RU2785341C2 - Column network with separating wall in complex technological installations - Google Patents

Abstract

FIELD: oil refining.

SUBSTANCE: invention relates to a technological installation for hydraulic purification and isomerization of naphtha and includes an installation for naphtha hydraulic purification, containing the first column with a separating wall. The first column with the separating wall includes a wall separating an upper part of the first column with the separating wall, an output connected to the second upper section of the first column with the separating wall for extraction of liquefied petroleum gas, and an output connected to a lower part of the first column with the separating wall and connected to a naphtha separator system. The invention also includes a deisopentanizer column connected to an output from a naphtha separator of the naphtha separator system, an isomerization installation connected to an output from the deisopentanizer column, and the second column with a separating wall. The second column with the separating wall includes a wall separating an upper part of the second column with the separating wall, an input connected to an output of a stabilization column of the isomerization installation, an output for extraction of the first isomerized product flow, and an output connected to a lower part of the second column with the separating wall for extraction of the second isomerized product flow. The technological installation also includes an isomerization reactor included between the deisopentanizer column and the stabilization column. The invention also concerns a method for heat integration.

EFFECT: reduction in capital and energy costs of complex oil refining processes.

20 cl, 9 dwg, 2 tbl

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This patent application claims priority and incorporates by reference the full description of U.S. Provisional Application No. 62/664,762, filed April 30, 2018.

BACKGROUND OF THE INVENTION

[0002] This section provides information about the prior art, contributing to a better understanding of various aspects of the invention. It should be understood that the statements in this section of this document are to be understood in this sense and not as an admission of prior art.

[0003] Most applications of dividing wall columns (DWC) in the oil refining industry involve stand-alone columns, whether it be an advanced column or a baseline column. Functional DWCs are commonly found in naphtha separators and reformate separators.

SUMMARY OF THE INVENTION

[0004] An exemplary process unit includes a naphtha hydrotreater comprising a first dividing wall column. The first dividing wall column includes: a wall dividing the top of the first dividing wall column into a first top section and a second top section; an outlet connected to the second top section of the first dividing wall column for recovering liquefied petroleum gas; an outlet connected to the bottom of the first dividing wall column and connected to the naphtha separator system. The exemplary process unit also includes a deisopentanizer column connected to the outlet of the naphtha separator, an isomerization unit connected to the outlet of the deisopentanizer column and including a second column with a dividing wall. The second dividing wall column includes: a wall separating the top of the second dividing wall column into a first top section and a second top section; an inlet connected to the outlet of the stabilization column of the isomerization unit; an outlet connected to the second top section of the second dividing wall column for recovering the first isomerate stream; and an outlet connected to the bottom of the second dividing wall column for recovering the second isomerate stream. The exemplary process also includes an isomerization reactor interposed between the deisopentanizer column and the stabilization column.

[0005] In some embodiments, the naphtha separator system includes a third column with a dividing wall. The third dividing wall column includes: a wall separating a middle portion of the third dividing wall column into a first middle section and a second middle section; an inlet connected to the bottom of the first dividing wall column; an outlet connected to the top of the third dividing wall column for recovering the first naphtha stream; an outlet associated with the second middle section for recovering a second naphtha stream; and an outlet connected to the bottom of the third dividing wall column for recovering the third naphtha stream.

[0006] In some embodiments, the implementation of the stabilization column is connected to the first column with a dividing wall.

[0007] In some embodiments, the isomerization reactor is connected to the bottom of the second column with a dividing wall.

[0008] In some embodiments, the second separation wall column is thermally integrated with the deisopentanizer column.

[0009] In some embodiments, the process unit includes an inlet associated with a first upper section of the first dividing wall column and connected to the bottom of the first dividing wall column.

[00010] In some embodiments, the process unit includes an outlet associated with a first top section of a second dividing wall column and connected to a deisopentanizer column.

[00011] In some embodiments, the first top section of the first partition wall column is configured to operate as a stabilizer, and the second top section of the first partition wall column is configured to operate as a deethanizer.

[00012] In some embodiments, the first top section of the second partition wall column is configured to operate as a depentanizer and the second upper section of the second partition wall column is configured to operate as a deisohexanizer.

[00013] An exemplary heat integration process for a system including a naphtha hydrotreater and an isomerization unit comprises feeding to a first dividing wall column. The first dividing wall column includes: a wall dividing the top of the first dividing wall column into a first top section and a second top section, an outlet connected to a second top section of the first dividing wall column for recovering liquefied petroleum gas; an outlet connected to the bottom of the first dividing wall column and connected to the naphtha separator system. An exemplary method includes removing liquefied petroleum gas from the second upper section of the first dividing wall column and feeding the bottom product from the first dividing wall column to the second dividing wall column. The second dividing wall column includes: a wall separating a middle portion of the second dividing wall column into a first middle section and a second middle section; an inlet connected to the bottom of the first dividing wall column; an outlet connected to the top of the second dividing wall column for recovering the first naphtha stream; an outlet associated with the second middle section for recovering a second naphtha stream; and an outlet connected to the bottom of the second dividing wall column for recovering a third naphtha stream. An exemplary process includes feeding a first naphtha stream from the top of a second dividing wall column to a deisopentanizer column, feeding the bottoms fraction from the deisopentanizer column to an isomerization reactor, and feeding product from the isomerization reactor to a stabilization column, feeding isomerate from the stabilization column to a third a column with a dividing wall. The third dividing wall column includes: a wall dividing the top of the third dividing wall column into a first top section and a second top section; an inlet connected to the outlet of the stabilization column of the isomerization unit; an outlet connected to the second top section of the third dividing wall column for recovering the first isomerate stream; and an outlet connected to the bottom of the third dividing wall column for recovering the second isomerate stream. An exemplary method includes recovering the isomerate from a third dividing wall column.

[00014] In some embodiments, the method includes feeding the ISOM stream from the stabilization column to the first top section of the first dividing wall column.

[00015] In some embodiments, the method includes exchanging heat between the fluid from the second upper section of the third dividing wall column and the bottom product of the deisopentanizer column.

[00016] In some embodiments, the method includes feeding C5 from the first upper section of the third dividing wall column to the deisopentanizer column.

[00017] In some embodiments, the method includes feeding C6 from a third separation wall column to an isomerization reactor.

[00018] In some embodiments, the method includes feeding the bottom product of the first dividing wall column to a first top section of the first dividing wall column.

[00019] In some embodiments, the second separation wall column is thermally integrated with the deisopentanizer column.

[00020] In some embodiments, the first partition wall column includes an inlet associated with the first upper section of the first partition wall column and connected to the bottom of the first partition wall column.

[00021] In some embodiments, the second dividing wall column includes an outlet associated with a first upper section of the second dividing wall column and connected to the deisopentanizer column.

[00022] In some embodiments, the first top section of the first partition wall column is configured to operate as a stabilizer, and the second top section of the first partition wall column is configured to operate as a deethanizer.

[00023] In some embodiments, the first top section of the second partition wall column is configured to operate as a depentanizer and the second upper section of the second partition wall column is configured to operate as a deisohexanizer.

BRIEF DESCRIPTION OF THE DRAWINGS

[00024] The invention is best understood from the following detailed description when read using the accompanying drawings. It should be emphasized that, in accordance with common industry practice, the various elements are not drawn to scale. In fact, the dimensions of the various elements may be arbitrarily enlarged or reduced for the sake of clarity of description.

[00025] Figure 1 shows a conventional naphtha hydrotreatment and isomerization process;

[00026] FIG. 2 is a flow diagram of DWC with heat integration for NHT and ISOM units in accordance with aspects of the invention;

[00027] Figure 3A shows a conventional naphtha separator and Figure 3B shows a DWC naphtha separator in accordance with aspects of the invention;

[00028] Figure 4A shows a traditional splitter and Figure 4B shows DWCs for LPG recovery in accordance with aspects of the invention;

[00029] Figure 5 shows the overhead heat integration between a deisopentanizer and a DWC deisohexanizer in accordance with aspects of the invention; and

[00030] FIG. 6A shows conventional depentanizer and deisohexanizer columns, FIG. 6B shows a DWC depentanizer/deisohexanizer in accordance with aspects of the invention.

DETAILED DESCRIPTION

[00031] It should be understood that the following description represents many different embodiments or examples for implementing various features of various embodiments. Specific examples of components and devices are described below for ease of description. They are, of course, merely examples and are not intended to be limiting. In addition, reference numbers and/or letters may be repeated in the description in various examples. This repetition is for simplicity and clarity and does not in itself define relationships between the various contemplated embodiments and/or configurations.

[00032] DWC technology can improve the efficiency and profitability of complex oil refineries. One such area is complex processes such as naphtha hydrotreating (NHT) and isomerization (ISOM), which typically involve a network of columns. Discussed here is the introduction of DWC technology with the combination of two or more columns in the NHT and ISOM processes to improve overall profitability.

[00033] NHT and ISOM units often operate at high pressures and temperatures, resulting in costly and energy intensive operation. With the growing demand for NHT and ISOM units in the oil refining industry, DWC can revolutionize these process flowsheets. DWCs not only increase the energy efficiency of processes, but can also provide many other benefits. These advantages include lower capital investment and the need for a relatively small footprint compared to full-fledged traditional schemes.

State of the art method

[00034] In exemplary NHT plants, such as NHT plant 100 in FIG. 1, stabilizer column 102 removes non-condensable gases from feed 104 from the reactor section. The top liquid product 106 is fed from the stabilization column 102 to the deethanizer column 108 to recover the liquefied petroleum gas (LPG) product 110. Bottoms product 112 is fed from stabilizer column 102 to a two-column naphtha separator sequence including a first naphtha separator 114 and a second naphtha separator 116. A two-column naphtha splitter sequence separates light naphtha (primarily C5-C6 components) 118, medium naphtha (C7) 120, and heavy naphtha (C8 and heavier) 122. Light naphtha 118 is processed in a deisopentanizer column 124 to separate stream 126 rich in i- C5, from the top of the deisopentanizer column 124. n-C5 and heavier or bottoms fraction 128 is fed to the ISOM reactor 130.

[00035] In most process flowsheets, the stabilization column 102 operates at high pressure, which requires the use of relatively expensive medium pressure (MP) steam. In addition, due to the use of partial condensation, there are significant losses of C3-C4 in the off-gas. This results in the use of an additional deethanizer column 108 to recover the LPG product 110 from the effluent gas. The isomerization feed is obtained from bottoms product 112 in a two-column naphtha splitter sequence.

[00036] As also shown in FIG. 1, the ISOM unit 150 comprises a plurality of columns including a stabilization column 154, a depentanizer column 156, and a deisohexanizer column 158. The deisopentanizer column 124 separates the high-octane i-C5 components 126 from the feed and recycle streams. The low octane components (n-C5 and heavier cut 128) from the bottom of deisopentanizer column 124 are sent to the ISOM reactor 130 to produce high octane components, along with some light components. The product 131 from the ISOM reactor 130 is fed to a stabilization column 154. The stabilization column 154 removes the lighter hydrocarbons (C4-) 160 in the off-gas.

[00037] The stabilized isomerate 162 is fed to the depentanizer column 156 to concentrate the C5. C5 157 is recycled from depentanizer column 156 to deisopentanizer column 124. In some aspects, a portion of C5 157 is recycled to depentanizer column 156. Downstream deisohexanizer column 158 further separates light isomerate 164 (primarily i-C6) and heavy isomerate 166 (mainly the C7+ cut), along with the concentrated n-C6 cut 168. The concentrated n-C6 cut 168 is recycled to the ISOM reactor 130 to increase the octane number.

[00038] DWCs operate on the principle of eliminating inherent thermodynamic design flaws in conventional distillation columns. One of these disadvantages arises from the back mixing of the feedstock with the side cut, based on the location of the two streams. The quality of the side cut is affected by the contamination of lighter or heavier components. The use of DWC eliminates this problem and provides a higher quality side cut. Therefore, the operation of the two naphtha separators of Figure 1 is possible in a single DWC of the present invention. The series of columns in Figure 1 represents a good opportunity to introduce DWC technology to improve the efficiency of the whole process. DWC can be used to combine the operation of two or more columns while achieving the same product specifications as the conventional scheme. As a result, capital investments are reduced by 20-30%. In addition, these columns can operate at lower temperatures or have lower operating requirements. Energy savings are expected to be 20-30% when using a DWC configuration.

Dividing wall columns in NHT and ISOM installations

[00039] Compared to NHT set 100 and ISOM set 150 of Figure 1, NHT set 100 and ISOM set 150 in Figure 2 are modified to include DWC. For example: the stabilization column 102 and the deethanizer 108 of FIG. 1 are replaced by an LPG recovery column 202 with an upper dividing wall; naphtha separators 114, 116 are replaced with a DWC naphtha separator 220; and depentanizer column 156 and deisohexanizer column 158 are replaced by depentanizer/deisohexanizer DWC column 250. The top wall LPG recovery column 202 includes a wall 203 that separates the top of the top wall LPG recovery column 202 into two halves (top section 204 and top section 206) that essentially operate as independent columns. Wall 203 prevents any mixing or leakage between the two sides. As a result, various process steps can be carried out inside the LPG recovery column 202 with an upper dividing wall.

[00040] Figures 3A and 3B show a side-by-side comparison of the two naphtha separators 114, 116 of Figure 1 with the DWC naphtha separator 220 of Figure 2. The naphtha DWC separator 220 has a middle wall 222 that separates the naphtha DWC separator 220 into two middle sections 224, 226. The bottoms product 112 from the upper dividing wall LPG recovery column 202 is fed to the middle section 224 of the naphtha DWC separator 220. The light naphtha 118 is fed from the top of the naphtha DWC separator 220 to the deisopentanizer 124. The naphtha DWC separator 220 also separates the middle naphtha 120 as a side product and the heavy naphtha 122 as a bottoms product.

[00041] FIGS. 4A and 4B show a side-by-side comparison of the stabilizer 102 and deethanizer 108 of FIG. The upper dividing wall LPG recovery column 202 has an upper wall 203 that separates the upper dividing wall LPG recovery column 202 into two upper sections 204, 206. Feedstock 104 and optionally an ISOM stream 216 enter the upper section 204. 202 upper partition wall LPG extraction, the upper section 204 is used for absorption and the upper section 206 is used for distillation. In addition, the parallel separation zones that have been formed by wall 203 tend to reduce the overall height of the LPG recovery column 202 with an upper separation wall compared to an NHT plant 100 that includes separate columns (i.e., stabilizer column 102 and column- deethanizer 108). A similar number of theoretical stages (or trays) can be placed in two zones for the desired separation.

[00042] The heavy hydrocarbon stream removes C3-C4 components from off-gas 208 from absorption section 204 of LPG recovery column 202 with an upper dividing wall. These components are concentrated and removed on the distillation side 206 as the product 110 LPG. A portion 214 of the bottoms product 112 from the top wall LPG recovery column 202 may be recycled back to the absorption section 204 and used for absorption if the feed contains a suitable amount of C5. Alternatively, the lean naphtha stream can be used along with the heavier C5 stream or independently as the absorbent medium. Other refinery off-gas streams that are rich in C3-C4 components, such as ISOM stream 216, may be fed to LPG recovery tower 202 with an upper dividing wall to improve LPG recovery (see FIG. 2 and FIG. 4). As a result, other stabilizers can operate at relatively lower pressures and at lower heat inputs.

[00043] Figure 5 illustrates the concept of an overhead DWC that combines the operation of depentanizer and deisohexanizer columns such as depentanizer column 156 and deisohexanizer column 158. The first upper section 252 of the depentanizer/deisohexanizer DWC column 250 acts as a pre-fractionation column for concentration C5 components (eg C5 components from stabilizer 154). Medium boiling components (C6) and heavy boiling components (C7 and heavier) are pushed down the depentanizer/deisohexanizer DWC column 250 into a second upper section 254 which acts as the main fractionation side. The C6 isomerate is separated as overhead product 164 from the top section 254. A concentrated 168 n-C6 stream is removed as a side stream from below the bottom of the dividing wall 251 and returned to the ISOM reactor 130. The C7+ bottoms product is obtained as heavy isomerate 166 In some embodiments, the second top section 254 is thermally integrated with the deisopentanizer column 124 via conduits 260, 261. Conduits 260, 261 are connected to a heat exchanger 262 that exchanges heat between the fluid from the second top section 254 and the bottom product of the deisopentanizer column 124 2 to 6 show other heat exchangers associated with the depicted columns. In various embodiments, these heat exchangers may be used as needed to transfer heat between the fluids of the processes described herein. 6A and 6B show a side-by-side comparison of the deethanizer column 108 and deisopentanizer column 124 of Figure 1 with the depentanizer/deisohexanizer DWC column 250 of Figure 2.

[00044] For regions with high utility costs, additional energy savings may be possible through thermal integration of the top DWC (eg, see Figure 5 and Figure 6). The depentanizer/deisohexanizer DWC column 250 is operated at elevated pressure. As a result, the hot overhead vapors on the main fractionation side 254 can be used to provide heat output to the deisopentanizer column 124 in the NHT unit (see FIGS. 5 and 6). The stream is able to provide all the heat load required by the deisopentanizer column 124; otherwise, the column usually runs on low pressure steam.

[00045] In various embodiments, aspects of Figures 2-6 may be incorporated into NHT facility 100 and ISOM facility 150 to create new systems that include the DWCs of the invention described herein.

[00046] The benefits of a DWC network in NHT and ISOM installations are summarized in Tables 1 and 2 below:

Table 1: Comparison of the number of pieces of equipment, capital and operating costs

Options unit of measurement Traditional design Construction with DWC Number of columns - eight 5 energy saving % - 24% Capital expenditures % A basic level of 70% of the base level

Table 2: Comparison of heat costs

Options unit of measurement Traditional design Real DWC with heat integration Feed rate to NHT unit t/h 57 57 Isomerization product t/h 28.6 28.6 RON of the isomerization product - 92 92 LPG Product Speed t/h 5.00 7.5 Exhaust gas velocity t/h 3.7 1.2 NHT Stabilizer Gcal/h (MW) 7.0 (8.14) 7.3 (8.49) Deethanizer Gcal/h (MW) 2.0 (2.33) Naphtha separator 1 & 2 Gcal/h (MW) 16.6 (19.31) 13.3 (15.47) Deisopentanizer Gcal/h (MW) 12.7 (14.77) 0.9 (1.05) Stabilizer ISOM Gcal/h (MW) 3.0 (3.49) 3.0 (3.49) Depentanizer Gcal/h (MW) 8.0 (9.30) 20.9 (24.31) Deisohexanizer Gcal/h (MW) 10.4 (12.10) Total heat output Gcal/h (MW) 59.7 (69.43) 45.4 (52.80)

[00047] DWC is an innovative way to reduce the capital and energy costs of complex refinery processes such as naphtha isomerization and hydrotreating. Integrating DWC technology into an NHT/ISOM flowsheet can provide significant benefits, including: fewer columns and associated equipment for the entire configuration; improved LPG recovery; reduction of energy costs through the use of low-temperature systems for heating; and better thermal integration inside the columns.

The term "substantially" is defined as substantially, but not necessarily all of, what is specified (and includes what is specified; for example, substantially 90 degrees includes 90 degrees, and substantially parallel includes parallel), as understood by one of ordinary skill in the art. . In any embodiment described, the terms "substantially", "approximately", "typically" and "about" may be replaced by the words "in the range [as a percentage] of the specified", where the percentage includes 0.1, 1, 5 and 10 percent.

[00048] The foregoing describes the features of several embodiments so that those skilled in the art can better understand aspects of the invention. Those skilled in the art should understand that they can easily use the description as a basis for developing or modifying other processes and structures to accomplish similar goals and/or achieve similar benefits of the embodiments presented herein. Those skilled in the art will also appreciate that such equivalent constructs do not depart from the spirit and scope of the invention, and that they may make various changes, substitutions, and modifications without departing from the spirit and scope of the invention. The scope of the invention is to be determined only by the plain text of the following claims. The term "comprising" in the claims means "comprising at least" so that the listed list of elements in the claims is an open group. The singular terms given are intended to include plural forms unless specifically excluded.

Claims (56)

1. Process unit for hydrotreating and isomerization of naphtha, containing: a naphtha hydrotreater comprising a first dividing wall column, the first dividing wall column comprising: a wall separating the top of the first dividing wall column into a first top section and a second top section; an outlet connected to the second top section of the first dividing wall column for recovering liquefied petroleum gas; and an outlet connected to the bottom of the first dividing wall column and connected to the naphtha separator system; a deisopentanizer column connected to an outlet of a naphtha separator of the naphtha separator system; an isomerization unit connected to the outlet of the deisopentanizer column and comprising a second dividing wall column, the second dividing wall column comprising: a wall dividing the top of the second dividing wall column into a first top section and a second top section; an inlet connected to the outlet of the stabilization column of the isomerization unit; an outlet connected to the second top section of the second dividing wall column for recovering the first isomerate stream; and an outlet connected to the bottom of the second dividing wall column for recovering a second isomerate stream; an isomerization reactor connected between the deisopentanizer column and the stabilization column. 2. The process plant of claim 1, wherein the naphtha separator system comprises a third dividing wall column, wherein the third dividing wall column comprises: a wall separating the middle part of the third dividing wall column into a first middle section and a second middle section; an inlet connected to the bottom of the first dividing wall column; an outlet connected to the top of the third dividing wall column for recovering the first naphtha stream; an outlet associated with the second middle section for recovering a second naphtha stream; and an outlet connected to the bottom of the third dividing wall column to recover the third naphtha stream. 3. Process plant according to claim 1, in which the stabilization column is connected to the first column with a dividing wall. 4. Process plant according to claim 1, in which the isomerization reactor is connected to the bottom of the second column with a dividing wall. 5. Process plant according to claim 1, wherein the second dividing wall column is thermally integrated with the deisopentanizer column. 6. Process plant according to claim 1, also comprising an inlet associated with the first upper section of the first column with a dividing wall and connected to the bottom of the first column with a dividing wall. 7. Process plant according to claim 1, also containing an outlet associated with the first upper section of the second dividing wall column and connected to the deisopentanizer column. 8. The process plant of claim 1, wherein the first top section of the first dividing wall column is operable as a stabilizer and the second top section of the first dividing wall column is operable as a deethanizer. 9. The process plant of claim 1, wherein the first top section of the second partition wall column is configured to operate as a depentanizer and the second upper section of the second partition wall column is configured to operate as a deisohexanizer. 10. A thermal integration method for a system comprising a naphtha hydrotreater and an isomerization unit, the method including the steps of: feed into the first dividing wall column (202), wherein the first dividing wall column (202) comprises: a wall dividing the upper part of the first column (202) with a dividing wall into a first upper section and a second upper section; an outlet connected to the second top section of the first dividing wall column (202) for recovering liquefied petroleum gas; and an outlet connected to the bottom of the first dividing wall column (202) and connected to the naphtha separator system; remove liquefied petroleum gas from the second upper section of the first column (202) with a dividing wall; the bottom product from the first column (202) with a dividing wall is fed into the third column (220) with a dividing wall, the third column (220) with a dividing wall containing: a wall dividing the middle part of the third column (220) with a dividing wall into a first middle section and a second middle section; an inlet connected to the bottom of the first column (202) with a dividing wall; an outlet connected to the top of the third dividing wall column (220) for recovering the first naphtha stream; an outlet connected to the middle section of the third column (220) with a dividing wall for recovering the second naphtha stream; and an outlet connected to the bottom of the third dividing wall column (220) for recovering a third naphtha stream; feeding the first naphtha stream from the top of the third dividing wall column (220) to the deisopentanizer column; the bottom fraction is fed from the deisopentanizer column to the isomerization reactor; feeding the product from the isomerization reactor into a stabilization column; the isomerizate is fed from the stabilization column into the second column (250) with a dividing wall, the second column (250) with a dividing wall containing: a wall dividing the upper part of the second column (250) with a dividing wall into a first upper section and a second upper section; an inlet connected to the outlet of the stabilization column of the isomerization unit; an outlet connected to the second top section of the second dividing wall column (250) for recovering the first isomerate stream; and an outlet connected to the bottom of the second dividing wall column (250) for recovering the second isomerate stream; recovering the isomerizate from the third column (220) with a dividing wall. 11. The method of claim 10, further comprising the step of feeding the ISOM (isomerization) stream from the stabilization column to the first top section of the first dividing wall column. 12. The method of claim 10, further comprising the step of exchanging heat between the fluid from the second upper section of the third dividing wall column and the bottom product of the deisopentanizer column. 13. The process of claim 10, further comprising feeding the C5 fraction from the first upper section of the third dividing wall column to the deisopentanizer column. 14. The method of claim 10, further comprising feeding the C6 fraction from the third separation wall column to the isomerization reactor. 15. The method of claim 10, further comprising feeding the bottom product of the first dividing wall column to the first upper section of the first dividing wall column. 16. The method of claim 10, wherein the second separation wall column is thermally integrated with the deisopentanizer column. 17. The method of claim 10, wherein the first partition wall column further comprises an inlet associated with the first upper section of the first partition wall column and connected to the bottom of the first partition wall column. 18. The method of claim 10, wherein the second dividing wall column further comprises an outlet associated with a first upper section of the second dividing wall column and connected to the deisopentanizer column. 19. The method of claim 10, wherein the first top section of the first dividing wall column is operable as a stabilizer and the second top section of the first dividing wall column is operable as a deethanizer. 20. The method of claim 10, wherein the first top section of the second partition wall column is configured to operate as a depentanizer and the second upper section of the second partition wall column is configured to operate as a deisohexanizer.

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