JPH11343181A - Production of porous formed body, culture method, culture system and filtration system using the same porous body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of porous formed bodies capable of being widely used, for example, as formed bodies for water treatment or as a nutrient supply medium for the culture of aquatic organisms by floating the bodies on the surface of water, where the production method comprises mixing coal ash or incineration ash with cement to obtain a mixture and forming the mixture into porous formed bodies each having a large specific surface area, and also to provide an organism culture method, an organism culture system and a filtration system, each for use in an open system using the porous formed bodies. SOLUTION: The production method comprises: adding a hardening material, a weight-lightening material, water, or the like, to a powdery material contg. inorganic matter such as coal ash or incineration ash to mix then together and to obtain a mixture; forming the mixture into porous formed bodies; and curing the formed bodies to from the objective porous formed bodies. By depositing required substances for marine organisms on each of the porous formed bodies and placing the resulting formed bodies in the sea, the culture of marine organisms is performed, and further, the filtration of sea water, or the like, can be performed by using the porous formed bodies.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a porous compact useful for improving the global environment, using coal ash generated from a coal-fired power plant or incineration ash generated from an incinerator.

[0002] The present invention also relates to a method and a system for culturing an organism using the porous molded body.
A culturing method and a culturing system capable of cultivating a large amount of algae and the like that can be used as immobilization of CO ₂ for preventing global warming, renewable energy resources and raw materials of food, and the porous molded body And a filtration system using the same.

[0003]

2. Description of the Related Art Coal-fired power plants in Japan emit millions of tons of coal ash annually, and about half of them are effectively used as raw materials for cement, but the rest is landfilled without being used effectively. Have been. Coal ash is a fine powder mainly composed of silica and alumina, and its components and properties are relatively stable, and there are few harmful components, so that it is suitable for effective use among wastes. For this reason, the expansion of the use is strongly desired.

[0004] In spite of the fact that the amount of incinerated ash generated is equal to that of coal ash, unlike coal ash, its effective use has not been made much yet and it has been disposed of in landfill. It is becoming difficult to secure landfill sites. Recently, however, the technology for separating and collecting garbage and detoxifying incineration ash has been rapidly advancing, and as a result, the components and properties of incineration ash have been stabilized, and the conditions for effective use have been gradually being prepared. There is something to note. This has opened up new prospects for the effective use of incinerated ash.

[0005] For effective utilization of coal ash, cement is mixed with coal ash to form a porous body, and pellets for water treatment are produced (Japanese Patent Laid-Open No. 8-243578). And gypsum are mixed and molded to be used for desulfurization of exhaust gas from thermal power plants (Japanese Patent Laid-Open No.
Publication No. 1-209038) has already been proposed.

[0006] On the other hand, global warming and accompanying food shortages,
The lack of energy due to the depletion of fossil fuels has been raised as a serious problem that threatens the existence of living things on earth, including humans, and measures are urgently needed for the next century.

[0007] As one of the measures against the above-mentioned problem, a method has been studied in which CO ₂ is immobilized on algae having high photosynthetic ability and fuels such as ethanol, and useful substances such as food and feed are produced from the algae. Have been. However, sunlight, which supplies the energy required for the growth of algae, has a large amount of CO2 due to the low energy density on the earth.
_A large area is required to fix ₂ . According to estimates, currently, in order to immobilize the algae all CO ₂ occurring in Japan, it is necessary to vast areas of even 1000km square. Since it is obviously difficult to secure such a vast area on land, the vast ocean has been attracting attention as a place for culturing algae. Unfortunately, large-scale cultivation in the ocean has the disadvantage that the supply of nutrients is costly, and therefore, in Japan, research has been limited to installing photoreactors on land.

[0008] Also, recently, a study of sprinkling iron in the nitrate-rich region,-a timely growth of microalgae, has attracted attention. In this study, too, the spread of iron is rapidly increasing in the ocean. It has been pointed out that there are many problems in practical use, such as the need to continuously spray iron in order to constantly culture microalgae. In order to culture algae in large quantities in the ocean, it is necessary not only to supply solar energy to the algae, but also to simultaneously supply nutrients and other substances required by the algae. However, when substances such as nutrients required by algae are sprayed into the ocean, many substances diffuse into the ocean without being used by the algae, so that a large amount of algae cannot be obtained in the ocean. was there.

[0009] In addition, substances not used in algae may diffuse into the ocean and cause abnormal growth of other microorganisms, and in some cases, destruction of the environment such as red tide cannot be ruled out. There were also problems.

[0010]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned prior art. First, in order to effectively utilize inorganic materials such as coal ash and incinerated ash discharged in large quantities. And a method for producing a porous molded body that can be supplied in large quantities.

[0011] By using the porous molded body supplied in a large amount, a substance required by living organisms in fresh water or seawater can be efficiently supplied and cultured on a vast water surface on a large scale. In addition, the present invention provides a method and system for culturing aquatic organisms without destroying the environment.

In addition, a filtration system for filtering cultured aquatic organisms and other suspended matters using the porous molded body is provided.

[0013]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, they have achieved the solution by the following method.

According to the method for producing a porous molded body of the present invention, an alkaline mixture is obtained by adding at least one of a hardening material and a lightening material and water to a powdery material containing an inorganic material and mixing. And a step of forming the alkaline mixture into a porous molded body, and a step of curing the molded body.

Further, the method for producing a porous molded article according to the present invention comprises:
A step of adding and mixing at least a curing material, a weight-reducing material, a phosphorus compound, and water to a powdery material containing an inorganic material to obtain an alkaline mixture, and a step of molding the alkaline mixture into a porous molded body. , And a step of curing the molded body.

Further, the method for producing a porous molded article according to the present invention comprises:
Adding and mixing at least a hardening material, a lightening material, an aquatic organism culture nutrient, a water repellent, and water to a powdery material containing an inorganic material to obtain an alkaline mixture, and forming the alkaline mixture into a porous material. And a step of curing the compact, wherein the density of the porous compact is 1.1 g.
/ Cm ³ or less.

The method for producing a porous molded article according to the present invention may include a step of immersing the porous molded article in an aqueous solution having a lower pH than that of the porous molded article to lower the pH value of the porous molded article. preferable.

In the method for producing a porous compact according to the present invention, it is preferable that at least one of coal ash and incineration ash is contained as the inorganic powdery material. In the method for producing a porous molded body of the present invention,
It is preferable to include at least one of cement and water glass as a hardening material.

In the method for producing a porous molded article of the present invention, it is preferable that at least one of pearlite and shirasu is included as a weight-reducing material.

In the method for producing a porous molded article of the present invention, as an alkaline mixture, 5 to 30 parts by weight of a hardening material and 5 to 5 parts by weight of a lightening material are added to 100 parts by weight of an inorganic powdery material. 30 to 100 parts by weight and 30 to 100 parts by weight of water
It is preferable to mix by weight. Further, in the method for producing a porous molded body of the present invention, as an alkaline mixture, 5 to 30 parts by weight of a hardening material and 5 to 40 parts by weight of a lightening material based on 100 parts by weight of a powdery material containing an inorganic substance. Parts, 5 to 20 parts by weight of a phosphorus compound, 2 to 20 parts by weight of a water repellent, and 30 to 100 parts by weight of water.

In the method for producing a porous molded article of the present invention, the curing of the porous molded article is preferably a heat treatment at 100 ° C. or higher.

In the method for producing a porous molded body of the present invention, the curing of the porous molded body is preferably performed by a heat treatment at 100 ° C.

In the method for producing a porous molded body according to the present invention, the curing of the porous molded body is preferably a heat treatment in steam at 100 ° C. or higher.

In the method for producing a porous molded article of the present invention, the porous molded article is immersed in an aqueous solution having a lower pH than that of the porous molded article, and the pH value of the porous molded article is adjusted to pH 4 to 9.
It is preferable to adjust to.

In the method for producing a porous molded article according to the present invention, the porous molded article is dipped into
It is preferable to use an aqueous solution containing phosphoric acid as the low pH aqueous solution that lowers the H value.

In the method for producing a porous molded article of the present invention, the porous molded article is maintained at a pressure lower than the atmosphere before being immersed in an aqueous solution having a lower pH than that of the porous molded article. It is preferable to perform deaeration of the compact.

In the method for producing a porous molded body of the present invention, it is preferable that the porous molded body is immersed in an aqueous solution having a lower pH than that of the porous molded body at a pressure higher than the atmospheric pressure. Further, in the method for producing a porous molded body of the present invention, it is preferable that a wet aquatic species be attached to the porous molded body and then dried.

Further, in the method for producing a porous molded article of the present invention, it is preferable that the porous molded article is dried and then a dried aquatic species is attached thereto.

As the powdery material containing an inorganic substance in the present invention, coal ash generated in a thermal power plant can be suitably used. Since coal ash is mostly fine powder fly ash and contains a large amount of calcium for desulfurization,
It is advantageous to react with phosphate ions to form a water-insoluble calcium phosphate salt. On the other hand, waste incineration ash has been rapidly improved in quality, including no harmful substances, due to the separate collection of waste and the technology for detoxifying incineration ash, and has become suitable for use.

As the hardening material in the present invention, cement, water glass or a mixture thereof can be used. Among them, various cements such as Portland cement can be used as cement, and the use rate of coal ash can be increased by using cement using coal ash for cement. As the water glass, sodium, potassium, lithium or a silicate compound containing an alkali metal of a mixture thereof, or sol-like silica can be used alone or in combination.

The weight-reducing material of the present invention is made porous by adding it, has a large specific surface area, and has a hollow portion therein to reduce the weight of the molded article.

As the lightening material of the present invention, pearlite and shirasu can be used. Shirasu is a sediment of light-weight volcanic ejecta such as pumice, and pearlite is a substance with a hollow spherical shell inside, as inferred from its origin in pearlite. Raw materials having the same composition as rocks can be manufactured artificially by crushing, firing and expanding.

As the lightening material, an organic material having pores or pumice can be used. Also, various types of foam materials can be used.

As a nutrient for aquatic organism culture used in the present invention, a nutrient containing phosphorus is preferably used. This is because algae need phosphorus content to proliferate, and its supply is desired in the ocean. For example, aluminum phosphate, sodium phosphate, and the like can be used alone or in combination.

The type of the water repellent used in the present invention is not particularly limited. For example, a silicone resin can be suitably used. In particular, a water-soluble silicone resin is suitable to be used by being added to a mixture such as coal ash.

In the method for producing a porous molded article of the present invention, depending on the use of the porous molded article, activated carbon powder, adsorbed components such as titanium oxide, silver, copper, catechin, etc., and a bactericidal component may be mixed. Or can be applied after molding.

In the method for producing a porous molded body of the present invention, 5 to 30 parts by weight of a curing agent is added to 100 parts by weight of a powdery material containing an inorganic material as an alkaline mixture. If the amount of the hardening material is less than 5 parts by weight, the strength of the molded body is insufficient. If the amount is more than 5 parts by weight, the ratio of the powdery material containing an inorganic substance such as coal ash becomes small, which is disadvantageous in terms of effective utilization. Also, 5 to 40 parts by weight of a lightening material is used. If the weight-reducing material is less than 5 parts by weight, it cannot be made porous and the specific surface area cannot be increased. If the weight-reducing material is more than 40 parts by weight, the ratio of the powdery material containing an inorganic substance such as coal ash also becomes small in this case, which is disadvantageous in terms of effective utilization.

When the lightening material is used in a state of being floated on the water surface in an amount of 5 to 40 parts by weight, more preferably 10 to 40 parts by weight is added. In this case, if the weight-reducing material is less than 5 parts by weight, the specific surface area cannot be increased due to porosity. In addition, it cannot float. On the other hand, if the weight-reducing material is more than 40 parts by weight, the ratio of the powdery material containing an inorganic substance such as coal ash becomes small, which is disadvantageous in terms of effective utilization.
When the phosphorus compound is used, 5 to 20 parts by weight is added. If the phosphorus compound is less than this, nutrients are insufficient,
On the other hand, if it exceeds 20 parts by weight, a problem arises in the stability as a molded body. When floating using a water repellent, 2
-20 parts by weight, more preferably 5-20 parts by weight. If the amount of the water repellent is less than 2 parts by weight, there is a problem in assuring floating for a long time, and if the amount is more than 20 parts by weight, problems such as an increase in manufacturing cost arise.

Further, by mixing 30 to 100 parts by weight of water with the above mixture, it is possible to obtain a mixture which is appropriately moistened and suitable for molding and curing.

The mixing method and molding method used in the present invention are not particularly limited, and can be selected from known methods.

The method of curing the molded article in the present invention is not particularly limited, and a method of curing by raising the temperature in addition to normal temperature and normal pressure curing can be used. Especially 100 ° C
A good hardened state can be obtained by raising the temperature and curing in a steam at 100 ° C. or higher.

In the present invention, the porous molded body has an alkaline component, and the molded body is molded and cured under the alkalinity. The pH value of the porous molded body is lowered by neutralizing the aqueous solution with an aqueous solution having a lower pH value.
Can be 7. For this purpose, for example, an aqueous solution containing phosphoric acid can be used. By using the aqueous solution containing phosphoric acid, the phosphoric acid binds to the calcium of the molded body to form a calcium salt of phosphoric acid, which is hardly soluble in water, in the molded body, and is adjusted to pH 4 to 9, or more preferably to pH 5 to 7. can do.

Here, the pH value of the porous molded body is defined as
600 g of the porous molded body is immersed in 1 liter of pure water, and is defined by an equilibrium value of pH reached by the water in which the porous molded body is immersed. (Viscosity Handbook 614, edited by The Viscosity Society of Japan
６page 615 according to the description of the method for measuring the pH of viscosity. In addition, when the pH of the porous molded body is reduced by an aqueous solution having acidity, the porous molded body is previously degassed under reduced pressure, for example, at 70 kPa or less, more preferably at 10 kPa or less, to thereby deaerate the porous molded body. The acidic aqueous solution can be well penetrated into the porous molded body. Further, the acidic aqueous solution is 0.11 MPa or more, more preferably 0.2 MPa
By immersing the porous molded body in the state where the pressure is increased to the above pressure, the aqueous solution can be sufficiently penetrated into the porous molded body. These treatments are particularly effective when a water repellent is used in the porous molded body.

The size of the porous molded body produced in the present invention is not particularly limited, and can be appropriately selected depending on its use, use environment, and use environment.

When the porous compact produced by the production method of the present invention is used as a nutrient supply medium for culturing aquatic organisms, aquatic organisms such as algae are attached thereto in advance, so that aquatic organisms can be recovered later. There is no need to spray seeds, which is convenient. As a method of attaching the aquatic organisms, a method of drying after attaching a wet aquatic organism to the porous molded body, or a method of attaching the species of the dried aquatic organism after drying the porous molded body. A method can be used.

Next, the operation of the present invention will be described.

In the present invention, a mixture containing a hardening material or a weight-reducing material and water is formed from an inorganic substance such as coal ash in an alkaline state and cured, so that the solidification proceeds due to the reaction, resulting in a porous and large specific surface area. A molded article can be obtained. And since this porous molded object has a large specific surface area, its adsorption area is large and many uses are possible.

If a water repellent is added to this porous molded body together with the weight-reducing material, it is advantageous for floating the water stably for a long time.

If the porous compact is neutralized with a solution containing phosphoric acid, for example, the calcium compact of phosphoric acid is deposited without dissolving or weakening the compact without dissolving or weakening the porous compact. Can be lowered. The porous molded body having a lowered pH value is suitable for, for example, a carrier for microorganisms or a nutrient supply medium for algae culture, and has a large adsorption area, so that it absorbs nutrients well and gradually dissolves out over a long period of time. Nutrients can be supplied to algae.

The culturing method according to the present invention comprises a step of supporting a substance required by the organism on a porous substance having a lower specific gravity than a solution in which the organism is present; Charging the solution and eluting the substance into the solution.

According to the culture method of the present invention, a substance required by an organism is supported on a porous substance having a lower specific gravity than a solution in which the organism is present, and the porous substance carrying the substance is introduced into the solution. Then, by eluting the substance into the solution, an optimal amount of the substance required by the organism can be supplied to the organism over a long period of time. Large-scale culture can be realized. Further, since a substance required by a living organism can be efficiently supplied to the living organism, it is possible to substantially prevent the destruction of the environment even when applied to an open system.

Further, the culturing method according to the present invention comprises the steps of: allowing a porous body having a lower specific gravity than a solution to carry a living organism and a substance required by the living organism in the solution;
Charging the porous body supporting the organism and the substance into the solution, releasing the organism into the solution, and eluting the substance.

According to the culturing method of the present invention, an organism capable of surviving in the solution and a substance required by the organism are supported on the porous body having a specific gravity smaller than that of the solution, and the organism and the substance are deposited on the porous body. The loaded porous body is put into a solution, the organism is released into the solution, and the substance is eluted, so that the organism released into the solution requires the organism. Since the optimal amount of the substance can be supplied over a long period of time, it is possible to realize large-scale culture of the organism in a solution in which the organism does not exist or the organism is not the predominant species. Further, since a substance required by a living organism can be efficiently supplied to the living organism, it is possible to substantially prevent the destruction of the environment even when applied to an open system.

Further, the culturing method according to the present invention comprises a step of supporting a substance required by living organisms living in the ocean on a porous body having a specific gravity lower than that of seawater, and a step of supporting the porous body carrying the substance. Introducing the substance into the ocean and eluting the substance into the ocean.

According to the culture method of the present invention, a substance required by living organisms living in the ocean is supported on the porous body having a specific gravity lower than that of seawater, and the porous body supporting the substance is mounted on the ocean. By introducing the substance into the ocean to elute it, an optimal amount of the substance required by the organism can be supplied to living organisms in the ocean over a long period of time. It is possible to realize mass culture of the body. In addition, since a substance required by an organism can be efficiently supplied to the organism, it is possible to substantially prevent marine environmental destruction. A substance required by living organisms to be eluted in the ocean, and a porous body having a smaller specific gravity than seawater constituting the ocean; and a means for introducing the porous body into the ocean. Features.

According to the culture system of the present invention, a porous body having a specific gravity smaller than that of seawater constituting the ocean, carrying a substance required by living organisms living in the ocean so as to be eluted in the ocean, Means for introducing the porous body into the ocean, whereby the porous body is introduced into the ocean and the optimum amount of the substance required by the organism in the ocean is provided for a long time. In the ocean,
It is possible to realize mass culture of the organism. Further, since a substance required by a living organism can be efficiently supplied to the living organism, it is possible to substantially prevent the environmental destruction of the ocean. In the present invention, the solution is not particularly limited as long as it is a liquid having a composition that permits the existence of a living organism and enables self-reproduction, and includes, for example, artificial or natural seawater and inland water. And a culture solution applied to culture of various microorganisms, cells, embryos and the like. Further, if necessary, a substance such as an antibiotic that suppresses the survival or growth of an organism other than the organism requiring culture is added to the solution to protect the organism requiring culture and enhance the culture efficiency. You can also. Also, the temperature of the solution,
The hydrogen ion concentration, the composition and partial pressure of the dissolved gas, the light conditions, and the like may be appropriately selected in consideration of the living conditions of the organism to be cultured.

Here, the organism refers to a living organism having self-reproduction as a basic attribute and having characteristics such as cell structure, regulation, substance metabolism, and repair ability. Examples of such organisms include various viruses, microorganisms, plants, animals, embryos, plant cells, animal cells, and the like. As described above, fuels such as ethanol, food and feed From the viewpoint that useful substances such as the above can be produced, for example, algae excellent in photosynthetic ability, in particular, plants that undergo autotrophic life represented by microalgae and the like can be preferably mentioned. Algae can be defined as those excluding embryonic plants from organisms that release oxygen in the process of photosynthesis. Brown algae, yellow green algae, hapto algae, rafid algae, Boqueria algae, euglena, prasino algae, green algae, axle algae and the like can be mentioned. In addition, as a living organism, a naturally occurring organism can be usually used, but various mutants can be used according to a request such as a purpose of use. further,
It is possible to use organisms that have been genetically modified by applying genetic engineering techniques.However, in this case, it is needless to say that sufficient confirmation is made so that there is no danger of destroying the ecosystem. Nor.

The porous body is not particularly limited as long as it supports the substance described below, has a specific gravity smaller than that of a solution such as seawater, and has a property of eluting the carried substance in the solution. Since mass production is possible at low cost, for example, activated carbon or coal ash that is currently being disposed of in large quantities and granulated with the main component can be suitably used. In addition, the porous body is a substance that adsorbs a substance required by the organism to be cultured from a solution such as seawater or inhibits the cultivation of the organism by itself in order to achieve highly efficient culture of the organism. It is also desirable to have such a property that does not elute into the solution. In light of this,
A relatively homogeneous fine powder mainly composed of silica and alumina, with few components harmful to living organisms and the environment such as heavy metals, and by taking measures such as coating the surface, adsorption and elution of the above components It is more desirable to use coal ash, which can substantially prevent the occurrence of the ash, as the porous body. The porous body produced using coal ash as one of the raw materials is
It can be easily formed by pressing or extrusion using a mold, and is easily available and economical because it is applied to, for example, an exhaust gas desulfurization device of a thermal power plant. . In addition, coal ash is currently disposed in landfills in the millions of tons annually, and has the advantage of helping to effectively use waste and extend the life of landfills. In addition, the particle diameter of the porous body, the diameter of the pores, the density of the pores, etc. are determined by the type of the organism to be cultured, the composition of the solution, the culture conditions, the substance carried on the porous body, and the solution of the substance. Is appropriately set according to the elution amount, elution rate, and the period in which elution of the substance should be observed. Also, the particle size of the porous body,
The pore diameter, pore density, and the like can be controlled so that the porous body sinks into the solution after a certain period of time, for example, by absorbing the solution. By configuring the porous body to settle in the solution after a certain period, even if the porous body is introduced over a wide area such as the ocean, the energy required for recovery of the porous body is suppressed. can do. In this case, the main component of the porous body is, for example, the above-mentioned coal ash, thereby substantially preventing pollution of the environment such as the ocean.

As a method of supporting a substance required by an organism on the porous body, for example, the porous body is immersed in a solution containing the substance, and after a certain period of time, the porous body is immersed in the solution. A method of removing the substance from the solution and drying it. In addition, when producing a porous body, a substance constituting the porous body and a substance required by an organism can be mixed, and the porous body can be produced from the mixture. At this time, when the substance to be supported on the porous body is a physiologically active substance such as a biocatalyst, a sufficiently careful operation is performed so that the physiological activity of the substance is not deactivated. If necessary, the substance required by the living organism may be encapsulated in a microcapsule or the like, or may be carried on another carrier, and may be carried on a porous body. Further, a plurality of substances required by living organisms may be supported on the porous body in combination. Further, in addition to the substances required by the organism, the porous body may further carry the organism, eggs and embryos of the organism, and the like. When the porous body is introduced into an open system such as the ocean, the organism to be cultured may not be the predominant species, and in such a case, the organism may not be cultured with high efficiency. . In addition, under an artificial environment such as a culture solution, there are many cases where no organism is present in the solution, and therefore, it is necessary to inoculate the solution with the organism. In addition to the substances required by the organism, the organism, eggs and embryos of the organism, and the like are further supported on the porous body, so that the above problem can be solved and the organism can be cultured with high efficiency. Becomes

Further, in order to elute the substance carried on the porous body from the porous body into the solution, the porous body is set and loaded with the substance as described above. It is sufficient to charge the solution. However, in order to control the amount and outflow rate of the substance eluted from the porous body, for example, a substance that generates a substance required by the organism is supported on the porous body, and the porous body is placed in a solution. After the introduction, a substance that reacts with the substance at a necessary time to produce a substance required by the organism may be introduced to generate a substance required by the organism in the solution. Since the porous body has a lower specific gravity than a solution such as seawater, when the substance carried on the porous body elutes into the solution, the substance is eluted from the surface layer of the solution. If the presence state in the vertical direction is confirmed in advance and controlled so that the optimal concentration of the substance reaches the region where the organism is present, not only the organism existing on the surface layer of the solution, It is quite possible to supply the substance to even the bottom organisms.

The substances required by living organisms include:
1) Acquisition of energy from food and sunlight. 2) Conversion of nutrients taken from outside into biological structural components and precursors for biopolymer synthesis. 3) Proteins using these constituents. Synthesis of various biological components such as nucleic acids and lipids,
4) Substances that act on metabolic activity for the purpose of synthesizing and decomposing various physiologically active substances required by cells and promote self-reproduction of organisms. And its precursors, and various physiologically active substances.

When culturing algae in the ocean, substances essential as nutrients necessary for the growth of the algae are nitrogen, phosphorus, potassium, and the like. Generally, potassium is present in a large amount in seawater. There is no need to supply again. Furthermore, since it is a component constituting chlorophyll and the like, iron is also required as a necessary nutrient for the growth of algae. Therefore, in this case, usually, the substances required by the living organisms are considered to be phosphorus and iron, and the substances are carried on the porous body and the porous body is introduced into the ocean. In addition, it is desirable that the above-mentioned phosphorus and iron are in a form easy to use for living organisms in a solution such as the sea, and may be in the form of various ions and complexes.

Further, the components constituting the organism such as algae can be adjusted by the culturing temperature or the substance to be given during the culturing. For example, when culturing algae, if nitrogen conditions are maintained at a general concentration, the ratio of the main constituent components of the algae is 20: 15: 6 as carbohydrate: fatty acid: protein.
It will be about 5. On the other hand, when only nitrogen is depleted under the above conditions, the ratio of the main constituent components of the algae is reduced to the carbohydrate:
Fatty acid: about 70:10:20 as protein,
If the nitrogen content is low during culturing, carbohydrate production tends to increase, and protein production tends to decrease. By the way, mass production of marine microorganisms, so-called red tide, is mainly caused by mass production of zooplankton due to excessive nitrogen and phosphorus in the coastal area. When a red tide occurs, the dissolved oxygen concentration decreases remarkably due to the respiration of zooplankton in the water area, and large quantities of fish and shellfish die. As described above, especially in algae, when the nitrogen content is low in the culture environment, the production of proteins is restricted, and the growth of zooplankton that feeds on the algae is suppressed. In addition, the suppression of the growth of zooplankton suppresses the consumption of oxygen in the ocean. Therefore, when the present invention is applied to an open system such as the ocean, the red tide can be suppressed by reducing the supply of nitrogen in the culture environment (in the ocean).

In particular, when algae are collected and stored temporarily, if the protein in the constituents of the algae is reduced, the amount of gas such as hydrogen sulfide and ammonia generated by the corrosion of the algae can be reduced. Is more suitable for preservation. Furthermore, when ethanol is produced from algae by fermentation, naturally, the production amount of ethanol increases as the amount of carbohydrate in the components of the algae increases.

Therefore, when culturing an organism, it is desirable to appropriately set the culturing conditions in accordance with the purpose of culturing the organism and the effect on the environment. For example, when a large amount of algae is cultured, the nitrogen content under the culturing conditions is generally reduced. It is preferable to limit. That is, when culturing algae, phosphorus and iron are mainly selected as substances supplied from the porous body, and nitrogen is kept to a minimum. In addition, some species of algae fix nitrogen.Even if the algae to be cultured do not have nitrogen-fixing ability, structural genes and regulatory genes related to nitrogen fixation are genetically engineered. Alternatively, it can be incorporated into algae having no nitrogen fixing ability, and in this case, it is not necessary to supply a new nitrogen component to the culture environment.

As a method for introducing a porous body carrying a substance required by an organism into a solution such as the ocean, for example, the porous body is continuously placed in a predetermined region constituting a surface layer of the solution. Alternatively, there may be mentioned a method of intermittently charging, or a method of continuously or intermittently charging the porous body to the entire surface portion of the solution. As a means for introducing a porous body carrying a substance required by an organism into a solution such as the ocean, a means for spraying from a moving body such as a ship, or a means for manually or a robot from a coastal area is used. Means can be mentioned. In addition, when the present invention is applied to culture of cultured cells or the like, a means for introducing a porous body into a culture solution using human power or a robot can be used. In any case, as long as the porous body is surely charged into the solution, the method of charging and the means for realizing the method are not limited at all.

Further, in the present invention, a means for shielding the sea area into which the porous body is charged so that living organisms are isolated in the sea area can be further provided. When culturing organisms such as algae in the ocean, the cultivated organisms are widely dissipated by ocean currents and diffusion, which not only makes recovery difficult, but also prevents the escape of organisms such as living waters and fishing waters. There is a possibility that it will spread to the sea area that should be. Therefore,
By providing a fence or the like around the sea area where an organism such as algae is cultured, the above possibility can be eliminated. The fence may be as simple as an oil fence, and the fence may be restrained to the seabed by, for example, an anchor so as not to be swept away by ocean currents or typhoons. In addition, organisms such as algae are not easily proliferated unless the above-mentioned substance is supplied by the porous body. Therefore, even if the organisms flow out of the fence, large-scale proliferation cannot occur.

In the present invention, the temperature, the hydrogen ion concentration, the composition of the dissolved gas, the amount of the dissolved gas, the composition of the solution, etc. of the solution in the ocean or the like are monitored during the cultivation, and if necessary, the biological Needless to say, by preparing a culture environment so that the metabolic activity of the body is maximized, it is possible to more reliably and efficiently culture the organism.

[0069] The filtration system of the present invention is characterized in that it has a step of filtering as a filtering material a porous body using freshwater or seawater containing plankton as a component of coal ash or incinerated ash as a raw material.

[0070] The filtration system of the present invention preferably has a step of dewatering the plankton and the filtering material after filtering fresh water or seawater containing plankton. Further, in the filtration system of the present invention, the microalgae are cultivated by suspending the microalgae in fresh water or seawater as a nutrient supply pellet using a porous body made of coal ash or incinerated ash as a raw material component, and then including the microalgae. Preferably, the method further includes a step of collecting the pellet and a step of filtering fresh water or seawater in which the microalgae are cultured using the pellet as a filtering material.

Further, the filtration system of the present invention is characterized in that as a means for separating a solid component from a liquid containing a solid component, a porous material made of coal ash or incinerated ash is used as a filter medium. .

As described above, in the present invention, the porous molded body using coal ash or incinerated ash as a raw material component can be used for cultivation of aquatic organisms, and the cultured aquatic organisms can be filtered to remove water. Can be used for a filtration system.

[0073]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be specifically described based on examples.

(Embodiment 1) A porous molded body was manufactured according to the manufacturing process shown in FIG. Using coal ash as an inorganic material, using sodium silicate or cement as a hardening material, using pearlite as a lightening material, mixing these with water, and extruding a machine with a diameter of 5 mm and a length of 5 m.
After molding to m, it was cured with steam at 120 ° C. for 24 hours, and then immersed in an aqueous sodium phosphate solution for 24 hours to adjust the pH.

FIG. 2 shows the relationship between the amount of the hardening material added and the compressive strength of the molded article in the porous molded article thus produced.
From Figure 2, the compressive strength with the amount of hardener is increased, when the desired compressive strength, etc. transportation and 10 kg / cm ² or more, to obtain the compressive strength 10 kg / cm ² or more, with respect to coal ash 100 parts by weight It can be seen that the addition amount of the curing agent needs to be 5 parts by weight or more.

FIG. 3 shows an example of the relationship between the amount of the lightening material added and the density and specific surface area of the molded article in the porous molded article thus produced.

FIG. 3 clearly shows that the specific surface area can be sharply increased by adding a lightening material. The specific surface area of the molded body can be increased by selecting the type and amount of other components in addition to the amount of the lightening material.

As described above, a porous molded body having a large specific surface area and suitable as a carrier for micro-organisms and a filter material could be produced.

(Embodiment 2) A porous molded body was manufactured according to the manufacturing process shown in FIG. Coal ash was selected as an inorganic material, and iron phosphate and a water-soluble silicone resin were added to the same hardening material and lightening material as in Embodiment 1 and mixed with water. 5m diameter
After molding to a length of 5 mm and a length of 5 mm, it was cured with steam at 120 ° C. for 24 hours. After drying, the molded body was immersed in an aqueous sodium phosphate solution for 24 hours to adjust the pH. FIG. 5 is an example of a diagram showing the relationship between the amount of the silicone resin, which is a water repellent, added to the porous molded body thus manufactured and the floating period in seawater. FIG. 5 clearly shows that the floating period is rapidly increased by the effect of the addition of the water repellent material. The floating period of the porous molded body can be extended by selecting the type and amount of other components such as a weight-reducing material in addition to the amount of the water-repellent material.

In this way, a porous molded body having a large non-surface area and suitable as a nutrient supply medium for culturing aquatic organisms such as microalgae could be produced. Then, it was confirmed that algae culture in the ocean was possible by attaching aquatic species such as algae to the porous molded body in advance, and then spraying the algae or the like on seawater.

(Embodiment 3) Next, an embodiment of the aquatic organism culturing method and the culturing system of the present invention will be described in detail.

As shown in FIG. 6, a 2 mx 2 mx 1 m concrete water tank 1 was filled with seawater 2 transported from the vicinity of Ogasawara. In the seawater 2, various microalgae were present at 0.1 g / L. Next, from the side wall of the water tank 1, 2
About 70 cm from the surface of seawater 2 at a distance of about 0 cm
An oil fence 4 covering up to a depth of m was laid, and an anchor 6 connected to a wire 5 was buried in the gravel 3 to fix the oil fence 4. Next, the activated carbon 7 carrying the phosphorus and iron compounds was introduced into the sea surface in the oil fence 4 to elute phosphorus and iron in the seawater 2. In addition,
The activated carbon 7 which is a porous body has its pore size and amount adjusted so as to float on the seawater 2, and the elution rate of the supported phosphorus and iron compounds is such that the optimal amount for the growth of microalgae is
It is controlled so that it always exists in the area where the microalgae inhabit the seawater 2. Here, the loading of the phosphorus and iron compounds on the activated carbon 7 was performed as follows. That is, 1
A 0% sodium phosphate-2% iron chloride aqueous solution was prepared, activated carbon was immersed in the aqueous solution, allowed to stand for 24 hours, pulled up again, and dried. Thus, activated carbon 7 supporting phosphorus and iron compounds was obtained. In addition, the water tank 1 is installed so that natural light is irradiated for an average of 5 hours a day, and the average water temperature of the seawater 2 is controlled to be 25 ° C.

FIG. 7 shows a growth curve of microalgae in seawater 2 in the water tank 1.

As shown in FIG. 7, in the present embodiment, the number of solids of the microalgae 8 was saturated in about 100 days.
At this time, a depth of 1 from the surface of the seawater 2 in the water tank 1
Within a range of up to 0 cm, the biomass of microalgae 8 is 5
g / L. Further, the microalgae 8 did not leak out of the oil fence 4 throughout the culture period.

From the above, it was confirmed that phosphorus and iron compounds were eluted from activated carbon 7 supporting phosphorus and iron compounds so as to be optimal for the growth of microalgae, and almost all of them were used for the growth of algae. . Also, from the analysis of seawater 2,
The amount of the eluted phosphorus and iron compounds diffusing into the seawater 2 without being used by the microalgae was small, and it was confirmed that these were efficiently used.

(Embodiment 4) Microalgae were cultured in exactly the same manner as in Embodiment 1 except that microalgae were supported on activated carbon 7 together with phosphorus and iron compounds.

FIG. 8 shows a growth curve of microalgae in seawater 2 in water tank 1.

As shown in FIG. 8, in the present embodiment, the number of solids of the microalgae 8 was saturated in about 80 days. At this time, a depth of 10 from the surface of the seawater 2 in the water tank 1.
cm, the biomass of the microalgae 8 reached 5 g / L, which is the same as in the first embodiment. Further, the microalgae 8 did not leak out of the oil fence 4 throughout the culture period.

From the above, it was confirmed that phosphorus and iron compounds were eluted from activated carbon 7 carrying phosphorus and iron compounds so as to be optimal for the growth of microalgae, and almost all of them were utilized for the growth of algae. . Also, from the analysis of seawater 2,
The amount of the eluted phosphorus and iron compounds diffusing into the seawater 2 without being used by the microalgae was small, and it was confirmed that these were efficiently used. Furthermore, since the activated carbon 7 carried the microalgae in the seawater, the period required for the biomass of the microalgae to saturate in the seawater could be shortened.

(Embodiment 5) Microalgae were cultured in exactly the same manner as in Embodiment 1 except that a porous body mainly composed of coal ash was used instead of the activated carbon 7.
Here, after the porous body is put into seawater,
It is configured to sink in seawater in about 05 days.
The seawater enters into the porous body with the passage of time in the porous body, but it goes without saying that the time to settling can be arbitrarily set by adjusting the size and amount of the void. In the present embodiment, the time from charging the porous body to seawater until the porous body settles,
It was set slightly longer than the time until the biomass of the microalgae was saturated. Thereby, the microalgae can be collected in a state where the porous body has settled in seawater, and there is no need to collect the porous body together with the microalgae, so that efficient collection of the microalgae can be expected.

In the present embodiment, the growth curve of the microalgae in the seawater 2 in the water tank 1 draws almost the same curve as in the first embodiment, and the number of solids of the microalgae 8 is saturated in about 100 days. . At this time, the biomass of the microalgae 8 reached 5 g / L as in the first embodiment within a range from the surface of the seawater 2 to a depth of 10 cm in the water tank 1. Further, the microalgae 8 did not leak out of the oil fence 4 throughout the culture period. Furthermore, the porous body settled in the seawater 2 105 days after charging the porous body in the seawater 2. In addition, the porous body was allowed to settle for one year, and the elution of heavy metals from the porous body was confirmed. However, the elution was not observed.

From the above, it was confirmed that the phosphorus and iron compounds were eluted from the porous body carrying the phosphorus and iron compounds so as to be optimal for the growth of microalgae, and almost all of them were utilized for the growth of algae. Was. Also, from the analysis of seawater 2,
The amount of the eluted phosphorus and iron compounds diffusing into the seawater 2 without being used by the microalgae was small, and it was confirmed that these were efficiently used. Furthermore, since contamination due to the porous body is prevented, and the porous body does not need to be recovered from the seawater together with the microalgae, it is possible to avoid a decrease in the economical efficiency required for the recovery of the porous body, and to efficiently reduce the cost. It was confirmed that a fine algae could be recovered.

(Embodiment 6) Next, an embodiment according to the filtration system of the present invention will be described in detail. FIG. 9 shows an embodiment of the filtration system of the present invention. The microalgae 41 shown in FIG. 9 is attached to or around a nutrient supply pellet 43 made of coal ash that can be suspended in seawater 42. Cultured. The recovery boat 44 is provided with a microalgae recovery device 45, and recovers microalgae and nutrient supply pellets together with seawater into the recovery boat 44 by a vacuum transport pump 46.

The recovery boat 44 is provided with a mesh-shaped plate 47 through which the nutrient supply pellets 43 do not pass, on which the nutrient supply pellets are accumulated. Microalgae are filtered by nutrient feed pellets. The seawater passes through the drain pipe 49 and is discharged outboard by the drain pump 10. The filtered microalgae and the nutrient supply pellets are conveyed to the rotary crushing and dewatering machine 11 by the crane 48, crushed and dewatered, and stored as powder 12.

(Embodiment 7) Another embodiment of the filtration system of the present invention will be described with reference to FIGS.

FIG. 10 is a view showing a coal storage effluent treatment and filtration device installed in a coal-fired power plant. In FIG. 10, raw water 20 containing coal powder enters a filter device 21 from a valve 23 by a pump 29 and is filtered by a filter medium 22.
The treated water 30 is discharged from the valve 24. As the filtering material 22, a porous pellet having coal ash as a raw material is used.
Since the filter material is inexpensive and can be supplied in large quantities, when the pressure difference between the inlet and outlet of the filter rises, a certain amount is withdrawn from the valve 27 and replenished from the valve 28. Since the extracted filter material and sludge mainly consist of coal dust and coal ash, there is no problem if they are returned to the coal storage as they are.

Here, when it is desired to reduce the amount of the filter medium to be replaced, a backwashing step may be added as shown in FIG.
At the time of backwashing, backwash water 31 is supplied from a valve 26, and the captured coal powder is washed away from the filter material.
2 is discharged.

FIGS. 10 and 11 show the coal storage yard.
The same applies to other filtration devices such as sewage treatment plants. in this case,
There is no danger of emission of harmful substances even if the extracted filter media is incinerated.

[0099]

According to the present invention, a porous compact having a large specific surface area, such as activated carbon or zeolite, is mainly made of coal ash or incinerated ash which has not been used and is disposed of in large quantities at present. Can be manufactured. Therefore, in place of activated carbon and zeolite, it can be used as an absorbent used for deodorization, sterilization, removal of harmful substances, and as a carrier for immobilizing microorganisms used for sewage treatment, fermentation, soil recovery, and the like. Further, the porous molded body produced by the present invention can be used as a nutrient supply medium for aquatic organism culture by being suspended in water. By spraying this nutrient supply medium for aquatic organism culture into the ocean,
For example, algae can be grown and carbon dioxide in the atmosphere can be absorbed. For this reason, it is possible to contribute to the prevention of global warming by absorbing carbon dioxide gas in the atmosphere while preventing eutrophication of the ocean, and the grown algae can be used as a raw material for useful materials such as ethanol and other alternative fuels for fossil fuels.

Further, according to the culture method of the present invention, a substance required by an organism is supported on a porous substance having a lower specific gravity than a solution in which the organism is present, and the porous substance carrying the substance is dissolved in a solution. To elute the substance into the solution, the optimal amount of the substance required by the organism can be supplied to the organism over a long period of time. It is possible to provide a culture method by which a large amount of a body can be cultured. Further, it is possible to provide a culture method which can efficiently supply a substance required by an organism to the organism, so that even when applied to an open system, environmental destruction can be substantially prevented. Can be.

Further, according to the culturing method of the present invention, an organism capable of surviving in the solution and a substance required by the organism are supported on the porous material having a lower specific gravity than the solution, By pouring a porous body carrying a substance into a solution to release the organism in the solution, and elute the substance, the organism released into the solution is:
Since the optimal amount of the substance required by the organism can be supplied over a long period of time, large-scale culture of the organism can be realized in a solution in which the organism is absent or in which the organism is not the predominant species. Culturing method can be provided.
Further, it is possible to provide a culture method which can efficiently supply a substance required by an organism to the organism, so that even when applied to an open system, environmental destruction can be substantially prevented. Can be.

Further, according to the culture method of the present invention,
A substance required by living organisms living in the ocean is supported on a porous body having a specific gravity smaller than that of seawater, and the porous body supporting the substance is introduced into the ocean to elute the substance into the ocean. The present invention provides a culture method capable of realizing a large-scale cultivation of organisms in the ocean, because an optimal amount of a substance required by the organisms can be supplied to organisms in the ocean for a long period of time. be able to. Further, since a substance required by a living organism can be efficiently supplied to the living organism, it is possible to provide a culturing method capable of substantially preventing marine environmental destruction.

Further, according to the culture system of the present invention, a porous body which carries a substance required by living organisms living in the ocean so as to be eluted in the ocean, and has a specific gravity smaller than that of seawater constituting the ocean; Means for introducing the porous body into the ocean, the porous body is introduced into the ocean,
Provided is a cultivation system capable of realizing a large-scale cultivation of organisms in the ocean because an optimal amount of a substance required by the organisms can be supplied to the organisms in the ocean for a long time. Can be. Further, since a substance required by a living organism can be efficiently supplied to the living organism, it is possible to provide a culturing method capable of substantially preventing marine environmental destruction.

As is clear from the above, according to the present invention, it is possible to mass-cultivate organisms such as algae in the vast ocean while preventing the occurrence of red tide and the like, and to reduce global warming by fixing CO ₂ . It can greatly contribute to current global issues such as prevention, securing energy resources by manufacturing ethanol, and manufacturing food and feed.

Further, according to the filtration system of the present invention, even when microalgae are cultured on a large scale, they can be efficiently collected and transported at low cost. Further, not only can a filtration system used for wastewater treatment in a power plant or a sewage treatment plant be provided at a low cost, but also effective use of coal ash and incineration ash that are currently disposed in large quantities can be achieved.

[Brief description of the drawings]

FIG. 1 is a production process diagram showing an embodiment of a method for producing a porous molded article of the present invention.

FIG. 2 is a view showing the relationship between the amount of a hardening agent added and the compressive strength of a porous molded body in one embodiment of the method for producing a porous molded body of the present invention.

FIG. 3 is a diagram showing the relationship between the amount of a lightening material added and the density and specific surface area of a porous molded body in one embodiment of the method for producing a porous molded body of the present invention.

FIG. 4 is a manufacturing process diagram showing another embodiment of the method for manufacturing a porous formed body of the present invention.

FIG. 5 is a diagram showing the relationship between the amount of a water-repellent material added and the floating period of the porous molded body in seawater in one embodiment of the method for producing a porous molded body of the present invention.

FIG. 6 is a diagram showing a configuration according to an embodiment of the culture method of the present invention.

FIG. 7 is a diagram showing a growth curve of microalgae.

FIG. 8 is a diagram showing a growth curve of microalgae.

FIG. 9 is a diagram showing one embodiment of a filtration system of the present invention.

FIG. 10 is a view showing another embodiment of the filtration system of the present invention (when water is passed).

FIG. 11 is a view showing still another embodiment (at the time of backwashing) of the filtration system of the present invention.

[Explanation of symbols]

1 ... aquarium, 2 ... seawater, 3 ... gravel, 4
…… Oil fence, 5… Wire, 6… Anchor, 7… Activated carbon, 8 …… Microalgae, 10…
... drain pump 11 ... dehydrator 12 ... powder, 20 ... raw water, 21 ... filtration device,
22 ... filter material, 23-28 ... valve, 29 ...
... pump, 30 ... treated water, 31 ... backwash water, 32 ... sludge, 41 ... microalgae, 4
2 ... seawater 43 ... nutrient supply ぺ let 4
4 ... Recovery boat, 45 ... Recovery device, 46 ...
Pump, 47 ... mesh plate, 48 ... crane,
49 ... water pipe

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C04B 38/08 C12M 1/00 E C12M 1/00 1/12 1/12 C12N 1/00 A C12N 1/00 1/12 B 1/12 B09B 3/00 301M // (C04B 28/26 301S 14:18) (72) Inventor Yoshio Ishimori No. 1 Komukai Toshiba-cho, Saiwai-ku, Kawasaki-shi, Kanagawa Prefecture Toshiba R & D Center

Claims (31)

[Claims] 1. A step of adding at least one of a hardening material and a weight-reducing material to a powdery material containing an inorganic material and water to obtain an alkaline mixture, and forming the alkaline mixture into a porous material. A method for producing a porous molded body, comprising: a step of molding into a body; and a step of curing the molded body. 2. A step of adding and mixing at least a hardening material, a weight-reducing material, a phosphorus compound and water to a powdery material containing an inorganic material to obtain an alkaline mixture, and forming the alkaline mixture into a porous molded body. And a step of curing the molded article. 3. A step of adding and mixing at least a hardening material, a lightening material, aquatic organism culture nutrients, a water repellent and water to a powdery material containing an inorganic substance to obtain an alkaline mixture, Forming a porous molded body,
Curing the molded body. A method for producing a porous molded body having a density of 1.1 g / cm ³ or less, characterized by comprising a step of curing the molded body. 4. The porous molded body is immersed in an aqueous solution having a lower pH than that of the porous molded body, and
The method for producing a porous molded body according to any one of claims 1 to 3, further comprising a step of lowering the H value. 5. The porous compact according to claim 1, wherein the powdery material containing an inorganic material includes at least one of coal ash and incineration ash. Manufacturing method. 6. The method according to claim 1, wherein the hardening material contains at least one of cement and water glass.
A method for producing a porous molded article according to any one of claims 3 to 3. 7. The method according to claim 1, wherein the weight-saving material includes at least one of pearlite and shirasu. 8. The alkaline mixture is prepared by adding 5 to 30 parts of a curing agent to 100 parts by weight of a powdery material containing an inorganic substance.
Parts by weight, 5-40 parts by weight of lightening material and 30-1 parts of water
The method for producing a porous molded article according to any one of claims 1 to 3, characterized in that the composition is blended with 00 parts by weight. 9. The alkaline mixture is prepared by adding 5 to 30 parts of a curing agent to 100 parts by weight of a powdery material containing an inorganic substance.
Parts by weight, 5 to 40 parts by weight of lightening material, 5 to 5 parts by weight of phosphorus compound
20 parts by weight, 2 to 20 parts by weight of water repellent and 30 to 30 parts by weight of water
The method for producing a porous molded article according to any one of claims 1 to 3, wherein 100 parts by weight are blended. 10. The curing of the porous molded body is performed at 100 ° C.
The method for producing a porous molded body according to any one of claims 1 to 3, wherein the heat treatment is performed as described above. 11. The curing of the porous molded body is performed at 100 ° C.
The method for producing a porous molded body according to any one of claims 1 to 3, wherein the heat treatment is performed. 12. The method according to claim 1, wherein the curing of the porous molded body is a heat treatment in steam at 100 ° C. or higher.
A method for producing a porous molded article according to any one of claims 3 to 3. 13. The porous molded body is immersed in an aqueous solution having a lower pH than that of the porous molded body to adjust the pH value of the porous molded body to pH 4-9. A method for producing the porous molded article according to the above. 14. The porous molding according to claim 4, wherein an aqueous solution containing phosphoric acid is used as the low pH aqueous solution for lowering the pH value of the porous molding by immersing the porous molding. How to make the body. 15. Deaeration of the porous compact by maintaining the porous compact at a pressure lower than the atmosphere before immersing the porous compact in an aqueous solution having a lower pH than the porous compact. The method for producing a porous molded article according to claim 4, characterized in that: 16. The method for producing a porous molded article according to claim 4, wherein the porous molded article is immersed in an aqueous solution having a lower pH than that of the porous molded article at a pressure higher than the atmospheric pressure. . 17. The method for producing a porous molded body according to claim 2, wherein a wet aquatic species is attached to the porous molded body and then dried. 18. The method for producing a porous molded article according to claim 2, wherein the porous molded article is dried and then a dried aquatic species is attached thereto. 19. A step of supporting a substance required by the organism on a porous body having a smaller specific gravity than a solution in which the organism is present; and charging the porous body carrying the substance into the solution, A step of eluting the substance into the solution. 20. A step of supporting a living organism and a substance required by the living organism in the solution on a porous body having a lower specific gravity than the solution; and a porous body supporting the living organism and the substance. Charging the solution into the solution to release the organism into the solution and elute the substance. 21. A step of supporting a substance required by living organisms living in the ocean on a porous body having a specific gravity smaller than that of seawater, and introducing the porous body supporting the substance into the ocean, A step of eluting the substance therein. 22. The culture method according to claim 19, wherein the substance is at least one substance selected from a phosphorus compound and an iron compound. 23. The culture method according to claim 19, wherein the porous body contains coal ash as a constituent. 24. The culture method according to claim 21, wherein the porous body is adjusted to absorb the seawater and settle in the ocean. 25. The culture method according to claim 21, wherein the organism is a microalga. 26. A substance that is required by living organisms living in the ocean to be carried out so as to be eluted in the ocean, and a porous body having a specific gravity smaller than seawater constituting the ocean; A culture system, comprising: 27. The culture system according to claim 26, further comprising means for shielding a sea area into which the porous body has been put so that the living organisms are isolated in the sea area. 28. A filtration system comprising a step of filtering as a filtering material a porous body using freshwater or seawater containing plankton as a component of coal ash or incinerated ash as a raw material. 29. The filtration system according to claim 28, further comprising a step of dehydrating a plankton and a filtering material after filtering fresh water or seawater containing plankton. 30. A microalgae is cultivated by suspending the microalgae in fresh water or seawater using a porous body made of coal ash or incinerated ash as a raw material as a nutrient supply pellet, and then removing the pellet containing the microalgae. 29. The method according to claim 28, further comprising a step of collecting and filtering fresh water or seawater obtained by culturing the microalgae using the pellet as a filtering material.
Or a filtration system according to claim 29. 31. A filtration system characterized by using a porous medium made of coal ash or incinerated ash as a raw material as means for separating a solid component from a liquid containing the solid component.