JP2013027360A - Extractor and extraction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable to perforate cell walls and cell membranes with simple treatment, and thereby to efficiently extract products from algae within a short time.SOLUTION: There is provided an extractor 100 for extracting from algae products produced by the algae, which comprises a container vessel 110 receiving an algae liquid X1 of a culture solution containing the algae and equipped with at least a pair of electrodes 110a and 110b, a voltage applying part 130 forming a pulse electric field in the algae liquid X1 by applying a pulse voltage on the pair of the electrodes 110a and 110b, and an extraction part 150 extracting products from an algae liquid X2 after applied with the pulse voltage by using the voltage applying part 130.

Description

  The present invention relates to an extraction apparatus and an extraction method for extracting a product from algae.

  In recent years, algae (particularly microalgae) that can produce biofuels (hydrocarbons and biodiesel) and physiologically active substances such as astaxanthin have attracted attention. It is being studied to use it as energy to replace it, or to use it for medicines, cosmetics, foods, and the like. Among such algae, in particular, algae belonging to the genus Botryococcus is excellent in the ability to produce hydrocarbons, and the hydrocarbon content relative to the total amount of algal bodies is about 20 to 40% by dry weight. high.

  Conventionally, as a technique for extracting a product from an algae that produces a hydrophobic product, such as an algae of the genus Botriococcus, a wet alga body is separated by filtering a culture solution containing algae, and the wet algae After the body is lyophilized or heated and dried, the organic solvent is immersed in an organic solvent such as n-hexane or methanol-chloroform (1: 1). A technique in which the product is dissolved and extracted.

  However, in such a technique, it is necessary to dry the wet algal bodies, so that a long time is required for extraction, and energy consumption such as electric power is required for drying.

  Therefore, a technique for directly extracting a product from a wet algal body using an organic solvent of any of ethyl acetate, butyl acetate, diethyl ether, methyl-t-butyl ether, methyl ethyl ketone, and isopropyl alcohol without a drying step is disclosed. (For example, Patent Document 1).

Japanese Patent Application Laid-Open No. 09-803

  Since many of the products produced by the algae described above are retained in the algal bodies (cells), when extracting the products from the algal bodies, it is necessary to destroy the cell walls and cell membranes that make up the algal bodies.

  In the technique of Patent Document 1 described above, in order to destroy the cell wall and the cell membrane, a large amount of organic solvent such as several tens of times that of wet algal bodies is required, and when an attempt is made to improve extraction efficiency, the extraction time is also about 24 hours. It will take a long time.

  Therefore, in view of such problems, the present invention can extract pores in cell walls and cell membranes with an easy treatment, and thereby extractors and extraction methods that can efficiently extract products from algae in a short time The purpose is to provide.

  In order to solve the above problems, an extraction apparatus of the present invention is an extraction apparatus for extracting a product produced by the algae from algae, containing an algal liquid that is a culture solution containing algae, and at least one pair. A storage tank in which the electrodes are provided, a voltage application unit that forms a pulsed electric field in the algal liquid by applying a pulse voltage to the pair of electrodes, and the algal liquid after the pulse voltage is applied by the voltage application unit And an extraction unit for extracting a product from the above.

  The temperature of the algal liquid after the pulse voltage is applied by the voltage application unit may be 80 ° C. or higher and 100 ° C. or lower.

  The extraction device may further include a preheating unit that preheats the algal liquid before the pulse voltage is applied by the voltage application unit.

  The said extraction part may extract a product by pressure-filtering the algal liquid after a pulse voltage is applied by the voltage application part.

  The extraction device may further include a circulation unit that causes the algal liquid to flow so that the algal liquid stored in the storage tank circulates between the pair of electrodes.

  In order to solve the above problems, the extraction method of the present invention is an extraction method for extracting a product produced by the algae from the algae, the step of preheating the algae liquid that is a culture solution containing algae, and the preheating. The preheating step includes a step of applying a pulse voltage to the algal liquid and a step of extracting a product from the algal liquid after the pulse voltage is applied, and the temperature of the algal liquid after the pulse voltage is applied is 80 The algal liquid is preheated so as to be at least 100 ° C. and not more than 100 ° C.

  According to the present invention, it is possible to open a cell wall and a cell membrane with an easy treatment, and thereby it is possible to efficiently extract a product from algae in a short time.

It is explanatory drawing for demonstrating an extracting device. It is explanatory drawing for demonstrating an example of a voltage application part and an electrode. It is a flowchart for demonstrating the flow of a process of an extraction method.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

(Extractor 100)
FIG. 1 is an explanatory diagram for explaining an extraction device 100 according to the present embodiment. As illustrated in FIG. 1, the extraction device 100 includes a storage tank 110, a preheating unit 120, a voltage application unit 130, a circulation unit 140, and an extraction unit 150.

  The storage tank 110 communicates with the introduction pipe 112 and contains a culture solution containing algae (hereinafter referred to as algae solution) X1 introduced through the introduction pipe 112 and the valve 112a, and a pair of electrodes 110a, 110b is provided in contact with the algal liquid. Here, the algal liquid X1 introduced into the storage tank 110 is an algal liquid in a state of being cultured in a culture tank (not shown) (for example, the algae in the culture liquid is about 0.2% by weight). Alternatively, it may be an algae solution in which the algae in the culture solution is concentrated to about 1 to 15% by weight by centrifuging after culturing in a culture tank.

  The preheating unit 120 is composed of a heater or the like, and the temperature of the algal liquid X1 passing through the introduction pipe 112 is 80 ° C. or higher and 100 ° C. after the pulse voltage is applied by the voltage applying unit 130 described later. The algal liquid is preheated to a predetermined temperature so that Here, the predetermined temperature is applied with heat generated based on the pulsed electric field formed in the algal liquid by the voltage application unit 130, and as a result, the temperature of the algal liquid stored in the storage tank 110 is 80 ° C. or higher and 100 ° C. It is set to be below ℃. In the present embodiment, the predetermined temperature is, for example, 25 ° C. or more and 50 ° C. or less. Here, an example in which the actual algal liquid temperature is around 50 ° C. with 50 ° C. as a target value will be described.

  It has been reported in “Elsevier, Applied Energy 87, 2010: 2420-2423” that the extraction efficiency of hydrocarbons from algae is significantly improved when the temperature of the algal liquid is 80 ° C. or higher and 100 ° C. or lower. Accordingly, the hydrocarbons produced by the algae by the configuration in which the preheating unit 120 preheats the algal liquid X1 so that the temperature of the algal liquid after the pulse voltage is applied by the voltage application unit 130 is 80 ° C. or higher and 100 ° C. or lower. Thus, it is possible to improve the extraction efficiency of hydrocarbons from algae.

  The voltage application unit 130 forms a pulse electric field in the algal liquid X1 by applying a pulse voltage to the electrodes 110a and 110b provided in the storage tank 110. Here, the voltage application unit 130 sets the pulse width of the pulse voltage applied to the electrodes 110a and 110b to less than 100 nsec, and the electric field strength of the pulse electric field formed in the algal liquid X1 by the electrodes 110a and 110b is 30 to 300 kV / cm. A pulse voltage is applied to the electrodes 110a and 110b so that

  FIG. 2 is an explanatory diagram for explaining an example of the voltage application unit 130 and the electrodes 110a and 110b. FIG. 2A shows an example of the voltage application unit 130, and FIG. 2B shows an example of the electrodes 110a and 110b. An example is shown.

  In the example shown in FIG. 2A, the voltage application unit 130 includes a direct current power supply unit 132 that temporarily converts alternating current (for example, AC three-phase 200 V) into direct current (for example, DC 18 kV), and waveform shaping that functions as a pulse shaping circuit. Unit (B-PFN circuit) 134, a switch unit 136 configured by a gap switch, and a pulse transformer 138. Here, the waveform shaping unit 134 adjusts the pulse waveform so that the pulse width of the pulse voltage applied to the electrodes 110a and 110b is less than 100 nsec, and the DC power supply unit 132 and the pulse transformer 138 are driven by the electrodes 110a and 110b. A pulse voltage is applied to the electrodes 110a and 110b so that the electric field strength of the pulse electric field formed in the algal liquid X1 is 30 to 300 kV / cm (for example, 80 kV / cm).

  In the example shown in FIG. 2B, the electrodes 110a and 110b have a planar portion formed in a mesh shape (net-like) so that the algal fluid X1 can easily pass through, and the planar portion passes through the algal fluid X1. It is provided in the storage tank 110 so as to be orthogonal to the direction (indicated by a white arrow in FIG. 2B). Thus, by forming the electrodes 110a and 110b in a mesh shape, a pulsed electric field can be formed in the algal liquid X1 while allowing the algal liquid X1 to pass through.

  In the passage direction of the algae liquid X1, a plurality of needle-like portions 110c extending in the downstream direction are formed on the electrode 110a located on the upstream side. As a result, it is possible to apply a pulse voltage by low energy discharge (streamer discharge).

  Thus, when the voltage application unit 130 applies a pulse voltage to the electrodes 110a and 110b, a pulsed electric field can be formed in the algal liquid X1 stored in the storage tank 110, thereby forming an algal alga body. It becomes possible to make holes in the cell wall and the cell membrane. Therefore, it becomes possible to easily take out products such as hydrocarbons retained in the alga bodies (cells) to the outside through the formed holes.

  Further, the inventors of the present application set the rise time of the pulse voltage applied to the electrodes 110a and 110b by the voltage application unit 130 to 100 psec to less than 20 nsec, the pulse width to less than 100 nsec, and the fall time to 100 psec to 100 nsec or less. Furthermore, when the pulse voltage is applied to the electrodes 110a and 110b so that the electric field strength of the pulse electric field formed in the storage tank 110 (in the algal liquid X1) is 30 to 300 kV / cm, the algaecidal efficiency is high. Have found. Therefore, the voltage application unit 130 sets the pulse width of the pulse voltage to less than 100 nsec, and the electrodes 110a and 110b so that the electric field strength of the pulse electric field formed in the algal liquid X1 by the electrodes 110a and 110b is 30 to 300 kV / cm. By applying a pulse voltage to the cell wall, holes can be efficiently formed in the cell wall and cell membrane constituting the algal alga body.

  Even when the rise time of the pulse voltage is 100 psec to less than 20 nsec, the pulse width is less than 100 nsec, and the fall time is 100 psec to 100 nsec or less, depending on the characteristics of the algae, the conductivity of the culture solution, etc. When the electric field strength of the pulse electric field formed in the algal liquid X1 does not become 30 to 300 kV / cm, the number of pulse repetitions (Pulse / sec) may be increased.

  Furthermore, as described above, the algal liquid X1 is preheated to a predetermined temperature by the preheating unit 120, and is heated to 80 ° C. or more and 100 ° C. or less by applying a pulse electric field in the storage tank 110. Thus, the fluidity of the hydrocarbons produced by the algae is obtained by setting the temperature of the algal liquid X1 stored in the storage tank 110 by the preheating unit 120 and the voltage applying unit 130 as a result of 80 ° C. or more and 100 ° C. or less. It becomes possible to improve. Therefore, it is possible to improve the efficiency of taking out the hydrocarbons retained in the alga bodies to the outside through the holes formed in the cell walls and the cell membrane.

  Referring back to FIG. 1, the circulation unit 140 includes a circulation pipe 142, a valve 142a, and a pump 142b, and the algae solution X1 accommodated in the accommodation tank 110 is circulated between the electrodes 110a and 110b. Liquid X1 is allowed to flow. More specifically, the circulation pipe 142 extends from a wall surface facing the wall surface to which the introduction pipe 112 in the storage tank 110 communicates, and communicates with the introduction pipe 112. The algal liquid X1 introduced into the storage tank 110 through the introduction pipe 112 passes through between the electrodes 110a and 110b, is then pumped up by the pump 142b through the valve 142a, and is returned to the introduction pipe 112 through the circulation pipe 142 again. .

  Thereby, it is possible to continuously distribute the algal liquid X1 between the electrodes 110a and 110b, and it is possible to efficiently and evenly open holes in each of the plurality of algae included in the algal liquid X1.

  Here, the circulation unit 140 may return the algal liquid X1 that has passed between the electrodes 110a and 110b upstream from the preheating unit 120 of the introduction pipe 112. Thereby, since all the algal liquid X1 accommodated in the storage tank 110 will pass the preheating part 120, 80 degreeC which can improve the fluidity | liquidity of the hydrocarbon which is a product at the temperature of algal liquid X1. The temperature can be maintained at 100 ° C. or lower.

  The extraction unit 150 communicates with the storage tank 110 through the delivery pipe 152. More specifically, the delivery pipe 152 communicates with a wall surface opposite to the wall surface with which the introduction pipe 112 in the storage tank 110 communicates, and the algal liquid X2 after the pulse voltage is applied by the voltage application unit 130 is delivered. It is sent to the extraction unit 150 through the tube 152 and the valve 152a.

  Note that the circulation of the algal liquid X1 by the circulation unit 140 and the delivery of the algal liquid X2 from the storage tank 110 to the extraction unit 150 by the delivery pipe 152 may be performed exclusively or in parallel. For example, after the algal liquid X1 is circulated for a predetermined time by the circulation unit 140, the delivery pipe 152 may send the algal liquid X2 from the storage tank 110 to the extraction unit 150. Further, the circulation of the algal liquid X1 by the circulation unit 140 and the delivery of the algal liquid X2 from the storage tank 110 to the extraction unit 150 by the delivery pipe 152 may be performed at a predetermined flow rate.

  And the extraction part 150 extracts a product from the algae liquid X2 after a pulse voltage is applied by the voltage application part 130. FIG. Specifically, the extraction unit 150 includes, for example, a pressure filter, filters the algal liquid X2, and separates it into a filtrate (culture liquid) and a wet algal body (hydrated alga body), By pressing (pressing) the separated wet algal bodies with a roller or the like, the product retained in the algal bodies is pushed out (extracted) through the holes. Thereby, it becomes possible to extract a product (hydrocarbon) from algae without using an organic solvent.

  Alternatively, the wet algal bodies after pressurization may be immersed in an organic solvent (for example, n-hexane or a mixed solution of methanol and chloroform) to extract products remaining in the algal bodies. Even in this case, since the pores are already opened in the cell wall and cell membrane constituting the alga body, an extremely small amount of the organic solvent is compared with the case where the alga body is immersed in the organic solvent without applying a pulse voltage. Thus, the product can be extracted efficiently.

  As described above, according to the extraction apparatus 100 according to the present embodiment, holes are formed in the cell wall and cell membrane of the algal body by an easy process such as forming a pulsed electric field in the algal liquid X1 by the voltage application unit 130. Through this hole, the product can be easily extracted from the alga body to the outside. Therefore, it becomes possible to extract a product from algae efficiently in a short time.

(Extraction method)
Then, the extraction method which extracts a product from algae using the extraction apparatus 100 mentioned above is demonstrated. FIG. 3 is a flowchart for explaining the processing flow of the extraction method according to the present embodiment. In the extraction method according to the present embodiment, when a stop instruction is issued by the user, the process being performed at that time is stopped. In addition, the extraction method may introduce the algal liquid X1 from the algal liquid source such as the culture tank to the storage tank 110 after completion of all the following steps (steps, processing), or the algae such as the culture tank. By introducing the algal liquid X1 sequentially or continuously from the liquid source to the storage tank 110, the respective steps may be performed in parallel and continuously.

  First, the control device (not shown) keeps the valves 112a, 142a, and 152a closed and the pump 142b off.

  As shown in FIG. 3, when the user tries to extract a product from algae, the control device opens the valve 112a (S200). Then, the algal liquid X1 is supplied to the introduction pipe 112 from an unillustrated algal liquid source.

  Subsequently, the preheating unit 120 turns on the heater to preheat the algal liquid X1 flowing through the introduction pipe 112 to a predetermined temperature (for example, around 50 ° C.) (S202), and the algal liquid preheated to the predetermined temperature. X1 is introduced into the storage tank 110 through the introduction pipe 112 (S204). When the algal liquid X1 introduced into the storage tank 110 reaches a predetermined amount (the degree to which the electrodes 110a and 110b are immersed in the algal liquid X1) (YES in S206), the control device closes the valve 112a. The introduction of the algal liquid X1 is terminated (S208).

  Next, the voltage application unit 130 starts application of a pulse voltage to the electrodes 110a and 110b to form a pulse electric field in the algal liquid X1 (S210), and the control device controls the valve 142a of the circulation unit 140. In the open state, the pump 142b is turned on, and the algal liquid X1 in the storage tank 110 is returned again to the introduction pipe 112 through the circulation pipe 142 (S212). Here, the circulation pipe 142 returns the algal liquid X1 downstream of the valve 112 a in the introduction pipe 112 and upstream of the preheating unit 120 of the introduction pipe 112.

  Then, until a predetermined time elapses (NO in S214), the voltage application unit 130 applies a pulse voltage to the electrodes 110a and 110b, and the circulation unit 140 circulates the algal liquid X1, and when a predetermined time elapses (YES in S214) The voltage application unit 130 ends the application of the pulse voltage to the electrodes 110a and 110b (S216). Further, the control device closes the valve 142a of the circulation unit 140, turns off the pump 142b, and ends the circulation of the algal liquid X1 by the circulation unit 140.

  Subsequently, the control device opens the valve 152a. Then, the algal liquid X2 after the pulse voltage is applied by the voltage application unit 130 is sent out from the storage tank 110 to the extraction unit 150 through the delivery pipe 152 and the valve 152a (S218). And the extraction part 150 extracts a product from the algal liquid X2 (S220).

  As described above, even with the extraction method described above, it is possible to make holes in the cell walls and cell membranes of algal bodies by an easy process such as forming a pulsed electric field in the algal liquid X1 by the voltage application unit 130. Therefore, the product can be easily extracted from the alga body to the outside through the pores by pressure filtration or the like. Thereby, it becomes possible to extract a product from algae efficiently in a short time.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  For example, in the above-described embodiment, the example in which the preheating unit 120 is configured by a heater or the like has been described. However, the preheating unit 120 only needs to be able to preheat the algal liquid X1 to a predetermined temperature, and is generated in a power plant such as a thermal power plant or a manufacturing plant. Waste heat may be used. With the configuration in which the preheating unit 120 uses exhaust heat, power consumption can be reduced, and the cost for extracting the product from the algae can be reduced.

  Further, in the above-described embodiment, the configuration of the voltage application unit 130 described with reference to FIG. 2 is an example, and the cell walls and the cell membranes constituting the algal algal body are applied regardless of the application of the pulse voltage by the streamer discharge. As long as it is possible to form a pulse electric field that can open a hole, the pulse voltage may be applied in any discharge mode.

  Furthermore, in the above-described embodiment, the configuration in which the electrode 110a includes the needle-like portion 110c has been described. However, the electrode 110b may include a plurality of needle-like portions extending in the upstream direction, or both of the electrodes 110a and 110b. May be provided with a needle-like portion.

  In the above-described embodiment, the configuration in which the storage tank 110 is provided with the pair of electrodes 110a and 110b has been described, but the number of electrodes is not limited and may be two or more.

  Furthermore, in the above-described embodiment, the case where the extraction unit 150 is a pressure filter has been described as an example. However, the extraction unit filters the algal liquid X2 and organically obtains the wet alga body as it is. The product retained in the algal bodies may be extracted by immersing in a solvent (for example, n-hexane or a mixed solution of methanol and chloroform). Even in this case, since the pores are already opened in the cell wall and cell membrane constituting the alga body, about 1/10 compared with the case where the alga body is directly immersed in an organic solvent without applying a pulse voltage. The product can be efficiently extracted with a small amount of organic solvent.

  Moreover, although the structure provided with the preheating part 120 was demonstrated in embodiment mentioned above, the algal liquid X1 should just become 80 degreeC or more and 100 degrees C or less as a result in the storage tank 110, and even if it does not provide the preheating part 120, voltage application The temperature of the algal liquid X1 can be set to 80 ° C. or more and 100 ° C. or less by extending the time for applying the pulse voltage by the unit 130 or increasing the voltage value.

  Further, in the above-described embodiment, the example in which the circulation unit 140 includes the circulation pipe 142, the valve 142a, and the pump 142b has been described. However, the algal liquid X1 stored in the storage tank 110 is between the electrodes 110a and 110b. For example, the circulation unit 140 may be configured by a stirrer, a mixer, or the like for stirring the algae solution X1 in the storage tank 110.

  Moreover, although the structure provided with the circulation part 140 was demonstrated in embodiment mentioned above, what is necessary is just to be able to open a hole uniformly in each of the several algae contained in the algal liquid X1 accommodated in the storage tank 110, and the circulation part 140 is provided. As a matter of course, the time for applying the pulse voltage by the voltage application unit 130 may be lengthened so that holes are evenly opened in the plurality of algae contained in the algae liquid X1.

  Further, the extraction device 100 may be provided with a valve or a pump other than the positions shown in FIG.

  It should be noted that each step of the extraction method of the present specification does not necessarily have to be processed in time series in the order described in the flowchart, and may include parallel or subroutine processing.

  INDUSTRIAL APPLICATION This invention can be utilized for the extraction apparatus and extraction method which extract a product from algae.

X1, X2 ... Algae solution 100 ... Extraction device 110 ... Storage tank 110a, 110b ... Electrode 120 ... Preheating part 130 ... Voltage application part 140 ... Circulation part 150 ... Extraction part

Claims (6)

An extraction device for extracting a product produced by the algae from the algae,
Containing algae liquid, which is a culture solution containing algae, and a storage tank provided with at least one pair of electrodes;
A voltage applying unit that forms a pulsed electric field in the algal liquid by applying a pulse voltage to the pair of electrodes;
An extraction unit for extracting the product from the algae liquid after a pulse voltage is applied by the voltage application unit;
An extraction device comprising:   The extraction device according to claim 1, wherein the temperature of the algal liquid after the pulse voltage is applied by the voltage application unit is 80 ° C. or more and 100 ° C. or less.   The extraction device according to claim 1, further comprising a preheating unit that preheats the algal liquid before a pulse voltage is applied by the voltage application unit.   The said extraction part extracts the said product by carrying out pressure filtration of the algal liquid after the pulse voltage is applied by the said voltage application part, It is any one of Claim 1 to 3 characterized by the above-mentioned. Extraction device.   5. The circulation unit according to claim 1, further comprising a circulation unit configured to flow the algal liquid so that the algal liquid stored in the storage tank circulates between the pair of electrodes. Extraction device. An extraction method for extracting a product produced by the algae from the algae,
A step of preheating an algae solution that is a culture solution containing algae;
Applying a pulse voltage to the preheated algal liquid;
Extracting the product from the algal fluid after applying the pulse voltage;
Including
The preheating step includes preheating the algal liquid so that the temperature of the algal liquid after applying the pulse voltage is 80 ° C. or higher and 100 ° C. or lower.

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