KR101106004B1 - A simulated moving bed separation apparatus and a separative method of a fluid using the same - Google Patents

Abstract

The present invention is a pseudo moving bed separation apparatus and a method for separating fluid using the same, and more specifically, for the separation of para-xylene by the pseudo moving bed method, it is easy to install as many multi-position valves as the number of beds on the adsorption column. It relates to a technology that enables the inflow of raw materials and the outflow of recovered fluid. According to the pseudo mobile bed separation apparatus and the fluid separation method using the same according to the present invention, it is possible to significantly improve the operation reliability, operational flexibility, new inflow and outflow applicability compared to the conventional similar mobile bed separation process.

Pseudo mobile bed separation, para-xylene, multi-position valve

Description

Pseudo mobile bed separation device and fluid separation method using the same {A SIMULATED MOVING BED SEPARATION APPARATUS AND A SEPARATIVE METHOD OF A FLUID USING THE SAME}

The present invention is a simulated moving bed (SMB) separation apparatus and a separation method of a fluid using the same, more specifically, for the separation of para-xylene (p-xylene, PX) by the pseudo moving bed method, The present invention relates to a technology that enables the inflow of raw materials and the outflow of recovered fluid by installing a multi-position valve (MPV) as many as the number of beds on an adsorption tower.

1. Overview of SMB Process for PX Separation

Commercially used PX adsorptive separation SMB processes are roughly divided into UOP's Parex process and IFP's Eluxyl process. Toray's AroMax process has also been released, but is similar to the IFP's erucyl process, except that the adsorption bed is horizontal. Each SMB method does not show a big difference in mechanical aspects except for inflow of raw materials and outflow of recovered fluid. For details of the Parex process, see Korean Patent Application Nos. 10-2005-0129459 and 10-2005-0129457.

2. SMB process using a single rotary valve

1 shows a schematic of an SMB process using a single rotary valve, such as the Parex process.

As shown in Fig. 1, a bed is formed in multiple layers in the SMB process adsorption chamber 6 using a single rotary valve, and each bed is filled with an adsorbent. Each bed in the adsorption chamber 6 is connected to the rotary valve 5 via multiple access lines B1-B8.

Rotary valves 5 in the SMB process using a single rotary valve are provided with feed (fluid mixture) inlet port (1), desorbent inlet port (2), extract outlet port (3), raffinate port (4). Connect two inlet ports and two outlet ports to each of the multiple access lines (B1 to B8). The detailed configuration of the rotary valve 5 can be easily implemented by those skilled in the art.

SMB process using a single rotary valve is configured by dividing the adsorption chamber 6 into several beds (Bed 1 to 8) and connected in series with each other. In the pseudo mobile bed adsorptive separation process, there is practically no flow of the fixed phase, and the mobile phase flows through the port positions of the desorbent, extract, feed, and raffinate according to the switching interval of a certain time. In the direction of change, the column is placed in a direction opposite to the direction in which the mobile phase flows relative to each port. In this way, a virtual stationary phase flow can be created to simulate the mobile phase and countercurrent flow. The adsorbent used as the stationary bed is filled in the bed.

It is not possible to move the position of each of the ports (1, 2, 3, 4) of the feed, desorbent, extract and raffinate continuously, but as shown in Figure 1 by installing multiple access lines (B1 ~ B8) By providing a switching time through the rotary valve 5, the same effect can be obtained by periodically moving each flow to a neighboring line. Accordingly, the material having weak adsorptive power among the material injected through the feed (fluid mixture) inlet port 1 comes out to the raffinate outlet port 4 along the mobile phase, and the material having high adsorptive power is applied to each of the adsorption chamber 6. Adsorbed by the adsorbent in the bed (Bed 1 ~ 8) is used to come out to the extract outlet port (3) after a period of time according to the switching of a certain time.

In the SMB process using a single rotary valve, the feed of raw materials and desorbents and the discharge of extracts and raffinates are all carried out through the same pipe. Multiple access lines B1 to B8 connecting the adsorption tower and the rotary valve exist as many as the number of beds in the adsorption tower and are also called bed lines. According to the operating procedure of the SMB, certain pipes are used for the extraction of extracts after a certain period of time after they have been used for raw material injection. At this time, the initial amount of the extract discharged during the switching time is mixed with the raw material filled in the pipe, so that the purity of the extract is slightly reduced. As a measure to prevent this, a procedure called line flush and secondary flush has been added, and the details of this are described in Korean Patent Application Nos. 10-2005-0129459 and 10-2005-0129457, etc. See. Recently, a tertiary flush procedure was added to further improve the adsorptive separation performance. For details, refer to Korean Patent Application No. 10-2007-7022602.

3. SMB process using multiple on-off valves

2 shows a schematic diagram of an SMB process using several on-off valves, such as an eruscil process.

As shown in FIG. 2, a bed is formed in multiple layers in the SMB process adsorption chamber 6 using several on-off valves 13, and each bed is filled with the adsorbent. Each bed in the adsorption chamber 6 is connected to each port 1, 2, 3, 4 via multiple access lines B1-B32 and flow-specific heads 9, 10, 11, 12. .

On-off valves 13 of the SMB process using several on-off valves 13 are provided with feed (fluid mixture) inlet ports (1), desorbent inlet ports (2), extract outlet ports (3), As many as the number of multiple access lines on the two inlet ports and two outlet ports, such as the raffinate port 4, and the multiple access lines B1 to B32 connecting the adsorption beds with the corresponding heads 9, 10, 11 and 12 It can be installed to implement SMB operation.

The detailed operation of the SMB process using several on-off valves is the same as the SMB process using the single rotary valve of item 2 above. However, in the case of SMB process using a single rotary valve, each flow is moved to a neighboring line periodically by a constant switching time interval through the rotary valve, whereas in the SMB process using multiple on-off valves In this case, there is only a difference in that each flow is periodically moved to a neighboring line through opening and closing of the on-off valve.

SMB processes using multiple on-off valves, in principle, involve the injection of raw materials and desorbents and the discharge of extracts and raffinates through different piping. Thus, in principle, no separate cleaning process is required for the bed line, such as for SMB processes using a single rotary valve. However, in the case of the erucyl process, as described in Korean Patent Application No. 10-2005-0043669, the injection of raw materials and desorbents is carried out using the same injection line, and the extraction and extraction of raffinate are carried out using the same discharge line. Therefore, there is an example of performing the cleaning by using a separate bypass line (by-pass line).

4. SMB process using as many MPVs as inflow and outflow

3 shows a schematic diagram of an SMB process using as many MPVs as inflow and outflow flows. As shown in FIG. 3, the number of inflow and outflow streams such as a feed (fluid mixture) inlet port 1, a desorbent inlet port 2, an extract outlet port 3, a raffinate port 4, etc. The MPVs 14, 15, 16, and 17 are connected to each bed in the adsorption chamber 6 through the multiple access lines B1 to B32 to implement the SMB operation. For a detailed description of this, refer to Korean Utility Model Application No. 20-2000-0014507.

The detailed operation of the SMB process using as many MPVs as the inflow and outflow flows is the same as the SMB process using a single rotary valve or the SMB process using several on-off valves. However, in the case of the SMB process using a single rotary valve, each flow is periodically moved to a neighboring line by giving a certain switching time interval through the rotary valve, and in the case of the SMB process using several on-off valves In the case of SMB process using the number of inflow and outflow flows, the flow of MPV in each inflow and outflow flow is periodically moved to the adjacent line by opening and closing the on-off valve. The only difference is that they periodically move each flow to a neighboring line.

5. Limitations of Prior Art

In the case of the SMB process using a single rotary valve, the process configuration is simple and the operation reliability is high by using a single rotary valve, while the operating flexibility is inferior. That is, the number of beds (number of beds per zone) between each inlet and outlet port cannot be changed without hardware correction of the rotary valve. In addition, hardware correction of the rotary valve is also required to implement a dual feed operation (Korean Patent Application No. 10-2008-0023297) using two raw materials having different concentrations. In addition, by sharing the same bed line with each other for inflow and outflow, the process configuration is simplified, but the separation efficiency is reduced, and the advantages of the simple process configuration are impaired by adding complicated washing procedures to prevent the same. There was this. In addition, the SMB process using a single rotary valve is a Varicol operating method (Korean J. Chem. Eng., 21 (2), 454-464, 2004, which is evaluated to be superior to the conventional SMB method). It is also impossible to implement it.

In addition, the SMB process using several on-off valves has excellent operating flexibility, but using a large number of on-off valves reduces operating reliability due to the increased possibility of malfunction of the on-off valves. have. In order to compensate for this, the SMB process using several on-off valves has as many stand-by on-off valves as the number of on-off valves in use, but it is disadvantageous in terms of cost. have. In order to implement dual feed operation using two raw materials of different concentrations (Korean Patent Application No. 10-2008-0023297), an additional on-off valve must be installed on each bedline and as many bed lines as the number of beds. There was a problem.

Finally, the SMB process using as many MPVs as the inflow and outflow streams has excellent operating reliability and operational flexibility, while additional MPVs need to be installed when adding new inflows and outflows. In addition, in order to implement a dual feed operation (Korean Patent Application No. 10-2008-0023297) using two raw materials having different concentrations, there was a problem in that an additional MPV should be installed.

The present invention has been made to solve the problems of the prior art as described above, the problem to be solved by the present invention is to install the number of MPV as the number of beds in the adsorption tower for fluid separation by the SMB method, overall reliability, operation It is an object of the present invention to provide a pseudo mobile bed separation device and a separation method using the same, which have remarkably improved flexibility and novel inflow and outflow applicability.

Similar moving bed separation device of the present invention for solving the above problems is the inlet and outlet port of the fluid is connected to the multi-position valve, the multi-position valve is connected to a plurality of beds sequentially arranged on the adsorption tower The multi-position valve is characterized in that a plurality of the number of the bed is connected to each of the beds.

It is preferable that the inflow and outflow ports of the fluid of the pseudo mobile bed separation apparatus of the present invention are plural.

In the similar moving bed separation apparatus of the present invention, in order to prevent contamination between the fluids due to the flow of the fluid, it is preferable that the flush in line and the flush out line are additionally connected to the multi-position valve.

In addition, the fluid separation method of the present invention for solving the above problems is to use the similar moving bed separation apparatus of the present invention described above, the flow of fluid between the inlet and outlet ports of the fluid and each bed is multi-position Through the circular rotation of the valve is characterized in that the connection between the inlet and outlet ports of the fluid and each bed is made to move sequentially.

The separation method of the fluid of the invention is preferably separation of para-xylene.

According to the pseudo mobile bed separation apparatus and the fluid separation method using the same according to the present invention, it is possible to significantly improve the operation reliability, operational flexibility, new inflow and outflow applicability compared to the conventional similar mobile bed separation process.

According to the present invention, there is provided a pseudo mobile bed separation apparatus and method, characterized in that as many MPVs as the number of beds in the adsorption tower for PX separation by the SMB method. In the quasi-mobile bed separation apparatus according to the present invention, in the SMB process, the inflow stream of the feed, the desorbent, and the like and the outflow stream of the extract, the raffinate, and the like flow through the MPV attached to each bed, and the circulation of the MPV. It is configured a pseudo moving bed separation process in which the inlet and outlet positions of each raw material and the recovered fluid are changed on the adsorption tower according to the rotation.

Figure 4 shows a schematic diagram of one embodiment of a pseudo moving bed separation apparatus according to the present invention. Here, two inflows such as feed and desorbent, two outflows such as extract and raffinate, and four inflow and outflow streams for the eight-bed SMB process, respectively. The case of a pseudo mobile bed separation process is described in which the inlet and outlet locations of each raw material and recovery fluid are changed into and out of the adsorption tower according to the circulation of MPV by connecting to each bed of the adsorption tower through eight bed lines.

Hereinafter, the raw material inlet and recovery fluid outlet device of the pseudo moving bed separation process according to the present invention will be described in more detail with reference to FIGS. 4 to 14.

According to FIG. 4, the feed (fluid mixture) inlet port 1, the desorbent inlet port 2, the extract outlet port 3, and the raffinate port 4 are attached to as many MPVs 18-25 as the number of beds. It is connected through the multiple access lines (B1 ~ B32), each MPV is connected to each bed in the adsorption chamber (6) through the connection line (26 ~ 33) to implement the SMB operation method.

The detailed operation of the SMB process using the number of MPVs in the bed is as follows: SMB process using a single rotary valve, SMB process using several on-off valves, SMB process using as many MPVs as inlet and outlet flows And the same. However, in the case of the SMB process using a single rotary valve, each flow is periodically moved to a neighboring line by a given switching time interval through the rotary valve, and in the case of the SMB process using several on-off valves In the SMB process using the number of inflow and outflow flows, the flow of MPV is rotated by each inflow and outflow flow. While the SMB process using the MPV as many as the number of beds of the present invention periodically moves each flow periodically through the circular rotation of the MPV for each bed There is a difference in that it moves to.

5 to 12 are conceptual diagrams of a phenomenon in which pseudo mobile floor operation is implemented by the operation of the MPV. 5, the feed is introduced into the adsorption tower No. 1 bed, the desorbent is introduced into the adsorption tower No. 5 bed, the extract is discharged from the adsorption tower No. 7 bed inlet, the raffinate is discharged from the adsorption tower No. 3 bed inlet. After a certain switching time, as shown in FIG. 6, the feed enters the adsorption tower No. 2 bed, the desorbent enters the adsorption tower No. 6 bed, the extract is discharged from the inlet of the adsorption tower No. 8 bed, the raffinate is adsorption tower No. 4 Outflow from bed inlet As such, the inlet and outlet ports are moved forward by one bed by the circular rotation of the MPV, thereby implementing typical SMB operation. Advancement of the position of the inlet and outlet ports similar to FIGS. 7-12 is repeated. After having the positions of the inflow and outflow ports shown in FIG. 12, after a certain switching time has elapsed, the flow returns to the positions of the inflow and outflow ports as shown in FIG. 5, and the position movement is repeated indefinitely.

FIG. 13 is a flush in port for each of the inflow and outflow flows that may arise from the configuration shown in FIG. 4 to eliminate some cross-contamination as sharing the connection line between the MPV and each bed. (34) and the flush out port (35) is installed. With the possibility of additional inflows and outflows in mind, it is advisable to keep the MPV ahead of the number of flows in use. It is preferable to perform the flush in immediately after the feed injection of the desorbent or PX, and the flush out is preferably performed immediately before the extraction of the extract.

When dual feed operation is applied, the additional feed inlet port as shown in FIG. 14 is eliminated without the need for complex hardware calibration, such as an SMB process using a single rotary valve or an SMB process using multiple on-off valves. 38) only need to be installed.

Hereinafter, the present invention will be described in more detail by way of examples.

[Example]

FIG. 15 compares the PX recovery of the conventional SMB process using a single rotary valve and the SMB process using MPV as many as the number of beds according to the present invention. As with the actual Parex process, the total number of beds is 24, and the SMB process using a single rotary valve reduces the volume of each bedline that shares inflow and outflow flows between the rotary valve and the bed by 0.72 m ³ , per bed. In the case of applying MPV, the volume of each bedline sharing inflow and outflow between MPV and bed is assumed to be 0.1m ³ . In the case of maintaining the maximum flow rate in the adsorption tower, which is known to have the greatest effect on the adsorbent life in the adsorption tower operation, the PX recovery rate can be obtained by adjusting only A / Fa and L2 / A, which are the main operating variables, to obtain the same product purity. In comparison, the PEX recovery rate was 96.2% for the Parex method, while the PX recovery rate of the SMB process using the MPV as many as the number of beds exceeded 99%.

The SMB process using several on-off valves shows the same level of PX recovery as the SMB process using MPV as the number of beds according to the present invention. In terms of applicability, an SMB process using as many MPVs as the number of beds according to the present invention exhibits significantly better performance.

1 is a schematic diagram of a conventional SMB process using a single rotary valve.

2 is a schematic diagram of a conventional SMB process using several on-off valves.

3 is a schematic diagram of a conventional SMB process using as many MPVs as inflow and outflow flows.

4 is a schematic diagram of an SMB process of the present invention using as many MPVs as the number of beds.

5 to 12 are conceptual diagrams of a phenomenon in which similar mobile floor operation is implemented by the operation of the MPV of the present invention.

FIG. 13 is a schematic diagram illustrating a case where a flush in port and a flush out port are applied to an SMB process of the present invention using as many MPVs as the number of beds.

14 is a schematic diagram when dual feed operation is applied to an SMB process of the present invention using as many MPVs as the number of beds.

FIG. 15 is a graph comparing the PX recovery rate between the conventional SMB process using a single rotary valve and the SMB process of the present invention using MPV as many as the number of beds. The dashed line represents a conventional SMB process using a single rotary valve and the solid line represents the SMB process of the present invention.

<Explanation of symbols>

1 --- feed inlet port

2 --- desorbent inlet port

3 --- extract outflow port

4 --- Laffinate port

5 --- rotary valve

6 --- Sorption Tower

7 --- Adsorption tower circulation pump

8 --- Adsorption Tower Circulation Line

9-12, 36, 37, 39 --- head

13 --- on-off valve

14-25 --- multi-position valve

26 ~ 33 --- connection line

34 --- flush in line

35 --- Flush Outline

38 --- Feed Inlet Port 2

Claims (5)

A fluid inlet and outlet port is connected with a multi-position valve, and the multi-position valve is connected with a plurality of beds sequentially arranged in an adsorption tower, wherein the multi-position valve is the number of beds A plurality of mobile bed separation apparatus, characterized in that there are a plurality of connected to each of the beds. The apparatus of claim 1, wherein the inflow and outflow ports of the fluid are plural. The device of claim 1, wherein the flush in line and the flush out line are further connected to a multi-position valve to prevent contamination between the fluids due to the flow of the fluid. A method of separating a fluid using the quasi-mobile bed separation apparatus according to any one of claims 1 to 3, wherein the flow of fluid between the inlet and outlet ports of the fluid and each bed is carried out through the circular rotation of the multi-position valve. And a connection between the outlet port and each bed is sequentially moved. 5. The method of claim 4, wherein said separation of fluid is separation of para-xylene.

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