JPH0975602A - Liquid distributing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve dispersing property of a liquid in a liquid distributing apparatus to be installed in a packed tower, miniaturize the packed tower in which gas-liquid contact is carried out, and also miniaturize an air separating apparatus. SOLUTION: A liquid receiving plate 3 to receive liquid 1 which flows down from an upper part is installed, the liquid 1 which flows down from the liquid receiving plate 3 is led to a circular liquid receiving disk 6, another liquid 1' from a liquid supplying pipeline 13 is also led to the liquid receiving disk 6, the liquid is led to a first liquid distributing box 7 through a buffer box 5 installed in the liquid receiving disk 6, and a plurality of second liquid distributing boxes 9 having a large number of holes 10 are installed under the first liquid distributing box 7 to improve the dispersing property of liquid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid distribution device for a packed column containing a packing, and a structure for downsizing the packed column and a device when the liquid distribution device of the present invention is applied to an air separation device. Regarding the structure.

[0002]

As described in JP-A-5-184804, a conventional liquid distributor installed in a packed column of a distillation column has a structure in which a drop between upper and lower packing materials occurs. A collector for collecting the coming liquid, a collecting pipe for collecting the liquid collected by the collector, and a dispersion pipe having a plurality of holes which are communicated with the lower end of the collecting pipe and are uniformly arranged in the column cross section of the packed column. The structure consisting of is generally used, and a liquid head is used to uniformly disperse the liquid. Alternatively, as disclosed in Japanese Examined Patent Publication No. 6-77683, one using a substantially rectangular orifice type trough instead of the dispersion pipe is known. Furthermore, JP-A-6-285
As described in Japanese Patent No. 323, it is also proposed that a collector for collecting liquid and a liquid distribution box are integrated in order to keep the height of the packed column low.

[0003]

However, the prior art of the liquid distributor described above is not sufficient for a structure for reducing the height of the packed tower when installed in the packed tower. Alternatively, even if miniaturization has been achieved, it is not sufficient as a method for uniformly distributing liquid. For example, it is known that in order to sufficiently bring out the performance of the ordered packing in the packed column, it is essential to carry out uniform liquid dispersion at the initial stage. To achieve this, depending on the type of packing, liquid distributors have been proposed with several hundred downflow points per square meter of column area.
However, since the descending liquid inevitably causes a non-uniform flow while passing through the packing, the effective gas-liquid contact area per unit volume gradually decreases, and the rectification efficiency decreases. Therefore, in the conventional packed tower, the continuous filling height of the packing for gas-liquid contact is divided into a certain range, and the collector (collector) and the liquid distribution for dispersing the liquid again between the packing and the packing. The device was installed. On the other hand, the installation of conventional collectors and liquid distributors in packed columns creates a considerable penalty to the height of the packed column. That is, the space required for the collector and the liquid distributor has to be secured in the packed tower, which causes the height of the packed tower to be unnecessarily high. On an industrial scale packed column, the height of the space for installing the collector and the liquid distributor is required to be about 2 meters. Moreover, when another liquid needs to be introduced, the height of this space is further increased due to the piping equipment. A first object of the present invention is to improve the dispersibility of liquid and to provide a small-sized liquid distributor.

Further, it is an object of the present invention to reduce the size of the packed column and further the size of the air separation device by providing the packed column for gas-liquid contact with the liquid distributor of the present invention.

[0005]

A first object of the present invention is to provide a liquid receiving plate for receiving a liquid flowing down from above, and a weir plate having an opening for allowing a gas to rise up the liquid flowing down from the liquid receiving plate. Lead to a circular liquid tray, and also lead liquids from other liquid supply pipes to the liquid tray along the weir plate, and lead to the first liquid distribution box through the opening where the liquid provided in the liquid tray flows down, First
It is achieved by providing a plurality of second liquid distribution boxes each having a large number of holes provided at the bottom of the liquid distribution box. Preferably, the opening of the liquid tray, the first liquid distribution box, the second
By providing a buffer plate composed of a perforated plate or a wire net in the liquid inflow portion of the liquid distribution box, the uniform dispersion of the liquid is improved. Further, preferably, the liquid receiving plate is inclined so that the liquid is guided to the outer periphery of the circular liquid receiving tray, the opening provided in the circular liquid receiving tray is provided in the center, and a plurality of weir plates are provided on both sides of the opening. It is necessary to provide.

The second object is achieved by providing a small liquid distributor having a good liquid dispersibility in the lower column, upper column and argon column of the packed column or the double rectification column of the air separation unit.

[0007]

According to the above construction, the liquid that has flowed down is once collected in the liquid receiving tray and then flows down into the circular liquid receiving tray. on the other hand,
The liquid receiving plate is inclined so that the liquid is guided to the outer periphery of the liquid receiving tray. Accordingly, the liquid flows into the opening provided at the center of the liquid receiving tray after forming a gentle liquid gradient while swirling the outer periphery of the liquid receiving tray over a relatively long distance. Further, the liquid from another liquid supply pipe provided in the liquid receiving tray is also introduced into the liquid receiving tray, and similarly flows into the opening along the dam plate. If a perforated plate or a wire mesh buffer plate is provided in this opening, it flows into the first liquid distribution box at a more uniform flow rate due to the orifice effect.
The liquid flowing in through the opening then holds a suitable liquid head in the first liquid distribution box. Further, the liquid uniformly flows into the plurality of second liquid distribution boxes through the holes appropriately provided at the lower end of the first liquid distribution box, and while holding the appropriate liquid heads, through the plurality of holes provided at the bottom. Drops into the packing with a uniform liquid flow rate. A more uniform liquid flow rate can be achieved by providing the above-mentioned buffer plates at the inlets of the first liquid distribution box and the second liquid distribution box. On the other hand, in the liquid distributor of the present invention, since the liquid receiving plate, the liquid receiving tray, the first liquid distribution box and the second liquid distribution box are integrated, the height of the liquid distribution device can be reduced. . Therefore, in the liquid distribution device of the present invention, it is possible to avoid the drawbacks of the conventional device, improve the dispersibility of the liquid,
A small liquid dispenser can be provided. As a result, it is possible to reduce the size of the packed tower containing the packing.

The air separation device performs rectification separation of raw material air by means of a double rectification column consisting of a high-pressure column and a low-pressure column and an argon column, utilizing the boiling point differences of nitrogen, oxygen and argon.
Conventionally, trays were used for the rectification column, but it is possible to reduce the pressure loss in the rectification column by replacing them with structured packing (ordered packing) with low pressure loss per theoretical plate. Is publicly known. However, due to the limitation of the continuous filling height of the packing, it was necessary to install the collector and the liquid distributor in places, and the height of the rectification column itself was unnecessarily increased. By providing the liquid distribution device of the present invention in the rectification column of the air separation device, the rectification column or the air separation device can be downsized.

[0009]

FIG. 1 shows an embodiment of the present invention. FIG. 1 shows the configuration of the liquid distributor of the present invention. The liquid distributor 11 is provided in a packed column for gas-liquid contact, that is, for distillation, absorption and the like, and is generally used in a state in which packings are installed above and below. The liquid receiving plate 3 (only one side is shown) collects the liquid 1 descending from the upper packing,
It serves to guide the liquid 1 to the liquid receiving tray 6. Round liquid tray 6
Is provided with, for example, two dam plates 4 having a substantially crescent shape, and the liquid receiving tray 6 is fixed to the inner wall of the packed tower by welding or the like. The liquid 1 guided to the liquid receiving tray 6 flows along the weir plate 4 while maintaining a certain liquid head, and a rectangular first box having a rectangular buffer box 5 formed of a buffer plate provided in the center of the liquid receiving tray 6 is used. Liquid distribution box 7. Similarly, liquid 1 with other liquid composition
′ Is also introduced through the liquid supply pipe 13, flows along the barrier plate 4, and flows into the first liquid distribution box 7 through the buffer box 5.
The buffer box 5 is composed of a perforated plate, a wire mesh, or the like, and is a kind of resistor for rectifying the turbulence of the inflowing liquid and keeping the flow rate of the liquid flowing into the first liquid distribution box 7 constant. Buffer box 5
The liquid 1 and the liquid 1 ′ that have flowed in from the first liquid distribution box 7 are maintained at a predetermined distance from the plurality of holes 8 provided at the bottom with respect to the column cross section of the packed column while maintaining the liquid head. Is divided into a plurality of second liquid distribution boxes 9 provided so as to maintain the temperature. The second liquid distribution box 9 has a large number of holes 10 provided below the distribution box, and has a structure capable of performing uniform liquid distribution while having an appropriate liquid head. On the other hand, the gas 2 that has risen from the lower filling material rises through the gap of the second liquid distribution box 9 and the space of the dam plate 4. Although the liquid receiving plate 3 is shown only on one side for convenience in this embodiment,
In the actual device, two liquid receiving plates are required. That is,
The gas 2 rises through the space 12 between the dam plate 4 and the liquid receiving plate 3. FIG. 2 shows a convenient cross-sectional surface of an embodiment of the liquid distributor. The liquid distributor 11 is provided between the packing 20 and the packing 20, and the liquid tray 6 is fixed to the tower wall of the packed tower 21 by welding or the like. Further, the liquid receiving plate 3 is fixed to the dam plate 4 by providing a space 12 so that the liquid from the upper filling material 20 does not directly short-pass to the lower filling material.
Therefore, the projected area of the liquid receiving plate 3 needs to be slightly larger than the opening area of the dam plate 4. Also, the liquid supply pipe 1
3 has a structure in which a liquid 1 ′ having another liquid composition is supplied.

Therefore, according to the present embodiment, the liquid 1 that has flowed down is once collected by the liquid receiving plate and then flows down into the circular liquid receiving tray 3. Next, the liquid 1 forms a gentle liquid gradient while swirling around the outer periphery of the dam plate 4 for a relatively long distance, and then flows into the opening provided in the center of the liquid receiving tray. Similarly, the liquid 1 ′ also flows into the opening of the liquid receiving tray after forming a gentle liquid gradient while swirling around the outer periphery of the dam plate 4 for a relatively long distance. If a buffer box 5 made of a perforated plate, a wire mesh or the like is provided in this opening, it flows into the first liquid distribution box 7 at a uniform flow rate due to the orifice effect. The liquid 1 and the liquid 1 ′ that have flowed in from the buffer box 5 are rectified by the buffer plate 30 so that the liquid turbulence is rectified, and the first liquid distribution box 7 holds an appropriate liquid head. Further, the liquid 1 and the liquid 1 ′ uniformly flow into the plurality of second liquid distribution boxes 9 through the buffer plates 31 from the holes appropriately provided at the lower end of the first liquid distribution box 7, and the appropriate liquid heads are provided. While maintaining the flow rate, a uniform liquid flow rate is applied to the filler 20 through a plurality of holes provided at the bottom. The buffer plate can be easily manufactured from a suitable perforated plate or a wire mesh like the buffer box. On the other hand, in the liquid distributor 11 of the present invention, since the liquid receiving plate 3, the liquid receiving tray 6, the first liquid distributing box 7, the second liquid distributing box 9 and the liquid supply pipe 13 are integrated, the liquid distributing device 11 is integrated. The height of can be lowered. The height of the liquid dispenser of the present invention on an industrial scale is about 1
m. Therefore, the liquid dispensing apparatus of the present embodiment has the effects of avoiding the drawbacks of the conventional apparatus, improving the dispersibility of the liquid, and providing a small-sized liquid dispensing apparatus.
As a result, there is an effect that it is possible to reduce the size of the packed column containing the packing.

An embodiment of the air separation device of the present invention is shown in FIG. Low pressure column as a typical system of air separation device,
Take a three-column distillation system of a high pressure column and a crude argon column as an example. The compressed, purified and cooled feed air 43 is introduced into the bottom of the high pressure column 22 located at the bottom of the double rectification column. The gas that has risen in the high-pressure column 22 is condensed in the heat exchanger 23 and becomes the reflux liquid in the column. Liquid nitrogen from the top 46,
Impure liquid nitrogen 45 from the intermediate stage and liquid air 44 rich in oxygen from the bottom are sent to the upper low pressure column 24 through a supercooler separately provided. A part of the liquid air is branched on the way from 47 and is sent to the condenser 26 of the crude argon column through 50. Liquid nitrogen 49, impure liquid nitrogen 48 and liquid air 5 as reflux liquid for the low pressure column 24 installed at the upper part of the double rectification column.
1 is introduced from the high-pressure tower 22 via a subcooler provided separately. The air, which is obtained by inserting a part of the raw material air and sending it to the turbine, is introduced into the low pressure column 24 through the cooled 52 together with the air 56 evaporated in the condenser 26 of the crude argon column. The liquid descending in the low-pressure column 24 is the heat exchanger 2
In 3, the heat is exchanged with nitrogen in the high-pressure column to evaporate and become a rising gas in the column. Product oxygen gas 59 from the upper part of the bottom liquid reservoir of the low pressure column 24, product nitrogen gas 57 from the top part, and impure nitrogen gas 58 from the middle stage are rectified and separated in the low pressure column 24 and discharged to the outside. Oxygen gas containing a slight amount of argon is inserted from the intermediate stage of the low-pressure column 24 and sent to the bottom of the crude argon column 25 through 54. The gas that has risen in the crude argon column 25 exchanges heat with liquid air in the condenser 26 to be condensed and becomes the reflux liquid in the column. Part of the ascending gas is sent to the argon refining process through 61 as crude argon gas. The liquid descending in the crude argon column 25 is returned to the low pressure column 24 from the bottom via 55. Such tower tanks and connecting pipes are installed by filling a cold insulation material in a cold insulation tank 62 with a perlite door. The high-pressure column 22 and the low-pressure column 2 are applied to the ordered packing for gas-liquid contact as a rectification element.
4 and the crude argon column 25 are possible, but in the present embodiment, the ordered packing 20 is built in each column. Further, the liquid distribution device 11 of the present invention is built in each of the columns into which the liquid flows or merges, and in particular, in the upper column 24, the rectification region is divided into five because of the process. A single liquid distributor 11 is provided. The uppermost liquid distribution device 11 of the upper column 24 and the liquid distribution device 11 of the crude argon column do not require liquid supply piping. Since the height of the liquid distributor of the present invention is about half (about 1 m) of the conventional example, the height of the upper tower can be suppressed to about 5 m lower. Since the height of the upper tower of the industrial-scale air separation device is about 30 m to 40 m, it is very effective in reducing the height of the rectification tower. Furthermore, in the case of the crude argon column 25, the theoretical plate number required for rectification reaches from 40 to a maximum of 200 plates. In the air separation apparatus, the HETP of the ordered packing for gas-liquid contact, that is, the height per theoretical plate is a known value of about 200 mm. When 200 theoretical plates are provided, the height of the packing material reaches 40 meters, so applying the liquid distributor according to the present invention instead of the conventional collector and liquid distributor reduces the height of the rectification column. It has a great effect. Further, the reduction of the amount of piping material and the height of the cold storage tank have a great effect on downsizing of the entire air separation device.

[0012]

According to the present invention, it is possible to avoid the drawbacks of the conventional device, improve the dispersibility of the liquid, and provide a small liquid distribution device. As a result, there is an effect that it is possible to achieve a compact packed tower having a packed packing. Further, by providing the packed tower of the present embodiment in the air separation device, there is an effect that it can contribute to downsizing and cost reduction of the device.

[Brief description of drawings]

FIG. 1 is a structural diagram of a liquid distribution device showing an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a liquid dispenser showing an embodiment of the present invention.

FIG. 3 is a block diagram showing an embodiment in which the liquid distributor of the present invention is used in an air separation device.

[Explanation of symbols]

1 ... Liquid, 1 '... Liquid, 2 ... Gas, 3 ... Liquid receiving plate, 4 ... Dam plate, 5 ... Buffer box, 6 ... Liquid receiving tray, 7 ... First liquid distribution box, 8
... hole, 9 ... second liquid distribution box, 10 ... hole, 11 ... liquid distribution device, 13 ... liquid supply pipe, 20 ... packing material, 22 ... lower tower, 24 ... upper tower, 25 ... crude argon tower, 30 , 31 ... Buffer plate.

Claims (5)

[Claims] 1. A filler, which is provided above a filling material or in the middle of the filling material, collects liquid flowing down from above and distributes the liquid to the filling material below, and allows gas from below to pass upward. In the liquid distributor, a liquid receiving plate for receiving the liquid, a substantially circular liquid receiving tray having a weir plate having at least one opening, and another liquid supply pipe provided in the liquid receiving tray, and at least one of the liquid receiving trays is provided. A first liquid distribution box having holes at the bottom for collecting the liquid flowing down from one opening and distributing the liquid; and a first liquid distribution box having a plurality of holes provided at the bottom of the first liquid distribution box at the bottom. A liquid distribution apparatus comprising a plurality of liquid distribution boxes (2). 2. The liquid distribution according to claim 1, wherein at least a buffer plate is provided at the opening of the liquid receiving tray, the first liquid distribution box, and the liquid inflow portion of the second liquid distribution box. apparatus. 3. The liquid distribution apparatus according to claim 1, wherein the buffer plate is a porous plate or a wire mesh. 4. A rectification column for separating at least one liquid component, wherein the rectification column is a gas-liquid via a packing between a gas having an upflow and a liquid having a downflow. In a rectification column for contact, at least one liquid distribution device according to claim 1 is provided in the rectification column. 5. An air separation device comprising the packed tower according to claim 4 in an air separation device.