JPH0785712B2 - Algae culture 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 apparatus for culturing microalgae such as chlorella and spirulina.

[0002]

2. Description of the Related Art Microalgae such as chlorella and spirulina are rich in proteins, fats and oils, vitamins and other physiologically active substances, and are therefore useful as raw materials for health foods, feeds, feeds and the like. In recent years, large-scale culture of chlorella or the like that absorbs carbon dioxide by carbon assimilation has also attracted attention as a means for fixing carbon dioxide, which causes global warming. Therefore, there have been many proposals for a culture apparatus for microalgae such as Chlorella, and the main ones are as follows. Open pond culture method Open circulation culture method Open channel culture method Glass flat bottle culture method Vertical cylindrical culture method

Among these, the open type which allows large-scale culture has a drawback that other algae are apt to be mixed with and various bacteria are contaminated, and the quality and yield of harvested algae are not stable. Further, in the culturing method using sunlight, in order to expand the light-receiving surface, the culture device must be expanded horizontally, but since the light-receiving surface cannot be made larger than the installation area of the culture device, large-scale culture is possible. To do that requires a vast site. Aseptic culture is possible with the culture method using a glass flat bottle, but mass culture is not possible.

In the vertical cylindrical culture method, a cylindrical culture tank made of a light-transmitting material such as glass or acrylic resin is blown with air to cultivate while irradiating with light, so that large-scale culture is possible, and different types of culture are possible. It has the feature that it is unlikely to be contaminated with algae and other bacteria. However, in this type of conventional device, a light source for illumination is arranged around the culture tank, and therefore, there is a limit to the reflection of the culture tank surface and the condensing ability of the lighting device, so that the culture tank is actually used. The light incident on the culture medium was only a part of the light emitted from the light source, and the energy utilization efficiency was poor. In addition, the lighting device installed around the culture tank,
Not only occupies a large floor area, but also hinders the use of sunlight.

As for the light source of the illuminating device, the flood lamp which can obtain high illuminance is also likely to cause the temperature rise of the culture solution because the irradiation amount of the heat ray is large. There was a problem that it was difficult. There is also a method of illuminating the culture solution by introducing sunlight or (and) artificial light into the culture tank using an optical fiber.
Since the light is considerably attenuated in the optical fiber, the lighting efficiency is not so good, and since the optical fiber is not easily washed at the end of the culture, it has not been applied to an industrial large-scale culture tank.

[0006]

DISCLOSURE OF THE INVENTION An object of the present invention is to improve the culture tank illuminating means in the conventional algae cultivating apparatus, which has both advantages and disadvantages as described above, and to achieve high illumination efficiency with a low calorific value. To do.

[0007]

The algae culturing apparatus successfully provided by the present invention comprises a cylindrical culturing tank made of a transparent material, which is vertically arranged, and a lighting device irradiates the culture solution in the culturing tank with light. However, the algae culture device for culturing algae is characterized by using, as a lighting device, a single-ended type fluorescent lamp installed so that the glass tube portion that emits light is immersed in the culture solution.

The single-ended type fluorescent lamp used in the algae culture device of the present invention is one in which both base portions having discharge electrodes are arranged at one end in the longitudinal direction of the fluorescent lamp.
The glass tube portion has two glass tubes arranged in parallel, a glass tube bent into a U shape, or two of these.
There is a combination of the above. The glass tube portion of this single-ended type fluorescent lamp is attached to the culture tank so that it is immersed in the culture solution. It is desirable to arrange the base part and the stabilizer outside the culture tank, but if sufficient insulation is possible, they can be installed in the gas phase part above the culture tank.

[0009]

In the algae culture by the culture device of the present invention,
The culture solution is directly irradiated with light by a fluorescent lamp whose light-emitting portion is immersed in the culture solution. The light emitted by the fluorescent lamp illuminates a 100% culture solution and is utilized for carbon assimilation of algae at a high utilization rate. Since there is no lighting equipment around the culture tank, sunlight can be made to enter from the culture tank wall during the daytime, and the fluorescent lamp can be turned off or dimmed to save the electricity cost for lighting.

[0010]

EXAMPLES In the illustrated embodiment, the culture tank 1 is formed by attaching a stainless steel bottom plate 3 and an acrylic resin top plate 4 to an upright acrylic resin cylinder 2 to form a culture tank body, and further, venting the bottom plate 3. A diffuser plate 5 for water is attached, and a water passage pipe 6 for temperature control is fixed at an appropriate position in the tank. The diffuser plate 5 is made of porous ceramics and is connected to the air supply device 8 by a pipe 7. The air supply device 8 is composed of a compressor 9 for air pressure feeding, a carbon dioxide gas cylinder 10 for supplying carbon dioxide gas, a flow rate control device 11 for adjusting the amount of ventilation, an air filter 12 for cleaning ventilation, etc., and has a constant concentration of carbon dioxide gas. It is possible to supply the air having a raised level to the diffuser plate 5 at a constant flow rate.

The water pipe 6 is a water supply device 13 whose temperature can be adjusted.
Is supplied to the water supply device 8 to supply cold water or hot water having a constant temperature to cool or warm the culture solution and maintain the culture solution temperature at a suitable value. The single-ended fluorescent lamps 14 and 15 for illuminating the inside of the culture tank 1 are composed of two glass tubes a and b in which one unit is arranged in parallel, and are upright with the base portion 16 facing upward. A base portion 16 is supported by the top plate 4. The base portion 16 is connected to a power source via a ballast 17. The top plate 4 has an exhaust pipe 1
8 and the bottom plate 3 further has a culture solution supply / discharge port (not shown).

Next, a culture experiment of chlorella (Chlorella pyrenoidosa) using this culture device will be described.
The culture conditions were as follows. Cultivation tank: Cylinder culture tank made of acrylic resin with inner diameter of 11 cm and capacity of 7,500 ml Culture medium temperature: 27 ° C Illumination: Two 96W single-ended fluorescent lamps (illuminance at center of culture tank: 40 klux) Initial algal cell concentration: 0.0 8g / l Aeration rate: 2000ml / min Carbon dioxide concentration of blown air: 5% Culture solution (MC medium) Composition:

1
Culture was continued for 7 days while collecting and analyzing the culture solution once a day. As a comparative example, a culture experiment was conducted under the same conditions except that the illumination by the single-ended type fluorescent lamp was stopped and eight 20 W straight tube fluorescent lamps were arranged around the culture tank to perform illumination with an illuminance of 20 klux. The experimental results are shown in Tables 1 and 2. The algal cell concentration and the production amount are both dry matter equivalent values.

[0014] Since the power consumption of this example is 96 W × 2 = 192 W and the power consumption of the comparative example is 20 W × 8 = 160 W, the daily algal production amount per 1 W of power consumption is 2 in the case of this example.
It was 3.4 mg, and in the case of the comparative example, it was 18.1 mg, which shows that the lighting efficiency of this example is good.

[0015]

As described above, according to the device of the present invention which uses the single-ended type fluorescent lamp in which the glass tube portion is soaked in the culture solution as a lighting device, the conventional culture with a lighting device is performed. The lighting efficiency is much higher than that of the device, and efficient culture can be performed with low energy consumption. Further, compared with the conventional culture device in which the lighting device is installed around the culture tank, the installation floor area is small and there is an advantage that sunlight can be sufficiently used in the daytime.
Since the fluorescent lamp immersed in the culture solution can be easily washed, it is superior in both workability and illumination efficiency to the method of immersing the optical fiber in the culture solution.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

[Explanation of symbols]

1: Cultivation tank 2: Acrylic resin cylinder 3: Bottom plate 4: Top plate 5: Air diffuser plate 8: Air supply device 10: Carbon dioxide gas cylinder 14, 15: Single-ended fluorescent lamp 16: Base part 18: Exhaust pipe

Claims (1)

[Claims] 1. An algae culture device in which a cylindrical culture tank made of a transparent material is vertically arranged and an alga is cultured while irradiating a culture solution in the culture tank with light by a lighting device,
An algae cultivating device, which uses a single-ended gold fluorescent lamp installed so that a light-emitting glass tube portion is immersed in a culture solution as the illuminating device.