JPH0779925B2 - Pressure crystallizer and method - Google Patents

Description

FIELD OF THE INVENTION The present invention relates to pressure crystallizers and methods.

(Prior Art) The pressure crystallization method has great potential for application to a raw material system that is difficult to separate by the conventional distillation method or cooling crystallization method, that a high-purity product is easily obtained, and It is a separation and purification technology that has been attracting a great deal of attention as the chemical industry has become finer in recent years because of its easy yield and low energy consumption.

A typical example of the conventional apparatus used for such pressure crystallization method is shown in FIG. In FIG. 11, (1) is a pressure-resistant cylindrical body that constitutes a pressure-resistant container, (2) is a cylindrical filter for separating individual liquid disposed on the inner peripheral wall of the cylindrical body (1), and (3) is a pressure-resistant container. A lid tightly fitted in the lower opening of the flexible cylinder (1), (4) a pressurizing / squeezing piston fitted from the upper opening of the pressure resistant cylinder (1), and (5) a raw material. Supply line, V ₁ is a feed valve, (6) is a drain passage, V ₂ is a drain valve, (7) is a pusher for taking out crystallization, and (8) is a chute for taking out crystallization. It is a thing.

A typical example of the procedure for performing pressure crystallization using the apparatus shown in FIG. 11 will be described below.

(A) With the drainage valve V ₂ closed, the liquid feed valve V ₁ is opened to feed the raw material from the raw material supply pipe (5) into the pressure resistant cylinder (1).

(B) When the supply is completed, the liquid supply valve V ₁ is closed, and in that state, the piston (4) is lowered to apply a high pressure to the raw material in the pressure resistant cylinder (1) to promote crystallization of a specific component. Let

(C) When crystallization is completed, the drain valve V ₂ is opened, and the liquid phase is discharged under pressure to separate the individual liquid. In the usual case, after the separation, the solid phase in the container is further squeezed to discharge the residual liquid (hereinafter, squeezing is also referred to as individual liquid separation when the squeezing is performed in this way). In some cases, the pressing is not performed.

In the solid-liquid separation step, pressure is applied to the pressure-resistant cylindrical body (1) to discharge the liquid substance through the filter (2). This liquid substance is discharged from the gap provided on the back side of the filter (2) through the drainage passage (6) of the lower lid (3).

(D) After solid-liquid separation, as shown in FIG. 12, the pressure-resistant cylinder (1) is raised to open the inside of the cylinder (1), and then the chute (8) is advanced and the pusher (7) is moved. And the crystallization product (solid phase component) C is taken out.

After the step (d) is completed, the process returns to the step (a) again, and this operation is repeated to separate the specific component.
Recovery is continuous.

(Problems to be Solved by the Invention) However, in the conventional pressure crystallization apparatus and method as described above, when performing solid phase fractionation in the step (d),
Since the opening of the cylindrical body (1) and the advance of the chute (8) and the pusher are required as described above, there is a problem that it takes a considerably long time to take out the solid phase. In addition, solid phase extraction requires retreating of the chute (8) and pusher (7), lowering of the tubular body (1) and fitting with the lower lid (3).
This also takes quite a long time. The above problems lead to the problem that the time required for the repeated operation cycle becomes long and the productivity deteriorates.

During the solid phase extraction, the residual liquid (containing impurities) in the tube (1) is dripped and solidified between the start of the rising of the tube (1) and the completion of the extraction of the solid phase. There is a problem that the purity of the solid phase component (product) decreases because it falls on the phase component.

Furthermore, when the amount (concentration) of the solid phase component in the mixture in the solid-liquid coexisting state after crystallization is low (for example, 25% or less), the height of the solid phase component after the solid-liquid separation becomes low, There is a problem that the solid phase extraction cannot be performed easily. In addition, when the crystal grain size of the solid phase component is small (as observed in the pressure crystallization of aliphatic compounds) or when the purity of the solid phase component (product) is low, the solid phase after solid-liquid separation The phase component becomes soft or semi-solid like a sherbet, and in such a case, it is extremely difficult to take out the solid phase fraction without introducing impurities.

The present invention has been made in view of such circumstances, and its purpose is to solve the problems such as three or more of the conventional ones, shorten the solid phase extraction time, and reduce the number of repeated operation cycles. If the required time can be shortened, the product purity can be improved, and the height of the solid phase after solid-liquid separation becomes low,
An object of the present invention is to provide a pressure crystallization apparatus and a method capable of facilitating solid phase extraction even when the solid phase becomes soft or semi-solid.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a pressure crystallization apparatus and method having the following configurations.

That is, in the device according to the present invention, the pressure-resistant cylindrical body, the first piston that advances and retracts the cylindrical body from the one side opening of the cylindrical body, and the forward and backward movement of the cylinder inside the other side opening of the cylindrical body. A pressure crystallizer having a second piston, and a filter for discharging a liquid phase component arranged in the cylinder and / or on the piston pressing surface, wherein the pressure-resistant cylinder penetrates the cylinder wall. The pressure crystallizer is characterized in that a solid phase extraction hole is provided.

In the method according to the present invention, a container is formed by inserting a first piston and / or a second piston into a pressure resistant cylinder, and a raw material is supplied to the container and pressurized to form a mixture in a solid-liquid coexisting state. A method for pressure crystallization in which a liquid phase component is continuously discharged under pressure from the container for solid-liquid separation, and then a solid phase component is taken out of the container, wherein the solid phase component is removed by a first piston and a second piston. The pressure crystallization method is characterized in that the solid phase component is taken out by moving it to a solid phase fraction extraction hole of the pressure-resistant cylinder and extruding from the hole.

(Operation) As described above, the pressure crystallizer according to the present invention includes a pressure-resistant cylindrical body (hereinafter referred to as a cylindrical body) having a solid-phase extraction hole, and a first piston that moves forward and backward in the cylindrical body. And a second piston, and a filter for discharging a liquid phase component is arranged inside the cylinder and / or on the piston pressing surface.
Therefore, when the first piston and / or the second piston is inserted into the cylinder to form a container and the raw material is supplied to the container, the raw material can be pressurized. Therefore, a solid-liquid coexisting mixture is formed, and solid-liquid separation is possible.

The container formation and the raw material supply can be performed as follows. That is, when the device is vertical (the axis of the pressure-resistant cylinder is vertical) and the solid-phase extraction hole (hereinafter referred to as the extraction hole) is on the upper part of the cylinder, the lower piston is placed on the lower part of the cylinder. If the extraction hole is located in the lower part of the cylinder, the lower piston is inserted to the position where the hole is closed, and then the raw material is injected.

If the device is horizontal and the extraction hole is on the right side of the cylinder, insert both left and right pistons to the position where the extraction hole is not closed,
After injecting the raw material from the take-out hole, insert the right piston to the position where the take-out hole is closed. When the piston has a raw material supply pipe passing through it, both pistons are inserted (the right piston is inserted to the extraction hole closing position), and then the raw material is injected from the raw material supply pipe.

After the solid-liquid separation, the first piston and the second piston move the solid-phase component to the extraction hole portion of the cylindrical body, and when a force is applied to the solid-phase component, the solid-phase component can be pushed out from the hole and taken out. At this time, when the solid phase is a soft one, like a fluid, when the solid phase is a hard solid, the solid is crushed and extruded.

The movement of the solid phase component to the extraction hole portion can be performed, for example, while sandwiching the solid phase component with the first piston and the second piston, and can be instantaneously and easily performed. The time required for extrusion can be shortened by increasing the piston pressure and / or increasing the cross-sectional area of the lateral hole. Therefore, the solid phase extraction time can be shortened.

After taking out the solid phase, the container can be formed and the raw material can be supplied by moving the piston. This piston movement can also be performed instantly and easily.

Therefore, the time required for repeated operation cycles can be shortened,
You can improve productivity.

Further, since the solid phase can be moved and extruded while sandwiching the solid phase with the piston as described above, it is possible to take out the solid phase without dropping the residual liquid to the product and improve the product purity. become.

Further, as described above, the solid phase extraction can be performed by moving the solid phase to the extraction hole and extruding, and the height of the solid phase does not affect the operability of these. Also, the properties of the solid phase component (hardness, etc.) affect the extrudability, and it becomes difficult to extrude when the solid phase component is hard, but in such a case, extruding can be facilitated by increasing the pressure applied by the piston. Like
Therefore, when the height of the solid phase after solid-liquid separation becomes low,
Even if the solid phase is soft or semi-solid, the solid phase can be easily taken out.

Furthermore, if a solid phase extraction pipe directly connected to the product storage is connected to the extraction hole, the solid phase can be recovered without being contaminated with dust in the atmosphere. Further, since the atmosphere in the storage and the take-out pipe can be adjusted, even in the case of a substance that dislikes the atmosphere (solid phase content), the solid phase content can be recovered without contact with the air.

In the pressure crystallization method according to the present invention, pressure crystallization is performed by the same operation as the operation described in the above description. That is, the container is formed by inserting the first piston and / or the second piston into the cylindrical body, the raw material is supplied to the container, and the mixture is pressurized to form a mixture in a solid-liquid coexisting state. Of the solid phase is discharged to the outside of the container for solid-liquid separation, and then the solid phase is moved by the first piston and the second piston to the take-out hole of the cylindrical body and pushed out from the hole to take out the solid phase. I am trying to do it. Therefore, the same effect as the above can be obtained, and the productivity and the product purity can be improved.

The extraction hole can also be used as a raw material supply port as described above. The cross-sectional area of the holes can be large enough. Therefore, when the raw material is supplied from the hole, the raw material supply time can be shortened,
Further, when the raw material is supplied in the form of a slurry, it becomes possible to eliminate the blockage accident of the raw material supply line which is often experienced in the conventional apparatus.

The shape of the inner surface of the cylinder is most preferably circular from the viewpoint of pressure resistance, but is not particularly limited.

The cylinder may be fixed and both pistons may be movable, one piston may be fixed and the cylinder and the other piston may be movable, or both the cylinder and both pistons may be movable.

The means for moving the piston, cylinder, etc. forward and backward is a hydraulic cylinder,
Other advancing / retreating means such as a solenoid mechanism can be adopted.

(Example) Example 1 FIG. 1 shows a cross-sectional view of a main part of a pressure crystallizer according to Example 1. This device is vertical. In FIG. 1, (11) is a cylindrical body, and a cylindrical filter (12) is arranged on the inner surface side thereof. A take-out hole (13) is provided in the lower portion of the tubular body (11) at a position away from the installation portion, and a product take-out pipe (14) is connected to the take-out hole (13).

An upper piston (10) and a lower piston (15) are arranged on the upper and lower parts of the tubular body (11). (9) and (16) are cylinders of upper and lower pistons.

The lower piston (15) has a filter (19) on its pressing surface.
And the drainage passage (2
0) is arranged. (17) is a raw material supply pipe, (18) is a heating heater, and is a cylinder (11) and a product take-out pipe (1
It is arranged in part 4).

Pressure crystallization was performed using the above apparatus. The main steps of this pressure crystallization are shown in FIGS. First, the lower piston (15) is placed in the cylinder (11) by a hydraulic cylinder (not shown).
Was advanced until its upper surface was positioned higher than the lower end of the cylindrical filter (12), the extraction hole (13) was closed, and a container was formed.

Next, withdraw the upper piston (10) from the tubular body (11),
After opening the upper part of the cylindrical body (11), as shown in FIG. 2, the raw material was supplied from the raw material supply pipe (17) into the formed container.

After feeding the raw material, as shown in Figs.
(0) is inserted into the cylinder (11), the raw material in the container is pressurized to 1400 atm, and after 5 seconds, the valve in the drainage passage (20) is opened to maintain the liquid pressure in the container at 1400 atm. The phase components were discharged outside the container. Subsequently, the solid phase component in the container was squeezed to discharge the residual liquid, and the pressure in the container was gradually reduced to purify the solid phase component, and a vacuum perspiration treatment was performed.

After the above sweating treatment, the solid phase component is sandwiched between the upper piston (10) and the lower piston (15), and the solid phase component is extracted into the extraction hole (13) while maintaining a pressure equal to or higher than the melting pressure of the solid phase component. I moved it. Then, as shown in FIGS. 5 and 6, the lower piston (1
While 5) is stopped, lower the upper piston (10), push out while crushing the solid phase component from the extraction hole (13), and extract the solid phase component (product) C through the product extraction pipe (14). It was

After taking out the solid phase, the valve of the drainage passage (20) is closed, the upper piston (10) is withdrawn from the cylindrical body (11), and then the lower piston (15) is fitted with a cylindrical filter (12) having an upper surface. ) To a position higher than the lower end, and the extraction hole (13) was closed to form a container. By this operation, the state before injection of the raw material was obtained, and subsequently, by the same procedure as described above, supply of the raw material into the container, pressurization, solid-liquid separation and solid-phase separation were carried out, and this series of operations was repeated.

As a result, compared to the conventional case, the time required for the repeated operation cycle was significantly shortened (40 to 50%). Also,
Product purity has been improved.

The steps of supplying the raw material, pressurizing, discharging the liquid phase, and compressing the solid phase can be repeated several times. After that, when the product is taken out under reduced pressure perspiration, the product yield is increased. improves. In particular, it was confirmed that this method is effective when the solid phase concentration in the raw material is low, and the product yield is significantly improved.

Example 2 FIG. 7 shows a cross-sectional view of a main part of a pressure crystallizer according to Example 2. As shown in FIG. 7, a raw material supply pipe (21) having a check valve (22) is arranged in the upper piston (10) through the inside of the piston. Other than this, the pressure crystallizer according to Example 1 is the same.

With the upper piston (10) still inserted in the cylinder (11),
The lower piston (15) was advanced, the extraction hole (13) was closed, a container was formed, and then the raw material was supplied from the raw material supply pipe (21). After supplying the raw materials, the same pressurization, solid-liquid separation, and solid-phase component extraction as in Example 1 were performed.

After the solid phase is taken out, the upper piston (10) and the lower piston (15) are moved to form a container, and the steps from raw material supply to solid phase extraction are carried out in the same procedure as described above. The operation was repeated.

As a result, as compared with the case of the first embodiment, it is not necessary to withdraw and insert the upper piston (10) with respect to the cylindrical body (11) at the time of supplying the raw material, so that the time required for the repeated operation cycle is further shortened. It was

The raw material supply pipe (21) has a check valve (22) at a portion inside the piston (10), but as shown in FIG. 8, an on-off valve (23) is used instead of the valve (22). The same effect can be obtained with the above.

Further, as shown in FIG. 9, in the case where the gas supply pipe (24) branched from the middle of the raw material supply pipe (21) is provided, after the liquid phase is discharged, the upper piston (10) is slightly elevated and at the same time the high pressure is increased. By purging the gas into the container, the residual liquid can be discharged more reliably, and the product purity is further improved.

Example 3 FIG. 10 shows a sectional view of a main part of a pressure crystallizer according to Example 3. This apparatus is a horizontal type apparatus in which the apparatus of Example 2 (FIG. 8) is provided sideways as shown in FIG. However, the product take-out pipe (14) is straight unlike the one shown in FIG.

When the above-mentioned apparatus was used to perform the same raw material supply, pressurization, solid-liquid separation, and solid-phase extraction as in Example 2, the same effects as in Example 2 were obtained.

(Effects of the Invention) According to the pressure crystallization apparatus and method of the present invention, the solid-phase extraction time can be shortened, the time required for repeated operation cycles can be shortened, and residual liquid drops on the product can be prevented. Product purity can be improved, and even if the height of the solid phase after solid-liquid separation becomes low, or even if the solid phase becomes soft or semi-solid, the solid phase extraction can be facilitated. Become.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part of a pressure crystallization apparatus according to Example 1, FIGS. 2 to 6 are diagrams showing each step of pressure crystallization according to Example 1, and FIG. 7 is related to Example 2. FIG. 8 is a sectional view of the main part of the pressure crystallizer, FIG. 8 shows a pressure crystallizer having an opening / closing valve (23) instead of the check valve (22) of FIG. 7, and FIG. ) Is a diagram showing a pressure crystallizer having a gas feed pipe (24) branched from the middle, FIG. 10 is a diagram showing a horizontal type device in which the device shown in FIG. 8 is provided horizontally, and FIG. 11 is a pressure crystal. FIG. 12 is a diagram showing a typical example of a conventional apparatus used in the crystallization method, and FIG. 12 is a diagram showing a situation when a crystallized product obtained by the conventional apparatus is taken out. (1) (11) ...... Pressure-proof cylinder, (2) ...... Cylindrical filter (3) ...... Lid, (4) ...... Piston (5) ...... Raw material supply pipe, (6) ...... Drainage passage (7) …… Pusher, (8) …… Chute (9) (16) …… Cylinder, (10) …… Upper piston (12) …… Cylindrical filter, (13) …… Ejection hole ( 14) …… Product ejection pipe, (15) …… Lower piston (16) …… Hydraulic cylinder, (17) …… Raw material supply pipe (18) …… Heating heater, (19) …… Filter (20) ) Drainage passage, (21) …… Raw material supply pipe (22) …… Check valve, (23) …… Open / close valve (24) …… Gas supply pipe, V ₁ …… Liquid supply valve V ₂ …. … Drainage valve, C… cake

Claims (2)

[Claims] 1. A pressure-resistant cylindrical body, a first piston that advances and retracts in the cylindrical body from one side opening of the cylindrical body, and a second piston that advances and retracts in the cylindrical body from the other side opening of the cylindrical body. A pressure crystallizer having a filter for discharging a liquid phase component inside the cylinder and / or on the piston pressing surface, wherein the pressure-resistant cylinder has a solid phase component penetrating the cylinder wall. A pressure crystallizer characterized in that a take-out hole is provided. 2. A container is formed by inserting a first piston and / or a second piston into a pressure resistant cylinder, and a raw material is supplied to the container and pressurized to form a mixture in a solid-liquid coexisting state. A pressure crystallization method in which a liquid phase component is discharged to the outside of a container under pressure and solid-liquid separation is performed, and then a solid phase component is extracted to the outside of the container,
A pressure crystal characterized in that the solid phase component is taken out by moving it to the solid phase part extraction hole of the pressure resistant cylinder by the first piston and the second piston and pushing it out from the hole. Analysis method.