JPS63233773A - Culture device - Google Patents

Abstract

PURPOSE:To increase the concentration of organisms in a culture tank and to prevent the damage of the organisms, by inducing an ascending flow and descending flow in a culture tank by a heating means and a cooling means, respectively, and stirring the culture liquid with the flows in the culture tank. CONSTITUTION:A culture tank 10 for the culture of organisms is provided, at an arbitrary position inside or outside of the tank, with a heating means 16 to locally heat the liquid 14 contained in the culture tank 10 to cause an ascending flow and with a cooling means 18 to locally cool the liquid 14 to cause a descending flow. If necessary, the tank 10 is further provided with a partition wall 24 to effectively generate circulation flow. Furthermore, a static mixer 26 may be placed in either one of the ascending flow channel and descending flow channel to further improve the effectiveness of the agitation of the liquid 14 by generating a turbulent flow in the ascending flow or the descending flow.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a culture apparatus, particularly to improvements in stirring during biological culture.

[Prior Art] In recent years, the production of useful substances by culturing plant cells, bacteria, etc. has been attracting attention. In order to improve the productivity of these useful substances, an important issue is how to increase the concentration of organisms in the culture tank.

That is, for example, when culturing plant cells, typically about 1
This is done using a 0x culture solution. As the amount of culture solution increases, a larger culture tank is required, so it is desirable to increase the concentration of organisms as much as possible.

If the concentration of living organisms is increased, the corresponding nutrients must be supplied, and this must be supplied to all living organisms. This requires sufficient stirring.

Usually, this stirring is carried out using a stirring blade, liquid circulation using a pump, air blowing, or the like.

Problems to be solved by the invention C] Plant cells and certain types of bacteria are extremely susceptible to impact and are damaged by strong agitation.

Therefore, if agitation is performed with the necessary strength using conventional stirring means, the organisms may be damaged and the desired culture cannot be carried out. Therefore, in the end, it was not possible to increase the concentration of organisms in the culture tank very much.

This invention was made to solve these problems, and even though the liquid in the culture tank can be sufficiently stirred, the impact on organisms is very small, so it is possible to increase the concentration of organisms. The purpose is to provide a culture device.

[Means for Solving the Problems] The culture device of the present invention includes a culture tank for culturing organisms, and a liquid contained in the culture tank that locally heats it to generate an upward flow. It is characterized by comprising: a heating means; and a cooling means for locally cooling the liquid to generate a downward flow.

[Operation] A circulating flow is generated in the culture tank by an upward flow caused by the heating means and a downward flow caused by the cooling means, and stirring is thereby performed. In this stirring, no mechanical shearing force is applied to the liquid being stirred, so sufficient stirring can be performed without damaging living organisms.

[Example] Embodiments of the invention will be described based on the drawings.

FIG. 1 schematically shows an embodiment of the present invention.

A culture tank 12 of the culture device 10 contains a liquid 14 containing an organism desired to be cultured. This liquid 14 contains a culture solution about five times the amount of normal biomass, and the amount of solid matter is about several percent.

In the liquid 14 of the culture tank 12, a heating device 16 and a cooling device 1 are installed.
8 is provided. The heating device 16 is arranged at the center of the bottom of the culture tank IZ, and the cooling device 18 is arranged along the inner surface of the side wall of the culture tank 12.

Here, when this culture tank 12 is cylindrical, it is desirable to form the heating device 16 in a disk shape and the cooling device 18 in a cylindrical shape.

The heating device 16 is heated by suitable means, for example electrical means. Then, the temperature of the liquid 14 around this heating device 16 rises and moves upward.

In addition, the cooling device 18 uses a circulating refrigerant, for example.
kept at low temperature. The liquid 14 near this cooling device 18 is then cooled and moves downward.

In this way, an upward flow is generated in the liquid 14 in the culture tank 12 near the center by the heating bag v113, and a downward flow is generated in the peripheral portion by the cooling device 18. Due to the synergistic effect of these upward and downward flows, a circulating flow as shown by the arrow is generated in the liquid 14. The liquid 14 is stirred by this circulating flow.

Such agitation does not apply mechanical shearing force to 1 & 14, so that almost no impact is given to the organisms contained in liquid 14. Therefore, even when culturing organisms that are sensitive to shock, sufficient stirring can be performed with little risk of damaging the organisms, so that the concentration of the organisms can be increased. This allows the culture device 10 to be made more compact.

The stirring intensity is adjusted by adjusting the heating function of the heating device 1B and the cooling function of the cooling device 18. However, if the temperature difference between the heating device 16 and the cooling device 18 is too large, it will have an adverse effect on living things that come into contact with them, so this temperature difference is usually kept within 10 degrees, more preferably within 5 degrees.

Note that since it is easier to adjust the functions of the heating device 16, it is preferable to normally only adjust the heating device 16 and adjust the functions of the cooling device 18 when particularly necessary.

Actual culturing is usually carried out in a batch manner. That is, the liquid 14 is initially composed of a culture solution containing breeding stock and nutrients at an appropriate concentration. Then, conditions such as temperature, pH, and Do (dissolved oxygen) are set to be suitable for culturing the organism, and culturing is carried out while supplementing the nutrient solution as needed.

The reason why the nutrient solution is replenished here is that if all the necessary amount is added at the beginning, the concentration will become too high, which will have a negative effect on the culture of the organism.

Since the liquid 14 is sufficiently stirred by the stirring by the heating device 16 and the cooling device 18, nutrients are distributed to all living organisms, and effective cultivation is performed.

Further, it is preferable to detect the concentration of nutrients in the culture solution and control the replenishment of the above-mentioned nutrient solution so that the concentration is maintained at an appropriate concentration. Depending on the type of nutrient, a pH meter, ultraviolet absorbance meter, etc. are used.

Furthermore, a stirring heating device 16 and a cooling device 18 are also used to control the temperature of the liquid 14 in the culture tank 12. That is, the detection signal from the thermometer 20 is input to the controller 22. The controller 22 increases the heating function of the heating device 16 when the temperature is low, and increases the function of the cooling device 18 when the temperature is high. Alternatively, control may be performed by reducing the function of the heating device 16 or the cooling device 18.

In addition, this solid concentration in the liquid 14 of the culture tank 12 is
It is advisable to provide a densitometer such as an ultrasonic type that measures pI. liquid 14
This signal indicates the amount of biomass in the liquid 14, since the amount of biomass in the liquid is proportional to the concentration of solids.

Therefore, it is advisable to adjust the amount of nutrients supplied and the stirring intensity depending on the biomass. Alternatively, this solid matter concentration may be used as a signal for the end of culture.

Another embodiment of the invention is shown in FIGS. 2-4.

In the example shown in FIG. 2, the heating device 16 is provided on the peripheral side, and the cooling device 18 is provided near the center. As a result, a circulating flow is generated in the liquid 14 in the culture tank 12, which rises at the periphery and descends at the center, contrary to the example shown in FIG.

Further, in this example, a partition wall 24 is provided to effectively generate a circulating flow. As a result, the inside of the culture tank 12 is partitioned into an ascending passage 12a and a descending passage 12b. Therefore, the upward flow and the downward flow do not interfere with each other and weaken the circulation flow, and effective stirring can be performed.

In the example shown in FIG.
A static mixer 26 is provided within 2a. This static mixer 26 is composed of, for example, two cut screws, and creates turbulence in the rising liquid 14, thereby making the stirring of the liquid 14 more effective.

Furthermore, in this example, the heating device 16 and the cooling device 18 are
It is attached to the outer peripheral surface of the culture tank 12.

Therefore, these repairs and inspections can be carried out without regard to the inside of the culture tank 12, and it is particularly suitable for cases such as bacterial culture where contamination with germs and the like must not occur.

In the example shown in FIG. 4, the heating device 16 and the cooling device 18
The arrangement is reversed from the example shown in FIG. That is, a rising passage 12a is formed here by the heating device 16 arranged at the periphery, and a descending passage 12b is formed here by the cooling device 18 arranged at the center. Since the static mixer 26 is disposed in the descending passage 12b, stirring of the descending liquid 14 is promoted by the static mixer 26.

Note that various types of devices can be used as the heating device 16 and the cooling device 18, and a heat pump may also be used. According to the heat pump, the heat recovered by the cooling device 8 can be used as a heat source for the heating device 16, so it is particularly suitable when the culture device 10 is large.

Further, as the cooling device 18, electronic cooling may be used. This utilizes the so-called Bertier effect, in which heat absorption or heat generation occurs at the junction when a current is passed through a junction of dissimilar metals or semiconductors. For example, by connecting an n-type semiconductor and a p-type semiconductor with a copper plate,
When current is passed through the shaped semiconductor, the copper plate that connects the two is cooled. According to electronic cooling that utilizes the Beltier effect, cooling can be performed simply by passing an electric current, thereby simplifying the equipment. Further, a heat generating part in electronic cooling may be used for heating.

Furthermore, if oxygen is required for culture, it is necessary to supply air or oxygen gas into the liquid 14. in this case,
Since these gases rise in the liquid 14, it is preferable to introduce these gases below the rising path of the liquid 14, such as the rising path 12a. This allows the so-called air lift effect of the supplied gas to be utilized for stirring.

In particular, in the case where the static mixer 26 is disposed in the rising passage 12a as shown in FIG. At the same time, oxygen dissolution can be effectively performed.

Further, FIGS. 5A9, B, and C show a preferred example of the static mixer 26 used in the present invention.

Static mixers 26 of various shapes are arranged inside the pipe-shaped partition wall 24 that forms a liquid flow path therein.

In the static mixer 26 shown in FIG. 5A, a rod-shaped central shaft 30 is provided with a number of rods 32 extending in the radial direction at predetermined intervals. And this rod 32 is
The angle with respect to the central axis 30 is shifted by 45 degrees, and the whole has a cut screw shape.

Therefore, the liquid flowing inside this static mixer 26 is
The resistance of the rods 32 twists the flow into a spiral, and the turbulence generated by each rod 32 effectively stirs the flow.

Furthermore, what is characteristic of this example is that each of the bars 32 is made of a permanent magnet.

For this reason, magnetic fields that are shifted by 45 degrees are formed in the static mixer 26 along the flow. When the liquid 14 passes through such a magnetic field, the activity of the organisms contained therein is increased, and the growth rate of the organisms is dramatically increased.

In the static mixer 26 shown in FIG. 5B, ribbon-shaped plates 34 twisted by 90 degrees are arranged in an aligned manner shifted by 90 degrees. This plate 34 is made of a permanent magnet.

This example also provides effective stirring and magnetic field effects similar to the example shown in FIG. 5A.

The static mixer 26 shown in FIG. 5C has a screw-shaped plate 36. A permanent magnet 38 is attached to the partition wall 24.
However, it is provided. These permanent magnets 38 have N poles,
A large number of them are provided by sequentially shifting the angles of each pair so that the S poles face each other.

Similar stirring and magnetic field effects can be obtained in this example as well.

The static mixer 26 using these permanent magnets is
When drinking water passes through this system, it can have beneficial effects on human health. Therefore, excellent effects can be exhibited even when applied to uses other than the culture device of the present invention.

[Effects of the Invention] As described above, according to the culture device of the present invention, there is no risk of damaging organisms even if sufficient stirring is performed, so the concentration of organisms in the culture tank can be increased, and the device can be made more compact. I can figure it out. Moreover, this can improve the productivity of useful substances.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing one embodiment of the present invention, FIG. 2 is an overall configuration diagram showing another embodiment, FIG. 3 is an overall configuration diagram showing another embodiment, and FIG. 4 is an overall configuration diagram showing another embodiment. FIGS. 5A, 5B, and 5C are front views showing an example of a static mixer 26 used in the present invention. 10...Culture device 12...Culture tank 14...Liquid 16...Heating device 18...Cooling device 24...Partition wall

Claims (3)

[Claims] (1) A culture tank for culturing organisms; a heating means for locally heating the liquid contained in the culture tank to generate an upward flow; and a heating means for locally cooling the liquid and causing an upward flow A culture device comprising: a cooling means that generates a countercurrent; (2) The culture apparatus according to claim 1, wherein the inside of the culture tank is partitioned into an upward flow passage and a downward flow passage by a partition wall. (3) The culture device according to claim 2, further comprising a static mixer provided inside either the upward flow passage or the downward flow passage.