JP3010099B2 - Supercritical fluid extraction device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an extraction device for extracting a useful component using a supercritical fluid.

[0002]

2. Description of the Related Art A conventional extraction apparatus using liquefied carbon dioxide gas is known from Japanese Patent Publication No. 54-3940. This extraction device is for effectively extracting animal and plant substances, and is superior in the following points as compared with conventional extraction with an organic solvent by using liquefied carbon dioxide gas. That is, a purification step for removing the residual solvent contained in the extract is not required (the residual solvent often becomes a problem in foods).

[0003] The extraction accuracy is high.

[0004] The extraction time is reduced.

[0005] The extract does not add toxicity.

It is safe and economical to handle.

In the above publication, liquefied carbon dioxide gas is used as the extraction solvent. However, in order to perform extraction and separation more efficiently in consideration of the diffusion coefficient and solubility of the extract, supercritical carbon dioxide is used. Use of gas can be considered, and such a method can be exemplified by the extraction separation method disclosed in JP-A-61-204002. This method comprises: an extraction step of dissolving and extracting a predetermined component from a substance to be extracted; a separation step of separating a specific component from the component extracted in the extraction step; a pressurization step of pressurizing the solvent; A heating step of heating the solvent alone or together with the substance to be extracted to a temperature above the critical point of the solvent to obtain a solvent in a supercritical state, and performing the extraction with the solvent in the supercritical state obtained in the heating step. It is configured to be extracted in the process. In this extraction method, a filter is used to remove impurities in the solvent, and in the embodiment, only one separator is employed. No mention is made of the removal of trace odor components or moisture in the solvent.

FIG. 2 shows a conventional supercritical fluid (carbon dioxide).
FIG. 4 is an explanatory diagram for describing a general extraction device and a method using the method. As shown in this figure, a supercritical fluid extraction device (hereinafter simply referred to as an extraction device 1) has a carbon dioxide storage tank 2 for storing liquid carbon dioxide as an extraction solvent, and a carbon dioxide storage tank derived from the carbon dioxide storage tank 2. Carbon (solvent)
A first heat exchanger 31 for further cooling the solvent by heat exchange with a refrigerant, a compression pump 4 for compressing the derived solvent, and a second heat exchanger for controlling the solvent to a predetermined temperature by heat exchange with a heat medium such as hot water. A two-heat exchanger 32, an extractor 5 for extracting an extracted component from the raw material M with a solvent filled with the raw material M and supplied from the bottom, and a solvent derived from the extractor 5 for heating steam or the like. A third heat exchanger 33 for heating by heat exchange, and a separator 6 for separating and recovering the extracted components in the solvent
And a condenser 7 for cooling the solvent after the extraction component separation by heat exchange with a refrigerant, and these are connected in series and annularly by one pipe.

A flow meter 41 is provided between the compression pump 4 and the second heat exchanger 32, and a first pressure regulating valve 5a is provided between the extractor 5 and the third heat exchanger 33. A second pressure regulating valve 6a and a filter 6b for removing impurities in the solvent are provided between the separator 6 and the condenser 7.

[0010] In such an extraction apparatus 1, the solvent led out of the compression pump 4 is brought into a supercritical state, and
In the above, the raw material M filled in the basket 51 flows through, while the extracted components in the raw material M are effectively extracted by the solvent in the supercritical state.

The separation and recovery of the extracted components from the solvent is performed by a separator 6
The separation conditions include the separation temperature performed by adjusting the third heat exchanger 33 on the outlet side of the extractor 5 and the opening degrees of the first pressure regulating valve 5a and the second pressure regulating valve 6a. There are two conditions, that is, the separation pressure performed by adjusting the pressure, and by setting these conditions, the actual separation and recovery of the extracted components is performed.

[0012]

By the way, in the conventional extraction device 1 as shown in FIG. 2, only one separator 6 is provided in the system, so that the extraction component is separated from the solvent. Conditions for separation (separation temperature and pressure)
Can set only one point.

However, the raw material M usually contains a plurality of types of extracted components, and the conditions for separating the plurality of types of components are generally different from each other. Nevertheless, conventionally, since only one separation condition can be set, there is a disadvantage that other useful components having different separation conditions are missed.

In addition, components that could not be separated in the separator 6 may be removed by a filter 6b provided downstream of the separator 6, but there is a limit to this, and the solvent is removed for a long time. If the solvent is used in a circulating manner, impurities are mixed in the solvent and the purity is reduced, so that there is a problem that the extraction efficiency in the extractor 5 is reduced and the quality of the extract is reduced.

Further, if only one separator 6 is provided, the water in the solvent cannot be sufficiently removed, and as a result, a solid which is a hydrate of carbon dioxide and water before the compression pump 4 can be obtained. Hydrate is generated, which causes a blockage of the piping.

As described above, in the conventional extraction apparatus, the solvent used in circulation is greatly deteriorated, and various inconveniences have occurred due to insufficient purification treatment.

An improved version of such an extraction device 1 is disclosed in Japanese Patent Application Laid-Open No. Hei 3-21302. The apparatus disclosed in this publication is configured such that a plurality of separators are provided in parallel, pressure and temperature conditions are changed, and a plurality of extracted components are separated according to a difference in solubility. However, in the case of this apparatus, the purpose is to efficiently separate and recover the extract, and the quality when the raffinate is a product and the deterioration of carbon dioxide as a solvent are not taken into account. Concerns remain about stable operation of the extraction device.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems.
Provided is a supercritical fluid extraction device that can efficiently separate and recover extracted components, improve product quality, and operate the extraction device smoothly without trouble due to clogging of piping. It is intended to be.

[0019]

A supercritical fluid extracting apparatus according to the present invention comprises a supercritical fluid producing means for producing a supercritical fluid solvent by condensing, cooling and compressing carbon dioxide ; In a supercritical fluid extraction apparatus comprising: an extraction means for extracting an extraction component in a raw material by the supercritical fluidized solvent, and a separation means for separating and recovering the extraction component extracted in the solvent, the supercritical fluid The production means is provided with a condenser and a compression pump for producing a supercritical fluidized solvent, and the extraction component in the filled raw material is extracted by the supercritical fluidized solvent. An extractor is provided, and a plurality of separators for separating the vaporized solvent and the other are arranged in series in the separation means, and an upstream side of the extractor serves as an entrainer.
A water supply device for supplying water to the extractor is provided, and
The separator is derived from the extraction means, and after decompression.
A first separator for separating the extracted components from the heated solvent,
Solvent derived from this first separator and cooled
Extract components not separated and recovered by the first separator
A second separator and a solvent derived from the second separator.
Adsorption removal of one or both of residual components and moisture
And a separator to be removed .

[0020]

According to the supercritical fluid extraction device of the present invention, the separation means for separating the extracted component from the solvent introduced by the extraction means is provided with a plurality of separators in series. The separation means can more reliably separate and collect the extracted components, and can also separate and remove water as an impurity and organic components that could not be separated from the solvent, resulting in a reduced yield of the extracted components. As it rises, the solvent in a clean state will be circulated and used, stabilizing the operating state, such as preventing pipe clogging,
Further, the quality of the extracted component is improved.

[0021] Then, among the plurality of separators, the first major extractives separation and recovery of the solvent in the first separator, not separated in the first separator, such as with water in a second separator the following extraction The components are separated and recovered.

Also, a component provided downstream of the second separator is provided.
Since a very small amount of residue and water remaining in the solvent are removed in the separator, the solvent becomes clean with almost completely removed impurities.

[0023]

FIG. 1 is an explanatory diagram showing the configuration of a supercritical fluid extraction device according to the present invention. As shown in this figure, in the present embodiment, the extraction device 1 is a supercritical fluid producing apparatus that supercools and compresses a liquid solvent supplied from a solvent storage tank to convert the solvent into a supercritical fluid. Means 1a, extraction means 1b provided with an extractor for extracting an extraction component in the raw material filled with the supercritical fluidized solvent supplied from the supercritical fluid producing means 1a, and extraction in the solvent. And a separating means 1c having a separator for separating and collecting the extracted components.

In this embodiment, carbon dioxide is used as a solvent for extracting an extraction component from the raw material.

The supercritical fluid producing means 1a includes a separating means 1
a condenser 7 which liquefies carbon dioxide as a solvent at a substantially normal temperature circulated and supplied from c with heat exchange with a refrigerant such as cold water;
A first carbon dioxide storage tank 2 for temporarily storing carbon dioxide liquefied by the condenser 7 and a first supercooling the liquid carbon dioxide storage tank 2 derived from the carbon dioxide storage tank 2 to a lower temperature by heat exchange with a refrigerant. The heat exchanger 31 includes a heat exchanger 31 and a compression pump 4 provided downstream of the first heat exchanger 31. A flow meter 41 is provided upstream of the compression pump 4 so that the amount of carbon dioxide supplied by the compression pump 4 can be measured.

In the supercritical fluid producing means 1a,
Carbon dioxide as a solvent is in a liquid state. And
The pressure of the carbon dioxide discharged from the carbon dioxide storage tank 2 reaches a critical value or more by the compression by the compression pump 4 after the cooling by the first heat exchanger 31.

The extraction means 1b is provided with a second heat exchanger for heating carbon dioxide near the critical value fed from the upstream compression pump 4 into a so-called supercritical fluid exceeding the critical temperature and critical pressure. 32, and an extractor 5 that receives the supply of the supercritical fluid derived from the second heat exchanger 32 and extracts an extraction component from the loaded raw material.

A basket 51 made of a metal mesh is provided inside the extractor 5, and the raw material is put in the basket 51, and the basket 51 containing the raw material is extracted. The raw material is charged into the extractor 5 by being charged into the extractor 5. The supercritical carbon dioxide introduced from the bottom of the extractor 5 immerses the raw material sequentially from the lower part in the basket 51 toward the upper part, during which the extracted components in the raw material are dissolved. Transfer into carbon dioxide.

In this embodiment, water serving as an entrainer (carrier) for efficiently extracting extracted components is provided in a pipe connecting between the second heat exchanger 32 and the extractor 5. 42. Further, on the outlet side of the extractor 5, a first pressure regulating valve 5a is provided.

The separating means 1c comprises a third heat exchanger 33 for heating a part of the carbon dioxide which is led out of the extractor 5 and decompressed and liquefied by the first pressure regulating valve 5a. The fourth heat exchanger 34 for changing the temperature condition of the carbon dioxide derived from the first separator 61
And a second separator 62 that separates the extracted components and water that have not been separated and recovered by the first separator, and the first and second separators 61 and 62 from the carbon dioxide derived from the second separator 62. And a fourth separator 64 for removing water from the carbon dioxide derived from the third separator 63. In the separation means 1c, carbon dioxide as a solvent is converted into a gaseous state and subjected to various treatments.

Heating steam is supplied to the third heat exchanger 33 as a heat exchange heat source for heating. The heating steam and the low-temperature carbon dioxide extracted from the raw material and extracted from the extractor 5 And carbon dioxide is heated to a predetermined temperature and completely gasified and supplied to the first separator 61.

The first separator 61 is a main separator in the separation means 1c, and separates gaseous carbon dioxide and a liquid extraction component. In order to perform this separation well, the pressure in the first separator 61 is 40 kg / cm2 to 74 kg / cm2, preferably 50 kg / cm2.
７０70 kg / cm 2, and the temperature is controlled between 30 ° C. and 80 ° C. Then, the optimum temperature and pressure for each extracted component obtained by experiments within the above range are employed during the actual operation.

The above pressure and temperature conditions are employed for the following reasons. That is, in general, the solubility of a gas (in the case of this embodiment, gaseous carbon dioxide) with respect to the extracted component is lower as the gas pressure is lower. Therefore, the lower the pressure, the more carbon dioxide from the extracted component. It is convenient to get out. However, the lower the pressure is, the lower the saturation temperature of the carbon dioxide is. Accordingly, unless the temperature is lowered, the carbon dioxide used in circulation cannot be stored in the carbon dioxide storage tank 2 in a liquid state. If the temperature is lowered, a large amount of hydrate, which is a hydrate of carbon dioxide and water, is generated in the pipes, which hinders smooth operation. In order to avoid these inconveniences, the above pressure and temperature conditions are adopted.

The pressure value is the same in the second separator 62, the third separator 63, and the fourth separator 64 described below. The same applies to the gas pressure in the storage tank 2.

The second separator 62 is a separator for separating extracted components and water that could not be separated by the first separator 61. The separated water contains the extracted components. Therefore, the extracted component can be further recovered by separately purifying this water.

The temperature condition of the second separator 62 is 20 ° C.
To 45 ° C, preferably 20 ° C to 35 ° C. This temperature is realized by controlling the fourth heat exchanger 34 that cools the carbon dioxide discharged from the first separator 61 by performing heat exchange with cold water. The reason why the above temperature conditions are set is that the temperature is lower than that of the first separator, thereby separating and recovering the extracted components that could not be separated by the first separator, particularly the hydrophilic substance and water. For,
In addition, under the above pressure conditions, the second separator 62 is heated to about 5 ° C. higher than its saturation temperature so as not to liquefy carbon dioxide.
This is because I want to set the temperature inside.

The same temperature conditions are applied to the third and fourth separators 63 and 64. In addition,
The temperature of carbon dioxide may be set according to the operating conditions of these separators 63 and 64.

The third separator 63 is for removing residual substances that could not be separated and recovered by the first and second separators 61 and 62. A typical example of this residual substance is a vapor of an extracted component mixed with gaseous carbon dioxide. In addition, organic components as impurities can also be mentioned. The third separator 63 is a so-called activated carbon adsorption tower, and the residual substances are adsorbed and removed by granular activated carbon filled in the third separator 63. As an adsorbent for adsorbing and removing the residue, activated alumina, zeolite, and the like can be used in addition to activated carbon.
When the object to be adsorbed is almost an organic component as in the extraction device of the present embodiment, activated carbon is most suitable.

The fourth separator 64 is for removing water from the carbon dioxide discharged from the third separator. The fourth separator 64 is filled with activated alumina. In addition to activated alumina, activated carbon, silica gel, synthetic zeolite, or the like can be used as a filler for removing moisture, but activated alumina is most preferred.

The gaseous carbon dioxide which has been dried and whose moisture has been removed by the fourth separator 64 is supplied to the condenser 7 of the supercritical fluid producing means 1a and is circulated for use.

Since the supercritical fluid extraction device of this embodiment is configured as described above, first, the supercritical fluid production means 1a
In, the gaseous carbon dioxide supplied from the separation means 1c in the preceding step is cooled by heat exchange in the condenser 7,
It is liquefied and temporarily stored in the carbon dioxide storage tank 2. And
The liquid carbon dioxide in the carbon dioxide storage tank 2 is appropriately extracted from the lower part thereof according to the operation of the compression pump 4, heat exchange with the refrigerant is performed in the first heat exchanger 31, and further cooled. It is pressurized and led out to the next extraction means 1b.

The liquid carbon dioxide supplied to the extraction means 1b is first heated by the second heat exchanger 32 by heat exchange with the heat medium to become a supercritical fluid, and is separately supplied from the water supply device 42 as an entrainer. It merges with the water and is introduced at the bottom of the extractor 5. Since the raw material for extraction is previously filled in the basket 51 of the extractor 5, the carbon dioxide in a supercritical state is immersed so that the raw material in the basket 51 flows from the lower part to the upper part. The extracted components inside are extracted and transferred into carbon dioxide in a supercritical state. The raw material from which the extracted components have been extracted may be a product.

The carbon dioxide almost saturated with the extracted component is supplied from the top of the extractor 5 to the third heat exchanger 33 in the separating means 1c via the first pressure regulating valve 5a, and is heated by heat exchange to 30 To 80 ° C. In this case, by appropriately controlling the first pressure regulating valve 5a, the carbon dioxide is supplied to the first separator 61 in a gaseous state having a pressure of 50 kg / cm2 to 74 kg / cm2. In the first separator 61, the extracted component is separated from the gaseous carbon dioxide and accumulates at the bottom of the first separator 61, and the stored extracted component may be appropriately extracted to be a product.

On the other hand, the gaseous carbon dioxide led out from the upper part of the first separator 61 is led out to the fourth heat exchanger 34, where it is cooled to 20 to 45 ° C. by heat exchange with cold water. , To the second separator 62. In the second separator 62, the extracted components and water that were not separated and recovered by the first separator are removed, and the extracted components that could not be separated by the first separator 61 are also separated and recovered.

Then, the carbon dioxide discharged from the second separator 62 is adsorbed and removed by the third separator 63, and the fourth separator 64 removes moisture, and becomes a dry state. It is supplied to the condenser 7 of the production means 1a and is circulated and used.

As described above, the extraction device 1 of this embodiment is
In the separating means 1c, a total of four separators, a first separator 61, a second separator 62, a third separator 63, and a fourth separator 64, are arranged in series as the separator 6, and are used in circulation. Since the extraction components, water, and other residues and residual moisture are sequentially removed from carbon dioxide as a solvent, the product yield increases, product quality improves, and carbon dioxide as a solvent is constantly cleaned. , The trouble of pipe clogging is reduced, and smooth operation of the extraction device 1 is realized.

In the above embodiment, four separators 6 are provided, but the present invention is not limited to four separators, and two or five or more separators may be used.

In the above embodiment, the first separator 61 is provided as the main separator for taking out the product, but another separator is provided upstream of the first separator 61, If a pressure regulating valve is provided between one separator 61 and the pressure regulating valve and the first pressure regulating valve 5a are operated to control the pressure in the separator to 74 kg / cm 2 or more, the extraction component can be reduced. This is applicable to a case where a plurality of types exist, which is convenient.

[0049]

As described above, the supercritical flow of the present invention
The body extraction device heats and supplies the liquid solvent supplied from the storage tank.
Supercritical flow to convert the above solvent into supercritical fluid by compression and compression
Body production means and supplied from this supercritical fluid production means
Extraction components in raw material by supercritical fluidized solvent
Extraction means provided with an extractor for extraction, and
Separation with a separator for separating and recovering the extracted components
A supercritical fluid extraction device comprising:
Separation means to separate the extracted components from the introduced solvent
Is provided with a plurality of separators.
Separation and recovery of extracted components
Water and impurities cannot be separated
Organic components can also be separated and removed from the solvent,
The resultFruitPurified solvents will be recycled.
Operating conditions, such as preventing blockage of pipingTransform
You.

Further, as the plurality of separators, a first separator for separating the extracted component from the solvent by heating the solvent derived from the extraction means after decompression , a second separator for removing extractives not separated recovered in the first separator by cooling the derived solvent, remove residual components and moisture of the solvent derived from the second separator min due to the provision of the releasing device is first major extractives separation and recovery of the solvent in the first separator, extractives of separation and recovery that was not separated in the first separator, such as with water in a second separator the following is thereby a solvent can be ones cleaning the impurities are almost completely removed
You. In particular, in the second separator, water is separated by lowering the temperature than in the first separator, and accordingly, the hydrophilic substance is separated more efficiently.

According to the present invention, as described above, a plurality of separators are provided in the separation means of the extraction apparatus to separate and recover the extracted components extracted in the solvent in a plurality of stages, and to remove impurities in the solvent. because the solvent is recycled is always clean, it can be operated smoothly and extraction device.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an example of a supercritical fluid extraction device of the present invention.

FIG. 2 is an explanatory diagram showing an example of a conventional supercritical fluid extraction device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Extraction apparatus 1a Supercritical fluid production means 1b Extraction means 1c Separation means 2 Carbon dioxide storage tank 31 First heat exchanger 32 Second heat exchanger 33 Third heat exchanger 34 Fourth heat exchanger 4 Compression pump 5 Extractor 51 Basket 6 Separator 61 First separator 62 Second separator 63 Third separator 64 Fourth separator 7 Condenser

Continuing from the front page (72) Inventor Toshio Ifu 6-2 Umegaoka, Midori-ku, Yokohama-shi, Kanagawa Prefecture Inside the Tobacco Central Research Institute, Japan Tobacco Inc. (72) Inventor Ken Kamemoto 1-77, Kurobeoka, Hiratsuka-shi, Kanagawa Japan Inside the Hiratsuka Plant of Tobacco Inc. (72) Inventor Osamu Kato 1-3-18 Wakihamacho, Chuo-ku, Kobe Kobe Steel, Ltd.Kobe Head Office (72) Inventor Masahiro Yamagata Wakihama-cho, Chuo-ku, Kobe 1-3-18 Kobe Steel, Ltd. Kobe Head Office (56) References JP-A-61-204002 (JP, A) JP-A-2-139003 (JP, A) JP-A 4-149148 (JP) , A) (58) Fields surveyed (Int. Cl. ⁷ , DB name) B01D 11/00

Claims (1)

(57) [Claims] 1. A supercritical fluid producing means for producing a supercritical fluidized solvent by condensing, cooling and compressing carbon dioxide , and an extracting means for extracting an extraction component in a raw material with the supercritical fluidized solvent. And a separating means for separating and recovering the extracted components extracted in the solvent, wherein the supercritical fluid producing means includes a condenser and a compression device for producing a supercritical fluidized solvent. A pump is provided, and the extraction means is provided with an extractor in which the extracted component in the filled raw material is extracted by the supercritical fluidized solvent, and the separation means includes a vaporized solvent and other A plurality of separators for separation are arranged in series, and water as an entrainer is provided upstream of the extractor.
A water supply device for supplying to the extractor is provided,
The vessel is derived from the extraction means and heated after decompression.
A first separator for separating the extracted components from the separated solvent,
From the first separator and from the cooled solvent
One to remove the extracted components that were not separated and recovered by one separator
Two separators and residual solvent derived from the second separator
Adsorb and remove one or both of components and water
That separator and supercritical fluid extraction apparatus characterized by being composed.