Biomass energy conversion system and biomass energy conversion method

Abstract

To provide a biomass energy conversion system and a biomass energy conversion method that efficiently deliver a stable humus liquid containing iron fulvate to organisms while reducing the amount of carbon dioxide emissions.SOLUTION: A biomass energy conversion system comprises a biochar production part 3 that carbonizes biomass feedstock to produce charcoal raw material and extracts a wood vinegar 11 from a carbonization gas 32 by removing impurities, an ironmaking part 6 that uses the raw material in a blast furnace, a gas extraction part that extracts carbon dioxide 30 from exhaust gas discharged from the ironmaking part 6, and a humus liquid production part comprising a first production part 41 that produces a humus liquid 12 by immersing an organic matter 40 in the wood vinegar 11, a second production part 42 that produces the gas-containing humus liquid 13 by dissolving the carbon dioxide 30 in the humus liquid 12, and a third production part 43 that produces an iron-containing humus liquid 14 by immersing a steel slag 61 produced by the ironmaking part 6 in the gas-containing humus liquid 13.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a biomass energy conversion system and a biomass energy conversion method, and more particularly to a biomass energy conversion system and a biomass energy conversion method using a humic solution containing fulvic acid. [Background technology]

[0002] In the natural world, plant matter such as fallen leaves and fallen trees accumulate, and humus is produced by the fermentation and decomposition process involving microorganisms and fungi. Humus is fractionated by alkali and acid, and the alkali-soluble and acid-soluble fractions are called fulvic acid. Fulvic acid contains a large amount of carboxyl groups, a complexing agent with strong chelating properties, which combine with iron (ionized divalent iron) dissolved in water in the anoxic conditions of the soil to become fulvic acid iron, a water-soluble substance formed by the chelation of fulvic acid and divalent iron ions, producing iron-containing humic matter. Iron fulvic acid dissolved from iron-containing humic matter is carried to the sea by rivers and contributes to the growth of phytoplankton and seaweed.

[0003] In nature, fulvic acid iron is produced by the combination of humus and divalent iron ions, but because it is largely dependent on chance, it is in short supply in some areas and is thought to be the cause of sludge in rivers and the devastation of marine resources. Attempts have been made to artificially produce fulvic acid iron in the ocean, but a huge amount of divalent iron ions is required to improve the environment, making this a difficult situation. In Patent Documents 1 and 2, in order to produce humus containing fulvic acid iron, iron or a substance containing iron is added to the fermentation and decomposition process of organic waste, and artificial fulvic acid-containing humus is produced.

[0004] In recent years, with the rise in environmental awareness due to the SDGs and other initiatives, efforts are being made to reduce greenhouse gas carbon dioxide emissions. In Japan, too, a target has been set of reducing carbon dioxide emissions by 46% by 2030 as a gradual carbon neutral goal, but the steel industry accounts for 15% of domestic carbon dioxide emissions and approximately 40% of carbon dioxide emissions in the industrial sector. This is due to carbon dioxide generated by the operation of blast furnaces and converters that rely on fossil fuels, and by chemical reactions when making steel. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2012-254450 A [Patent Document 2] Patent No. 5864811 Summary of the Invention [Problem to be solved by the invention]

[0006] Here, even if ferrous iron ions that can be ingested by photosynthetic organisms are eluted by humus, the ferrous iron ions are easily oxidized by oxygen in the water, becoming ferrous iron ions, which immediately settle as solid iron and become impossible for organisms to ingest. Therefore, it is difficult to say that conventional techniques are efficient in supplying ferrous iron ions to organisms. If iron is to be supplied to an aquatic or soil environment, it is preferable to supply ferrous iron ions in a state in which they are difficult to oxidize, but it is difficult to say that the ferrous iron ions generated by conventional humus containing fulvic acid are difficult to oxidize.

[0007] In addition, in order to reduce carbon dioxide emissions in the steel industry, efforts are being made to replace part of the coal used in blast furnaces with hydrogen or methane, but these efforts are still in the experimental stage and have not yet reached the demonstration stage. Against this background, new measures to reduce carbon dioxide emissions were needed.

[0008] Therefore, an object of the present invention is to provide a biomass energy conversion system and a biomass energy conversion method that efficiently delivers humic solution containing stable iron fulvic acid to organisms while reducing carbon dioxide emissions. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention provides a biomass energy conversion system comprising a raw material production section that carbonizes biomass raw materials to produce raw materials and removes impurities from the dry distillation gas to extract wood vinegar, an ironmaking section that uses the raw materials produced from the raw material production section in a blast furnace or converter to obtain iron-containing materials, a gas extraction section that extracts a specific gas containing carbon dioxide from exhaust gas discharged from at least one of the raw material production section or the ironmaking section, a first generation section that produces a humus liquid containing fulvic acid by soaking organic matter in the wood vinegar, a second generation section that dissolves the specific gas extracted from the gas extraction section in the humus liquid to produce a gas-containing humus liquid, and a third generation section that soaks the iron-containing material in the gas-containing humus liquid to produce an iron-containing humus liquid.

[0010] In addition, it is preferable that the raw material production unit further has a coke production unit that compresses the biomass raw material to produce bio-coke, and the steelmaking unit uses the bio-coke as a raw material.

[0011] It is also preferable that the third generation unit has a tank for storing the gas-containing humus liquid and a mesh-like holding unit arranged within the tank, and that the iron-containing material is placed in the holding unit and immersed in the gas-containing humus liquid in the tank to generate iron-containing humus liquid.

[0012] It is also preferable that the present invention further includes a pH adjustment unit that adjusts the pH value of the iron-containing humus liquid generated by the third generation unit, and the pH adjustment unit adjusts the pH value of the iron-containing humus liquid based on the environment of the breeding unit.

[0013] Furthermore, the present invention provides a biomass energy conversion method comprising the steps of: carbonizing a biomass raw material in a pyrolysis furnace to produce a raw material and obtain a dry distillation gas; removing impurities from the dry distillation gas to extract wood vinegar; using the raw material in a steelmaking blast furnace to obtain an iron-containing substance; extracting a specific gas containing carbon dioxide from exhaust gas discharged from at least one of the blast furnace or the pyrolysis furnace; soaking an organic matter in the wood vinegar to produce a humus solution containing fulvic acid; dissolving the specific gas in the humus solution to produce a gas-containing humus solution; and soaking the iron-containing substance in the gas-containing humus solution to produce an iron-containing humus solution. Effect of the Invention

[0014] According to this configuration, the humus generating unit can generate iron-containing humus, and the iron-containing humus can be used in marine aquaculture or farmland, where the divalent fulvic acid iron contained in the iron-containing humus can be absorbed by living organisms, thereby reducing agricultural disease and creating fertile fields and realizing sea areas rich in marine life. In addition, the specific gases including carbon dioxide generated by the raw material producing unit and the steelmaking unit are extracted and dissolved in the humus in the second generating unit, so that the carbon dioxide emissions of the entire biomass energy conversion system can be reduced. Furthermore, the raw material producing unit produces raw materials for steelmaking from biomass raw materials, the raw materials are used in a blast furnace or converter in the steelmaking unit to obtain iron-containing substances, the second generating unit generates gas-containing humus in which the specific gases including carbon dioxide are dissolved from wood vinegar, and the third generating unit generates iron-containing humus by soaking the iron-containing substances, so that the biomass energy conversion system can be completed without discharging by-products, residues, etc. In addition, the iron-containing humus solution produced by this process can exist as divalent iron ions without immediately converting to trivalent iron ions and precipitating as solid iron, so that divalent iron ions can be efficiently supplied to living organisms. This makes it possible to simultaneously improve the energy conversion efficiency of the entire biomass energy conversion system and reduce the environmental load.

[0015] According to this configuration, bio-coke can be obtained by compressing biochar in the coke making section, and by using the bio-coke in the steel making section, it is possible to reduce carbon dioxide emissions by replacing fossil fuels. In addition, specific gases including carbon dioxide generated by the steel making section are extracted and dissolved in humus liquid in the second generation section, so that the carbon dioxide emissions of the entire biomass energy conversion system can be reduced.

[0016] According to this configuration, the third generation unit generates iron-containing humus liquid by placing an iron-containing material in the holding unit and immersing it in the gas-containing humus liquid in the tank, so that the iron-containing humus liquid can be generated by a simple method. In addition, the iron ions contained in the iron-containing material generated as a by-product or residue in the steelmaking unit are converted into divalent iron fulvic acid by the chelating agent contained in the humus liquid. The divalent iron fulvic acid generated by this process is in a stable state, so unlike conventional divalent iron fulvic acid, it is unlikely to change into trivalent iron fulvic acid due to oxidation. This makes it possible to stably deliver divalent iron fulvic acid to living organisms. Furthermore, the iron-containing material used in the third generation unit can be widely used as riverbed gravel, cement, ground improvement material, and civil engineering materials without the risk of oxidation because the iron ions are dissolved.

[0017] According to this configuration, the pH adjustment unit adjusts the pH value of the iron-containing humus liquid based on the breeding unit, so that the iron-containing humus liquid can be supplied while minimizing the environmental load on the breeding unit. Since the pH adjustment unit adjusts the pH value of the iron-containing humus liquid, the pH value is adjusted at the final stage of supplying the iron-containing humus liquid from the biomass energy conversion system to the breeding unit. If the pH value of the humus liquid were adjusted here, the pH value would change when it passes through the second or third generation unit. In contrast, in the biomass energy conversion system of this embodiment, the pH value of the iron-containing humus liquid supplied to the breeding unit is adjusted, so that the environmental load on the breeding unit can be suppressed.

[0018] According to the present invention, it is possible to provide a biomass energy conversion system and a biomass energy conversion method that efficiently deliver humic solution containing stable iron fulvic acid to organisms while reducing carbon dioxide emissions. [Brief description of the drawings]

[0019] [Figure 1] FIG. 2 is a flow diagram of the biomass energy conversion system of the present invention. [Diagram 2] FIG. 2 is a flow diagram showing the flow of materials in the biomass energy conversion system of the present invention. [Diagram 3] FIG. 2 is a block diagram of the humus liquid production section of the biomass energy conversion system of the present invention. [Figure 4] FIG. 2 is a diagram showing a third generation section of the biomass energy conversion system of the present invention. [Diagram 5] FIG. 2 is a diagram showing the measurement results of the total organic carbon amount in the iron-containing humus solution of the biomass energy conversion system of the present invention. [Figure 6] FIG. 8 is a diagram showing the production conditions for the samples of the iron-containing humus solution shown in FIG. 7 of the biomass energy conversion system of the present invention. [Figure 7] FIG. 7 is a diagram showing the organic carbon content of each sample of the iron-containing humus solution of the biomass energy conversion system of the present invention. [Figure 8] 1 is a table showing the iron ion concentration of the humus solution soaked with slag iron of the biomass energy conversion system of the present invention. [Figure 9] 1 is a table showing the iron ion concentration of the humus solution soaked with slag iron of the biomass energy conversion system of the present invention. [Figure 10] 1 is a table showing the iron ion concentration of the humus solution soaked with slag iron of the biomass energy conversion system of the present invention. [Figure 11] 1 is a flow chart of a biomass energy conversion system of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] A biomass energy conversion system 1 according to an embodiment of the present invention will be described with reference to Figs. 1 to 11. The biomass energy conversion system 1 is composed of a raw material production section 2, a biochar production section 3, a humus liquid production section 4, a coke production section 5, an iron making section 6, and a pH adjustment section 8. The biomass energy conversion system 1 improves the breeding environment by supplying the iron-containing humus liquid 14 produced by the humus liquid production section 4 to the breeding section 7. In the biomass energy conversion system 1, wood, pruning branches, herbaceous plants, lumber residues, agricultural crop residues, plant resources, agricultural waste, livestock manure, paper sludge, sewage sludge, and seaweed, which are biomass raw materials, can be used as raw materials. In this embodiment, since wood 10 is used as the biomass raw material, the yield of products obtained by pyrolysis is about 35% charcoal, about 30% wood vinegar, about 20% wood tar, and about 15% gas, and many by-products are generated other than charcoal. In the following explanation, wood vinegar is a concept that includes bamboo vinegar obtained from bamboo materials.

[0021] The raw material production section 2 has a cutter 21 and a dryer 22. The raw material wood 10 is cut into a predetermined shape by the cutter 21 to produce wood material 20, and fine dust is separated using a sieve. The dryer 22 uses a rotary dryer to continuously rotate at high speed to dry the wood material and evaporate a certain amount of moisture. The heat source for the dryer 22 is exhaust heat from the pyrolysis furnace 33 of the biochar production section 3. The dryer 22 may be a low-temperature belt dryer type that allows continuous drying at low cost, or a solar drying type that has a low environmental impact.

[0022] In the biochar production section 3, biochar 31 is obtained from the wood material 20, wood vinegar 11 is extracted from the dry distillation gas 32, and carbon dioxide 30 is separated and collected from the exhaust gas. Specifically, the biochar production section 3 has a pyrolysis furnace 33 that heats and steams the wood material 20 to gasify it by pyrolysis, and an extraction section 34 that extracts wood vinegar 11 from the dry distillation gas 32. In this embodiment, indirect heating gasification is performed by steaming at 200°C or higher under anaerobic conditions. Air is used as the gasification agent, but oxygen, hydrogen, water vapor, carbon dioxide, etc. may also be used. When carbon dioxide is used as the gasification agent, it is preferable to use carbon dioxide 30 recovered in the biochar production section 3 and the steelmaking section 6 and stored in a storage tank 47 described later. By semi-carbonizing biochar 31 at a temperature of 200°C or higher in the pyrolysis furnace 33, the ash content is lower compared to carbonized biomass by pyrolysis, and the weight loss rate is also reduced, so that a lot of energy is stored in the biochar 31. This allows high-energy bio-coke to be produced in the coke production section 5, and also allows it to replace fossil fuels in the steelmaking section 6. The temperature conditions in the pyrolysis furnace can be set as desired depending on the raw material and the application of the biochar 31, so the biochar 31 may be produced by pyrolysis at 350°C or higher.

[0023] The pyrolysis furnace 33 in the biochar production section 3 uses an externally heated rotary kiln furnace or a backdraft type, but may be any of a fixed bed furnace, a stoker furnace, a fluidized bed furnace, an internal circulation type fluidized bed boiler, an external circulation type fluidized bed boiler, or any other type of furnace. The external heating type does not directly burn the wood material 20, but steams it with heat from the outside, so no harmful substances such as dioxins are generated. In the pyrolysis furnace 33, the dried wood material 20 is placed in a heat-resistant steel reaction tube and heated while rotating to gasify it. This results in contact heat transfer, which increases the heat transfer coefficient and allows the wood material 20 to be efficiently gasified. In addition, since it is a horizontal agitation furnace, there are few restrictions on the shape of the raw material, and bark, bamboo, and other raw materials that are easily entangled in fibers can also be processed. The dry distillation gas 32 generated from the pyrolysis furnace 33 is sent to the extraction section 34, and biochar 31 is extracted from the floor of the pyrolysis furnace 33. In this embodiment, the wood material 20 is used as the raw material for the biochar 31, but it is not limited thereto, and carbonized materials effective for activating organisms and improving the environment, made from biological resources such as crop residues, can also be used. Specifically, materials derived from livestock manure, herbs, rice husks, rice straw, nuts, paper sludge, sewage sludge, seaweed, etc. can also be used for the biochar 31. The wood material 20 is an example of the biomass raw material of the present invention.

[0024] In the extraction section 34, the dry distillation gas 32 from the pyrolysis furnace 33 is cooled by spraying it with a liquid such as water, and the solids, such as biomass powder and charcoal powder, dispersed in the dry distillation gas 32, the wood vinegar 11, and liquid tar droplets are captured by this liquid and separated from the dry distillation gas 32. In the collector, the dry distillation gas 32 not containing the solids is separated from a slurry-like liquid containing the solids, and the wood vinegar 11 is extracted by gravity separation. A filter may be provided downstream of the collector to remove impurities from the dry distillation gas 32.

[0025] The pyrolysis furnace 33 and the extraction section 34 can utilize a system that indirectly supplies steam heat, including saturated steam and heated steam, generated by a superheated steam generator to the reaction tank, to pyrolyze the biomass raw material. For example, by using the organic waste treatment system described in Patent No. 7043673, the water content of the biomass raw material can be reduced by vaporizing the water content of the biomass raw material, since heating is performed from outside the reaction tank. In addition, condensation is unlikely to occur in the reaction tank, and steam heat is distributed throughout the reaction tank, allowing for uniform pyrolysis.

[0026] The carbonized gas 32 from which impurities have been removed by the collector and the filter may be mixed with heavy oil as an auxiliary fuel to generate electricity in a dual fuel engine. In order to improve engine efficiency with the carbonized gas having a low calorific value, it is desirable to employ a turbocharger or an intercooler.

[0027] Carbon dioxide 30 contained in the exhaust gas from the pyrolysis furnace 33 is separated and recovered by a chemical absorption method. After the exhaust gas from pyrolysis is subjected to pretreatment such as dust removal, desulfurization, and denitration, it passes through an absorption tower into which an amine-based aqueous solution that easily absorbs carbon dioxide 30 is dropped, and is absorbed in the liquid. The aqueous solution is then heated to vaporize the carbon dioxide 30, and high-purity carbon dioxide 30 is obtained in the separation tower and stored in a storage tank 47 described below. At this time, the heat source for the separation tower uses the exhaust heat from the pyrolysis furnace 33. Carbon dioxide recovery from the exhaust gas can also be achieved by a separation method using a special filter. The process of separating and recovering carbon dioxide 30 from the exhaust gas from the pyrolysis furnace 33 is an example of the gas extraction section of the present invention.

[0028] As shown in Figure 3, the humus liquid production section 4 is composed of a first production section 41 that produces humus liquid 12, a second production section 42 that produces gas-containing humus liquid 13 from the humus liquid 12, and a third production section 43 that produces iron-containing humus liquid 14 from the gas-containing humus liquid 13.

[0029] In the first generation section 41, as shown in FIG. 2, the humus liquid 12 is generated from the organic matter 40 and the residue of the biochar 31 extracted from the biochar production section 3. The organic matter 40 here is not limited to the residue generated in the raw material production section 2, but may be seaweed and algae, algae residues generated by collection and cultivation in the fishing industry and their processing, wood, bamboo, herbaceous plants, vegetable waste, or fallen leaves and branches, but is not limited thereto. The first generation section 41 is composed of a generation tank 44 for generating the humus liquid 12 and an organic matter tank 45 for storing the organic matter 40. In the first generation section 41, the organic matter 40 in the organic matter tank 45 is immersed in the wood vinegar 11 filled in the generation tank 44 to generate the humus liquid 12. It is desirable that the wood vinegar 11 used has a moisture content of 80% or more, an organic acid content of 1.0% or more, a pH (H2O) of 5.0 or less, and an electrical conductivity of 1.0 mS / cm or more.

[0030] In the first generation section 41, the organic matter 40 is mixed in a production tank at a volume ratio of 1.0 to 0.5 or more of wood vinegar 11, stirred with a stirrer or the like, and soaked for at least 3 hours, and for up to 600 hours depending on the type of organic matter 40. By soaking for a long period of time, wood, grass, residues, etc. that have not yet been humified can be impregnated with wood vinegar 11. The solution in the production tank after the curing period has passed becomes humus liquid 12. Humus liquid 12 is mainly composed of humin, humic acid, and fulvic acid, and can be used for soil improvement, chelating marine, fruit cultivation, fish and livestock farming, etc.

[0031] Humin, fulvic acid, and humic acid contained in the humus liquid 12 are classified according to their solubility in alkali and acid, according to the classification of the International Humic Substances Society, to which the Japanese Humic Substances Society belongs. Humic acid is an organic substance (non-living organic matter) whose chemical structure is not specified and which is produced when living organic matter is decomposed by microbial and chemical action. Fulvic acid is a component that is soluble in alkali and soluble in acid, and humic acid is also a component that is soluble in alkali but insoluble in acid. Humin is a component that is insoluble in alkali and in acid. The level of fulvic acid contained in a fulvic acid liquid, etc. is not appropriate to be specified by the concentration of each specific component because fulvic acid is a mixed substance and is greatly affected by the presence or absence of other organic matter, and in some cases it cannot be specified by a specific numerical value.

[0032] Humin, fulvic acid, and humic acid contain many carboxyl groups (-COOH) and phenolic hydroxyl groups (R-OH), and the bonding strength between the oxygen (O) and hydrogen (H) at the ends of these bonds is extremely weak, so when the hydrogen at the end is separated from the bond, the oxygen left behind develops a negative charge. Since iron ions such as ferrous iron are cationic, they bond with negatively charged humus. A substance in which fulvic acid and iron ions are bonded in this way is called ferric fulvic acid.

[0033] In the second generation section 42, the carbon dioxide 30 recovered from the iron making section 6 and the biochar production section 3 is dissolved in the humus liquid 12. The second generation section 42 is composed of a gas dissolving section 46 that dissolves gas in the humus liquid 12, and a storage tank 47 that stores the carbon dioxide 30 recovered in the biochar production section 3 and the iron making section 6. The gas dissolving section 46 is a sealed container, and the gas in the storage tank 47 is filled inside, and the gas-containing humus liquid 13 is generated by dropping or spraying the humus liquid 12 from above. In this embodiment, the carbon dioxide recovered in the pyrolysis furnace 33 and the iron making section 6 of the biochar production section 3 is used, but this is not limited to this, and other gases may be used.

[0034] In the gas dissolving section 46, the carbon dioxide 30 is supplied in a sealed device, so that the efficiency is higher than that of the conventional supply method by aeration. When the carbon dioxide 30 is supplied by aeration, it escapes before dissolving in the liquid, but in the present invention, since the gas dissolving section 46 is sealed, only the supplied amount dissolves in the liquid and there is no waste. This makes it possible to realize a high dissolved carbon dioxide concentration in the gas-containing humus liquid 13. In this embodiment, the Oxygen Fighter (registered trademark) of Iwatani Corporation is used as the gas dissolving section 46, but this is not limited to this and other bubble-free dissolving devices may be used. According to the gas dissolving section 46, the gas dissolved in the humus liquid 12 can be replaced with the carbon dioxide 30 to obtain the gas-containing humus liquid 13, so that a higher carbon dioxide concentration can be realized compared to aeration. The amount of carbon dioxide 30 supplied from the storage tank 47 to the gas dissolving section 46 does not necessarily have to be constant, and the supply amount may be changed depending on the equipment and the external environment.

[0035] The third generation section 43 generates the iron-containing humus liquid 14 by immersing the steel slag 61 generated in the steelmaking section 6 in the gas-containing humus liquid 13. As shown in Fig. 4, a mesh-shaped support section 49 on which the steel slag 61 is placed is immersed for a predetermined time in a tank 48 filled with the gas-containing humus liquid 13. At this time, the weight ratio of the gas-containing humus liquid 13 to the steel slag 61 is preferably in the range of 50:1 to 50:50, but is not limited to this range.

[0036] The steel slag 61 on the support part 49 is replaced depending on the concentration of divalent iron fulvic acid in the iron-containing humus liquid 14. The replaced steel slag 61 and the steel slag 61 precipitated in the lower part of the tank 48 can be used as chelated precipitated iron 61A containing a large amount of divalent iron ions. Specifically, by supplying the chelated precipitated iron 61A to the sea or rivers, or to farmland, divalent iron ions are supplied to living organisms, thereby improving the environment.

[0037] The steel slag 61 is a by-product generated in the steelmaking process, and contains a large amount of iron that is dissolved and ionized by organic acids, and has a high solubility of iron ions, so it is considered to be suitable as a material for eluting divalent iron ions. Divalent iron is easily eluted during the oxidation process in water and is absorbed by living organisms in the form of divalent iron ions, but divalent iron is a very unstable substance. The fulvic acid contained in the gas-containing humic liquid 13 has a carboxyl group or a carbonyl group, and divalent iron ions generated under anoxic conditions bind to the fulvic acid as a complex to become fulvic acid iron. The divalent iron ions become stable fulvic acid iron by chelating with the fulvic acid, and can exist stably even under aerobic conditions. Since the steel slag 61 is alkaline, humic acid, which is present in greater amounts than fulvic acid in the gas-containing humic liquid 13 but does not dissolve in water unless the atmosphere is alkaline, can also be used as a chelating agent for divalent iron. As a result, the iron-containing humus liquid 14 contains a large amount of iron fulvic acid and iron humate, and since it has stable divalent iron ions, it can be used for various purposes.

[0038] FIG. 5 shows the measurement results of the total organic carbon (TOC) content in the iron-containing humus liquid 14. A predetermined steel slag 61 is added to the humus liquid 12 adjusted to 700 mg / mL with artificial seawater, and the liquid is filtered after three hours. Iron bound to organic matter is separated and collected by solid-phase extraction, eluted with acid, and the iron is measured by a coloring method. As shown in FIG. 5, the solid line is the adjusted iron-containing humus liquid 14, the dotted line is the humus liquid 12, and the dashed line is the eluate of the steel slag 61. The iron-containing humus liquid 14 shows a higher carbon content than the other solutions. FIGS. 6 and 7 show the organic carbon content when steel slag 61 with different pH values ​​is used. FIG. 6 shows the relationship between the pH of the steel slag 29 of the four prepared samples and the soaking time in the humus liquid 12. FIG. 7 shows the results of the iron-containing humus liquid in which steel slag 61 with different pH values ​​was soaked in the humus liquid 12 for 6 hours or 24 hours. As a result of the test, the solution in which the weakly alkaline iron and steel slag 61 was soaked in the humus liquid 12 for 24 hours had the highest iron ion content of 1000 ppm. In contrast, even if the strongly alkaline iron and steel slag 61 was soaked in the humus liquid 12 for more than 24 hours, the iron ion content was only about 200 ppm. For this reason, it is preferable to soak the weakly alkaline iron and steel slag 61 in the gas-containing humus liquid 13 in the third generation section 43 for more than 3 hours, and more preferably for more than 6 hours.

[0039] 8 to 10 show the relationship between the period during which steel slag 61 was soaked in humus liquid 12 and the pH value and the concentration of divalent iron ions. FIG. 8 shows the results of soaking humus liquid 12 and steel slag 61 in a 1:1 weight ratio. After 7 days of soaking, the concentration of divalent iron ions reaches a maximum, and the pH value is 7.05, which is approximately neutral. After 3 days, the pH value is acidic to weakly acidic, and the concentration of divalent iron ions is 1000 to 2000 ppm.

[0040] The results of soaking the humus solution 12 and steel slag 61 in a weight ratio of 2:1 are shown in Fig. 9. After 7 days of soaking, the concentration of divalent iron ions was at its maximum, and the pH value was 5.3, which is slightly acidic. After 3 days, the pH value was acidic to slightly acidic, and the concentration of divalent iron ions was 1000 to 2000 ppm.

[0041] FIG. 10 shows the results of soaking the soil with humus liquid 12 and steel slag 61 in a weight ratio of 10:1. After 7 days of soaking, the concentration of divalent iron ions reaches a maximum, and the pH value is 4.11, indicating a weak acidity. After 3 days, the pH value is acidic to weakly acidic, and the concentration of divalent iron ions is 1000 to 3000 ppm. From the above, even with a mixing ratio of humus liquid 12 and steel slag 61 of 10:1, a sufficient concentration of divalent iron ions can be obtained after 7 days, compared to when there is a large amount of steel slag 61.

[0042] As shown in FIG. 2, the coke production unit 5 produces bio-coke 51 by mixing biochar 31 produced by the biochar production unit 3 with a biomass raw material, heating and compressing the mixture. In the coke production unit 5, the biochar 31 and other biomass raw materials are filled in a cylinder, pressurized at 10 to 20 MPa, heated at 150°C to 300°C for a predetermined time, and then cooled to produce bio-coke 51. In this embodiment, as shown in FIG. 1, a production device 52 that continuously performs pressurization, heating, and cooling is used. By heating at a predetermined temperature, lignin, cellulose, and hemicellulose contained in the biomass raw material mixed with the biochar 31 are pyrolyzed, especially hemicellulose, and the heated steam generated in the cylinder causes a hydrolysis reaction of cellulose and lignin at a low temperature. The bio-coke 51 has excellent strength and shape stability during combustion, and can increase energy density and reduce transportation costs. The raw material production unit 2, the biochar production unit 3, and the coke production unit 5 are examples of the raw material production unit of the present invention. The wood material 20, the biochar 31, and the biocoke 51 are examples of raw materials of the present invention.

[0043] As shown in FIG. 2, the steelmaking section 6 adds a part of the bio-coke 51 produced in the cokemaking section 5 to the coal coke to make steel, and supplies the by-products, carbon dioxide 30 and steel slag 61, to the humus liquid generating section 4. In the steelmaking section 6, iron ore, sintered ore, and limestone are subjected to molten iron pretreatment, and the iron ore is reduced and carburized in the blast furnace 62 to obtain molten pig iron. The obtained pig iron is decarburized to a required carbon amount in a converter to remove impurities. The reaction at this time is the oxidation of carbon in the pig iron by pure oxygen gas and iron oxide, and the remaining oxygen that contributed to this decarburization reaction remains in the pig iron. The steel from which the impurities have been removed is formed into a plate-shaped product by rolling, and becomes a roll. In this embodiment, a predetermined amount of bio-coke 51 is added to the coal coke in the blast furnace 62 and converter in the steelmaking section 6 within a range that does not affect the product quality. It is desirable to keep the amount of bio-coke 51 added within 50%.

[0044] The steel slag 61 is a by-product of steelmaking produced by dissolving certain components during reduction and refining of metals from ores, and includes converter slag, pre-treatment slag, decarburization slag, dephosphorization slag, desulfurization slag, desiliconization slag, electric furnace oxidation slag, electric furnace reduction slag, secondary refining slag, casting slag, and mixer slag. As shown in Figs. 2 to 4, the steel slag 61 is used in the third generation section 43 to dissolve divalent iron ions into the gas-containing humus liquid 13 to produce the iron-containing humus liquid 14. In the steelmaking section 6, the bio-coke 51 may be processed into a predetermined shape, and the carbonized powder may be blown into the blast furnace 62 together with pulverized coal, or the bio-coke 51 may be mixed with coal powder and charged into the blast furnace 62 or converter. In addition, briquettes may be produced by adding 20% ​​of the bio-coke 51 and lime, and used as a desulfurization agent or a denitrification agent.

[0045] Carbon dioxide 30 contained in exhaust gas from a blast furnace 62 or a converter furnace is separated and recovered by a chemical absorption method. After pretreatment such as dedusting, desulfurization, and denitration, the exhaust gas from the blast furnace 62 passes through an absorption tower into which an amine-based aqueous solution that easily absorbs carbon dioxide 30 is dripped, and the carbon dioxide 30 is absorbed in the liquid. The aqueous solution is then heated to vaporize the carbon dioxide 30, and high-purity carbon dioxide 30 is obtained in the separation tower and stored in a storage tank 47. The process of separating and recovering carbon dioxide 30 from the exhaust gas from the blast furnace 62 or a converter furnace is an example of the gas extraction section of the present invention.

[0046] The pH adjustment unit 8 adjusts the pH value of the iron-containing humus liquid 14 generated by the third generation unit 43. The pH adjustment unit 8 inputs water (seawater) or a pH adjuster by a control valve (not shown) to adjust the pH value of the iron-containing humus liquid 14 to a predetermined range. The pH value of the iron-containing humus liquid 14 can be adjusted to an optimal value according to the environment of the rearing unit 7. The input amount of water or pH adjuster is optimally set according to the pH value of the iron-containing humus liquid 14 or the pH value of the rearing unit 7. Specifically, the environmental load is reduced by setting the value close to the pH value of the rearing unit 7. The input amount in the pH adjustment unit 8 may be controlled according to the detection result of a pH sensor provided in the rearing unit 7.

[0047] Next, the flow of the biomass energy conversion system 1 will be described with reference to Figures 1 and 11. The raw material wood 10 is cut into a predetermined shape in the raw material production section 2 to obtain wood material 20 (S1). Residues generated during processing of the wood 10 in the raw material production section 2 are added to the organic matter 40 stored in the organic matter tank 45. The wood material 20 is pyrolyzed in the pyrolysis furnace 33 of the biochar production section 3 to produce biochar 31, and wood vinegar 11 is obtained as a by-product from the extraction section 34 (S2). Carbon dioxide 30 contained in the exhaust gas from the pyrolysis furnace 33 is separated and collected, and stored in the storage tank 47.

[0048] In the coke production section 5, the biochar 31 produced in the biochar production section 3 and other biomass raw materials are heated and compressed under predetermined conditions to produce biocoke 51 (S3). The obtained biocoke 51 is added to coal coke in a blast furnace 62 or converter in the steelmaking section 6 for use (S4). In the steelmaking section 6, carbon dioxide 30 is separated and recovered from the exhaust gas, and steel slag 61 generated as a by-product of steelmaking is obtained.

[0049] In the first production section 41, the wood vinegar 11 is subjected to a predetermined pretreatment, and the organic matter 40 is soaked in the humus liquid 12 under predetermined conditions (S5). In the second production section 42, the carbon dioxide 30 recovered from the exhaust gas of the biochar production section 3 and the iron making section 6 is dissolved in the humus liquid 12 in the gas dissolving section 46, and the gas-containing humus liquid 13 is obtained (S6). In the third production section 43, the iron and steel slag 61 is soaked in the gas-containing humus liquid 13 under predetermined conditions, and the iron-containing humus liquid 14 is obtained (S7).

[0050] The iron-containing humus liquid 14 is adjusted to an optimized pH value for the rearing section 7 by the pH adjusting section 8 (S8) and sprayed onto the rearing section 7 (S9). The iron-containing humus liquid 14 containing divalent iron ions is supplied as nutrients to the marine aquaculture site 71 and also sprayed onto the farmland 72. The iron-containing humus liquid 14 may be supplied to the rearing section 7 by an automatic transport system such as a pipeline. The algae cultivated in the marine aquaculture site 71 are seaweeds or symbiotic algae such as green algae such as Green Laver and Ulva, which are multicellular organisms, red algae such as Porphyra japonica, Porphyra serrata, Funori, and Agar, and brown algae such as Laminaria tularensis, Hijiki, Mozuku, and Wakame. Shellfish include oysters, scallops, abalone, corbiculatus, and clams, and echinoderms include sea urchins and sea cucumbers. When cultivating fish in the marine aquaculture site 71, it is desirable to divide the fish cages in the sea with nets or the like and add iron-containing humus liquid 14. The iron-containing humus liquid 14 is rich in divalent iron ions and fulvic acid iron, and has a high concentration of dissolved carbon dioxide, so that the productivity of photosynthetic organisms in the marine aquaculture site 71 and its surroundings is increased, and the water quality is purified by the organisms. Furthermore, the outflow of divalent iron ions from the iron-containing humus liquid 14 suppresses the generation of toxic gases such as hydrogen sulfide, and sludge is improved by the proliferation of anaerobic attached diatoms in the bottom sediment. This chain reaction creates a marine forest rich in biological resources. Furthermore, by spraying the iron-containing humus liquid 14 rich in divalent iron ions on the farmland 72, plants can take in minerals (trace elements) in the soil through chelation, and carbon dioxide necessary for photosynthesis is also supplied, resulting in effects such as soil improvement and recovery from salt damage.

[0051] According to this configuration, the iron-containing humus liquid 14 can be generated by the humus liquid generation unit 4, and the iron-containing humus liquid 14 can be used in the marine aquaculture site 71 or in the agricultural land 72, whereby the divalent fulvic acid iron contained in the iron-containing humus liquid 14 is absorbed by living organisms, thereby reducing diseases in agricultural crops and realizing fertile fields and a sea area rich in marine life. In addition, the specific gas containing carbon dioxide 30 generated by the biochar production unit 3 and the iron making unit 6 is extracted and dissolved in the humus liquid 12 in the second generation unit 42, so that the amount of carbon dioxide 30 emitted by the biomass energy conversion system 1 as a whole can be reduced. In addition, the iron-containing humus liquid 14 produced by the process of this embodiment can exist as divalent iron ions without becoming trivalent iron ions and immediately settling as solid iron, so that divalent iron ions can be efficiently supplied to living organisms.

[0052] The bio-coke 51 is produced from wood 10 in the biochar production section 3 and the coke production section 5, the bio-coke 51 is used for steel making in the steel making section 6, the gas-containing humus liquid 13 is produced by dissolving specific gases including carbon dioxide 30 from the by-product wood vinegar 11 in the second production section 42, and the iron-containing humus liquid 14 is produced by soaking the steel slag 61 in the third production section 43, so that the process can be completed within the biomass energy conversion system 1 without discharging by-products, residues, etc. This makes it possible to simultaneously improve the energy conversion efficiency of the biomass energy conversion system 1 as a whole and reduce the environmental load.

[0053] According to this configuration, bio-coke 51 can be obtained by compressing bio-charcoal 31 at a predetermined temperature in the coke production section 5, and the bio-coke 51 can be used in the steelmaking section 6 to reduce carbon dioxide emissions by replacing fossil fuels. In addition, specific gases including carbon dioxide 30 generated by the steelmaking section 6 are extracted and dissolved in the humus liquid 12 in the second production section 42, so that the amount of carbon dioxide 30 emitted from the entire biomass energy conversion system can be reduced.

[0054] According to this configuration, the third generation section 43 generates the iron-containing humus liquid 14 by disposing the steel slag 61 in the tank 48 and immersing it in the gas-containing humus liquid 13, so that the iron-containing humus liquid 14 can be generated by a simple method. In addition, the iron ions contained in the steel slag 61 generated as a by-product or residue in the steelmaking section 6 are converted into divalent iron fulvic acid by the chelating agent contained in the humus liquid 12. The divalent iron fulvic acid generated by this process is stable in state, and is unlikely to change to trivalent iron fulvic acid due to oxidation, unlike conventional divalent iron fulvic acid. This makes it possible to stably deliver divalent iron fulvic acid to living organisms. Furthermore, the steel slag 61 used in the third generation section 43 has iron ions dissolved therein, so there is no risk of oxidation, and it can be widely used as riverside gravel, cement, ground improvement material, and civil engineering materials.

[0055] According to this configuration, the pH adjustment unit 8 adjusts the pH value of the iron-containing humus liquid 14 in accordance with the rearing unit 7, so that the iron-containing humus liquid 14 can be supplied while minimizing the environmental load on the rearing unit 7. Since the pH adjustment unit 8 adjusts the pH value of the iron-containing humus liquid 14, the pH value is adjusted at the final stage of supplying the iron-containing humus liquid 14 from the biomass energy conversion system 1 to the rearing unit 7. If the pH value of the humus liquid 12 were adjusted here, the pH value would change when it passes through the iron unit 27. In contrast, the biomass energy conversion system 1 of this embodiment adjusts the pH value of the iron-containing humus liquid 50, so that the load on the rearing unit 7 can be reduced.

[0056] The biomass energy conversion system and biomass energy conversion method according to the present invention are not limited to the above-described embodiment, and various modifications are possible within the scope of the gist of the invention described in the claims.

[0057] In the above embodiment, biochar 31 is used to produce bio-coke 51, but the present invention is not limited to this. Bio-coke may be produced by directly compressing and heating herbaceous plants, wood, rice husks and rice straw, nuts, food waste, agricultural waste, etc. This allows the production of bio-coke with high energy density.

[0058] In the above embodiment, the bio-coke 51 is produced by compressing and heating the bio-char 31 in the coke production unit 5, but the present invention is not limited to this. The bio-char 31 may be directly used in the steelmaking unit 6. In this case, it is preferable to process the bio-char 31 into a predetermined shape and inject the carbonized powder into the blast furnace 62 together with pulverized coal.

[0059] In the above embodiment, carbon dioxide 30 is separated and collected from the exhaust gas of the steelmaking section 6 and dissolved in the humus liquid 12, but the gas to be dissolved is not limited to carbon dioxide 30. For example, nitrogen, hydrogen, oxygen, etc. may be used. For extraction of gases such as nitrogen and oxygen, a PSA method that is selective adsorption by an adsorbent, a membrane method that uses filtration, a cryogenic method that extracts gases by differences in liquefaction temperature, etc. can be used.

[0060] In the above embodiment, the humus liquid 12 is generated by immersing the organic matter 40 in the organic matter tank 45 in the wood vinegar 11 filled in the generation tank 44, but the present invention is not limited to this. For example, a vibration device can be placed at the bottom of the generation tank 34 to increase the reaction rate between the wood vinegar 11 and the organic matter 40. This can increase the production efficiency of the humus liquid 12.

[0061] In the above embodiment, the iron-containing humus liquid 14 is generated by placing the steel slag 61 in the tank 48 in the third generation section 43 and immersing it in the gas-containing humus liquid 13, but this is not limited thereto. For example, a vibration device can be placed at the bottom of the tank 48 to increase the reaction rate between the steel slag 61 and the gas-containing humus liquid 13. This can increase the production efficiency of the iron-containing humus liquid 14. [Explanation of symbols]

[0062] 1. Biomass energy conversion system 2 Raw material manufacturing department 3. Biochar Production Department 4 Humus liquid generation section 5. Coke Manufacturing Department 6. Steelworks Department 7. Breeding Department 8 pH adjustment section 11 Wood vinegar 12 Humic liquid 13 Gas-containing humus liquid 14 Iron-containing humus liquid 20 Wood materials 30 Carbon Dioxide 31 Biochar 41 1st generation part 42 Second generation part 43 Third generation part 51 Bio-coke 61 Steel slag

Claims

1. a raw material production section that carbonizes the biomass raw material to produce raw material and removes impurities from the dry distillation gas to extract wood vinegar; a steelmaking section that uses the raw materials produced in the raw material production section in a blast furnace or a converter to obtain an iron-containing material; A gas extraction unit that extracts a specific gas including carbon dioxide from exhaust gas discharged from at least one of the raw material production unit or the steelmaking unit; A biomass energy conversion system comprising a humus liquid generation unit having: a first generation unit that generates a humus liquid containing fulvic acid by soaking organic matter in the wood vinegar; a second generation unit that dissolves the specific gas extracted from the gas extraction unit in the humus liquid to generate a gas-containing humus liquid; and a third generation unit that soaks the iron-containing material in the gas-containing humus liquid to generate an iron-containing humus liquid.

2. The raw material production unit further includes a coke production unit for compressing the biomass raw material to produce bio-coke, The biomass energy conversion system according to claim 1, characterized in that the steelmaking section uses the bio-coke as a raw material.

3. The third generation unit has a tank that contains the gas-containing humus liquid and a mesh-shaped holding unit arranged in the tank, The biomass energy conversion system according to claim 1, characterized in that the iron-containing material is placed in the holding portion and immersed in the gas-containing humus liquid in the tank, thereby generating iron-containing humus liquid.

4. Further comprising a pH adjustment unit for adjusting the pH value of the iron-containing humus liquid generated by the third generation unit; The biomass energy conversion system according to any one of claims 1 to 3, characterized in that the pH adjustment unit adjusts the pH value of the iron-containing humus liquid based on the environment of the breeding unit to which the iron-containing humus liquid is supplied.

5. A step of producing a raw material by carbonizing the biomass raw material in a pyrolysis furnace and obtaining a dry distillation gas; A step of removing impurities from the dry distillation gas to extract wood vinegar; using the raw material in a blast furnace for iron making to obtain iron-containing material; A step of extracting a specific gas including carbon dioxide from exhaust gas discharged from at least one of the blast furnace or the pyrolysis furnace; A step of producing a humus solution containing fulvic acid by soaking organic matter in the wood vinegar; A step of dissolving the specific gas in the humus liquid to produce a gas-containing humus liquid; and a step of immersing the iron-containing material in the gas-containing humus liquid to produce an iron-containing humus liquid.

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