JP2010518881A - Techniques and cultivation equipment for promoting algae growth on water - Google Patents

Abstract

  A method and apparatus for promoting the growth of algae with an apparatus constructed on water such as the sea or lake. In the apparatus, there is a water storage part or a sealing part consisting of an impermeable membrane or lining, and algae is placed in a part separated from the surrounding sea water. The floating structure floats at different levels of seawater so that algae flow from the reservoir to the base at high tide and from the base to the reservoir at low tide.

Description

  The present invention relates to a technique and an apparatus for cultivating aquatic algae in an apparatus constructed on the surface of a water such as a sea or a lake by a technique for reducing costs related to operation and land use.

  The use of algae is well known in many industries. For example, gels, suspending agents, anti-decomposition agents, and emulsifiers that are contained in algae are consumed and utilized in the fields of the cosmetics industry and the paint industry. In agriculture, it can be mixed with poultry feed or fertilized as crop fertilizer. Some algae also have unique medicinal properties. For example, these algae are rich in omega-3 fatty acids. Algae can also produce fuels such as biodiesel and biomass that can generate electricity when burned.

  Algae grown naturally in the sea and lakes support the aquatic food chain as a source of food and oxygen for most aquatic organisms, and are the basis for aquatic organisms and fisheries. Recent efforts in commercial algae cultivation have been concentrated on algae cultivation on instant and enclosed soils.

  The object of the present invention is the cultivation of algae on a device built on the sea or other water. In the apparatus, the moisture necessary for the growth of algae is secured by a sheet of vinyl, rubber or other impermeable material. The water necessary for growth is secured by a sealed device that is adjusted to discharge excess carbon dioxide that is empty at the top or enters the device.

  A further object of the present invention is to reduce the cost of algae cultivation using tidal currents and wave energy. In addition, it is possible with the present invention to make the best use of the sea temperature with low fluctuations for the growth of algae.

  Yet another objective is to integrate a series of processes that can maximize efficiency and reduce costs.

  The first feature of the present invention is the use of tidal currents to reduce the cost of pumping and draining. For example, at high tide, the water that grows algae flows from the offshore device to the land at low tide level, and similarly at low tide the seedling algae can flow from the high tide level to the device at sea. it can. This reduces the main cost of growing algae on land.

  Second, the device can provide effective use of ocean waves. By using waves, water and algae in the apparatus can be agitated and the natural growth of algae can be promoted by using waves so that all algae are uniformly exposed to sunlight by continuous stirring. This can reduce another major expense in cultivating algae on land.

  Thirdly, the device can grow algae in a body of water separated from the surrounding body of water. The top of the device can be opened and can be sealed with a valve to expel excess carbon dioxide.

  Fourthly, the present apparatus can utilize the ash obtained by burning algae and minerals in seawater condensed by residual heat when supplying nutrients to plants.

  Fifth, the present apparatus can keep temperature fluctuations in the culture medium low by utilizing a moderate temperature difference such as the sea due to the heat exchange surface of the container in the apparatus.

  Furthermore, in order to grow algae that can produce much more biodiesel than any other plant cultivated for the same purpose, at sea, especially land cannot be secured sufficiently, or land prices are expensive In places, the device is easy to use. In addition, algae cultivation in the sea has the advantage that it does not compete with land use necessary for the production of food crops.

  The basement is constructed on the shore behind the barrier so that the basement slopes from a higher water level than the high tide line to a lower water level than the low tide line. These water levels are actually based on natural ocean shorelines, and no civil engineering work is required to create the gradient.

  The algae nursery is placed at or above the high tide line, and water containing algae can flow toward the lower tides. Each separate floating structure becomes an alternative nursery.

  Algae grows on a floating structure. Bamboo structure can be used to flow or hold sheets made of materials such as vinyl, rubber, rubberized cloth, so as to form an impermeable pool separated from the surrounding water Built with a framework made of materials such as wooden or hollow plastic. This pool can be sealed or opened.

  One example of such a structure is a 20 meter square or other size framework. A film is attached inside or outside so that water can be poured.

  They can be supported on the sea surface or in many cases mutually in any of the existing ways to prevent running away.

  When these structures are constantly in contact with each other by wave motion, it will be necessary to reinforce and absorb the impact, for example by putting old tires on all sides.

  During the algae harvest season, water and algae flow into a pond behind the barrier at sea level similar to or below the low tide line.

  Grown algae oils itself, and the residue is used for human and fish, other marine life food sources, ethanol production as a fuel by fermentation, methane production by anaerobic digestion, and direct for medical and health purposes It can be used for various purposes such as electric machine generation. Algal oil, similar to fish oil, has a variety of uses and is also used for biodiesel production.

  In one embodiment, the fermented product is used to produce ethanol that can be used for biodiesel production, sold as a petroleum substitute, the residue is burned for electricity generation, the remaining ash is turned into algae fertilizer, and surplus Heat can be used to evaporate the cone to provide the algae with more nutrition. Carbon dioxide produced in the fermentation process does not contain impurities, and good quality can be used for algae growth.

  All operations on land, such as algae harvesting, oil extraction, and biodiesel production can generate electricity. Surplus electricity can also be sold on the grid.

  The size, shape, and structure of the floating structure is designed to optimize the agitation action. For example, if more stir action is needed, adding more bamboo or other levitation devices can increase the buoyancy on the side facing the incoming wave and can be lifted further by the wave. Another way to change the agitation method is to adjust the length of the floating structure along the path of the waves. For example, the degree of mixing varies depending on whether the length of the structure is the same as the wave length or 1.5 times the wave length.

  Both freshwater algae and seawater algae can grow in this floating structure. In fact, it grows well in the sea where there are no other organisms that threaten freshwater algae habitat, and seawater algae also grow in freshwater. Desirable species contamination is a significant problem in algae cultivation on land.

  In order to protect the desired species growing in the floating structure from contamination and exchange by more aggressive and undesirable native species, a closed structure on land is sometimes used. One of the serious problems with such a closed structure is its environment, which is similar to a greenhouse, and the sun's fence. This raises the temperature and affects the growth of algae in the growth medium. Exquisite contact with the sea allows for greater heat exchange, and the temperature of the growth medium and the algae itself are kept much better for algae growth.

Claims (8)

    A floating device for cultivating algae with water like seawater. In the apparatus, there is a water storage part or a sealing part consisting of an impermeable membrane or lining, and algae is placed in a part separated from the surrounding sea water. A floating structure that floats at different levels of seawater so that algae flow from the reservoir to the base at high tide and from the base to the reservoir at low tide.     In the apparatus for cultivating algae floating on the sea described in claim 1, the water storage part is floated by waves in the apparatus, and the algae are constantly stirred by the waves and evenly exposed to sunlight.     In the apparatus for cultivating algae floating on the sea described in claims 1 and 2, the apparatus itself is composed of a bamboo stick and plastic or the like.     In the algae cultivation apparatus which floats on the sea described in claims 1, 2 and 3, it can be lifted by adding a bamboo stick to the part facing the wave, and the stirring motion can be increased.     In the algae cultivation apparatus that floats on the sea described in claims 1, 2, 3, and 4, the buoyancy of the apparatus can be increased by adjusting the length of the apparatus along the wave motion line.     The algae cultivation apparatus floated on the sea described in claims 1, 2, 3, 4, and 5 includes a fixed base portion and a seedbed (water storage portion) of algae.     In the algae cultivation apparatus which floats on the sea described in claims 1, 2, 3, 4, 5 and 6, carbon dioxide is supplied to the water storage unit as algae fertilizer. The method of cultivating algae with a device that floats on the sea is as follows.
The aquatic algae are separated from the surrounding seawater by the reservoir; the reservoir is continuously moved so that the algae is exposed to sunlight by levitating the reservoir at a level different from the wave motion and the sea level; The algae is poured from the base to the water reservoir at low tide.

Images