon becomes more likely to occur in the gas-liquid contact device 16. In contrast, in the present invention, as described above, the riser pipe 21 for directly guiding a part of the heated steam in the secondary deaeration chamber 5 to the primary deaeration chamber 4 is connected to the water supply flowing down from the primary deaeration chamber 4. , the gas-liquid contact device 1 in the secondary degassing chamber 5
4 from the upper surface of the partition wall 3 to the primary degassing chamber
It is formed so as to protrude inwardly and upwardly, and when the feed water jetted from the spray nozzle 6 into the primary degassing chamber 4 flows to the gas-liquid contact device 16 via the upper surface of the partition wall 3, one part of the feed water is Part is the riser pipe 2
1 to the secondary deaeration chamber 5 side, a part of the supplied water will not bypass the gas-liquid contact device 16, and will not flow down inside the riser pipe 21. There is no flow obstruction to the heated steam flowing upwards from the top. That is, the entire amount of water flowing from the primary degassing chamber 4 to the secondary degassing chamber 5 is transferred to the gas-liquid contact device 16.
Moreover, since there is no change in the amount of heated steam directly introduced into the primary degassing chamber 4 through the riser pipe 21, the secondary degassing chamber 5
The amount of heated steam directly introduced into the primary deaeration chamber 4 from
The ratio of the amount of heated steam flowing through the gas-liquid contact device 16 to the primary deaeration chamber 4 can be arbitrarily set by setting the passage area of the riser pipe 21, and
This ratio can be maintained constant and the gas-liquid contact device 16
This makes it possible to reliably prevent the amount of heated steam flowing into the primary degassing chamber 4 from fluctuating.

As described above, in the present invention, the inside of a closed casing is divided into an upper primary deaeration chamber and a lower secondary deaeration chamber by a substantially horizontal partition wall, and the primary deaeration chamber has an upper part. A spray nozzle for water supply is provided at the bottom, and an annular tray is provided at the bottom, while a gas-liquid contact device communicating with both the secondary deaeration chamber and the primary deaeration chamber is provided in the secondary deaeration chamber, and a heated steam introduction pipe is provided in the secondary deaeration chamber. In a deaerator with an opening, a part of the heated steam supplied into the secondary deaeration chamber is directly led to the primary deaeration chamber, where feed water is initially supplied, via a riser pipe. Since the amount of heated steam passing through the gas-liquid contact device is reduced, the occurrence of a flooding phenomenon in the gas-liquid contact device can be prevented.

Moreover, when directing a portion of the heated steam supplied into the secondary deaeration chamber through the riser pipe to the primary deaeration chamber, the riser pipe is used to separate the primary deaeration chamber from the secondary deaeration chamber. By protruding upward into the primary degassing chamber from the top surface of the substantially horizontal partition wall for guiding the water supplied to the primary degassing chamber to the gas-liquid contact device, the water from the primary degassing chamber to the secondary degassing chamber is The entire amount of feed water flowing into the degassing chamber can be passed through the gas-liquid contact device, and the amount of heated steam introduced directly from the secondary degassing chamber to the primary degassing chamber and the amount of heated steam passing through the gas-liquid contact device being The ratio of the amount of heated steam flowing to the air chamber can be set arbitrarily by setting the passage area of the riser pipe, and this ratio can be maintained constant, allowing the steam to pass through the gas-liquid contact device and to the primary deaeration chamber. This prevents fluctuations in the amount of heated steam flowing into the primary deaeration chamber via the riser pipe, which may cause a flattening phenomenon in the gas-liquid contact device or cause poor deaeration. It is possible to reliably prevent this from occurring.

Therefore, according to the present invention, a part of the heated steam supplied to the secondary deaeration chamber is directly introduced into the primary deaeration chamber which requires large consumption of heating steam, and a part of the heated steam supplied to the secondary deaeration chamber is directly introduced into the primary deaeration chamber, which requires a large amount of heating steam to be consumed. It is possible to pass the entire amount of feed water flowing into the secondary deaeration chamber through the gas-liquid contact device that performs secondary deaeration, and the amount of heated steam flowing from the secondary deaeration chamber through the gas-liquid contact device to the primary deaeration chamber is variable. The combination of these three factors makes it possible to significantly improve the deaeration performance of the deaerator as a whole.Moreover, the vapor passage of the gas-liquid contact device in the secondary deaeration chamber can be narrowed, and the riser pipe can be prevented. This combined with the fact that the deaerator can be built into the casing has the effect of significantly reducing the size and weight of the deaerator.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with FIG. 1 being a longitudinal sectional front view and FIG. 2 being a partially enlarged sectional view of the gas-liquid contact device. 1... Casing, 2... Opening, 3... Partition wall,
4... Primary deaeration chamber, 5... Secondary deaeration chamber, 6... Spray nozzle, 7... Water supply pipe, 8... Header,
10... Passage, 11... Annular tray, 16... Gas-liquid contact device, 20... Heated steam introduction pipe for deaeration, 2
1...Rise pipe.

Claims (1)

[Scope of utility model registration request] The inside of the closed casing is divided into an upper primary deaeration chamber and a lower secondary deaeration chamber by a substantially horizontal partition.
The primary deaeration chamber is provided with a water supply spray nozzle at the top and an annular tray at the bottom, while the secondary deaeration chamber is provided with air that communicates with both the secondary deaeration chamber and the primary deaeration chamber. In a deaerator which is provided with a liquid contact device and has a heated steam introduction pipe opened, the gas-liquid contact device is provided in a cylindrical side wall hanging downward from the partition wall toward the secondary degassing chamber, The degassing device is characterized in that the partition wall is provided with a riser pipe for communicating the secondary deaeration chamber with the primary deaeration chamber so as to protrude upward from the top surface of the partition wall into the primary deaeration chamber. Air.