JP2013085488A - Microalgae culturing and collecting apparatus and thermal power generation plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microalgae culturing and collecting apparatus for efficiently culturing and collecting microalgae by supplying oxygen to the nonphotosynthetic microalgae.SOLUTION: This microalgae culturing and collecting apparatus 10 adapted to culture and collect the nonphotosynthetic microalgae which absorbs organic matter to grow includes: an algal culture pool 11 for culturing the microalgae to grow in a culture solution filled with a predetermined quantity of liquid including the organic matter; a microbubble generator 20 for causing circulation convection by performing aeration that supplies pressurized air to an aeration nozzle 30 provided in the culture solution to generate microbubbles; a scum collecting device 40 disposed on the liquid surface of the culture solution; and a heat exchanger 50 disposed in the culture solution to radiate heat from the pressurized air.

Description

The present invention relates to a biomass-derived oil production plant, and more particularly, to a microalgae culture recovery device applied to non-photosynthetic microalgae that grow by absorbing organic matter.
The present invention also relates to a thermal power plant operated by receiving boiler fuel supplied from a microalgae culture recovery device.

  In recent years, microalgae containing an oil called “aulanthiochytrium” have attracted attention as “algae that produce petroleum”. This aurantiochytrium is a microorganism that forms a small cell population on organic matter in water, and is a heterotrophic organism that does not have chloroplasts and does not carry out photosynthesis, and grows by absorbing surrounding organic matter. In addition, it is said that auranthiochytrium has a growth power about 10 times that of, for example, the algae “Botriococcus” grown by photosynthesis.

Patent Document 1 below discloses a culture method in which suspended microalgae that are rapidly dispersed and have high photosynthetic ability can be easily recovered from suspended microalgae that are uniformly dispersed.
Patent Documents 2 and 3 listed below disclose a microalgae culture method and culture apparatus for growing microalgae by photosynthesis.
In Patent Document 4 below, carbon dioxide in combustion gas, which is a cause of global warming, is suitable for microalgae culture solution in a method of immobilizing by utilizing it for cultivation and growth of microalgae. A method for improving the sedimentation properties of algal bodies by irradiating light and separating algal bodies (solid content) and culture medium (liquid portion) efficiently and simply is disclosed.

JP 2011-62123 A Japanese Patent Laid-Open No. 7-246086 JP-A-7-250669 Japanese Patent Laid-Open No. 7-289240

By the way, non-photosynthetic microalgae such as auranthiochytrium require supply of oxygen for its growth. However, there is no efficient microalgae culture and recovery device suitable for culturing and collecting non-photosynthetic microalgae, that is, microalgae culture and recovery devices that efficiently cultivate and recover oxygen by supplying nonphotosynthetic microalgae. .
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a microalgae culture recovery device that supplies oxygen to non-photosynthetic microalgae for efficient culture recovery. is there. The present invention also relates to a thermal power plant that uses the microalgae cultured and recovered by the microalgae culture and recovery apparatus and generates power using the microalgae or biofuel (oil) produced from the microalgae as fuel for the boiler steam generator.

In order to solve the above problems, the present invention employs the following means.
The microalgae culture recovery device of the present invention is a microalgae culture recovery device for culturing and recovering non-photosynthetic microalgae that absorb and grow organic matter, in a culture solution filled with a predetermined amount of liquid containing organic matter An algae culture pool for cultivating and growing the microalgae, and microbubbles for generating circulatory convection by performing aeration to generate microbubbles by supplying pressurized air to an aeration nozzle disposed in the culture medium A generating device, a circulation device for supplying oxygen to the culture solution and forming a circulation flow, a scum recovery device arranged on the culture solution surface, and the pressurized air arranged in the culture solution And a heat exchanger that dissipates heat from the heat exchanger.

  According to such a microalgae culture recovery apparatus, the algae culture pool for cultivating and growing microalgae in a culture solution filled with a predetermined amount of liquid containing organic matter, and the aeration nozzle provided in the culture solution A fine bubble generator that generates a circulating convection by performing aeration by supplying pressurized air to generate fine bubbles, a scum recovery device disposed on the culture surface, and a pressurization disposed in the culture solution It is equipped with a heat exchanger that releases heat from the air, so microalgae cultured in the culture medium are supplied with oxygen necessary for growth by aeration, and are further circulated in the pool by circulating convection formed by aeration. By stirring, microalgae can be efficiently cultured to promote growth. Therefore, the microbubble generator is a device that supplies oxygen into the culture solution and forms circulating convection.

During the cultivation of such microalgae, heat is released from the pressurized air to the culture solution via a heat exchanger installed in the culture solution, so the temperature of the culture solution is adjusted to increase to an appropriate temperature. Can promote growth. Moreover, since the temperature of the air supplied to the aeration is lowered by performing heat radiation by the heat exchanger, the relative humidity of the air to be aerated is increased, and the fouling of the fine bubble generating device can be prevented.
Then, the microalgae that have been cultured are flowed into the circulation convection formed by aeration by operating the scum recovery device and recovered to the scum recovery device.

  In the above invention, the circulator is a microbubble generator that generates circulated convection by aeration by supplying pressurized air to an aeration nozzle disposed in the culture medium to generate microbubbles. The bubble generating device includes: a discharge unit that pressurizes air to form the pressurized air; a pressurized air supply pipe that supplies the pressurized air to the aeration nozzle; and moisture that supplies moisture to the pressurized air supply pipe It is preferable to supply moisture-containing air to the aeration nozzle provided with a supply means and provided with a diffuser film having a slit, whereby the moisture-containing air further increases the relative humidity described above. Therefore, it is possible to reliably prevent fouling in which deposits such as sea salt are clogged in the slit that discharges fine bubbles.

  In the microalgae culture recovery apparatus, the microalgae collected and collected in the scum recovery apparatus are stored in the algal culture pool by an ejector that branches and introduces a part of the pressurized air from the outlet of the discharge means. It is preferable to be sucked and collected to the outside, so that the microalgae that have been cultured can be collected in the scum collecting device by effectively using the discharge means of the fine bubble generating device.

  The thermal power plant of the present invention is manufactured from the microalgae collected from the microalgae culture and recovery apparatus according to any one of claims 1 to 3 and the microalgae culture and recovery apparatus directly or from the microalgae. A boiler steam generator that generates steam by burning the biofuel, and a steam turbine generator that generates power using a steam turbine operated by steam supplied from the boiler steam generator as a drive source. It is characterized by comprising.

  According to such a thermal power plant, the microalgae culture / recovery device according to any one of claims 1 to 3 is provided. Therefore, the microalgae efficiently cultured and recovered by the microalgae culture / recovery device. Steam is generated by a boiler steam generator that directly burns or by a boiler steam generator that burns biofuel produced from these microalgae, and the steam turbine and steam turbine generator are driven by this steam. It can generate electricity.

  In the above-mentioned thermal power plant, it is preferable to dissipate heat by introducing exhaust heat into an exhaust heat heat exchanger disposed in the culture solution from an exhaust heat recovery device provided downstream of the boiler steam generator. Thus, the growth of microalgae can be promoted by adjusting the temperature so that the temperature of the culture solution is raised to an appropriate temperature.

  In the above-mentioned thermal power plant, the discharge means is configured to be capable of increasing the pressure by selecting either the air or the combustion exhaust gas discharged from the boiler steam generator, thereby constituting a microalgae culture recovery device As for the microalgae cultured and recovered in one algae culture pool, it is possible to appropriately select either non-photosynthetic microalgae or photosynthetic microalgae for switching.

  The thermal power plant of the present invention includes an algae culture pool for culturing and growing non-photosynthetic microalgae that grow by absorbing organic matter in a culture solution filled with a predetermined amount of liquid containing organic matter, and in the culture solution. An air lift pump for supplying oxygen and forming a circulation flow, a scum recovery device disposed on the culture medium surface, and exhaust heat introduced from the exhaust heat recovery device disposed in the culture medium to dissipate heat. A microalgae culture recovery device equipped with a waste heat exchanger and the microalgae recovered by the microalgae culture recovery device directly or by burning biofuel produced from the microalgae to generate steam And a steam turbine generator that generates power using a steam turbine operated by steam supplied from the boiler steam generator as a drive source. It is intended to.

  According to such a thermal power plant, the microbubble generator employs an air lift pump that facilitates maintenance instead of the microbubble generator as a device that supplies oxygen into the culture solution and forms circulating convection. Furthermore, an exhaust heat exchanger that introduces exhaust heat from the exhaust heat recovery device and dissipates it for heating the culture solution is adopted, and even with such a configuration, the microalgae culture recovery device can efficiently culture Steam is generated in a boiler steam generator that directly burns the recovered microalgae, or in a boiler steam generator that burns biofuel produced from the microalgae, and steam is used to generate steam turbines and steam turbine generators. Can be driven to generate electricity.

  According to the present invention described above, it is possible to provide a microalgae culture recovery device that supplies oxygen to non-photosynthetic microalgae and efficiently cultures and recovers them. Moreover, it becomes possible to operate a thermal power plant that uses the microalgae cultured and recovered by the microalgae culture and recovery apparatus and generates power using the biofuel (oil) produced from the microalgae or microalgae as boiler fuel.

It is a schematic block diagram which shows one Embodiment about the micro algae culture collection apparatus which concerns on this invention. As an example of a circulation apparatus, it is a figure which shows the example of arrangement | positioning of the aeration nozzle of the microbubble generator which generates a microbubble in a culture solution, (a) is a top view, (b) is a front view. It is sectional drawing which shows the internal structural example of an aeration nozzle. It is a block diagram which shows the outline | summary in the case of using a micro algae as boiler fuel of a thermal power plant. It is a schematic block diagram which shows the structural example which applied the microscopic culture collection | recovery apparatus shown in FIG. 1 to a thermal power plant. It is a top view which shows the 1st arrangement example about algae culture pool arrangement | positioning of the micro algae culture collection | recovery apparatus in a thermal power plant. It is a perspective view which shows the other structural example which employ | adopted the air lift pump about the circulation apparatus applied to the algae culture pool of the micro algae culture collection apparatus applied to a thermal power plant. It is a top view which shows the 2nd example of arrangement | positioning about the algae culture pool arrangement | positioning of the micro algae culture collection apparatus in a thermal power plant.

Hereinafter, one embodiment of a microalgal culture collection device and a thermal power plant concerning the present invention is described based on a drawing.
A thermal power plant 1 shown in FIG. 4 includes a microalgae culture and recovery device 10, a microalgae drying and grinding device 2, a boiler steam generator 3, a steam turbine generator 4, a flue gas treatment device 5, The heat recovery device 6 and the chimney 7 are roughly configured. Among these, the boiler steam generator 3 generates steam by directly combusting the pulverized microalgae as fuel, and the generated steam is supplied to the steam turbine generator 4.

The steam turbine generator 4 includes a steam turbine that is operated by supply of steam, and a generator in which the main shaft is connected to the steam turbine, and the generator is driven by the driving force of the steam turbine. Power generation.
The flue gas generated by the combustion of the fuel in the boiler steam generator 3 is a high-temperature gas containing substances that normally have an adverse effect on the environment, and passes through the flue gas treatment device 5 to remove desulfurization, denitration, etc. Is given. Thereafter, the high-temperature combustion exhaust gas is sent to the exhaust heat recovery device 6, and after the exhaust heat retained by the combustion exhaust gas is recovered, it is released from the chimney 7 to the atmosphere.
Note that the boiler steam generator 3, the steam turbine generator 4, the smoke treatment device 5, the exhaust heat recovery device 6, and the chimney 7 existing in the frame indicated by the broken line in the figure are the fuel used by the boiler steam generator 3. It constitutes a different conventional thermal power plant.

The above-described microalgae culture and recovery apparatus 10 of the thermal power plant 1 is an apparatus for culturing and recovering, for example, “aulanthiochytrium” as non-photosynthetic microalgae that grow by absorbing organic matter.
A microalgae culture recovery apparatus 10 shown in FIG. 1 includes an algae culture pool 11 for cultivating and growing microalgae in a culture solution filled with a predetermined amount of liquid containing organic matter, and an aeration nozzle disposed in the culture solution. A microbubble generator (circulator) 20 that generates circulated convection by aeration that supplies pressurized air to the microbubbles, a scum recovery device 40 disposed on the culture medium surface, and a culture medium. And a heat exchanger 50 that dissipates heat from the pressurized air.

The algae culture pool 11 is filled with a culture solution such as seawater containing organic matter to a predetermined depth, and is agitated by forming a circulating convection by aeration that generates fine bubbles in the culture solution. Since the culture solution in the algae culture pool 11 needs to maintain the desired water quality and water depth suitable for the cultivation of microalgae, the organic substance supply line 12 that supplies additional organic substances that serve as food for the microalgae, A culture solution supply line 13 for supplying the solution is provided.
In this case, in order to form a large circulation convection (arrow F in the figure) in the culture solution in the algae culture pool 11, it is desirable to generate aeration fine bubbles from the vicinity of the bottom surface in the vicinity of the inner end of the pool. For this reason, it is desirable that the scum recovery device 40 be disposed on the culture liquid surface which is substantially diagonal from the position where the fine bubbles are generated.

Further, in order to supply oxygen necessary for the growth of microalgae into the algae culture pool 11, a microbubble generator 20 is provided that can generate microbubbles in the culture solution and form a circulating convection by aeration.
The fine bubble generating device 20 includes a blower (discharge means) 21 that pressurizes air introduced from the atmosphere to form pressurized air, a pressurized air supply pipe 22 that supplies pressurized air to the aeration nozzle 30, and pressurization A humidifier (moisture supply means) 23 for supplying moisture to the air supply pipe 22 is provided.

  That is, in the fine bubble generating device 20 of the present embodiment, the aeration nozzle 30 includes the diffuser film 31 having the slits 32, and the humidification device 23 is provided so that pressurized air containing moisture is supplied to the aeration nozzle 30. It comes to be supplied. Such humidification of the pressurized air is effective for preventing fouling due to precipitates in the aeration nozzle 30.

The pressurized air pumped from the blower 21 is supplied to the aeration nozzle 30 through the pressurized air supply pipe 22, and the pressurized air supply pipe 22 leading to the aeration nozzle 30 is sequentially supplied from the discharge side of the blower 21. A branch valve 24, a heat exchanger 50, and a humidifier 23 are disposed.
The branch valve 24 is an on-off valve that selectively switches the flow direction of the pressurized air, and may be configured by combining a three-way valve or two on-off valves. The supply destination of the pressurized air that is selectively switched by the branch valve 24 is the aeration nozzle 30 of the fine bubble generating device 20 or the ejector 43 of the scum recovery device 40 described later.

Here, as a configuration example of the aeration nozzle 30, a case where the diffuser film 31 is rubber will be described with reference to FIGS.
The aeration nozzle 30 is a rubber diffuser film 31 that covers the periphery of a base material 33 and is provided with a large number of small slits 32 and is generally called a “diffuser nozzle”. Such an aeration nozzle 30 opens a slit 32 and discharges a large number of fine bubbles of substantially equal size when the diffuser film 31 expands due to the pressure of the pressurized air supplied from the pressurized air supply pipe 22. Can do.

  The aeration nozzle 30 is attached to a header pipe 22 a provided in a plurality of branch pipes branched from the pressurized air supply pipe 22 via a flange 34. The pipe from the pressurized air supply pipe 22 to the header pipe 22a is made of a resin pipe or the like in consideration of corrosion resistance, for example, when seawater is used as a culture solution.

For example, as shown in FIG. 3, the aeration nozzle 30 uses a substantially cylindrical support 33 made of resin in consideration of corrosion resistance against seawater and the like, and a large number of slits 32 so as to cover the outer periphery of the support 33. After covering with a rubber diffuser film 31 formed with, the left and right ends are fixed with a fastening material 34 such as a wire or a band.
Further, the above-described slit 32 is in a closed state in a normal state where no pressure is applied. In the fine bubble generating device 20, the slit 32 is always open when pressurized air is supplied.

One end 33a of the support 33 described above enables introduction of pressurized air while attached to the header pipe 22a, and the other end 33b is opened to allow introduction of a culture solution.
For this reason, the one end 33 a side communicates with the inside of the header pipe 22 a through the air inlet 33 c penetrating the header pipe 22 a and the flange 34. Further, the inside of the support 33 is divided by a partition plate 33d provided in the axial direction of the support 33, and the flow of pressurized air is blocked by the partition plate 33d.

Further, on the side surface of the support 33 that is closer to the header pipe 22a than the partition plate 33d, the air diffuser 31 is pressurized and expanded between the inner peripheral surface of the diffuser membrane 31 and the outer peripheral surface of the support. Air outlets 33e and 33f for allowing pressurized air to flow into the space 31a to be opened are opened.
Therefore, the pressurized air flowing into the aeration nozzle 30 from the header pipe 22a flows into the inside of the support 33 from the air inlet 33c as shown by an arrow in the figure, and is then added from the side air outlets 33e and 33f. It will flow out to the pressure space 31a.
The fastening member 34 described above fixes the diffuser membrane 31 to the support 33 and prevents air flowing in from the air outlets 33e and 33f from leaking out from both ends.

In the aeration nozzle 30 configured as described above, the pressurized air that flows in from the header pipe 22a through the air inlet 33c flows out to the pressurized space 31a through the air outlets 33e and 33f, and is initially slit. Since 32 is closed, it accumulates in the pressurizing space 31a and raises the internal pressure. As a result of the increase in the internal pressure in the pressurized space 31a, the diffuser membrane 31 expands due to the increased pressure in the pressurized space 31a, and the slit 32 formed in the diffused membrane 31 opens to open the compressed air. Allow microbubbles to flow into the culture.
The generation of such fine bubbles is performed in all aeration nozzles 30 that receive air supply from the blower 21 through the pressurized air supply pipe 22 and through the branch and header pipes 22a.

The scum recovery device 40 is an apparatus that is disposed on the culture liquid level in the algal culture pool 11 and separates and recovers the microalgae floating on the culture liquid level from the culture liquid when the culture of the microalgae is completed. . This scum recovery device 40 is movable between the position of the step of growing microalgae indicated by a broken line in the figure and the position of the step of recovering microalgae indicated by a solid line. The water line is positioned higher than the liquid level, so that microalgae are not collected.
The completion of the culture of the microalgae is, for example, a case where it is determined that the microalgae have grown by absorbing a predetermined amount of organic matter, and the amount of organic matter absorption is the amount of organic matter added from the organic matter supply line 12 or the like. The amount of organic matter remaining in the pool can be calculated.

The illustrated scum recovery device 40 is a float type disposed around the vertical wall of the algae culture pool 11, and in the microalgae recovery process, the scum composed of the microalgae M flowing and floating on the culture liquid surface by the circulating convection described above is used. It introduce | transduces in the collection | recovery container 41 of a float part, isolate | separates the micro algae M from a culture solution, and collect | recovers.
In this case, the collection container 41 of the scum collection device 40 is set in a state in which the height of the inlet is set higher than the draft line by means of buoyancy adjustment, a lift device or the like in the growth process of the microalgae M, and the microalgae M is not collected. However, the entrance height is lowered to the waterline when collecting microalgae.
Moreover, the air flow of the aeration nozzle 30 is increased at the time of scum recovery, and the recovery rate of the grown microalgae M is improved.

The microalgae M separated and recovered in the recovery container 41 is sucked by an ejector 43 provided in the middle of the algae recovery pipe 42 and guided to the next process. Specifically, the collected microalgae M is directly burned by the boiler steam generator 3 through the microalgae drying and pulverizing apparatus 2 or supplied to a biofuel manufacturing apparatus (not shown).
The ejector 43 is discharged to the atmosphere through the ejector 43 by operating the branch valve 24 and changing the flow path of the pressurized air pumped from the blower 21 from the pressurized air supply pipe 22 to the branch pipe 44. The microalgae M are sucked from the collection container 41 by the negative pressure formed by the flow of pressurized air.

  The heat exchanger 50 is disposed in the culture medium and becomes a heater that radiates heat from the pressurized air and raises the temperature of the culture liquid. That is, since the temperature of the air pressurized by the blower 21 rises, if the pressurized air fed from the blower 21 is introduced into the heat exchanger 50, the culture solution can be heated by the heated air.

On the other hand, since the heated air that has passed through the heat exchanger 50 dissipates heat to the culture solution and falls in temperature, the humidity of the heated air relatively increases. For this reason, for example, when seawater is used as the culture solution, salt or the like in the seawater in the seawater hardly deposits as seawater salt in the slit 32 of the aeration nozzle 30.
In other words, the deposit adhered to the slit 32 increases the pressure loss of the diffuser film as a result of narrowing the slit gap or closing the slit, but precipitates by increasing the humidity of the heated air. The problem of fouling caused by things can be solved. Such elimination of fouling is also effective for humidification of pressurized air by the humidifier 23 described above.

  The microalgae culture recovery apparatus 10 configured in this manner is supplied with oxygen necessary for growth of microalgae cultured in a culture solution by aeration, and the inside of the pool is agitated by circulating convection formed by aeration. Therefore, microalgae can be efficiently cultured to promote growth. The microalgae that have been cultured in this way are caused to flow into the circulation convection formed by aeration by operating the scum recovery device 40, flow into the recovery container 41, and are recovered by the scum recovery device 40.

During the cultivation of microalgae, heat is released from the pressurized air to the culture solution via the heat exchanger 50 installed in the culture solution, so that the temperature of the culture solution is adjusted to increase to an appropriate temperature. Can promote growth.
By the way, when the microalgae are auranthiochytrium, the doubling time of the algae by culturing, that is, the time until the cultivated algae grows and doubles is about 12 hours at 10 ° C. It is said to be about 4.2 hours at 20 ° C. and about 2.1 hours at 30 ° C. Therefore, heating the culture solution using heat radiation of the pressurized air by the heat exchanger 50 is effective for efficiently growing microalgae with low energy in addition to the above-described prevention of fouling. .

By the way, when the above-described microalgae culture recovery device 10 is applied to the thermal power plant 1, for example, exhaust heat can be supplied from the exhaust heat recovery device 6 or the like.
Therefore, for example, as in the microalgae culture recovery device 10A shown in FIG. 5, exhaust heat is exhausted from the exhaust heat recovery device 6 provided downstream of the boiler steam generator 3 to the exhaust heat heat exchanger 60 disposed in the culture solution. It can be introduced to dissipate heat.

By utilizing such exhaust heat, the growth of microalgae can be promoted by adjusting the temperature so that the temperature of the culture solution is raised to an appropriate temperature. That is, in addition to the heating temperature increase by the heat exchanger 50 described above, the heating temperature increase by the exhaust heat exchanger 60 is also possible, so that the temperature adjustment is facilitated by increasing the heating ability of the culture solution.
In particular, since it becomes easy to adjust the temperature of the culture solution to a high temperature so that the growth rate of the microalgae increases, the microalgae can be efficiently grown with low energy by effectively utilizing the exhaust heat. In addition, the code | symbol 61 in a figure is exhaust heat supply piping.

Further, in the microalgae culture recovery apparatus 10A shown in FIG. 5, the blower 21 of the microbubble generator 20 selects either air or combustion exhaust gas discharged from the boiler steam generator 3 by opening and closing the on-off valve. Thus, the voltage can be boosted.
With such a configuration, as for the microalgae cultured and recovered in one algae culture pool 11 constituting the microalgae culture collection device 10A, either one of non-photosynthetic microalgae or photosynthesis microalgae is appropriately selected. It becomes possible to switch.

That is, if the air sucked from the atmosphere is boosted by the blower 21, aeration is performed by the fine air bubbles released into the algae culture pool 11, so that the culture device can culture non-photosynthetic microalgae that require oxygen It becomes. However, if the combustion exhaust gas subjected to the flue gas treatment is boosted by the blower 21, aeration is performed mainly by the fine bubbles of carbon dioxide released into the algae culture pool 11, so that the photosynthesis fine algae that require carbon dioxide are used. It becomes a culture device which can culture.
FIG. 6 shows an arrangement example of the microalgae culture recovery device 10A when the above-described microalgae culture recovery device 10A is applied to a large-scale thermal power plant.

Further, the microalgae culture recovery device 10B shown in FIG. 7 replaces the microbubble generator 20 described above as a circulation device that supplies oxygen into the culture solution in the algae culture pool 11 and forms a circulation flow of the culture solution. An air lift pump 70 is employed.
The air lift pump 70 supplies air to a tubular pump body 73 having a culture medium inlet 71 at one end and a culture medium outlet 72 at the other end, and when the air rises inside the pump body 73, the inside culture is performed. A flow is formed by pulling up the liquid. In addition, in the microalgae culture collection | recovery apparatus 10B shown in FIG. 7, illustration regarding an exhaust heat supply system, an organic substance supply system, etc. is abbreviate | omitted.

The culture medium inlet 71 of the pump body 73 opens to the side wall near the bottom of the pool, and the culture liquid outlet 72 flows down the pulled culture liquid toward the receiving surface 15 provided on the culture liquid surface in the pool. Is open.
The culture solution dropped on the receiving surface 15 flows through the U-shaped flow path formed by the partition wall 16 dividing the inside of the pool as indicated by arrows f1 to f3, and is again sucked into the air lift pump 70 from the culture solution inlet 71. Therefore, a circulating flow of the culture solution is formed in the pool. At this time, the air supplied to the air lift pump 70 becomes bubbles, and oxygen necessary for the growth of microalgae is supplied.
FIG. 8 shows an arrangement example of the microalgae culture recovery device 10B when the above-described microalgae culture recovery device 10B is applied to a large-scale thermal power plant.

Since the thermal power plant employing such a microalgae culture recovery device 10B employs the air lift pump 70 as the circulation device, the maintenance in the culture solution is greater than that in which many aeration nozzles 30 are present in the culture solution. There are almost no target parts.
Therefore, the apparatus can be easily maintained, and the exhaust heat of the thermal power plant 1 can be used by the exhaust heat exchanger 60. Therefore, the temperature of the culture medium in the pool can be adjusted by heating. .

  That is, also in the thermal power plant 1 provided with the microalgae culture recovery device 10B of the present embodiment, the microalgae is efficiently cultured and recovered, similarly to the plant provided with the microalgae culture recovery device 10 described above. Steam is generated by the boiler steam generator 3 that directly burns microalgae or by the boiler steam generator 3 that burns biofuel produced from the microalgae, and steam is used to generate steam turbines and steam turbine generators 4. Can be driven to generate electricity.

As described above, according to this embodiment described above, non-photosynthetic microalgae can be generated with high efficiency and low energy, and microalgae-derived fuel is mass-produced at low cost as fuel for thermal power plants. It becomes possible.
In addition, this invention is not limited to embodiment mentioned above, In the range which does not deviate from the summary, it can change suitably.

DESCRIPTION OF SYMBOLS 1 Thermal power plant 2 Microalgae drying crusher 3 Boiler steam generator 4 Steam turbine generator 10, 10A, 10B Microalgae culture collection device 11 Algae culture pool 20 Microbubble generator (circulation device)
21 Blower 22 Pressurized air supply pipe 22a Header pipe 23 Humidifier (moisture supply means)
24 Branch valve 30 Aeration nozzle 31 Air diffuser film 32 Slit 40 Scum recovery device 41 Recovery container 43 Ejector 50 Heat exchanger 60 Waste heat exchanger 70 Air lift pump (circulation device)
M microalgae

Claims (7)

A microalgae culture collection device for culturing and collecting non-photosynthetic microalgae that grow by absorbing organic matter,
An algal culture pool in which the microalgae are cultured and grown in a culture solution filled with a predetermined amount of liquid containing organic matter;
A fine bubble generator for generating circulating convection by performing aeration to supply pressurized air to an aeration nozzle disposed in the culture medium to generate fine bubbles;
A scum recovery device disposed on the culture surface;
A heat exchanger disposed in the culture medium and dissipating heat from the pressurized air;
A microalgae culture collection device comprising:   The fine bubble generating device is configured to discharge air to pressurize air into the pressurized air, supply pressurized air to the aeration nozzle, and supply moisture to the pressurized air supply piping. The microalgae culture collection apparatus according to claim 1, wherein air containing water is supplied to the aeration nozzle provided with a water supply means for performing aeration and having a diffuser membrane having a slit.   The microalgae collected and collected in the scum recovery device are collected by suction to the outside of the algae culture pool by an ejector that branches and introduces a part of the pressurized air from the outlet of the discharge means. The microalgae culture collection apparatus according to claim 2.   The microalgae culture collection device according to any one of claims 1 to 3 and the microalgae collected by the microalgae culture collection device are burned directly or by biofuel produced from the microalgae. A boiler steam generator that generates steam, and a steam turbine generator that generates power using a steam turbine operated by steam supplied from the boiler steam generator as a drive source. And thermal power plant.   The thermal power according to claim 4, wherein exhaust heat is introduced into the exhaust heat exchanger and dissipated from an exhaust heat recovery device provided downstream of the boiler steam generator to dissipate heat. Power plant.   6. The thermal power plant according to claim 4, wherein the discharge means is configured to be capable of boosting pressure by selecting either the air or the combustion exhaust gas discharged from the boiler steam generator. . An algae culture pool for culturing and growing non-photosynthetic microalgae that grow by absorbing organic matter in a culture solution filled with a predetermined amount of liquid containing organic matter, supplying oxygen to the culture solution and circulating the flow An air lift pump to be formed, a scum recovery device disposed on the culture medium surface, and a waste heat heat exchanger disposed in the culture fluid to introduce exhaust heat from the exhaust heat recovery device and dissipate heat. A microalgae culture recovery device,
A boiler steam generator for generating steam by burning the biofuel produced from the microalgae directly or directly with the microalgae recovered by the microalgae culture recovery device;
A steam turbine generator for generating power using a steam turbine operated by steam supplied from the boiler steam generator as a drive source;
A thermal power plant characterized by comprising:

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