TWI610712B - Series connected simulated moving bed system - Google Patents

Abstract

A tandem simulated moving bed system is suitable for separating intermediate components with a three-component mixture with a retention constant in the middle. The tandem simulated moving bed system includes a first-stage simulated moving bed, a second-stage simulated moving bed, a lateral flow pipeline, and a liquid concentration homogenization module. The first and second-stage simulated moving beds are composed of a mobile phase and a stationary phase. The mobile phase flows in the first direction in the first and second-stage simulated moving beds, respectively. The stationary phase is opposite to the mobile phase. The first direction simulates movement in the second direction. The side flow pipeline and the liquid concentration homogenization module are connected to the first-stage simulated moving bed and the second-stage simulated moving bed.

Description

Tandem Simulated Moving Bed System

This case relates to a simulated moving bed system, and in particular to a tandem simulated moving bed system capable of separating intermediate retention components.

Traditional four-segment or three-segment simulated moving bed (SMB) can only separate a multi-component mixture into two component groups. If the intermediate retention component is to be separated separately, it needs to be matched with other separation technologies or two simulated moving bed operations. The traditional four-segment simulated moving bed cannot separate the intermediate retention components, which makes the industrial application of the simulated moving bed mainly focus on simple raw material systems, such as glucose / fructose separation, xylene isomer separation, optical Isomer separation and so on. Natural raw materials or fermentation-synthesized pharmaceutical raw materials are complicated to use and have low concentrations, and often have very strong retention properties. Therefore, the use of simulated moving beds is limited.

At present, scholars have proposed a series of simulated moving beds to separate the three-component intermediate retention components, and also calculated its feasibility through simulation. However, there are still some problems with this tandem simulated moving bed design. First, concentration fluctuations in the side flow used to cascade the first and second stage simulated moving beds have a large effect on the separation effect of the second stage simulated moving beds. Second, between the first and second-stage simulated moving beds in series, an on-line concentration process must be installed, which complicates the manufacturing process. Third, when the system has super-retentive components, it will cause the system to fail to operate stably for a long time. Therefore, in addition to the system and method for separating the intermediate retentive components, a design that can timely remove the strong retentive components from the system can effectively solve the problems encountered in the application of simulated moving bed technology in these industries.

This case provides a variety of tandem simulated moving bed systems and multi-component chromatography separation methods, which can provide sidestreams with stable concentrations, continuously and stably separate intermediate retention components, and can expel strong retention components outside the system in a timely manner.

A tandem simulated moving bed system of the present case is suitable for separating a mixture. The mixture includes a first component (group), a second component (group), and a third component (group), each having a first retention constant, a Second retention constant and third retention constant. The tandem simulated moving bed system includes first and second-stage simulated moving beds, side flow pipelines, buffer tanks, side flow pressure regulators, side flow pumps, and regeneration sections. The first stage simulated moving bed includes first, second and third sections arranged along the first direction. The second-stage simulated moving bed includes fourth and fifth sections arranged along the first direction. The first and second-stage simulated moving beds are composed of a mobile phase and a stationary phase. The mobile phase flows in the first direction in the first and second-stage simulated moving beds, respectively. The stationary phase is opposite to the mobile phase. The first direction simulates movement in the second direction. The side flow pipeline is connected to the first and second stage simulated moving beds and includes a side flow inlet and a side flow outlet. The side flow inlet is connected between the first section and the second section, and the side flow outlet is connected between the fourth section and the fifth section. The buffer tank is arranged on the side flow line. The side-flow pressure regulator is disposed on the side-flow line and is located between the buffer tank and the side-flow outlet. The side flow pump is arranged on the side flow line and is located between the buffer tank and the side flow pressure regulator. The first simulated moving bed is suitable for separating the first component (group) of the mixture, and the second and third components (group) of the mixture are suitable for passing from the second section to the buffer tank, the side flow pump, and the side along the side flow pipeline. The flow pressure regulator moves between the fourth and fifth sections, and is separated in the second stage simulated moving bed. The regeneration section is a sixth section, which is arranged beside the fifth section along the first direction and includes a wetting zone and a strong cleaning zone.

In an embodiment of the present invention, the above-mentioned tandem simulated moving bed system further includes a central valve group, including a first part and a second part, wherein the first part is selectively rotated relative to the second part along an axis to switch the first part The alignment state between the plurality of first channels of the second portion and the plurality of second channels of the second portion, and some of these second channels are connected to some of the second channels respectively to the first, second, third, Fourth, fifth and sixth sections.

In an embodiment of the present application, the above-mentioned tandem simulated moving bed system further includes multiple liquid supply tanks, multiple mainstream pumps, multiple liquid recovery tanks, and multiple mainstream pressure regulators. The liquid supply tanks are respectively connected to a part of the first channels, and the mobile phase includes at least one flushing solution, and each liquid supply tank contains at least one flushing solution. The mainstream pumps are respectively connected to the liquid supply tanks and the partial first channels. The liquid recovery tanks are respectively connected to a part of the first channels and are adapted to receive at least one flushing liquid. The mainstream pressure regulators are respectively connected to the liquid recovery tanks and the local first channels.

In an embodiment of the present invention, the number of the liquid supply tanks and the mainstream pumps are five respectively, and the five liquid supply tanks and the five mainstream pumps are respectively connected to the source of the first section, the second section and Between the third section, the source of the fourth section, the wetting zone and the strong cleaning zone.

In an embodiment of the present invention, the number of the liquid recovery tanks and the mainstream pressure regulators are two respectively, and the two liquid recovery tanks and the two mainstream pressure regulators are respectively connected to the end of the third section, the first The end of five sectors.

In an embodiment of the present invention, each of the first, second, third, fourth, fifth, and sixth sections includes at least one pipe string, and each of the pipe strings is filled with fixed particles having pores inside. phase.

In an embodiment of the present invention, the mobile phase flows through the strong cleaning area of the first, second, third, fourth, fifth, and sixth sections in a first direction, and flows in a second direction. Wetting zone through the sixth section.

Based on the above, the tandem simulated moving bed system of the present case separates the intermediate components with the retention constants in the middle of the mixture through the side flow pipelines in series with the first and second stage simulated moving beds. Since the simulated moving bed will have concentration fluctuations when switching these pipe columns to different sections, the concentration fluctuations in the lateral flow of the side flow pipeline have a great impact on the separation effect of the second stage simulated moving bed. In order to reduce the The concentration fluctuates. In this case, a buffer tank is installed on the side stream pipeline. The medium and high retention components will enter the buffer tank first in the side stream pipeline. After the concentration in the buffer tank stabilizes, it will flow to the second stage simulation movement. Bed, so that the second-stage simulated moving bed has better separation effect. In addition, the tandem simulated moving bed system in this case further includes a regeneration section. The stationary phase of the first section of the first-stage simulated moving bed is cleaned and recycled back to the second-stage simulated moving bed after the regeneration section, without The retentive components are carried to the second-stage simulated moving bed, which can timely and effectively discharge the strong retentive components, so that the tandem simulated moving bed system can be used for a long time. In addition, the design of the regeneration section can also avoid the need to increase the velocity of the side stream in order to ensure the function of the second-stage simulated moving bed, which can more conveniently set the operating conditions.

In order to make the above features and advantages of this application more comprehensible, embodiments are described below in detail with the accompanying drawings as follows.

The tandem simulated moving bed system 100 of this embodiment is suitable for separating an intermediate component having a retention constant in the middle of a mixture having at least three components. More specifically, the mixture includes at least a first component (group) A, a second component (group) B, and a third component (group) C, each having a first retention constant, a second retention constant, and a first Three retention constants. Of course, the tandem simulated moving bed system 100 of this embodiment can also be applied to mixtures with more than three components (for example, having four components), and is not limited to use in separating three-component mixtures.

FIG. 1 is a schematic diagram of a tandem simulated moving bed system 100 according to an embodiment of the present application. Please refer to FIG. 1 first. The tandem simulated moving bed system 100 of this embodiment uses a six-section simulated moving bed as an example. The tandem simulated moving bed system 100 includes a first-stage simulated moving bed 110, a second-stage simulated moving bed 120, a lateral flow line 140, a liquid concentration homogenizing module 150, and a regeneration section 130.

Specifically, the first-stage simulated moving bed 110 includes first, second, and third sections Z1, Z2, and Z3 arranged in a first direction D1. The second-stage simulated moving bed 120 includes fourth and fifth sections Z4 and Z5 arranged along the first direction D1. In this embodiment, the first, second, and third sections Z1, Z2, Z3, the fourth and fifth sections Z4, and Z5 each have two pipe columns 180. The regeneration section 130 is a sixth section Z6, which is arranged next to the fifth section along the first direction D1 and also includes two pipe strings 180, one of which is a wetting zone 132, and the other pipe 180 is strong. Washing area 134. Of course, the number of pipe strings 180 in each section may also be one or more than three, which is not limited thereto.

The first and second-stage simulated moving beds 110 and 120 and the regeneration section 130 are respectively composed of a mobile phase and a stationary phase. More specifically, each column 180 in each section is filled with a stationary phase having pores inside the particles, and the mixture is adsorbed on the stationary phase after being sent into the specific column 180. The mobile phase includes at least one washing liquid L1, L2. The mobile phase flows into and out of the column 180 to rinse the mixture adsorbed on the stationary phase to separate the components. As shown in FIG. 1, the mobile phase flows in the first direction D1 in the strong cleaning zone 134 in the first and second-stage simulated moving beds 110 and 120 and the regeneration section 130, respectively. The stationary phase is opposite to the mobile phase. The second direction D2 opposite to the first direction D1 simulates movement. The mobile phase and the stationary phase are contacted with each other in countercurrent to flush and separate components with lower retention constants.

To further explain here, the way in which the stationary phase simulates movement in the second direction D2 relative to the mobile phase is to constantly switch the inlet and outlet of the mobile phase and the inlet of the mixture to create the stationary phase in the opposite direction (the reverse in Figure 1). (Hour hand) flow phenomenon. For example, in the current FIG. 1, the column 180 from left to right is the first, second, third, fourth, fifth, and sixth sections Z1, Z2, Z3, Z4, Z5, and Z6. Let the inlet and outlet of the mobile phase and the inlet of the mixture switch to the next column 180 clockwise after a period of time, as shown in Figure 2.

FIG. 2 is a schematic diagram of the serial simulated moving bed system 100 of FIG. 1 at the next timing. As shown in FIG. 2, the column 180 from left to right is the strong cleaning zone 134 of the sixth section Z6, the first, second, third, fourth, and fifth sections Z1, Z2, Z3, Wetting zone 132 of Z4, Z5 and sixth zone Z6. After a period of time, it continues to switch to the next pipe column 180 in the clockwise direction. After continuous switching, an analog state similar to that in which the stationary phase flows in the counterclockwise direction is formed. At the same time, the mobile phase continues to flow clockwise continuously to simulate the process of continuous reverse flow contact between the stationary phase and the mobile term.

Therefore, when two components with different retention constants enter the simulated moving bed and are adsorbed on the stationary phase and washed away by the mobile phase, the components with low retention constants will be washed out of the stationary phase by the mobile phase and go with the mobile phase. Move clockwise to the next column 180 in the first direction D1; because the component with high retention constant is not easily washed out by the mobile phase, after the import and export switch, it will move to the first counterclockwise direction as if driven by the stationary phase. The next column 180 in two directions D2.

Please return to FIG. 1, the side stream line 140 is connected to the first and second stage simulated moving beds 110 and 120 so that the first and second stage simulated moving beds 110 and 120 are connected in series. The lateral flow line 140 includes a lateral inlet 142 and a lateral outlet 144. The side flow inlet 142 is connected between the first section Z1 and the second section Z2 of the first-stage simulated moving bed 110, and the side flow outlet 144 is connected between the fourth section and the fifth section of the second-stage simulated moving bed 120. Between paragraphs.

It is worth mentioning that because part of the mixture will move from the side stream line 140 to the second-stage simulated moving bed 120, the concentration fluctuation of the mixture in the side stream line 140 has a large effect on the separation effect of the second-stage simulated moving bed 120. In order to reduce the concentration fluctuation of the mixture in the side flow line 140, the present embodiment is configured by disposing the liquid concentration uniformization module 150 on the side flow line 140. More specifically, the liquid concentration homogenizing module 150 includes a buffer tank 152, and the mixture in the side flow line 140 first enters the buffer tank 152, and then flows to the second stage after the concentration in the buffer tank 152 stabilizes. The moving bed 120 is simulated so that the second-stage moving bed 120 has a better separation effect. In an embodiment not shown, the liquid concentration uniformization module 150 further includes an agitator located in the buffer tank 152 to accelerate the uniformity of the liquid concentration flowing into the buffer tank 152.

The side-flow pressure regulator 155 is disposed on the side-flow line 140 and is located between the buffer tank 152 and the side-flow outlet 144. The side flow pump 157 is disposed on the side flow line 140 and is located between the buffer tank 152 and the side flow pressure regulator 155. In this embodiment, in addition to increasing the pressure of the side flow in the side flow line 140, the side flow pump 157 also has a metering function. In addition, in this embodiment, the side-flow pressure regulator 155 is, for example, a back pressure valve, which provides a pressure-stabilizing effect. The pressure of the side-flow in the side-flow line 140 needs to be within a certain range to pass from the side-flow line 140. Flow to the second stage simulated moving bed 120. That is, the side-flow pressure regulator 155 can control the flow velocity of the fluid flowing into the second-stage simulated moving bed 120 within a certain range. In this embodiment, part of the mixture from the first-stage simulated moving bed 110 to the side-flow pipeline 140 passes through the buffer tank 152, the side-flow pump 157, and the side-flow pressure regulator 155 in order, and then enters the second-stage simulation. The moving bed 120 can provide a mixture of stable concentration and flow rate to the second-stage simulated moving bed 120.

According to the above operation mode, FIG. 3 is a schematic flowchart of a multi-component chromatography separation method of a tandem simulated moving bed system 100 according to an embodiment of the present invention. Referring to FIG. 3, the tandem simulated moving bed system 100 of this embodiment can separate the second component (group) B with a retention constant in the middle through the following multi-component chromatography separation method. The component chromatography separation method 200 includes the following steps.

First, in step 210, a tandem simulated moving bed system 100 is provided. The tandem simulated moving bed system 100 includes a first-stage simulated moving bed 110, a second-stage simulated moving bed 120, a lateral flow line 140, and a liquid concentration homogenization module 150. The first and second-stage simulated mobile beds 110 and 120 are respectively composed of a mobile phase and a stationary phase. The mobile phase includes at least one flushing liquid L1 and L2. The stationary phase particles have pores therein. The second-stage simulated moving beds 110 and 120 flow toward the first direction D1, and the stationary phase simulates movement with respect to the mobile phase in the second direction D2 opposite to the first direction D1. The first-stage simulated moving bed 110 includes moving along the first direction The first, second, and third sections Z1, Z2, and Z3 arranged in one direction D1. The second-stage simulated moving bed 120 includes fourth and fifth sections Z4 and Z5 arranged in the first direction D1. 140 is connected between the first section Z1 and the second section Z2 and between the fourth section and the fifth section, and the liquid concentration uniformization module 150 is disposed on the side flow line 140.

In the present embodiment, the washing liquid L1 of the mobile phase of the first-stage simulated moving bed 110 is fed in from the source of the first section Z1 and moves in the first-stage simulated moving bed 110 along the first direction D1.

Next, in step 220, the mixture is injected between the second and third sections Z2 and Z3, where the mixture includes a first component (group) A, a second component (group) B, and a third component (group) C, respectively. It has a first retention constant, a second retention constant, and a third retention constant from small to large. More specifically, the mixture is fed into the first-stage simulated moving bed 110 from between the second section Z2 and the third section Z3 of the first-stage simulated moving bed 110.

Further, in step 230, the second and third relative flow rates m2 and m3 of the second and third sections Z3 are controlled to be between the first retention constant and the second retention constant, so that the first component (group) A Move to the third section Z3, the second component (group) B and the third component (group) C move to the second section Z2 and move to the second stage along the side stream line 140 and the liquid concentration uniformization module 150 Simulation of moving bed 120.

In detail, because the first component (group) A has the lowest retention constant, the first component (group) A flows out as the mobile phase flows to the third section Z3, and the first component (group) A is separated from The second and third components (groups) B and C. The second and third components (groups) B and C with higher retention constants will move to the second section Z2, and some of the second and third components (groups) B and C will flow along the side stream line 140 to The second stage simulates between the fourth and fifth sections Z4 and Z5 of the moving bed 120.

Next, in step 240, the fourth and fifth relative flow rates m4 and m5 of the fourth and fifth sections Z4 and Z5 are controlled to be between the second retention constant and the third retention constant, so that the third component (group) C moves to the fourth section Z4, the second component (group) B moves to the fifth section Z5, and the second component (group) B is separated.

The washing liquid L2 of the mobile phase 2 of the second-stage simulated moving bed 120 is fed in from the source of the fourth section Z4 and moves in the first direction D1 in the second-stage simulated moving bed 120. Similarly, since the retention constant of the second component (group) B is lower than the retention constant of the third component (group) C, the second component (group) B will flow out as the mobile phase flows to the fifth zone Z5, The second component (group) B is separated from the third component (group) C. In this way, the second component (group) B with the retention constant in the middle can be successfully separated. It should be noted that, since the mobile phases of the first and second-stage simulated moving beds 110 and 120 operate independently, the washing liquids L1 and L2 of the first and second-stage simulated moving beds 110 and 120 may be the same or different.

It is also worth mentioning that in the first-stage simulated moving bed 110 of FIG. 1, the third component (group) C with a high retention constant will simulate the movement to the second direction D2 and stay in the first section Z1. In phase (that is, the string 180 located at the far left of FIG. 1). In order to prevent the third component (group) C with high retention constant from contaminating the column 180 and preventing the serial simulated moving bed system 100 from continuously acting for a long time, in this embodiment, the sixth phase of the strong cleaning zone 134 is controlled. The flow velocity m6 is greater than the third retention constant, and the third component (group) C (even the fourth component with a higher retention constant, etc.) C with a high retention constant is removed through the regeneration section 130 to regenerate the stationary phase. Please refer to Figure 2. After the next switch, the leftmost column 180 in Figure 1 is converted into the strong cleaning zone 134 in the regeneration section 130 (sixth section Z6), which was originally adsorbed in the high retention constant of the stationary phase. The third component (group) C can leave the stationary phase through the action of reverse strong cleaning. Therefore, the design of the tandem simulated moving bed system 100 in this embodiment through the regeneration section 130 can ensure that after each switching, the stationary phase to which the third component (group) C of the high retention constant is originally attached can be completely regenerated. That is to say, if the mixture also has a fourth component (group) (group not shown) with stronger retention, the sixth section can effectively remove the fourth component (group) which has higher retention than the third component (group) C ) To ensure the complete regeneration of the stationary phase and thus the stability of long-term operation.

Thereafter, the stationary phase originally in the strong cleaning zone 134 will be converted into a wetting zone 132 after the next switching (not shown). In the wetting zone 132, the moving direction of the mobile phase is the same as the simulated moving direction of the stationary phase. (Moving in the second direction D2), mainly for wetting the stationary phase. In the next switch, the stationary phase originally in the wetting zone 132 is converted to the fifth section Z5 of the second-stage simulated moving bed 120, which can effectively avoid bringing any third component (group) C with strong retention into the first section. The five sections Z5 pollute the second component (group) B of the intermediate retention property.

In addition, the mechanism components that control the flow of the mobile phase and the mixture between each time zone (for example, in the situation of FIG. 1) will be described below. FIG. 4 is a schematic diagram of the piping of FIG. 1. Referring to FIG. 1 and FIG. 4 at the same time, the tandem simulated moving bed system 100 further includes a plurality of liquid supply tanks 170, a plurality of mainstream pumps 172, a plurality of liquid recovery tanks 174, and a plurality of mainstream pressure regulators 176. The liquid supply tank 170 mainly stores mobile phases or mixtures. These mainstream pumps 172 are connected to these liquid supply tanks 170, respectively, and provide sufficient pressure for the mobile phase or mixture to enter the first and second-stage simulated moving beds 110, 120, and Regeneration section 130. The liquid recovery tank 174 stores the recovered mobile phase or mixture. The mainstream pressure regulators 176 are respectively connected to the liquid recovery tanks 174 to reduce the pressure so that the mobile phase or the mixture can move to the liquid recovery tank 174.

More specifically, in this embodiment, the number of the liquid supply tanks 170 and the mainstream pumps 172 are five, and the five liquid supply tanks 170 and the five mainstream pumps 172 are connected to the first through the first channel 164, respectively. The source of the zone Z1, between the second zone Z2 and the third zone Z3, the source of the fourth zone Z4, the wetting zone 132 and the strong cleaning zone 134. The number of the liquid recovery tanks 174 and the mainstream pressure regulators 176 are two, and the two liquid recovery tanks 174 and the two mainstream pressure regulators 176 are connected to the end of the third section Z3, the first through the first channel 164, respectively. The end of the five sector Z5.

In addition, briefly introduce how the import and export of mobile phase and import of mixture are switched. 5 is a schematic cross-sectional view of a central valve group of the tandem simulated moving bed system of FIG. 1. Please refer to FIG. 4 and FIG. 5 at the same time. The tandem simulated moving bed system 100 further includes a central valve group 160, and the central valve group 160 includes a first part 162 and a second part 166. 166 is the lower half of the valve group. The first section 162 includes a plurality of first channels 164 (24 in this embodiment is taken as an example), and the second section 166 includes a plurality of second channels 168 (24 in this embodiment is taken as an example). It should be noted that FIG. 4 only schematically shows the first channel 164 of the first portion 162 and the second channel 168 of the second portion 166 in a row. Actually, the first channel 164 and the second channel Please refer to FIG. 6 and FIG. 7 for the arrangement of 168.

Fig. 6 is a schematic cross-sectional view taken along the line A-A of Fig. 5. Fig. 7 is a schematic cross-sectional view taken along the line B-B in Fig. 5. It should be noted that although FIG. 6 and FIG. 7 are only for the channel section of the first section 162, the channel section of the second section 166 will be similar to that of FIG. 6 and FIG. 7, so the channel section of the second section 166 will not be shown. .

As can be seen from FIG. 6, in this embodiment, the first portion 162 of the central valve group 160 is cylindrical, and the first channels 164 are arranged at an equal angle on the cylinder. From FIG. 6, it can be known that the first channels 164 will be arranged into Ring. The central valve group 160 of this embodiment is an example of a valve group applicable to 24 pipe strings 180. In the cross-sections of FIGS. 6 and 7, there are 24 first channels 164, that is, each has 24 first channels. Channel 164. In this embodiment, since there are 12 tubing columns 180 in total, the operator can select a plurality of equal-angle or non-equal-angle first channels 164 among the 24 first channels 164 to communicate with the liquid supply tank 170 and the liquid recovery. The groove 174, similarly, the operator can select 12 of the 24 second channels 168 to be connected to the 12 pipe strings 180 with the same or non-equal angle second channels 168. It can be seen in the sections of FIG. 6 and FIG. 7 that the extension angles of the first channels 164 on different planes (A-A section, B-B section) are different to avoid each other.

As shown in FIG. 4, twelve first channels 164 of the first portion 162 are respectively connected to the liquid supply tanks 170 and the liquid recovery tanks 174, that is, the inlet and outlet of the mobile phase and the inlet of the mixture. Twelve of these second channels 168 of the second section 166 are connected to the twelve columns 180 of the first, second, third, fourth, fifth, and sixth sections Z6, that is, the first, Two-stage simulated moving beds 110 and 120 and a regeneration section 130.

In this embodiment, the first portion 162 of the central valve group 160 is non-rotating, and the second portion 166 is selectively rotatable relative to the first portion 162 along an axis. Through the second portion 166 rotating at a specific angle with respect to the first portion 162 at different timings, the alignment state between the plurality of first channels 164 of the first portion 162 and the plurality of second channels 168 of the second portion 166 is switched to achieve The aforementioned analog state in which the stationary phase flows counterclockwise.

In addition, since the first and second-stage simulated moving beds 110 and 120 are connected in series, the second and third relative flow velocity m2 and m3 of the second and third sections Z3 will affect the fourth and fifth sections of the fourth and fifth sections. Five relative velocity m4 and m5. The following will briefly discuss the relationship between the flow rates of these sections in the first and second-stage simulated moving beds 110 and 120 to improve the purity, recovery rate of the second component (group) B, and increase the efficiency of the stationary phase. 8 to 11 are the second and third relative flow velocity m2 and m3 of the second and third sections Z3 of the tandem simulated moving bed system 100 of FIG. 1 and the fourth and fifth relative flows of the fourth and fifth sections, respectively. Relationship between flow velocity m4 and m5.

(1) 其中Ki為i成分的亨利常數，而F為層析管柱180的固液相體積比。 First, under low concentration conditions, the adsorption isotherm curve of the solute component in the stationary phase is linear, and its slope is the Henry constant, and its linear velocity in the column 180, ui, and the j-th The relationship between the linear velocity, vj, of the mobile phase can be explained using the following formula:

(1) where Ki is the Henry constant of component i, and F is the solid-liquid volume ratio of chromatography column 180.

(2) 其中Qj為j區的流動相體積流速，tsw為閥門的切換時間，VC為層析柱的空管體積，ε為填料床層空隙率。 According to this formula, the direction of each component's movement in each section can be adjusted by setting the relative volume flow rates of the mobile phase and the stationary phase in different sections, where the relative volume flow rate is defined as follows:

(2) where Qj is the volumetric flow rate of the mobile phase in zone j, tSW is the valve switching time, VC is the empty tube volume of the chromatography column, and ε is the porosity of the packed bed.

(3a)

(3b)

(3c) 另依據質量守恆：

(4) 所以，質量守恆可以改寫成：

(5) For a three-component mixture of retention behavior, when using the tandem simulated moving bed system 100 of FIG. 1 for separation, the operating conditions should meet the limiting conditions defined by the triangle theory:

(3a)

(3b)

(3c) Also based on conservation of mass:

(4) Therefore, the conservation of mass can be rewritten as:

(5)

In terms of the relative flow rates of the second zone Z2 m2 of the second horizontal axis, the third segment of the third relative flow rates of ₃ m Z3 ordinate, the operating conditions can be completely separated just located inside the triangle, that is to say The separable operating range is the triangle in this coordinate graph. The vertices of the triangle have the best separation effect and separation efficiency.

According to this, the steps for setting the operating conditions of the tandem simulated moving bed system 100 of Fig. 1 are shown in Fig. 8: (a) Set m2 and m3 so that the coordinates of point a (m2, m3) satisfy the formula (3b); (b) Set m1 so that the coordinates of point b (m2, m1) satisfy the formula (3a); (c) Set m4 so that the coordinates of point c (m4, m5) satisfy the formula (3c). According to the mass conservation of formula (5), the line connecting point b and point c must be parallel to the diagonal of FIG. 8. When a single operating condition is changed, the coordinates on the (m2, m3) phase plane will be changed at the same time in the steps a-b-c of setting the operating conditions. When (m2, m3) representing the operating conditions of the first-stage simulated moving bed 110 is fixed, changes in the following operating conditions will cause displacement of (m4, m5) representing the operating conditions of the second-stage simulated moving bed 120: (1) increase m1 (point b moves up to b '), it means that the feed of the second-stage simulated moving bed 120 will increase, so m5 will also increase, so point c moves vertically upward, as shown in FIG. 9. (2) Increase m4 (point c is shifted to the right), because m5 will also increase, so point c moves to the right along line bc, as shown in Figure 10. (3) After the flow rate is fixed, if you increase the switching time, set the a-b-c step of the operating conditions, and the coordinates on the (m4, m5) phase plane are shifted to the right, as shown in Figure 11.

Using the above three characteristics, the following steps can be used to establish optimized operating conditions: First, under a fixed difference between m4 and m2, change the valve switching time tsw so that (m2, m3) and (m4, m5) are two points , The coordinates move diagonally parallel to the left and right. The purity and recovery of R 'outlets separated at different switching times are calculated, and then a better switching time is determined. According to the result of step (1), reduce the difference between m4 and m2 to increase the purity, or increase the difference between m4 and m2 to increase the recovery rate. By increasing m1, you can increase the recovery rate and increase the efficiency of the stationary phase.

In summary, the tandem simulated moving bed system of this case uses the side flow pipeline to connect the first and second stage simulated moving beds in series to separate the intermediate components with the retention constant in the middle. Since the simulated moving bed will have concentration fluctuations when switching these pipe columns to different sections, the concentration fluctuations in the lateral flow of the side flow pipeline have a great impact on the separation effect of the second stage simulated moving bed. In order to reduce the The concentration fluctuates. In this case, a buffer tank is installed on the side stream pipeline. The medium and high retention components will enter the buffer tank first in the side stream pipeline. After the concentration in the buffer tank stabilizes, it will flow to the second stage simulation movement. Bed, so that the second-stage simulated moving bed has better separation effect. In addition, the tandem simulated moving bed system in this case further includes a regeneration section. The stationary phase of the first section of the first-stage simulated moving bed is cleaned and recycled back to the second-stage simulated moving bed after the regeneration section, without The retentive components are carried to the second-stage simulated moving bed, which can timely and effectively discharge the strong retentive components, so that the tandem simulated moving bed system can be used for a long time. In addition, the design of the regeneration section can also avoid the need to increase the velocity of the side stream in order to ensure the function of the second-stage simulated moving bed, which can more conveniently set the operating conditions. This case further provides a multi-component chromatography separation method applied to the above-mentioned tandem simulated moving bed system.

Although this case has been disclosed as above with examples, it is not intended to limit this case. Any person with ordinary knowledge in the technical field can make some modifications and retouching without departing from the spirit and scope of this case, so the protection of this case The scope shall be determined by the scope of the attached patent application.

A: first component (group) B: second component (group) C: third component (group) D1: first direction D2: second direction L1, L2: washing liquid 100: tandem simulated moving bed system 110: The first stage simulated moving bed Z1: the first section Z2: the second section Z3: the third section 120: the second stage simulated moving bed Z4: the fourth section Z5: the fifth section 130: the regeneration section Z6 : Sixth section 132: Wetting zone 134: Strong cleaning zone 140: Side flow line 142: Side flow inlet 144: Side flow outlet 150: Liquid concentration uniformity module 152: Buffer tank 155: Side flow pressure regulator 157 : Side flow pump 160: central valve group 162: first part 164: first passage 166: second part 168: second passage 170: liquid supply tank 172: mainstream pump 174: liquid recovery tank 176: mainstream pressure regulator 180: Column 200: Multi-component chromatography separation method 210 ~ 240 of a tandem simulated moving bed system: steps

FIG. 1 is a schematic diagram of a tandem simulated moving bed system according to an embodiment of the present invention. FIG. 2 is a schematic diagram of the next sequence of the tandem simulated moving bed system of FIG. 1. 3 is a schematic flowchart of a multi-component chromatography separation method of a tandem simulated moving bed system according to an embodiment of the present invention. FIG. 4 is a schematic diagram of the piping of FIG. 1. 5 is a schematic cross-sectional view of a central valve group of the tandem simulated moving bed system of FIG. 1. Fig. 6 is a schematic cross-sectional view taken along the line A-A of Fig. 5. Fig. 7 is a schematic cross-sectional view taken along the line B-B in Fig. 5. 8 to 11 are the second and third relative flow rates m2 and m3 of the second and third sections of the tandem simulated moving bed system of FIG. 1, and the fourth and fifth relative flow rates m4 of the fourth and fifth sections And m5.

A: first component (group) B: second component (group) C: third component (group) D1: first direction D2: second direction L1, L2: washing liquid 100: tandem simulated moving bed system 110: The first stage simulated moving bed Z1: the first section Z2: the second section Z3: the third section 120: the second stage simulated moving bed Z4: the fourth section Z5: the fifth section 130: the regeneration section Z6 : Sixth section 132: Wetting zone 134: Strong cleaning zone 140: Side flow line 142: Side flow inlet 144: Side flow outlet 150: Liquid concentration uniformity module 152: Buffer tank 155: Side flow pressure regulator 157 : Side-flow pump 180: Tubing

Claims (7)

A simulating moving bed system in series is suitable for separating a mixture. The mixture includes a first component (group), a second component (group), and a third component (group), each having a first retention constant and a second component from small to large. The retention constant and the third retention constant. The tandem simulated moving bed system includes: a first-stage simulated moving bed including first, second, and third sections arranged along a first direction; a second-stage simulated moving bed including The fourth and fifth sections arranged in the first direction, the first and the second-stage simulated moving beds are respectively composed of a mobile phase and a stationary phase, and the mobile phases are respectively moved in the first and the second-stage simulated mobile beds. The bed flows in a first direction, and the stationary phase simulates movement in a second direction opposite to the first direction with respect to the mobile phase; a lateral flow pipeline is connected to the first and second-stage simulated moving beds and includes A side flow inlet and a side flow outlet, wherein the side flow inlet is connected between the first section and the second section, and the side flow outlet is connected between the fourth section and the fifth section A buffer tank configured on the side stream line; A pressure regulator is arranged on the side flow line and is located between the buffer tank and the side flow outlet; a side flow pump is arranged on the side flow line and is located between the buffer tank and the side flow pressure regulator And a regeneration section, which is a sixth section, arranged along the first direction beside the fifth section and includes a wetting zone and a strong cleaning zone, wherein the first-stage simulated moving bed is suitable for separating the mixture The first component (group), the second and third components (group) of the mixture are adapted to pass from the second section along the side flow line through the buffer tank, the side flow pump, and the side flow pressure The regulator moves between the fourth section and the fifth section, and is separated in the second-stage simulated moving bed. The tandem simulated moving bed system described in item 1 of the patent application scope further includes: a central valve group including a first part and a second part, wherein the first part is selectively rotatable relative to the second part along an axis to Switching the alignment state between the plurality of first channels of the first part and the plurality of second channels of the second part, some of the second channels are respectively connected to some of the second channels are respectively connected to the first 1. The second, the third, the fourth, the fifth and the sixth sections. The serial simulated moving bed system described in item 2 of the scope of patent application, further comprising: a plurality of liquid supply tanks respectively connected to some of the first channels, and the mobile phase includes at least one flushing liquid, each of the liquid The supply tank contains the at least one flushing liquid; a plurality of mainstream pumps are respectively connected to the liquid supply tanks and the partial first channels; a plurality of liquid recovery tanks are respectively connected to part of the first channels and It is suitable for accommodating the at least one washing liquid; and a plurality of mainstream pressure regulators are respectively connected to the liquid recovery tanks and the partial first channels. As described in the patent application scope item 3, the number of the liquid supply tanks and the mainstream pumps are five, and the five liquid supply tanks and the five mainstream pumps are respectively connected to the The source of the first section, between the second section and the third section, the source of the fourth section, the wetting zone and the strong cleaning zone. The serial simulated moving bed system according to item 3 of the patent application scope, wherein the number of the liquid recovery tanks and the mainstream pressure regulators are two, the two liquid recovery tanks and the two mainstream pressure regulators Connected to the end of the third segment and the end of the fifth segment, respectively. The tandem simulated moving bed system according to item 1 of the scope of patent application, wherein the first, the second, the third, the fourth, the fifth and the sixth sections each include at least one pipe string Each column is filled with the stationary phase having pores inside the particle. The tandem simulated moving bed system according to item 1 of the patent application scope, wherein the mobile phase flows through the first, the second, the third, the fourth, the fifth section and the first direction in the first direction. The strong cleaning area of the sixth section flows through the wetting area of the sixth section in the second direction.