JP3329732B2 - Distillation equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a distillation apparatus.

[0002]

2. Description of the Related Art Conventionally, when a plurality of distillation columns are combined and a product is obtained by distilling each component from a stock solution containing a plurality of components to obtain a product, if the distillation columns are separately constructed, the occupied area becomes large. Would. Further, in the side column type distillation apparatus, since it is necessary to control the distribution of steam between the respective distillation columns in order to adjust the pressure in each of the distillation columns, the respective distillation columns cannot be operated stably. .

[0003] Therefore, there has been provided a distillation apparatus which uses a Petriuk-type distillation column in which an inner cylinder is provided in an outer cylinder, and a stock solution is supplied into the inner cylinder to perform distillation. However, in this case, it is difficult to support the inner cylinder with respect to the outer cylinder, arrange a line by penetrating the outer cylinder, or attach a feed nozzle to the inner cylinder. Will be expensive. In addition, since the space between the line and the outer cylinder and the space between the feed nozzle and the inner cylinder cannot be sufficiently sealed, the efficiency of distillation in the distillation column is reduced.

[0004] Since the inner cylinder and the outer cylinder are arranged concentrically and the collecting section and the concentrating section have an annular structure, it is difficult to manufacture trays arranged in the collecting section and the concentrating section. become. Therefore, a distillation apparatus in which the inside is partitioned by a flat partition is provided (US Pat. No. 42305).
No. 33).

[0005] In this case, the distillation apparatus is supplied with a stock solution through an inlet pipe, and has a first concentrating section formed above the inlet pipe and a first collecting section formed below the inlet pipe. And a distillation unit connected to the upper end of the first distillation unit,
A concentration unit formed above the upper end, and a second distillation unit provided below the upper end and provided with a collection unit adjacent to the concentration unit of the first distillation unit via a partition. Connected to the lower end of the first distillation section, formed above the lower end, and formed adjacent to the recovery section of the first distillation section via a partition, and below the lower end. And a third distillation unit provided with a recovered recovery unit.

Accordingly, the cost of the distillation apparatus can be reduced, the efficiency of distillation can be increased, and the packing element can be easily manufactured.

[0007]

However, in the above-mentioned conventional distillation apparatus, in order to properly distribute the liquid descending from above to the concentration section of the first distillation section and the recovery section of the second distillation section. , The flow rate of the liquid supplied from the concentration section of the second distillation section to the concentration section of the first distillation section needs to be adjusted by an analyzer, a flow controller and a flow control valve, It is necessary to adjust the flow rate of the liquid supplied from the concentration section to the recovery section of the second distillation section by using a level sensor, a flow rate controller and a flow rate control valve.

In order to properly distribute the liquid descending from above to the recovery section of the first distillation section and the concentration section of the third distillation section, the flow rate of the stock solution supplied to the first distillation section is adjusted. Not only does it need to be adjusted by a flow controller and a flow control valve, but also the amount of product discharged between the first and second distillation sections needs to be adjusted by a level sensor, a flow controller and a flow control valve.

[0009] Then, the steam rising from below is removed to the first place.
In order to properly distribute to the recovery section of the distillation section and the concentration section of the third distillation section, the flow rate of steam supplied from the recovery section of the third distillation section to the recovery section of the first distillation section is measured by an analyzer and Not only must the flow control valve adjust the flow rate, but also the flow rate of the steam supplied from the recovery section of the third distillation section to the enrichment section of the third distillation section needs to be adjusted by the analyzer and the flow control valve.

As described above, in order to properly distribute the liquid and the vapor, it is necessary to dispose not only instrumentation equipment such as an analyzer, a flow controller, a flow control valve, and a level sensor, but also to install each instrumentation equipment. Since it is necessary to perform complicated control by operation, not only the size of the distillation apparatus is increased, but also the cost of the distillation apparatus is increased. The present invention can solve the problems of the conventional distillation apparatus, reduce the number of instrumentation, simplify the control, reduce the size, and reduce the cost. It is an object to provide a distillation apparatus.

[0011]

For this purpose, in the distillation apparatus of the present invention, a column main body, a partition that divides the inside of the column main body and forms a plurality of chambers adjacent to each other, and a feed nozzle are provided. A first distilling unit provided with an undiluted solution, a concentrating unit formed above the feed nozzle, and a collecting unit formed below the feed nozzle;
A concentrating unit connected to the upper end of the first distillation unit, formed above the upper end, and formed below the upper end, and adjacent to the concentrating unit of the first distillation unit via a partition A second distillation section having a recovery section to be connected to the first distillation section, and a lower end of the first distillation section, and formed above the lower end, and
A concentrating section adjacent to the collecting section of the first distillation section via an intermediate partition; and a third distillation section provided with a collecting section formed below the lower end.

The liquid descending from the concentrating section of the second distillation section is supplied to the condensing section of the first distillation section and the second liquid.
Are distributed at a distribution ratio set in advance based on the distillation conditions. Further, the pressure loss generated in the first distillation section and the pressure loss generated in the recovery section of the second distillation section and the pressure loss generated in the concentration section of the third distillation section are the descending liquid amounts caused by the liquid distribution. Are made equal according to the difference between

In another distillation apparatus of the present invention, the F factor in at least the first distillation section, the recovery section of the second distillation section, and the enrichment section of the third distillation section is determined by the amount of the liquid falling. It is set to a value that gives a pressure loss that is not affected. In still another distillation apparatus of the present invention, the F factor in at least the first distillation section, the recovery section of the second distillation section, and the concentration section of the third distillation section may be 1.0 to 1.5. It is.

[0014] In still another distillation apparatus of the present invention, the packing provided in the first distillation section, the recovery section in the second distillation section, and the concentrating section in the third distillation section are further provided. The packing to be arranged is selected according to the packing properties. In still another distillation apparatus of the present invention, each of the pressure losses is calculated based on the number of theoretical plates, the number of equilibrium theoretical plates per unit height, and the pressure loss per unit height. In still another distillation apparatus according to the present invention, the cross-sectional area of the first distillation section, the recovery section of the second distillation section, and the third
Is set in accordance with the rising steam amount.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a conceptual diagram of a combined distillation column according to a first embodiment of the present invention, and FIG.
FIG. 1 is a conceptual diagram of a distillation apparatus according to a first embodiment of the present invention. In the figure, reference numeral 10 denotes a combined distillation column, and the combined distillation column 10 includes a first section 11, a second section 12, a third section 13, a fourth section 14, a fifth section 15, a sixth section 16, It comprises a seventh section 17, an eighth section 18 and a ninth section 19.

In the fourth section 14, the fifth section 15 and the sixth section 16, the column main body of the combined distillation column 10 is connected to the first chambers 14A to 16A by plate-shaped partitions 22 to 24, respectively. 2nd room 1
4B to 16B, and the first chambers 14A to 16A and the second chambers 14B to 16B are adjacent to each other. Also,
The first distillation section 25 is provided by the first chambers 14A to 16A.
However, the second distillation section 26 is formed by the first section 11, the second section 12, the third section 13, and the second chamber 14B, and the second chamber 15B, 16B, the seventh section 17, the eighth section 18, and Third sections 27 are respectively formed by the nine sections 19.

The partitions 22 to 24 may be formed of a heat insulating material, or the insides of the partitions 22 to 24 may be evacuated to form a heat insulating structure. In this case, between the first chamber 14A and the second chamber 14B, between the first chamber 15A and the second chamber 15B, and between the first chamber 15A and the second chamber 14B.
Since the heat transfer between 6A and the second chamber 16B can be respectively reduced, the efficiency of distillation can be increased.

The fifth section 15 is disposed substantially at the center of the combined distillation column 10, and a feed nozzle 41 is formed in the first chamber 15A, and a side cut nozzle 42 is formed in the second chamber 15B. The first section 11 is disposed at the top of the combined distillation column 10, and the first section 11 is connected to a condenser 81, and a vapor outlet 43 and a reflux liquid inlet 44 are formed respectively. Further, a ninth section 19 is provided at the bottom of the combined distillation column 10,
In the ninth section 19, a bottoms outlet 45 and a steam inlet 46 are respectively formed to be connected to the evaporator 82.

In the combined distillation column 10 having the above structure, a mixture containing the components A to C is supplied to the feed nozzle 41 as a stock solution M. In addition, component A is obtained from component B,
Component B has a lower boiling point than component C. The combined distillation column 1
0, the condenser 81, the evaporator 82 and the like constitute a distillation apparatus. Further, the first chamber 14 disposed above the feed nozzle 41 in the first distillation section 25.
A forms the enrichment section AR1 and the first chamber 16A disposed below the feed nozzle 41 forms the recovery section AR2. In the second distillation section 26, the second section 12 connected to the upper end of the first distillation section 25 and disposed above the upper end forms the enrichment section AR3 by the first distillation section 25. The collection sections AR4 are respectively formed by the second chambers 14B disposed adjacent to the enrichment section AR1 below the upper end of the collection section AR1. Further, the concentrating unit AR5 is connected to the lower end of the first distillation unit 25 in the third distillation unit 27, and is provided above the lower end by the second chamber 16B disposed adjacent to the recovery unit AR2. However, the recovery sections AR6 are respectively formed by the eighth sections 18 disposed below the lower end of the first distillation section 25.

Thus, the upper end of the first distillation section 25 is connected to the center of the second distillation section 26, and the lower end of the first distillation section 25 is connected to the center of the third distillation section 27. Then, in the collection part AR2, the feed nozzle 41
The stock solution M supplied from the container descends, and vapors rich in the components A and B move upward, and the components B and C move downward as the concentration decreases.
And a liquid rich in components B and C is supplied from the lower end of the first distillation section 25 to the third distillation section 27.

Further, the liquids rich in the components B and C are:
It is heated in the third distillation section 27 to become a vapor rich in components B and C, and comes into contact with the stock solution M while rising in the recovery section AR2, and is rich in components A and B from the stock solution M. Generates steam. Subsequently, the vapors rich in the components A and B rise in the enrichment section AR1, and are supplied to the second distillation section 26 from the upper end of the first distillation section 25. Further, the vapor rich in the components A and B is supplied to the second distillation section 2
It is cooled and condensed in 6 to become a liquid rich in components A and B.

Then, a part of the liquid rich in the components A and B is refluxed to the concentrating section AR1, and is brought into contact with the vapor rich in the components A and B rising in the concentrating section AR1. In this way, vapors rich in components A and B can be supplied from the upper end of the first distillation section 25 to the second distillation section 26. In the recovery part AR6, the liquid rich in the components B and C descends, and generates vapor rich in the component B at the upper part and liquid rich in the component C at the lower part. Therefore, the liquid rich in the component C is discharged from the bottom outlet 45 as bottoms.

A part of the liquid rich in the component C discharged from the bottom outlet 45 is sent to the evaporator 82 and heated by the evaporator 82 to become a vapor rich in the component C. The vapor rich in component C is supplied from the vapor inlet 46 to the ninth section 19, and comes into contact with the liquid rich in components B and C while ascending in the ninth section 19 and the recovery section AR6. A vapor rich in component B is generated from the liquid rich in components B and C.

Subsequently, a part of the vapor rich in the component B is
The liquid rises in the enrichment section AR5 and comes into contact with the liquid rich in the component B from the second distillation section 26 at the upper end of the third distillation section 27 to become a liquid rich in the component B. The liquid rich in the component B obtained at the upper end of the third distillation section 27 is discharged from the side cut nozzle 42 as a side cut liquid, that is, a product.

On the other hand, the recovery section AR of the second distillation section 26
At 4, the liquids rich in components A and B descend, producing vapors rich in component A above and liquids rich in component B downward. In this way, the liquid rich in component B obtained at the lower end of the second distillation section 26 is supplied as a product to the side cut nozzle 42.
Is discharged from

Subsequently, the vapor enriched in the component A rises in the enrichment section AR3, is discharged from the vapor outlet 43 and is sent to the condenser 81, where it is condensed by the condenser 81 to the component A. It becomes a rich liquid. In this way, the vapors rich in components A and B are separated by the second distillation section 26 into a vapor rich in component A and a liquid rich in component B. The liquid is discharged from the top and condensed by the condenser 81 to become a liquid rich in component A, and the liquid rich in component B is discharged from the side cut nozzle 42 as a product. The liquid rich in components B and C is separated into a liquid rich in component B and a liquid rich in component C by the third distillation section 27, and the liquid rich in component B is cut as a product by side cutting. The liquid rich in component C discharged from the nozzle 42 is discharged from the bottom of the column.

Then, in order to increase the efficiency of distillation of the component A, the liquid rich in the component A is returned to the concentrating section AR3 from the reflux liquid inlet 44, and the components A and B rise in the concentrating section AR3. Contact with rich steam. The enrichment sections AR1, AR3, AR5 and the collection sections AR
2. AR4 and AR6 are fillings consisting of one node
Depending on the specific volatility between the components to be distilled, depending on the characteristics of the packing used, to secure the number of theoretical plates required for distillation, Can also be formed by a filling consisting of In addition, a distributor can be provided between nodes. Further, the feed nozzle 41 and the side cut nozzle 42 do not always need to be arranged at the same height.

In this way, the stock solution M can be separated into each component without using a plurality of distillation columns.
In addition, since it is not necessary to repeat heating and cooling in a plurality of distillation columns, it is not necessary to provide a large number of instrumentation equipment such as a condenser, an evaporator, and a pump. Therefore, not only the occupied area can be reduced, but also the usage amount and energy consumption of the utility can be reduced, and the cost of the distillation apparatus can be reduced.

It should be noted that the combined distillation column 10 has about 30 to 100 theoretical plates as a whole, and the fourth section 14 and the sixth section 16 each have about 5 to 30 plates. preferable. Meanwhile, a collector 54 and a channel type distributor 61 are provided in the third section 13, and the liquid collected by the collector 54 is distributed by the distributor 61 at a predetermined distribution ratio to the first chamber 14 </ b> A of the fourth section 14.
And the second chamber 14B.

The first chamber 15A of the fifth section 15
The collector 62 is located immediately above the feed nozzle 41 in FIG.
However, a tubular type distributor 63 is disposed immediately below, and the liquid collected by the collector 62 is:
Along with the stock solution M supplied via the feed nozzle 41, the sixth section 1 is distributed by the distributor 63.
6 is supplied to the first chamber 16A.

On the other hand, the second chamber 15B of the fifth section 15
, A chimney hat type collector 65 is disposed directly above the side cut nozzle 42, and a tubular type distributor 66 is disposed directly below the side cut nozzle 42, and the liquid collected by the collector 65 is discharged from the side cut nozzle 42 as a product. With distributor 6
6 to the second chamber 16 </ b> B of the sixth section 16.

Further, a collector 67 and a tubular distributor 68 are provided in the seventh section 17, and the liquid descending from the sixth section 16 is:
After being collected by the collector 67, it is supplied to the eighth section 18 by a distributor 68. By the way, in the present embodiment, the liquid that has descended upward, that is, from the second section 12 to the third section 13 is distributed to the first chamber 14A and the second chamber 14B of the fourth section 14. However, the distribution ratio depends on the type of the components of the stock solution M, the composition of the components of the stock solution M, the number of theoretical plates in the combined distillation column 10, and the purity (quality) required for the product.
Are set in advance based on distillation conditions such as

For this purpose, the distributor 61
Comprises a distributor (not shown) for distributing liquid in a direction perpendicular to the partition 22, and the first
The amount of liquid supplied above the chamber 14A (hereinafter referred to as “upper portion of the first chamber”) and the amount of liquid supplied above the second chamber 14B (hereinafter referred to as “upper portion of the second chamber”). The amount is to be different.

It should be noted that the product is a side cut nozzle 42
The amount of liquid supplied to the upper portion of the second chamber is larger than the amount of liquid supplied to the upper portion of the first chamber. When it is necessary to change the distillation conditions in order to obtain two or more types of products in the distillation apparatus, it is necessary to change the distribution ratio in accordance with the distillation conditions. Therefore, a plurality of the distribution units are provided, and the distribution ratio is different for each distribution unit. To this end, the liquid descending from the second section 12 is collected by the collector 54 and selectively supplied to the distributor 61 via the switching valves 83 and 84. For example, when obtaining a product having a purity of 99.98 [% by weight], the distribution ratio is set to 4: 6, and when obtaining a product having a purity of 99.999 [% by weight], the distribution ratio is set to 2: 8. . The load factor is changed to 50 to 100%.

As described above, since the liquid can be distributed at the optimum distribution ratio only by disposing the distribution section, a large number of analyzers, a flow controller, a flow control valve, a level sensor and the like for distributing the liquid can be provided. Not only is there no need to dispose instrumentation components, but there is no need to operate each instrumentation component to perform complicated control. Therefore, not only the size of the distillation apparatus can be reduced, but also the cost of the distillation apparatus can be reduced.

In designing the combined distillation column 10, the number of equilibrium theoretical plates per unit height in each chamber NTS
M [stage / m], HETP [m
m], F factor f [(m / s) / √ (kg /
m ³ )], pressure loss ΔP [mm
Hg / m] must be determined. Note that the F factor f is a parameter representing a real velocity taking the pressure of the vapor into consideration, where the superficial velocity is u and the vapor density is ρ [kg
/ M ³ ], then f = u√ (ρ). Here, the vapor density ρ is expressed by the pressure P [mmHg].
When the temperature is T [° K] and the number of moles is M, ρ = 273.2 · PM · 22.41 × 760 · T = PM / (62.36) · T .

By the way, when the liquid is to be lowered and the vapor is to be raised in the chamber in which the packing is disposed, a pressure loss occurs in the flow of the vapor due to the liquid descending in the chamber. In the present embodiment, the distributor 61 makes the amount of liquid supplied to the upper part of the first chamber different from the amount of liquid supplied to the upper part of the second chamber. One room 14A and second room 1
The flow rate of the liquid descending 4B, that is, the descending liquid amount is different from each other. As a result, the pressure loss of the first chamber 14A and the pressure loss of the second chamber 14B are different from each other, and the first chamber 14A and the second chamber 14B have different pressure losses.
The amount of steam that rises in B, that is, the amount of steam that rises is different from each other.

Therefore, the F-factor f is set so that the pressure loss is equal even if the amounts of liquid drops are different from each other. FIG. 3 is a diagram showing a result of performing a simulation of a pressure loss in the first embodiment of the present invention. In this case, a simulation was performed under the following conditions.

Lowering material: ethyl acetate (MW = 88.1) Operating pressure: normal pressure (760 [mmHg]) Operating temperature: 76 [° C.] Steam density: 3.0785 [kg / m ³ ] Liquid density: 900 [kg / m ³ ] Surface strength: 20 [dyn / cm] Type of filler A: BX packing (trade name: manufactured by Sumitomo Heavy Industries, Ltd.) Descending liquid amount: 5, 10, 15, 20, 25, 30 [m ³ /
m ² hr] Relationship between F factor f [(m / s) ｋｇ (kg / m ³ )] and ascending steam flow rate per unit sectional area [kg / m ² hr]: 0.5 3200 1.0 6300 1 5.5 9500 2.0 12600 2.5 15800 Thus, using BX packing as filling A,
When the F-factor f is changed from 0.5 to 2.5, as can be seen from the figure, when the F-factor f is from 0.5 to 1.5, the pressure loss does not change even if the amount of liquid drop changes. It turns out that it hardly changes.

Therefore, in the present embodiment, the second section 12, the fourth section 14, the sixth section 1
BX packing is used as the filling A in the sixth and eighth sections 18 so that the F factor f is 1.0 to 1.5. Therefore, the second section 12, the fourth
Since the pressure loss in the section 14, the sixth section 16 and the eighth section 18 becomes substantially constant, the pressure loss occurring in the first chambers 14A, 16A and the second chamber 14
B and 16B are equal in pressure loss.
As a result, the ascending vapor is not affected by the descending liquid, so that the vapor is evenly distributed and ascended. Note that the F factor f can be set to 0.5 to 1.0, but in that case, the cross-sectional area of the chamber increases as the substantial velocity decreases.

In addition, it is not necessary to dispose a large number of instruments for distributing steam, and it is not necessary to operate each instrument to perform complicated control. Therefore, not only the size of the distillation apparatus can be reduced, but also the cost of the distillation apparatus can be reduced. In addition, since the descent of the liquid in the combined distillation column 10 and the rise of the vapor can be smoothed, the occurrence of the channeling (liquid shortage) phenomenon in the packing A in each chamber can be prevented as much as possible. However, it is possible to prevent the occurrence of maldistribution (non-uniform liquid dispersion).

By the way, in the combined distillation column 10, since the partitions 22 to 24 are disposed in the fourth section 14, the fifth section 15, and the sixth section 16, the first chamber 14A and the second chamber 14 are provided. 14B, and the first room 1
A difference in pressure loss easily occurs between 6A and the second chamber 16B. Therefore, the design of the combined distillation column 10 is designed to prevent a difference in pressure loss between the first chamber 14A and the second chamber 14B and between the first chamber 16A and the second chamber 16B. A second embodiment of the present invention will be described.

FIG. 4 is a diagram showing the characteristics of the combined distillation column according to the second embodiment of the present invention, and FIG. 5 is a diagram showing the packing characteristics according to the second embodiment of the present invention. In this case, the first section 14A and the second section 14B of the second section 12, the fourth section 14 and the first section 16A and the second section 16B of the sixth section 16 are formed by using BX packing as the packing material A. Eight sections 18 used Melapak 350Y (trade name, manufactured by Sumitomo Heavy Industries, Ltd.) as filler B.

[0044] Here, the first chamber 14A, the pressure loss occurring at 16A and [delta] P _1, the second chamber 14B,
The pressure loss occurring at 16B is δP ₂ . The first chamber 14A, 16A and the second chamber 14B, each theoretical plates _{16B NTS i (i = 14A,} 16A, 14B,
16B), and the number of theoretical plates per unit height is NTS
M _i (i = 14A, 16A, 14B, 16B) [stage /
m], and the pressure loss per unit height is ΔP _i (i = 1
4A, 16A, 14B, 16B).

At this time, the pressure loss δP ₁ is as follows: δP ₁ = (NTS _14A / NTSM _14A ) · ΔP _14A +
(NTS _16A / NTSM _16A ) · ΔP _16A , and the pressure loss δP ₂ is δP ₂ = (NTS _14B / NTSM _14B ) · ΔP _14B +
(NTS _16B / NTSM _16B ) · ΔP _16B , so that each F factor f _i (i =
14A, 16A, 14B, 16B), and with reference to FIG. 5, the pressure loss ΔP _i per unit height corresponding to each F factor f _i and the number N of equilibrium theoretical stages per unit height.
When TSM _i [stage / m] is calculated, each theoretical stage number NTS _i is calculated.
Is set to a predetermined value, the pressure loss δP
₁ , δP ₂ can be set to δP ₁ ≒ δP ₂ .

In FIG. 5, each F factor f _i , each pressure loss ΔP _i, and each number of balanced theoretical stages NTSM _i
The values for each are not shown and are expressed in ranges. Next, a third embodiment of the present invention will be described. FIG. 6 is a diagram showing characteristics of the combined distillation column according to the third embodiment of the present invention, and FIG. 7 is a diagram showing packing characteristics according to the third embodiment of the present invention.

Second section 12 and Eighth section 1
8, using Melapak 250Y (trade name, manufactured by Sumitomo Heavy Industries, Ltd.) as filler C,
In each of the first and second chambers 14A and 14B of the fourth section 16 and the first and second chambers 16A and 16B of the sixth section 16, Merapak 250X (trade name: manufactured by Sumitomo Heavy Industries, Ltd.) was used as the filler D. In this case, since Melapak 250Y is used in the second section 12 and the eighth section 18, the flow of liquid and vapor in the combined distillation column 10 (FIG. 1) could be stabilized. Further, since the Merapack 250X is used for the first chamber 14A and the second chamber 14B of the fourth section 14 and the first chamber 16A and the second chamber 16B of the sixth section 16, even if the ascending steam amount is large, the pressure is increased. The effects on the losses δP ₁ and δP ₂ are small.

Here, for example, if the number NTS _i of each theoretical stage is NTS _14A = 14 [stage] NTS _16A = 13 [stage] NTS _14B = 12 [stage] NTS _16B = 7 [stage], the first chamber 14A , 16A, the pressure loss δP ₁ is: δP ₁ = (NTS _14A / NTSM _14A ) · ΔP _14A +
(NTS _16A / NTSM _16A ) · ΔP _16A = (14 / 2.2) × 0.8 + (13 / 2.0) × 4.
5 = 34.34 [mmHg], and the pressure loss δP ₂ generated in the second chambers 14B and 16B is δP ₂ = (NTS _14B / NTSM _14B ) · ΔP _14B +
(NTS _16B / NTSM _16B ) · ΔP _16B = (12 / 2.0) × 4.0 + (7 / 2.0) × 3.0 = 34.5 [mmHg]

Therefore, the pressure loss δP ₁ , δP ₂
To δP ₁ ≒ δP ₂ . Next, a fourth embodiment of the present invention will be described. FIG. 8 is a diagram illustrating characteristics of a combined distillation column according to the fourth embodiment of the present invention, and FIG. 9 is a diagram illustrating packing characteristics according to the fourth embodiment of the present invention.

In this case, the number of theoretical stages (NTS _14A + NTS _16A ) of the first chambers 14A, 16A and the second chambers 14B, 16B
Is effective when the theoretical plate number (NTS _14B + NTS _16B ) is different and the amounts of ascending steam are different from each other.
The section 12 is filled with the packing C, the first chambers 14A and 16A are filled with the packing D, and the second chambers 14B and 16B are filled with the packing A.
The filling B is arranged in the section 18.

As a result, the pressure loss δP ₁ generated in the first chambers 14A and 16A and the pressure loss δP ₁ in the second chambers 14B and 16A
The pressure loss δP ₂ generated in B can be set to δP ₁ ≒ δP ₂ . Next, when only selecting each packing A~D pressure loss [delta] P _1, can not be equal to [delta] P _2, the fifth embodiment of the present invention which is adapted to equalize the pressure loss [delta] P _1, the [delta] P ₂ The embodiment will be described.

FIG. 10 is a conceptual diagram of a main part of a combined distillation column according to a fifth embodiment of the present invention, and FIG. 11 is a sectional view of a main part of the combined distillation column according to the fifth embodiment of the present invention. .
In the figure, 113 is the third section, 114A-11
6A is a first chamber, 114B to 116B are second chambers, 117 is a seventh section, and 122 to 124 are intermediate partitions.

This embodiment is effective in the case where the rising steam amounts in the first chambers 114A and 116A and the rising steam amounts in the second chambers 114B and 116B are different from each other depending on the distillation conditions in the combined distillation column. . Therefore, the middle partitions 122 to 124 are eccentric, and in the present embodiment, the cross-sectional area S1 of the first chambers 114A and 116A is smaller than the cross-sectional area S2 of the second chambers 114B and 116B. S1: S2 = 3 : 7.

By the way, the rising steam amount in the first chambers 114A and 116A is V1, the rising steam amount in the second chambers 114B and 116B is V2, and the superficial velocity in the first chambers 114A and 116A is u1. Assuming that the superficial velocity in the second chambers 114B, 116B is u2, the superficial superficial velocity u1, u2 is: u1 = (V1 / S1) × 3600 [m / s] u2 = (V2 / S2) × 3600 [m / S], and the superficial velocities u1 and u2 can be changed by changing the cross-sectional areas S1 and S2.

As a result, the F of the first chambers 114A and 116A
Factors f _114A and f _116A and second chambers 114B and 116B
F _114B and f _116B can be changed, and the pressure loss ΔP _114A and ΔP _116A per unit height in the first chambers 114A and 116A and the pressure per unit height in the second chambers 114B and 116B. The losses ΔP _114B and ΔP _116B can be changed.

Therefore, in the present embodiment, the first chamber 11 is formed by making the sectional areas S1 and S2 different.
Pressure drop Δ per unit height in 4A, 116A
P _114A and ΔP _116A are made equal to pressure losses ΔP _114B and ΔP _116B per unit height in the second chambers 114B and 116B, and pressure losses δP ₁ and δP ₂ are made equal. Next, a sixth embodiment of the present invention will be described.

FIG. 12 is a conceptual view of a main part of a combined distillation column according to a sixth embodiment of the present invention, and FIG. 13 is a sectional view of a main part of the combined distillation tower according to the sixth embodiment of the present invention. .
In the figure, 213 is the third section, 214A-21
6A is a first chamber, 214B to 216B are second chambers, 217 is a seventh section, and 222 to 224 are middle partitions.

This embodiment is effective in the case where the amount of rising steam in the first chambers 214A and 216A and the amount of rising steam in the second chambers 214B and 216B are different from each other depending on the distillation conditions in the combined distillation column. . Therefore, the intermediate partitions 222 to 224 are eccentric, and in the present embodiment, the sectional area S1 of the first chambers 214A and 216A is made smaller than the sectional area S2 of the second chambers 214B and 216B. S1: S2 = 4 : 6.

The height of the packing in the first chamber 214A is made smaller than the height of the packing in the second chamber 214B.
The filling height in 16A is made larger than the filling height in the second chamber 216B. In each of the above embodiments, BX packing, Mela pack 250X, Mela pack 250Y, Mela pack 350Y are used as the filler, but CY packing, Mela pack 125X, Mela pack 125Y, Mela pack 170X, Mela pack 170Y,
Mela pack 2X, Mela pack 2Y, Mela pack 500
X, Merapack 500Y, and Merapack 750Y can also be used (all are trade names: manufactured by Sumitomo Heavy Industries, Ltd.).

The present invention is not limited to the above embodiment, but can be variously modified based on the gist of the present invention, and they are not excluded from the scope of the present invention.

[0061]

As described in detail above, according to the present invention, the tower main body, the partition which divides the inside of the tower main body and forms a plurality of chambers adjacent to each other, and the feed nozzle are provided. An undiluted solution is supplied, a first distillation unit including a concentrating unit formed above the feed nozzle, and a recovery unit formed below the feed nozzle, and connected to an upper end of the first distillation unit. An enrichment section formed above the upper end, and a second distillation section formed below the upper end and provided with a recovery section adjacent to the enrichment section of the first distillation section via a partition Connected to the lower end of the first distillation section, formed above the lower end, and the enrichment section adjacent to the recovery section of the first distillation section via a partition, and below the lower end. And a third distillation section having the formed recovery section.

Then, the liquid that has descended from the concentrating section of the second distillation section is supplied to the condensing section of the first distillation section and the second liquid.
Are distributed at a distribution ratio set in advance based on the distillation conditions. Further, the pressure loss generated in the first distillation section and the pressure loss generated in the recovery section of the second distillation section and the pressure loss generated in the concentration section of the third distillation section are the descending liquid amounts caused by the liquid distribution. Are made equal according to the difference between

In this case, the pressure loss generated in the first distillation section is equal to the pressure loss generated in the recovery section of the second distillation section and the concentration section of the third distillation section. The effect of the descending liquid is not added to the evaporating vapor. Thus, the steam is evenly distributed and rises. In addition, it is not necessary to dispose a large number of instruments such as an analyzer, a flow controller, a flow control valve, and a level sensor for distributing steam, and also to perform complicated control by operating each instrument. No need. Therefore, not only the size of the distillation apparatus can be reduced, but also the cost of the distillation apparatus can be reduced.

Further, since the descent of the liquid and the rise of the vapor in the combined distillation column can be smoothed, it is possible not only to prevent the occurrence of the channeling phenomenon in each packing but also to reduce Can be prevented from occurring. In another distillation apparatus of the present invention, at least the first distillation section,
The F factor in the recovery section of the second distillation section and the concentration section of the third distillation section is 1.0 to 1.5.

In this case, since the F factor is 1.0 to 1.5, the pressure loss hardly changes even if the amount of liquid drop changes. Therefore, the pressure loss generated in the first distillation section is equal to the pressure loss generated in the recovery section of the second distillation section and the concentration section of the third distillation section.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a combined distillation column according to a first embodiment of the present invention.

FIG. 2 is a conceptual diagram of a distillation apparatus according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a result of simulating a pressure loss in the first embodiment of the present invention.

FIG. 4 is a diagram showing characteristics of a combined distillation column according to a second embodiment of the present invention.

FIG. 5 is a view showing characteristics of a filler in a second embodiment of the present invention.

FIG. 6 is a diagram showing characteristics of a combined distillation column according to a third embodiment of the present invention.

FIG. 7 is a view showing characteristics of a filler in a third embodiment of the present invention.

FIG. 8 is a diagram showing characteristics of a combined distillation column according to a fourth embodiment of the present invention.

FIG. 9 is a view showing characteristics of a filler in a fourth embodiment of the present invention.

FIG. 10 is a conceptual diagram of a main part of a combined distillation column according to a fifth embodiment of the present invention.

FIG. 11 is a sectional view of a main part of a combined distillation column according to a fifth embodiment of the present invention.

FIG. 12 is a conceptual diagram of a relevant part of a combined distillation column according to a sixth embodiment of the present invention.

FIG. 13 is a sectional view of a main part of a combined distillation column according to a sixth embodiment of the present invention.

[Explanation of symbols]

22 to 24, 122 to 124, 222 to 224 Partition 25 First distillation unit 26 Second distillation unit 27 Third distillation unit 41 Feed nozzle AR1, AR3, AR5 Concentration unit AR2, AR4, AR6 Recovery unit

────────────────────────────────────────────────── ─── Continued on the front page Examiner Keiko Ogawa (56) References JP-A-9-299701 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B01D 3/00-3 / 42

Claims (6)

(57) [Claims] 1. A (a) tower body, (b) a partition that divides the inside of the tower body and forms a plurality of chambers adjacent to each other, and (c) a stock solution is supplied via a feed nozzle, A first unit including a concentrating unit formed above the feed nozzle and a collecting unit formed below the feed nozzle;
(D) connected to the upper end of the first distillation section, formed as an enrichment section above the upper end, and formed below the upper end, and the first evaporator section through a partition. (E) connected to the lower end of the first distillation section, formed above the lower end, and via a partition. And a concentrating section adjacent to the collecting section of the first distillation section, and a third distillation section having a collecting section formed below the lower end. The liquid descending from the concentration section is distributed to the concentration section of the first distillation section and the recovery section of the second distillation section at a distribution ratio set in advance based on distillation conditions. Pressure loss occurring in the distillation section of
The pressure loss generated in the recovery section of the second distillation section and the concentration section of the third distillation section is caused by the distribution of the liquid.
A distillation apparatus characterized in that it is made equal in accordance with the difference in the amount of falling liquid that occurs . 2. The method according to claim 1, wherein at least the first distillation section and the second distillation section
In the recovery section of the distillation section and the concentration section of the third distillation section
The distillation apparatus according to claim 1, wherein the factor is set to a value at which a pressure loss unaffected by the amount of liquid drop is obtained. 3. The at least one first distillation section and the second distillation section.
In the recovery section of the distillation section and the concentration section of the third distillation section
The distillation apparatus according to claim 1, wherein the factor is 1.0 to 1.5. 4. A packing disposed in the first distillation section,
And the concentration of the recovery section of the second distillation section and the concentration of the third distillation section.
The filling material arranged in the constriction section is selected according to the filling material characteristics.
The distillation apparatus according to claim 1, wherein 5. The distillation apparatus according to claim 1, wherein each of the pressure losses is calculated based on the number of theoretical plates, the number of equilibrium theoretical plates per unit height, and the pressure loss per unit height. 6. A cross-sectional area of the first distillation unit, the second
2. The distillation apparatus according to claim 1, wherein a ratio of the cross-sectional area of the recovery unit of the distillation unit to the cross-sectional area of the enrichment unit of the third distillation unit is set in accordance with the rising steam amount.