Manufacturing method of the article

Abstract

To provide a method for manufacturing an article in which exhaust gas of a stable gas composition is recovered and a new article of uniform-quality can be efficiently manufactured.SOLUTION: Provided is a method for manufacturing an article. The method has: a first process of supplying at least organic components out of discarded articles and / or gasified substance thereof into a melting furnace together with ore and refining them; a second process of recovering exhaust gas which was discharged from the melting furnace and contains carbon monoxide and carbon dioxide; a third process of obtaining monomers constituting the organic components by using carbon monoxide in the exhaust gas; a fourth process of obtaining organic components by polymerizing monomers alone or with other monomers; and a fifth process of manufacturing an article by using the organic components.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing an article. [Background technology]

[0002] A method for producing recycled tires from waste tires is known (see Patent Document 1). In this tire production method, first, the waste tires are thermally decomposed at high temperatures to generate a gas containing C1 gas. Next, the carbon monoxide contained in this gas is converted into isoprene by microorganisms to obtain recycled tire material. The recycled tire material is then polymerized to produce polyisoprene rubber, which is then processed as the main material to produce recycled tires.

[0003] However, because this method simply involves heating waste tires to a high temperature to cause thermal decomposition, the inventors have found through their studies that the composition of the gas generated varies greatly depending on the type of waste tires, heating conditions, etc. Furthermore, the use of gases with variable gas compositions is likely to result in variations in the production volume, quality, etc. of recycled tire material and polyisoprene. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Re-table No. 2014 / 115437 Summary of the Invention [Problem to be solved by the invention]

[0005] In view of the above circumstances, the present invention aims to provide a method for manufacturing an article that can recover exhaust gas with a stable gas composition and efficiently manufacture new articles of uniform quality. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided a method for manufacturing an article, which includes a first step of supplying at least organic components of discarded articles and / or their gasified products to a smelting furnace together with ore for refining, a second step of recovering exhaust gas discharged from the smelting furnace and containing carbon monoxide and carbon dioxide, a third step of obtaining monomers constituting the organic components using the carbon monoxide in the exhaust gas, a fourth step of polymerizing the monomers alone or with other monomers to obtain the organic components, and a fifth step of manufacturing an article using the organic components.

[0007] According to one aspect of the present invention, exhaust gas with a stable gas composition can be recovered and new products with uniform quality can be efficiently manufactured. Furthermore, by effectively utilizing exhaust gas, the amount of exhaust gas emitted can be reduced, thereby realizing a circular economy (a material recycling-based society). [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram showing the overall configuration of a tire manufacturing system. DETAILED DESCRIPTION OF THE INVENTION

[0009] The method for manufacturing an article of the present invention will be described in detail below based on preferred embodiments. In the following description, a tire will be used as an example of a representative article. First, before describing the tire manufacturing method of this embodiment, a tire manufacturing system will be described. FIG. 1 is a schematic diagram showing the overall configuration of a tire manufacturing system. The manufacturing system 1 shown in FIG. 1 includes a blast furnace (melting furnace) 2, a CO concentrating section 3, a monomer producing section 4, a rubber component synthesizing section 5, and a tire manufacturing section 6.

[0010] In this embodiment, the exhaust gas discharged from the blast furnace 2 is utilized, but other furnaces attached to a steel mill or a smelter may also be used. Preferred examples of such furnaces include shaft furnaces, converters, and electric furnaces. In each furnace, exhaust gas is generated (produced) during melting and refining of the contents. The exhaust gas typically contains carbon dioxide and carbon monoxide as well as other gas components such as nitrogen, oxygen, water vapor, and methane. The exhaust gas (blast furnace gas) from blast furnace 2 is a gas generated when pig iron is produced in blast furnace 2, and contains 10 to 15 volume % carbon dioxide, 55 to 60 volume % nitrogen, 25 to 30 volume % carbon monoxide, and 1 to 5 volume % hydrogen.

[0011] In addition, exhaust gas from a converter (converter gas) is a gas generated when steel is produced in a converter, and contains 15 to 20 volume % carbon dioxide, 50 to 60 volume % carbon monoxide, 15 to 25 volume % nitrogen, and 1 to 5 volume % hydrogen. By using these exhaust gases, carbon dioxide that has conventionally been emitted into the atmosphere can be effectively utilized, reducing the burden on the environment and increasing the degree of material circulation.

[0012] The CO concentration section 3 increases the concentration of carbon monoxide in the exhaust gas. Examples of methods for increasing the concentration of carbon monoxide in exhaust gas include I) a method in which carbon dioxide is temporarily separated from exhaust gas, the separated carbon dioxide is converted into carbon monoxide, and the converted carbon dioxide is then recombined with the exhaust gas, and II) a method in which carbon monoxide is converted into carbon dioxide by burning exhaust gas, and then the carbon dioxide is converted back into carbon monoxide. In the CO concentrating section 3, the concentration of carbon monoxide in the exhaust gas may be increased by adding separately prepared carbon monoxide to the exhaust gas.

[0013] In method I, when separating carbon dioxide from exhaust gas, for example, a low-temperature separation type (cryogenic type) separator, a pressure swing adsorption (PSA) type separator, a membrane separation type separator, a temperature swing adsorption (TSA) type separator, an amine absorption type separator, an amine adsorption type separator, etc. can be used, and one of these can be used alone or two or more can be used in combination. On the other hand, in the method II, when carbon monoxide is converted to carbon dioxide by burning exhaust gas, for example, a combustion furnace (combustion boiler) or the like can be used.

[0014] In methods I and II, the conversion of carbon dioxide to carbon monoxide can be carried out, for example, by a reverse water gas shift reaction carried out in one reactor, a chemical looping method in which multiple reactors are switched between, or an electrolysis method of carbon dioxide, and any of these methods can be used alone or in combination of two or more. The chemical looping method is a method in which the reverse water gas shift reaction is divided into two reactions: a conversion reaction of carbon dioxide to carbon monoxide and a reduction reaction with hydrogen (a reducing substance), and these reactions are mediated by a reducing agent. Then, multiple reactors are switched between, and the conversion reaction and the reduction reaction are carried out alternately in one reactor. In this case, the reducing agent may be in the form of a fixed bed fixed in each reactor, or in the form of a fluidized bed (moving bed) circulating between the reactors.

[0015] The reducing agent used in the reverse water gas shift reaction is preferably in the form of, for example, particles (granules), flakes, pellets, etc. A reducing agent in such a shape can increase the packing efficiency into the reactor (the tubes of a multi-tubular reactor) and can further increase the contact area with the exhaust gas (carbon dioxide) supplied to the reactor. When the reducing agent is particulate, its volume-average particle size is not particularly limited, but is preferably 1 to 50 mm, more preferably 3 to 30 mm. In this case, the contact area between the reducing agent and the exhaust gas can be further increased, and the efficiency of converting carbon dioxide to carbon monoxide can be further improved. Similarly, in the case of the chemical looping method, regeneration (reduction) of the reducing agent by hydrogen can also be carried out more efficiently. The particulate reducing agent is preferably a granulated product produced by tumbling granulation, since this results in a higher degree of sphericity.

[0016] The reducing agent may be supported on a carrier. The constituent material of the carrier is preferably a material that is difficult to denature regardless of contact with exhaust gas, reaction conditions, etc., and is not particularly limited. Examples include carbon materials (graphite, graphene, etc.), zeolite, montmorillonite, silica, zirconia, titania, magnesia, alumina, vanadium oxide, and composite oxides thereof. A carrier made of such a material is preferable because it does not adversely affect the reaction of the reducing agent and has excellent reducing agent supportability. Here, the carrier does not participate in the reaction of the reducing agent, but simply supports (holds) the reducing agent. One example of such a form is a configuration in which at least a portion of the surface of the carrier is coated with the reducing agent.

[0017] The metal oxide (oxygen carrier) contained in the reducing agent is not particularly limited as long as it can reduce carbon dioxide. Specifically, the metal oxide preferably contains at least one metal element selected from Groups 3 to 12, more preferably at least one metal element selected from Groups 4 to 12, and even more preferably at least one element selected from titanium, vanadium, iron, copper, zinc, nickel, manganese, chromium, and cerium, with iron-containing metal oxides or composite oxides being particularly preferred. These metal oxides are useful because they have particularly good efficiency in converting carbon dioxide to carbon monoxide.

[0018] In the monomer production section 4, carbon monoxide in the exhaust gas is used to produce monomers that constitute the rubber component (organic component). Here, the monomer preferably includes at least one selected from the group consisting of ethylene, propylene, isoprene, butadiene, isobutene, butanediol compounds, butanol compounds, butenal compounds, and succinic acid. Butanediol compounds include 1,4-butanediol, 2,3-butanediol, and 1,3-butanediol. Butanol compounds include 1-butanol, 2-butanol, and isobutanol. Butenal compounds include 2-butenal and 3-butenal. Among these, it is preferable that the monomer contains at least one selected from the group consisting of isoprene and butadiene, as this is suitable for synthesizing the rubber component of a tire.

[0019] In the monomer production section 4, A: a monomer may be obtained directly from carbon monoxide by the action of a catalyst or a microorganism, or B: an intermediate product may be produced from carbon monoxide by the action of a microorganism, and then a monomer may be obtained from the intermediate product by the action of a catalyst. Examples of catalysts that can be used in method A include ruthenium, rhodium, manganese, germanium, tantalum, zirconium, niobium, hafnium, lanthanum, cerium, aluminum, magnesium, copper, zinc, silicon, and oxides thereof, and any of these can be used alone or in combination of two or more. Examples of intermediate products produced by method B include ethanol, isopropanol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, acetaldehyde, acetic acid, lactic acid, and succinic acid. Examples of catalysts that can be used in method B include germanium, tantalum, zirconium, niobium, hafnium, lanthanum, cerium, aluminum, magnesium, tungsten, silver, copper, zinc, silicon, and oxides thereof, and any of these can be used alone or in combination of two or more.

[0020] Microorganisms that can be used in methods A and B include, for example, bacteria of the genus Clostridium, Moorella, Acetobacterium, Carboxydocella, Rhodopseudomonas, Eubacterium, Butyribacterium, Oligotropha, Bradyrhizobium, and Larsotonia. These microorganisms can be used as they are, or can be used after introducing nucleic acids encoding enzymes that synthesize the target substance (compound).

[0021] In the rubber component synthesis section 5, the above-mentioned monomers are polymerized alone or with other monomers to synthesize a rubber component. Specific examples of rubber components include isoprene homopolymers (isoprene rubber), butadiene homopolymers (butadiene rubber), copolymers of isoprene and butadiene (isoprene / butadiene copolymer rubber), copolymers of isoprene and styrene (isoprene / styrene copolymer rubber), copolymers of butadiene and styrene (butadiene / styrene copolymer rubber), copolymers of ethylene and propylene (ethylene / propylene copolymer rubber), etc. These rubber components are preferred because they are suitable as tire materials.

[0022] In the tire manufacturing section 6, tires (retreaded tires) are manufactured using the obtained rubber component. Specifically, the rubber component is subjected to a crosslinking reaction to manufacture the rubber portion of the tire. In addition to the rubber component (reclaimed rubber component), other rubber components may be used. Examples of other rubber components include newly synthesized rubber components. In this case, the greater the proportion of reclaimed rubber components used, the more the environmental impact can be reduced and the manufacturing costs of the resulting tire can be reduced.

[0023] In addition to the rubber component, compounds used in the manufacture of tires include pigments, sulfur, polyester compounds, and the like. The pigment is preferably a carbon pigment, more preferably a carbon pigment, and specific examples of the pigment include carbon black, acetylene black, and ketjen black. Reinforcing materials such as metal wires are also used in the manufacture of tires.

[0024] Manufactured tires (retreaded tires) are used, and when they reach the end of their useful life or deteriorate due to wear and tear, they are discarded and become waste tires. These waste tires (discarded items) are mixed with coke, including the rubber components (rubber part only), the waste tires themselves, and crushed waste tires, and then supplied to a blast furnace 2 together with iron ore, where iron is refined (steel is produced). The rubber component may be gasified by heating at a high temperature and then supplied to the blast furnace 2, or may be supplied together with the solid material to the blast furnace 2. For example, a coke oven, a gasification furnace, a combustion furnace, or the like can be used to generate the gasified material. In particular, it is preferable to supply the scrap tires themselves and / or their pulverized material to the blast furnace 2 without separating the rubber components from the scrap tires. In this case, the metal components (inorganic components) contained in the scrap tires can also be used in steelmaking, which contributes to further reduction of waste.

[0025] Next, a method for manufacturing a tire according to this embodiment (that is, a method for using the manufacturing system 1) will be described. The tire manufacturing method of this embodiment is a method for manufacturing a tire, which is carried out using, for example, a manufacturing system 1 shown in FIG. [1] First, at least the rubber component of the scrap tires and / or its gasified product is supplied to a blast furnace 2 together with iron ore and refined (first step). At this time, exhaust gas containing carbon monoxide and carbon dioxide is discharged from the blast furnace 2. [2] Next, the exhaust gas discharged from the blast furnace 2 is recovered (second step).

[0026] [3] Next, the recovered exhaust gas is supplied to the CO concentration section 3, and the concentration of carbon monoxide in the exhaust gas is increased by the method described above (an additional step between the second and third steps). Note that this step may be omitted. In this case, the exhaust gas from the blast furnace 2 can be used as is. [4] Next, the exhaust gas with an increased concentration of carbon monoxide is supplied to the monomer production section 4, where the monomer that constitutes the rubber component of the tire is produced in the manner described above (third step). [5] Next, the obtained monomer is supplied to the rubber component synthesis section 5, and a rubber component is synthesized in the manner described above (fourth step).

[0027] [6] Next, the rubber portion is obtained using the synthesized rubber component, additives, etc., and a tire (retread tire) is manufactured using reinforcing materials, etc. (fifth step). [7] The recycled and discarded tires are then supplied to the manufacturing system 1. They are then reborn as recycled tires through the above steps [1] to [6]. In this way, recycling and using scrap tires can significantly reduce the environmental impact. Furthermore, the exhaust gas from the blast furnace 2 has a stable gas composition, including carbon monoxide and carbon dioxide, making it easy to obtain rubber components with little variation in quality. Therefore, new tires of uniform quality can be efficiently manufactured.

[0028] Furthermore, the manufacturing method (manufacturing system 1) described above can effectively utilize exhaust gases, thereby reducing their emissions. Furthermore, by selecting an appropriate device configuration, it is possible to simultaneously achieve material recycling, chemical recycling, and thermal recycling of items. For these reasons, the manufacturing method (manufacturing system 1) described above can help realize a circular economy (a material recycling-based society). In particular, when waste tires themselves or crushed waste tires are used, the metal materials contained therein can also be effectively utilized.

[0029] Furthermore, it may be provided in the following aspects. The method for manufacturing an article, further comprising an additional step of increasing the concentration of carbon monoxide in the exhaust gas between the second step and the third step. In the method for manufacturing an article, the additional step includes separating the carbon dioxide from the exhaust gas, converting the separated carbon dioxide into carbon monoxide, and rejoining the exhaust gas. In the method for manufacturing an article, the additional step includes converting the carbon monoxide to carbon dioxide by burning the exhaust gas, and then converting the carbon dioxide to carbon monoxide. In the method for producing an article, in the third step, the monomer is obtained from the carbon monoxide by the action of a catalyst or a microorganism. In the method for producing an article, in the third step, an intermediate product is produced from the carbon monoxide by the action of a microorganism, and the monomer is obtained from the intermediate product by the action of a catalyst. In the method for manufacturing an article, in the first step, the article itself and / or its pulverized material is supplied to the melting furnace. The method for manufacturing an article, wherein the article further comprises an inorganic component. In the method for manufacturing an article, the article is a tire containing a rubber component as the organic component and a metal component as the inorganic component. Of course, this is not the case.

[0030] In the above embodiment, a tire containing a rubber component as an organic component and a metal component as an inorganic component has been described as an example of a typical article, but the article is not limited to this. The organic component of the article is not limited to a rubber component, but may be a resin component, an elastomer component, a combination thereof, etc. The inorganic component of the article is not limited to a metal component, but may be a ceramic component, a combination thereof, etc. The article may also be composed solely of organic components.

[0031] As described above, various embodiments of the present invention have been described, but these are presented as examples and do not limit the scope of the invention in any way. The novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. Such embodiments and their modifications are intended to be included within the scope and spirit of the invention, as well as within the scope of the inventions and their equivalents as set forth in the claims.

[0032] For example, the method for manufacturing an article of the present invention may have any other additional components, may be replaced with any components that perform the same function, or may omit some components. Furthermore, the method for producing an article of the present invention may include additional steps for any purpose. In addition, in the present invention, ore containing metals other than iron can be used instead of iron ore. In this case, the type of melting furnace used can be changed depending on the type of ore. [Explanation of symbols]

[0033] 1: Manufacturing system 2: Blast furnace 3 :CO concentration section 4: Monomer generation section 5: Rubber component synthesis section 6: Tire Manufacturing Department

Claims

1. 1. A method for manufacturing a retreaded tire, comprising: a first step of supplying scrap tires containing rubber components and metal components and / or pulverized scrap tires (containing the rubber components and the metal components) and coke together with ore to a melting furnace to obtain metals from the metal components and the ore; a second step of recovering exhaust gas discharged from the melting furnace and containing carbon monoxide and carbon dioxide; increasing the concentration of carbon monoxide in the exhaust gas; a third step of obtaining a monomer constituting the rubber component using the carbon monoxide in the exhaust gas; a fourth step of polymerizing the monomer alone or with other monomers to obtain the rubber component; a fifth step of manufacturing the retreaded tire using the rubber component, In the step of increasing the concentration of carbon monoxide, a method for manufacturing a retreaded tire includes: I: separating the carbon dioxide from the exhaust gas, converting the separated carbon dioxide into carbon monoxide, and rejoining the exhaust gas; II: combusting the exhaust gas to convert the carbon monoxide into carbon dioxide, and then converting the carbon dioxide into carbon monoxide; or III: adding separately prepared carbon monoxide to the exhaust gas.

2. The method for producing a retreaded tire according to claim 1, In the third step, the monomer is obtained from the carbon monoxide by the action of a catalyst or a microorganism.

3. The method for producing a retreaded tire according to claim 1 or 2, In the third step, an intermediate product is produced from the carbon monoxide by the action of microorganisms, and the monomer is obtained from the intermediate product by the action of a catalyst.

Images