KR100626678B1 - A Fractionation System Using Divided Wall Distillation Column with Prefractionator and Postfractionator - Google Patents

Abstract

The present invention is a distillation apparatus consisting of a main tower, a pretreatment tower and a main tower or a main tower and a post-treatment tower, wherein a space formed by installing one or two dividing walls in the main tower serves as a pretreatment tower or a main tower or a post-treatment tower. The dividing wall is characterized in that the distillation curve of the space that functions as the main column and the after-treatment column is similar to the equilibrium distillation curve, so that fractional distillation is possible while significantly reducing the energy used. A fractional distillation apparatus using a thermal combined distillation column system.

Therefore, the distillation apparatus of the present invention can constitute a new process by the design method proposed in the present invention, in particular, the distillation apparatus of the present invention, unlike the existing thermal complex distillation system of one or two distillation column of three Since the same function as the installation of the distillation column, the energy efficiency can be reduced, as well as the number of distillation columns can be reduced.

Split Wall, Thermal Complex Distillation Column, Pretreatment Tower, Main Tower, Aftertreatment Tower, Three-Component Distillation

Description

A Fractionation System Using Divided Wall Distillation Column with Prefractionator and Postfractionator             

1 is a schematic diagram of a distillation apparatus using a conventional heat combined distillation column.

Figure 2 is a schematic diagram of a distillation apparatus using another conventional thermal combined distillation column.

Figure 3 is a schematic diagram of a distillation apparatus using a thermal complex distillation column consisting of a conventional pretreatment tower, main tower and after-treatment tower.

Figure 4 is a schematic diagram of a distillation apparatus using a thermal complex distillation column having two dividing walls are installed in the main column according to the present invention.

Figure 5a and Figure 5b is a schematic diagram of a distillation apparatus using a thermal complex distillation column consisting of a main tower and a post-treatment tower is installed with one partition wall in another embodiment according to the present invention.

Figure 6 is a schematic diagram of a distillation apparatus using a heat-comprising distillation column consisting of a main tower with a pretreatment tower and one dividing wall in another embodiment according to the present invention.

Figure 7 is a graph showing the liquid composition distribution of the distillation system using a distillation column according to the present invention.

8 is an enlarged graph of the aftertreatment column composition distribution in the liquid composition distribution of FIG.

* Explanation of symbols in main part of drawing

113: pretreatment tower 121, 122, 123: main tower

132: after-treatment towers 141, 142, 143: condenser

151, 152, 153: re-combing 161, 162, 163: first dividing wall

171: second dividing wall F: raw material

B: High boiling point product D: Low boiling point product

S: Medium boiling point product NRU: Top of the pylon

NR: Mid end of pylon NSL: Bottom of pylon

NRR: middle stage of aftertreatment tower NRF: middle stage of aftertreatment tower

The present invention is a distillation apparatus used to separate each component from the mixture of the three components obtained in the petroleum refining and petrochemical process, each space is formed by installing one or two partition walls in each main column Fractionation using a heat-distillation column system with a dividing wall, which allows three distillation towers to function as pre-treatment towers or main towers or after-treatment towers, thereby simplifying the facilities of the distillation unit and saving energy. It relates to a distillation apparatus.

Conventionally, a distillation process for separating low-boiling benzene and toluene from an aromatic hydrocarbon mixture obtained from a naphtha reforming reactor employs a distillation column using two distillation columns as shown in FIG. 1. In (11), benzene (D), which is the lowest boiling point component, is separated, and toluene (S) and the high boiling point mixture (B) are separated in the second column (21). As such, the general distillation method used in the current petrochemical plant has a problem that energy consumption is high because the distillation column efficiency is low because the distillation curve of the system is different from the equilibrium distillation curve.

The inventors of the present invention, a patent application 2002-05619, which is selected as a solution for solving the above problems, uses only a distillation apparatus composed of two distillation columns as shown in FIG. 2. ) And the main tower 22 is composed of only one each, the main tower 22 is introduced into the upper end of the low boiling point component (D ') flowing through the upper portion of the pretreatment tower 12, the pretreatment to the lower end Since the high boiling point component (B ') flowing out through the lower part of the tower 12 is introduced, that is, three components are classified using only one pretreatment tower 12 and one main tower 22. Since the distillation apparatus produces all three products of the high boiling point product, the low boiling point product and the intermediate boiling point product in the main column 22, the distillation efficiency is low. This can be explained by the fact that the distillation curve of the pylon is different from the equilibrium distillation curve. This is because it is very difficult to obtain a complete equilibrium distillation curve that satisfies all three product compositions.

In order to solve the above problems, the present inventors have previously applied for 2004-57444, which adds a post-treatment tower 33 to a distillation apparatus composed of a pre-treatment tower 13 and a main column 23, as shown in FIG. By designing the main tower 23 and the aftertreatment tower 33 to have a distillation curve similar to the equilibrium distillation curve, the tower distillation efficiency can be increased and the amount of energy used can be significantly reduced, whereas the distillation curve Since the apparatus needs to install three distillation columns, there was a problem in that the equipment cost of the distillation apparatus is high.

Therefore, the present invention is to solve the above problems, since the space formed by installing one or two partition walls in the main column is utilized as a space capable of functioning as a pre-treatment tower or a main tower or a post-treatment tower. A dividing wall, which has the same effect as a distillation apparatus composed of a distillation column and is designed to have a distillation curve similar to an equilibrium distillation curve in the space of a distillation column that functions as a main column and a aftertreatment column. It is an object of the present invention to provide a fractional distillation apparatus using a thermal combined column system.

In particular, another object of the present invention is to reduce the number of distillation towers by utilizing the space formed by installing one or two dividing walls in the distillation column of the main column as a space capable of functioning as a pretreatment column or a main tower or aftertreatment column. The present invention provides a fractional distillation apparatus using a thermally-coupled distillation column system having a partition wall, which can reduce energy consumption and reduce equipment costs.

The present invention in the distillation apparatus consisting of the main tower or pretreatment tower and the main tower or main tower and the after-treatment tower, the space formed by installing one or two dividing walls in the main column is a function of the pre-treatment tower or main tower or after-treatment tower. The dividing wall is characterized in that the distillation curve of the space that functions as the main column and the after-treatment column is similar to the equilibrium distillation curve, so that fractional distillation is possible while significantly reducing the energy used. A fractional distillation apparatus using a thermal combined distillation column system.

As described above, the heat-comprising distillation column system having a dividing wall according to the present invention aims at improving the tower efficiency of a distillation system for a three-component mixture, and the system has high efficiency by installing one or two dividing walls in the main column. It has the same effect as that consisting of three distillation towers to form a space that functions as a pretreatment tower, a main tower and a aftertreatment tower having a liquid composition distribution similar to the equilibrium distillation system. The system designed for verifying the performance of the proposed system was evaluated using program simulation for distillation column design.

As an example of the fractional distillation method according to the present invention as described above, three components of BTX are mixed in a mixture of benzene, toluene, and xylene (hereinafter referred to as 'BTX'). Can be produced as a product. The number of components is three, but first, according to the boiling point and content, two groups of low boiling point components and high boiling point components are first classified into pretreatment operations in the first space of the pretreatment column or the main column which functions as the pretreatment tower, and then the main tower and The final product is produced by using the second space or the third space that serves as the aftertreatment tower.

Hereinafter, the configuration of a fractional distillation apparatus using a heat-comprising distillation column system having a dividing wall in the main column according to the present invention will be described in more detail with reference to the accompanying drawings.

As a first embodiment, a distillation apparatus using a thermal combined distillation column having two dividing walls according to the present invention installed in a main column is shown in FIG.

The condenser 141 is provided at the upper part and the reboiler 151 is installed at the lower part, respectively, and the first space ① and the second space are formed by two first and second partition walls 161 and 171 installed therein. (②) and the third column (③) is formed of the main column 121,

 The low boiling point component (D ') and the high boiling point component (B') separated from the mixture raw material (F) in which the three components are mixed into the intermediate stage (NR) of the first space (①) of the main tower (121) are separated. The low boiling point product (D) at the uppermost end (NRU) of 121, the high boiling point product (B) and the middle boiling point mixture component (S ') at the lowermost end (NSL) of the main column 121 are formed in the third space (③). The intermediate boiling point (NR) is produced as an intermediate boiling point product (S), respectively.

Some of the low boiling point component (B ') and the high boiling point component (D') separated in the first space (①) are introduced into the second space (②) again and distilled again, and then some of the low boiling point components (D) Produced as a high boiling point product (B), the remaining low boiling point component (B ') and the high boiling point component (D') is introduced into the third space (③) and re-distilled again, and then part of the low boiling point product (D) ) And the high boiling point product (B), and the rest of the intermediate boiling point mixture component is produced through the intermediate stage (NR) as the intermediate boiling point product (S), respectively.

At this time, a part of the low boiling point component (B ') and the high boiling point component (D') separated in the first space (①) is not introduced only into the second space (②), but also a small amount flows into the third space (③). .

As a second embodiment, a distillation apparatus using a heat-comprising distillation column composed of a main column and a post-treatment column having one dividing wall is shown in FIG. 5A,

The condenser 142 is provided at the upper part and the reboiler 152 is installed at the lower part, and the main tower 122 having the first space ① and the second space ② formed by the first dividing wall 162 therein. ) And the post-treatment tower 132 for purifying the intermediate boiling point mixture components (S ', S ") introduced from the main column 122,

The low boiling point component (D '), the high boiling point component (B'), and the third mixture of the three components mixed into the intermediate stage (NR) of the first space (①) of the main column 122 are introduced and separated. The low boiling point component (D ') and the high boiling point component (B') partially introduced into the second space (②) from the first space (①) are redeposited and the low boiling point product (D) at the top end (NRU) of the main column 122. , Intermediate boiling point mixture components S 'and S "which are respectively produced as the high boiling point product B at the lowermost end NSL of the main column 122 and introduced into the aftertreatment tower 132 in the second space ②. ) Is purified and a part is produced in the middle boiling point (S) at the intermediate stage (NRR) of the after-treatment tower 132, the remaining liquid flow rate (L _s ) and gas phase flow rate (V _s ) is the main column 122 ) To reflux.

As Example 3, the distillation apparatus of FIG. 5B is the same as the distillation apparatus of FIG. 5A.

The condenser 142 is provided at the upper part and the reboiler 152 is installed at the lower part, and the main tower 122 having the first space ① and the second space ② formed by the first dividing wall 162 therein. ) And the post-treatment tower 132 for purifying the intermediate boiling point mixture components (S ', S ") introduced from the main column 122,

The low boiling point component (D '), the high boiling point component (B'), and the third mixture of the three components mixed into the intermediate stage (NR) of the first space (①) of the main column 122 are introduced and separated. The low boiling point component (D ') and the high boiling point component (B') partially introduced into the second space (②) from the first space (①) are redeposited and the low boiling point product (D) at the top end (NRU) of the main column 122. , The high boiling point product (B) at the bottom end (NSL) of the main column 122, the middle boiling point product (S) is produced at the middle end (NR) of the main tower 122, and post-processing from the second space (②) After the intermediate boiling point mixture components S ′ and S ″ introduced into the tower 132 are purified, the total liquid phase flow rate L _s and the gas phase flow rate V _s are returned to the main column 122.

The distillation apparatus of Example 3 is produced in the middle stage (NR) of the main tower 122, unlike the middle boiling product (S) in the distillation apparatus of Figure 5a is produced in the intermediate stage (NRR) of the after-treatment tower (132) , Aftertreatment tower 132 is only responsible for the purification of the intermediate boiling point mixture components (S ', S ") transferred from the main tower (122).

As a fourth embodiment, a distillation apparatus using a heat combined distillation column composed of a pretreatment tower and a main column provided with one dividing wall is illustrated in FIG.

 A pretreatment tower 113 into which the mixture raw material F in which the three components are mixed is introduced;

A condenser 143 is provided on the upper part and a reboiler 153 is provided on the lower part, and the main tower 123 in which the first space ① and the second space ② are formed by the first dividing wall 163 therein. ),

The low boiling point component (d) and the high boiling point component (b), in which the mixture raw material (F) mixed with the three components are introduced and separated into the intermediate stage (NRF) of the pretreatment tower (113), are formed in the first space ( ①) and the second boiling point (②) and then distilled again so that the low boiling point component (D ') is the low boiling point product (D) and the high boiling point component (B') at the top end (NRU) of the main tower (123). At the lowest end (NSL) of 123, the high boiling point product (B) and the intermediate boiling point mixture component are produced at the middle boiling point (S) at the middle end (NR) of the second space (②).

At this time, the low boiling point component (D ') and the high boiling point component (B') separated in the first space (①) are partially distilled into the second space (②) and then re-distilled.

The lengths of the first dividing walls 161, 162, 163 and the second dividing walls 171 installed in the main column 121 are distilled from the first, second, and third spaces (①, ②, ③), respectively. The length is determined by the number of stages calculated by the curve.

In the above embodiment, the low boiling point component (D ') passes through the top (NRU) of the main tower (121, 122, 123) and the condenser (141, 142, 143), and part of the low boiling point product (D) is produced. , And the rest is refluxed to the upper part of the main tower (121, 122, 123) at the liquid phase flow rate (L _D ), and the high boiling point component (B ') and the lowest end (NSL) of the main tower (121, 122, 123) After passing through the reboilers 151, 152, 153, a part is produced as the high boiling point product B, and the remainder is refluxed back to the bottom of the main towers 121, 122, 123 at a gaseous flow rate V _B.

Looking at the role of the pre-treatment tower 113, the first space (①), the second space (②), the third space (③) and the after-treatment tower 132 described in each embodiment as follows. .

First, the pretreatment tower 113 separates the mixture raw material (F) mixed with the three components supplied from the raw material supply stage (NRF) into a low boiling point component (d) at the top and a high boiling point component (b) at the bottom, respectively. A low boiling point component (d) to the upper pretreatment tower connection stage of (123), and serves to introduce a high boiling point component (b) to the lower pretreatment tower connection stage.

At this time, since a part of the liquid L ₃ generated in the upper portion of the first space ① is transferred to the upper portion of the pretreatment tower 113, it is not necessary to install a cooler in the pretreatment tower 113, and Since a portion of the steam (V ₃ ) generated in the lower portion is transferred to the lower portion of the pretreatment tower 113, it is not necessary to install a reboiler in the pretreatment tower 113.

Second, the first space ① separates the mixture raw material F of three components introduced into the middle stage NR of the main towers 121 and 122 into a low boiling point component (D ') and a high boiling point component (B'). Afterwards, a portion thereof is passed through the top end (NRU) of the main tower (121, 122) and the condenser (141, 142), the low boiling point product (D), and the bottom end (NSL) of the main tower (121, 122) and reboiler ( 151, 152 is produced as a high boiling point product (B), and the rest serves to introduce the first dividing walls (161, 162) into the second space (②) through the upper and lower ends.

Third, the second space ② is divided into Example 1, Example 2, 3 and Example 4 and described,

Iii) In case of the first embodiment, the second space (②) is redistilled by the low boiling point component (D ') and the high boiling point component (B') respectively introduced through the upper and lower portions of the first dividing wall (161). D ') and the high boiling point component (B'), and a part of the low boiling point product (D) and the lowermost end of the main tower 121 through the top end (NRU) and the condenser 141, respectively. Through the NSL and the reboiler 151 to produce a high boiling point product (B), the rest serves to introduce the second dividing wall 171 into the third space (③) through the upper and lower ends. .

Ii) In the case of Examples 2 and 3, the second space ② is redistilled by the low boiling point component D 'and the high boiling point component B' respectively introduced through the upper and lower portions of the first dividing wall 162, thereby again lowering the boiling point. After separating into component (D ′) and high boiling point component (B ′), a portion of the low boiling point product (D) and the main tower 122 are respectively passed through the top end (NRU) of the main column 122 and the condenser 142. The middle boiling point mixture component S ′ produced through the lowermost end NSL and the reboiler 152 and introduced into the aftertreatment tower 132 in the second space ② of the second embodiment. , S ″) is purified and partly produced as intermediate boiling product S at the intermediate stage (NRR) of aftertreatment tower 132, and the intermediate boiling mixture components (S ′, S ″) of Example 3 In the middle stage (NR) of the two spaces (②) serves to produce the intermediate boiling point product (S).

Iv) In case of the fourth embodiment, the second space ② is redistilled by the low boiling point component D 'and the high boiling point component B' respectively introduced through the upper and lower portions of the first dividing wall 163, and then again the low boiling point component. After separating into (D ′) and the high boiling point component (B '), a part of the low boiling point product (D) and the bottom of the main tower 123 through the NRU and the condenser 143 of the main tower 123, respectively. Through the stage (NSL) and the reboiler 153 serves to produce a high boiling point product (B), intermediate boiling point product (S).

Fourth, the third space ③ is again distilled by the low boiling point component D 'and the high boiling point component B' respectively introduced through the upper and lower portions of the second dividing wall 171 of the second space ②. After separating into the low boiling point component (D ') and the high boiling point component (B'), a part of the low boiling point product (D) and the main tower 121 through the top end (NRU) and the condenser 141 of the main column 121, respectively. Through the lower end (NSL) and the reboiler 151 to produce a high boiling point product (B), and serves to separate the middle boiling point product (S) of the remaining components through the middle end (NR).

Fifth, the aftertreatment tower 132 has a middle boiling point mixture component (S ') is supplied to the upper portion of the aftertreatment tower 132 at the upper aftertreatment tower connection end of the main tower 122 and a low boiling point at the top of the aftertreatment tower (132) processing tower 132, there is no need to provide the cooling after the vapor phase because the flow rate (V _S) of the components are refluxed to the upper end of the pylon connected to the post-processing tower 122. In addition, the liquid flow rate L _S of the high boiling point component is supplied from the lower part of the aftertreatment tower 132 to the lower aftertreatment tower connection stage of the main tower 122, and the intermediate boiling point mixture is connected to the lower aftertreatment tower connection stage of the main tower 122. Since component S ″ is refluxed to the lower portion of the aftertreatment tower 132, it is not necessary to install a reboiler in the aftertreatment tower 132.

The present invention proposes a fractional distillation method using a thermally coupled distillation column system having a dividing wall as an energy efficient distillation system. The design of the thermal combined column system with the dividing wall is based on the design of the existing thermal combined column and based on the smallest tower design. The efficiency of the distillation column is maximum when the liquid composition distribution of the column distillation stage is similar to the equilibrium distillation curve, so the first stage distillation system is designed assuming that the distillation column is operated by conversion flow operation. That is, assuming that the liquid composition in the raw material supply stage and the composition of the raw materials are the same, the first space that serves as a pretreatment tower or pretreatment tower is designed, and the second space serving as the main tower is cascaded starting from the concentration of the intermediate boiling point product. Calculate the liquid composition in the tower from the middle of the tower to the top by the balance design method, and then step down the bottom of the second space that acts as the main tower, starting with the concentration of the intermediate boiling point product. The liquid composition was sequentially calculated. By counting the number of stages having the composition of the raw material supply stage and the product from the distribution of the liquid composition thus obtained, the number of stages of the first space serving as the pretreatment tower or the pretreatment tower and the second space serving as the main tower can be determined. Since the number of stages of the tower obtained here is the ideal minimum stage structure, the number of stages in the actual tower was twice the minimum stage according to the general design standard. In addition, the reflux flow rate and the steam flow rate, which are the operating variables of the distillation system, were calculated to obtain the required product composition through the program simulation. In the monotonic distribution of the main column of the conventional thermal complex distillation system thus obtained, the concentration density zone before and after the intermediate boiling point product production stage is separated into a third space serving as a post-treatment tower or a post-treatment tower, and thus the second space and the after-treatment tower Alternatively, the number of stages of the third space serving as the aftertreatment tower was determined.

For example, when the BTX mixture is distilled by the distillation method according to the present invention, xylene (o-xylene bp 144 ° C, m-xylene bp 139.3 ° C, p-xylene bp 138 ° C) as a high boiling point component and toluene as a middle boiling point component (bp 110.8 ° C.) and benzene (bp 80.1 ° C.), which are low boiling point components, are separated.

The actual process used in the present invention is a BTX fractional distillation process for fractional distillation of a mixture of benzene, toluene and xylene obtained in the naphtha cracking process, and the flow rates of the raw materials and products of this process are shown in [Table 1].

[Table 1] Flow rate of raw materials and products of 3 towers in BTX process

(Unit: kmol / h)

Furtherance Raw material Conventional heat complex distillation column Thermocomposite Distillation Column with Split Wall Low boiling point High boiling point Mid boiling point Low boiling point High boiling point Mid boiling point    (Low boiling point) benzene 87.850 86.835 0.0000 1.0145 86.472 0.0000 1.7015 dimethyl c-pentane 0.0124 0.0113 0.0000 0.0011 0.0116 0.0000 0.0008    (Intermediate) methyl c-hexane 0.0075 0.0002 0.0000 0.0073 0.0000 0.0000 0.0064 toluene 338.10 0.0028 2.4983 335.60 0.0002 2.2289 335.62 n-octane 0.0490 0.0000 0.0035 0.0455 0.0000 0.0016 0.0474    (High boiling point) ethyl benzene 14.975 0.0000 14.747 0.2280 0.0000 14.782 0.0971 p-xylene 57.798 0.0000 57.593 0.2051 0.0000 57.443 0.1046 m-xylene 128.55 0.0000 128.14 0.4066 0.0000 127.81 0.2043 o-xylene 60.160 0.0000 60.107 0.0525 0.0000 60.004 0.0149 n-nonane 0.0057 0.0000 0.0057 0.0000 0.0000 0.0057 0.0000 n-pentyl benzene 0.3300 0.0000 0.3300 0.0000 0.0000 0.3297 0.0000 methyl-ethyl benzene 26.010 0.0000 26.010 0.0000 0.0000 25.991 0.0000 tri-methyl benzene 75.950 0.0000 75.950 0.0000 0.0000 75.919 0.0000 methyl-n-propyl bz 0.5700 0.0000 0.5700 0.0000 0.0000 0.5698 0.0000 di-ethyl benzene 0.3300 0.0000 0.3300 0.0000 0.0000 0.3299 0.0000 o-cymen 4.1200 0.0000 4.1200 0.0000 0.0000 4.1183 0.0000 tetra-methyl benzene 4.7500 0.0000 4.7500 0.0000 0.0000 4.7491 0.0000 penta-methyl benzene 2.2389 0.0000 2.2389 0.0000 0.0000 2.2388 0.0000 Sum 801.81 86.850 377.40 337.56 86.484 376.52 337.80

Table 2 shows the design results of a thermally coupled distillation column system with a dividing wall for fractional distillation of BTX mixtures.

[Table 2] Design Results of the Thermal Hybrid Distillation Column System with Split Wall and Conventional Thermal Hybrid in the Fractional Distillation Process of BTX Mixtures

Item Thermal combined distillation column system with partition wall Conventional heat complex distillation column First distillation tower ¹⁾ Second Distillation Tower ²⁾ Third distillation tower ³⁾ Pretreatment tower Pylon      (Structural design) singular 22 54 35 21 89 Raw material stage / intermediate product stage 15 20 7 28 Pretreatment tower connection 16, 39 16, 84 Aftertreatment tower connection 26, 30      (Driving design) Raw material flow rate (kmol / h) 801.8 801.8 Upper product flow rate (kmol / h) 86.48 86.85 Lower product flow rate (kmol / h) 376.5 377.4 Medium product flow rate (kmol / h) 337.8 337.8 Reflux Flow Rate (kmol / h) 340.0 1236 529.8 290.1 1792 Steam flow rate (kmol / h) 529.2 1169 340.1 492.9 1634 Energy consumption (GJ / h) 42.44 59.35

* (Number of stages is calculated from the top)

Note 1) The first distillation column corresponds to the first space of the pretreatment column or main column.

   2) The second distillation column corresponds to the first space or the second space of the main column.

   3) The third distillation column corresponds to the third space or aftertreatment column of the main column.

As shown in Table 2, the thermally coupled distillation column system with the dividing wall has a 29% higher energy efficiency than the conventional thermally coupled distillation column, and the liquid composition distribution of FIGS. 7 and 8 is balanced. It showed a similar shape to the distillation curve, showing that the tower efficiency is better than the existing system.

7 is a graph showing the distribution of the liquid composition of the distillation column using the actual stage, in which the symbol + represents the composition of the pretreatment tower 113 or the first space ① of the main column, and the symbol o represents the second space functioning as the main column. (2), symbol x represents the composition of the third space (3) functioning as a post-treatment tower or a post-treatment tower, and FIG. 8 is a post-treatment at the top of the graph showing the liquid composition distribution of the distillation column of FIG. It is the graph which extended the 3rd space (3) part of the tower 132 or the main tower.

Therefore, the combined heat distillation column system with the dividing wall has the same number of towers as the existing heat combined distillation column system but has the function of adding one more distillation column, and it is easy to change the efficiency of the distillation column system by controlling the flow connection. Have

Therefore, the fractional distillation apparatus using the thermally coupled distillation column system having the dividing wall of the present invention can constitute a new process by the design method proposed in the present invention. In particular, the distillation apparatus of the present invention is different from the conventional thermally complex distillation system. As one or two distillation towers have the same function as three distillation towers, energy efficiency can be reduced and the number of distillation towers can be reduced. to be.

Claims (6)

A condenser 141 is provided on the upper part and a reboiler 151 is provided on the lower part, and the first and second spaces 1 and 2 are formed by two first and second partition walls 161 and 171 therein. ②) and the third column ③ is composed of the main column 121 is formed, The low boiling point component (D ') and the high boiling point component (B') separated from the mixture raw material (F) in which the three components are mixed and introduced into the intermediate stage (NR) of the first space (①) of the main tower (121) are topmost. The low boiling point product (D) at the end (NRU), the high boiling point product (B) at the lowermost end (NSL), and the middle boiling point mixture component (S ') pass through the middle end (NR) of the third space (③) Each produced in (S), The length of the first dividing wall 161 and the second dividing wall 171 installed in the main tower 121 is calculated by the distillation curve of the first, second, and third spaces (①, ②, ③). Fractional distillation apparatus using a thermally coupled distillation column system having a partition wall, characterized in that the length is determined according to. The condenser 142 is provided in the upper portion and the reboiler 152 is provided in the lower portion, and the main tower 122 having the first space ① and the second space ② formed by the first dividing wall 162 therein. ) And the post-treatment tower 132 for purifying the intermediate boiling point mixture components (S ', S ") introduced from the main column 122, The low boiling point component (D '), the high boiling point component (B'), and the third mixture of the three components mixed into the intermediate stage (NR) of the first space (①) of the main column 122 are introduced and separated. The low boiling point component (D ') and the high boiling point component (B') partially introduced into the second space (②) from the first space (①) are redeposited and the low boiling point product (D) at the top end (NRU) of the main column 122. , Intermediate boiling point mixture components S 'and S "which are respectively produced as the high boiling point product B at the lowermost end NSL of the main column 122 and introduced into the aftertreatment tower 132 in the second space ②. ) Is purified and a part is produced in the middle boiling point product (S) at the intermediate stage (NRR) of the after-treatment tower 132, the remaining liquid flow rate (L _S ) and gas phase flow rate (V _S ) of the main tower 122 Is refluxed) The length of the first dividing wall 162 installed in the main column 122 is determined according to the number of stages calculated by the distillation curves of the first and second spaces ① and ②. Fractional distillation apparatus using a thermal complex distillation column system with a partition wall. The condenser 142 is provided at the upper part and the reboiler 152 is installed at the lower part, and the main tower 122 having the first space ① and the second space ② formed by the first dividing wall 162 therein. ) And the post-treatment tower 132 for purifying the intermediate boiling point mixture components (S ', S ") introduced from the main column 122, The low boiling point component (D '), the high boiling point component (B'), and the third mixture of the three components mixed into the intermediate stage (NR) of the first space (①) of the main column 122 are introduced and separated. The low boiling point component (D ') and the high boiling point component (B') partially introduced into the second space (②) from the first space (①) are redeposited and the low boiling point product (D) at the top end (NRU) of the main column 122. , The high boiling point product (B) at the bottom end (NSL) of the main tower 122, the middle boiling point product (S) is produced at the middle end (NR) of the main tower 122, and flowed in from the second space (②) After the intermediate boiling point mixture component (S ', S ") is purified, the total liquid phase flow rate (L _S ) and gas phase flow rate (V _S ) is refluxed to the main column 122, The length of the first dividing wall 162 installed in the main column 122 is determined according to the number of stages calculated by the distillation curves of the first and second spaces ① and ②. Fractional distillation apparatus using a thermal complex distillation column system with a partition wall. A pretreatment tower 113 into which the mixture raw material F in which the three components are mixed is introduced; A condenser 143 is provided on the upper part and a reboiler 153 is provided on the lower part, and the main tower 123 in which the first space ① and the second space ② are formed by the first dividing wall 163 therein. ), The low boiling point component (d) and the high boiling point component (b), in which the mixture raw material (F) mixed with the three components are introduced and separated into the intermediate stage (NRF) of the pretreatment tower (113), are formed in the first space ( ①) and the second boiling point (②) and then distilled again so that the low boiling point component (D ') is the low boiling point product (D) and the high boiling point component (B') at the top end (NRU) of the main tower (123). At the lowest end (NSL) of 123), the high boiling point product (B) and the intermediate boiling point mixture component are produced at the middle boiling point product (S) at the middle end (NR) of the second space (②), The length of the first dividing wall 163 installed in the main column 123 is determined in accordance with the stage calculated by the distillation curve of the first and second spaces ① and ②. Fractional distillation apparatus using a thermal complex distillation column system with a partition wall. The method according to any one of claims 1 to 4, The low boiling point component (B ') passes through the top end (NRU) of the main column (121, 122, 123) and the condenser (141, 142, 143), and part of the low-boiling product (D) is produced, the rest of the liquid flow rate ( L _D ) back to the top of the main column (121, 122, 123), the high boiling point component (D ') is the bottom end (NSL) and reboiler (151, 152, 153) of the main column (121, 122, 123) After being subjected to), part is produced as a high boiling point product (B), and the rest is refluxed to the lower part of the main tower (121, 122, 123) to the gas phase flow rate (V _B ) heat Fractional distillation apparatus using complex distillation column system. delete

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