JP2009112959A - Method and apparatus for impregnating solid material containing iron oxide with tar, method for utilizing solid material containing iron oxide-impregnated-with-tar to blast furnace, and method for utilizing gas containing tar - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for impregnating a solid material containing iron oxide with tar which can effectively hold organic waste including plastic waste in iron oxide raw materials such as iron ore and pellets for an iron-making process. <P>SOLUTION: The solid material containing iron oxide is impregnated with tar in a gas containing tar by putting the gas containing tar into contact with the solid material containing iron oxide in a countercurrent way in a moving bed reactor through charging the solid material containing iron oxide to the moving bed reactor from its upper part, filling it in the inside and discharging the solid material containing iron oxide from its bottom part, and also through introducing from the lower part, raising in its inside part, and discharging from its upper part, the gas containing tar generated by treating the organic waste with at least some of dry distillation, direct contact with a high temperature medium, partial combustion with a gas containing oxygen and steam reforming with steam and the gas containing oxygen; and the solid material containing the iron oxide impregnated with tar discharged from the bottom part is recovered. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention effectively uses organic waste such as waste plastics as a reducing agent and fuel for iron oxide raw materials in iron making processes such as iron ore and pellets, and also modifies iron ore containing hydrous iron oxide. The present invention relates to a pretreatment method and a pretreatment apparatus for an iron oxide-containing solid substance.

  Traditionally, organic waste treatment methods such as waste plastics have been centered on simple incineration and landfill, but the promotion of a recycling-oriented society has become a major social issue in recent years. There is a strong demand for effective use of resources as resources.

  Therefore, as a technology that can effectively use waste plastic as a resource, for example, as described in Patent Documents 1 and 2, after granulating or molding the waste plastic, the granulated plastic is blown from the tuyere of the blast furnace. Effectively used as a reducing agent and fuel for the blast furnace, or by charging molded plastic together with coal into the coke oven and dry distillation, and chemically recycling the waste plastic into coke, tar, coke oven gas (COG), etc. A method of effectively utilizing waste plastic by making good use of mass production capacity and high-temperature thermal energy possessed by the steelmaking process has been proposed and put into practical use.

  However, the problem with existing waste plastic processing methods that utilize the steelmaking process is that the number of blast furnaces and coke ovens in Japan is limited, and there are few new installations. There is a limit to the amount of waste plastic that can be charged and processed, and it is necessary to develop a new method to further promote the recycling of waste plastic using the steelmaking process. Can be mentioned.

  In addition, for organic waste other than waste plastic such as biomass, as well as waste plastic, there is a demand for effective utilization technology that utilizes mass production capacity and high-temperature thermal energy possessed by the steelmaking process.

  Therefore, as described in Patent Documents 3 and 4, organic waste such as plastic and biomass is used as a new method for recycling organic waste such as plastics by utilizing a steelmaking process. Was introduced into the furnace together with the iron-containing particles and pyrolyzed, and the carbon-containing material, which is the pyrolysis product of organic waste, was attached to iron oxides such as iron ore, and the carbon-containing material was attached. A method of using iron oxide as a raw material for iron making process has been proposed.

  In the example of Patent Document 3, organic waste containing plastic is pyrolyzed at about 500 to 600 ° C. in a shaft furnace type or fluidized bed type furnace together with iron oxides such as iron ore and iron dust. The carbon-containing materials such as tar and soot produced as a by-product of the thermal decomposition of organic waste are attached to the iron oxide, and then the iron oxide to which the carbon-containing material is attached in the high temperature region in the same furnace. Reduction to produce hot metal or solid reduced iron.

  In the example of Patent Document 4, organic waste such as biomass is pyrolyzed and gasified at a reaction temperature of about 600 ° C. to 700 ° C. together with iron-containing particles such as iron ore and pickled sludge in a fluid bed type furnace. The carbon-containing substances such as tar, char, and coke generated are attached to the iron-containing particles, and the iron-containing particles to which the carbon-containing substances are attached are used as raw materials for an iron manufacturing plant such as a blast furnace and a sintering machine.

JP 2001-49263 A JP-A-9-202907 JP 2003-147419 A JP 2004-131642 A “Materials and Processes” Vol. 8, No4 (1995), P841, 2.3, 40th to 41st lines. “Materials and Processes” Vol. 8, No 4 (1995), P864, FIG. 1

  However, as a problem of the method of attaching the carbon-containing substance of the existing organic waste such as Patent Documents 3 and 4 to the iron-containing particles, for example, the existing methods described in Patent Documents 3 and 4 etc. So, organic waste and iron-containing particles are charged together in the same reactor to pyrolyze and gasify the organic waste, so it is generated by pyrolysis and gasification of the organic waste. The temperature difference between the tar-containing gas and the iron-containing particles is small in principle, and the vapor-phase tar component in the generated tar-containing gas is difficult to be adsorbed or condensed on the iron-containing particles.

  In addition, as a problem of the existing method using a shaft furnace system in the reactor, when a large amount of plastic is charged together with iron-containing particles from the top of the shaft furnace, the plastic that has been heated in the furnace is softened and melted. Because troubles such as air permeability obstruction, gas drift, and shelves are likely to occur, stable operation is difficult.To ensure stable operation, after pre-granulating a mixture of plastic and iron-containing particles, A device such as charging in a shaft furnace is required, and a heavy pretreatment process is required.

  Furthermore, as another problem of the method of attaching carbon-containing substances of existing organic wastes such as Patent Documents 3 and 4 to iron-containing particles, it is difficult to apply them to iron ores containing hydrous iron oxide. Is mentioned.

  Conventionally, high quality hematite-type iron ore has been used as a raw material for iron ore in the iron making process. However, since the depletion of high-quality ore has been progressing in recent years, establishment of technology for expanding the use of inferior ore is required. Among them, the use of hydrous iron-containing iron ores, such as maramamba ore and pisolite ore, containing goethite, which is hydrous iron, as one of the main components and containing about 3% by mass or more of crystal water. There is a need for expansion technology.

  However, the method of attaching the carbon-containing material of the existing organic waste to the iron-containing particles needs to maintain the atmospheric temperature in the furnace above the thermal decomposition temperature of the organic waste (about 500 to 600 ° C. or higher). On the other hand, when the hydrous iron-containing iron ore becomes a temperature atmosphere of about 250 ° C. or higher, the desorption of crystal water proceeds, and the ore from which the crystal water has desorbed is reduced in strength and pulverized. When it becomes easy, when the lump ore of hydrous iron-containing iron ore is charged into a high-temperature furnace such as a shaft furnace type using existing methods such as Patent Documents 3 and 4, lump in the furnace Crystallized water in the ore is desorbed and the lump ore is pulverized, making it difficult to use the lump ore after treatment directly in the blast furnace.

  Accordingly, the present invention provides a method and apparatus for impregnating a tar with an iron oxide-containing solid material that can efficiently retain the carbon-containing material of organic waste in the iron oxide-containing solid material such as iron ore and pellets. The purpose is to do.

  Furthermore, in a preferred embodiment of the present invention, even when the iron oxide-containing solid substance is a hydrous iron oxide-containing iron ore, the carbon-containing substance of the organic waste is efficiently retained, and the hydrous iron oxide-containing iron ore shaft is retained. An object of the present invention is to provide a tar impregnation method and a tar impregnation apparatus for an iron oxide-containing solid substance, which can suppress powdering in the furnace and obtain a lump ore that can be charged into a blast furnace.

  The present inventors diligently studied a method for efficiently retaining a carbon-containing material of organic waste in a stable operation in an iron oxide-containing solid material such as iron ore or pellets.

  As a result, a pyrolysis gas containing a tar component generated by pyrolyzing organic waste such as waste plastic is transferred to the moving bed reactor containing the solid material containing iron oxide. And introducing the iron oxide-containing solid substance from the upper part of the moving bed reactor, and the pyrolysis gas containing the tar component and the iron oxide-containing solid substance in the moving bed reactor. The iron oxide-containing solid substance in the moving bed reactor is brought into contact with a counter-current flow, and a temperature gradient is provided in the height direction. By increasing the temperature of the solid material, it is possible to efficiently maintain the carbon-containing material of the organic waste in the iron oxide-containing solid material by expressing the effects 1) to 3) below. I found.

1) High dispersion action of tar in the pyrolysis gas to the packed bed of iron oxide-containing solid material in the reactor High-temperature pyrolysis gas introduced from the lower part of the moving bed reactor rises in the reactor, The heat is removed by the iron oxide-containing solid material layer in the reactor, and the gas temperature gradually decreases, and the tar content in the pyrolysis gas condenses sequentially from the high-boiling tar fraction as the gas temperature decreases, It is retained in the iron oxide-containing solid material layer.

  At this time, since the iron oxide-containing solid material layer in the moving bed reactor has a temperature gradient in the height direction, the tar content in the pyrolysis gas condenses all at once, and some iron oxide-containing solid material However, it is highly dispersed throughout the moving bed reactor and is efficiently retained in the iron oxide-containing solid material.

2) Stable retention by high-boiling tar adhering to iron oxide-containing solid substance adhering to high-boiling tar The iron oxide-containing solid substance adsorbed and condensed by the high-boiling tar content in the lower layer of the moving bed reactor falls in the reactor. When the ore is heated, the adsorbed / condensed tar is reheated and a coking reaction accompanied by gas generation such as dehydrogenation and side chain desorption occurs, resulting in heavy tar and carbonization. The tar content is stably retained in the iron oxide-containing solid material.

3) Iron oxide-containing solid substance adhering to the low-boiling point tar content of the iron oxide-containing solid substance. When descending the reactor, as the ore temperature rises, the adsorbed and condensed tar content re-evaporates, and the re-vaporized tar content rises in the reactor along with the pyrolysis gas, It is trapped again by the low-temperature iron oxide-containing solid material layer in the upper part of the reaction tube, and descends with the iron oxide-containing solid material.

  The tar content that has fallen together with the iron oxide-containing solid material is heated and vaporized again, and the condensation / vaporization cycle of the tar content in the reactor is repeated to generate tar circulation and promote high dispersion of the tar content. .

  Furthermore, the low-boiling point tar cyclization / condensation progresses during the tar circulation process in the reactor, and the low-boiling point tar becomes heavy and does not re-evaporate even when heated. By changing to a tar component that is stably held in the substance, the proportion of tar that can be held in the iron oxide-containing solid substance increases.

  The present invention has been proposed to solve the above-mentioned problems based on the above findings, and the gist thereof is as shown in the following (1) to (12).

  (1) In the first invention, a moving bed type reactor is charged with an iron oxide-containing solid substance from above, filled inside, discharged from the bottom, dry distillation, direct contact with a high-temperature medium, oxygen The tar-containing gas generated by treating organic waste with partial combustion with contained gas or at least one of steam reforming with oxygen-containing gas and steam is introduced from the lower part to raise the inside, and from the upper part. By exhausting, in the moving bed reactor, the tar-containing gas and the iron oxide-containing solid substance are brought into contact with each other in a counter flow, and the tar in the tar-containing gas is brought into contact with the iron oxide-containing solid substance. A method for impregnating an iron oxide-containing solid material with an iron oxide-containing solid material, which is impregnated and recovering the iron oxide-containing solid material impregnated with the tar content discharged from the bottom,

  (2) The second invention is the method of impregnating a solid substance containing iron oxide as described in (1), wherein the solid substance containing iron oxide is charged into the moving bed type reactor from above and filled inside. And discharged from the bottom, and produced by treating organic waste with dry distillation, direct contact with a high-temperature medium, partial combustion with an oxygen-containing gas, or steam reforming with an oxygen-containing gas and steam The tar-containing gas is introduced from the lower part, raised inside, and exhausted from the upper part, so that the tar-containing gas and the iron oxide-containing solid substance are brought into contact with each other in a counter flow in the moving bed reactor. The iron oxide-containing solid material is impregnated with tar in the tar-containing gas, and a temperature gradient in the height direction is provided to the iron oxide-containing solid material filled in the moving bed reactor. In the moving layer The iron oxide-containing solid substance temperature in the lower part of the moving bed is higher than the iron oxide-containing solid substance temperature in the moving part, and the iron oxide-containing solid substance temperature discharged from the bottom of the moving bed reactor is changed to a moving bed. Holding the tar impregnated in the iron oxide-containing solid material at a temperature lower than the temperature of the tar-containing gas introduced from the lower part of the mold reactor, and the iron oxide-containing solid material impregnated with the tar content discharged from the bottom It is characterized by collect | recovering.

  (3) A third invention is the method of impregnating a solid material containing iron oxide according to the above (1) or (2), wherein the solid material containing iron oxide is iron ore containing hydrous iron oxide, and the transfer The temperature of the hydrous iron-containing iron ore charged in the layer reactor is set to be lower than the crystal water decomposition temperature in the hydrous iron-containing iron ore.

  (4) A fourth invention is the method of impregnating iron oxide-containing solid material according to (3), wherein the temperature of the iron oxide-containing solid material retaining the tar content recovered from the moving bed reactor is set as follows: The temperature is higher than the crystal water decomposition temperature of the high hydrous iron-containing iron ore.

  (5) A fifth invention is the method for impregnating a solid substance containing iron oxide according to the above (3) or (4), wherein the iron oxide-containing iron ore containing at least one of pisolite ore and maramamba ore is used. It is characterized by being.

  (6) A sixth aspect of the present invention is the method for impregnating iron oxide-containing solid material according to any one of (1) to (5), wherein the iron oxide-containing solid material retains the tar discharged from the bottom. Is cooled using a heat exchanger, recovered after extracting the sensible heat, and preheated with the extracted sensible heat the solid material containing iron oxide charged into the moving bed reactor. Features.

  (7) According to a seventh invention, in the tar impregnation method for the iron oxide-containing solid substance according to any one of (1) to (6), the organic waste is defined by a container packaging recycling law. "Other plastic containers and packaging".

  (8) 8th invention utilizes the iron oxide containing solid substance collect | recovered with the tar impregnation method to the iron oxide containing solid substance in any one of said (1)-(7) as an iron-making process blast furnace raw material. It is a method for using a tar-impregnated iron oxide-containing solid substance in a blast furnace.

  (9) The ninth invention relates to the tar-containing gas discharged from the upper part of the moving bed reactor used in the method of impregnating the iron oxide-containing solid substance according to any one of (1) to (7), It is characterized by being a method of using a tar-containing gas in which the refined gas is used as a by-product gas substitute for the steelworks after purification.

  (10) In a tenth aspect of the invention, the tar-containing gas discharged from the upper part of the moving bed reactor used in the method of impregnating the iron oxide-containing solid substance according to any one of (1) to (7), After removing hydrochloric acid gas, it is introduced into a coke oven gas treatment process at an ironworks, and is a method of using a tar-containing gas used as a part of coke oven gas.

  (11) The eleventh invention relates to a tar-containing gas from organic waste by at least one of dry distillation, direct contact with a high-temperature medium, partial combustion with an oxygen-containing gas, or steam reforming with an oxygen-containing gas and steam. A tar-containing gas production apparatus for producing a solid substance, and an iron oxide-containing solid substance is charged from the top, filled inside and discharged from the bottom, and the tar-containing gas is introduced from the bottom to raise the inside and from the top A tar impregnation facility for iron oxide-containing solid material having a moving bed type reactor having a structure for exhausting.

  (12) The twelfth invention is the tar impregnation facility for the iron oxide-containing solid substance according to (11), wherein the iron oxide-containing solid substance discharged from the bottom of the moving bed reactor is cooled, The iron oxide-containing solid substance cooling device that recovers the retained sensible heat and the iron oxide-containing solid substance charged in the moving bed reactor are dried by the sensible heat collected by the iron oxide-containing solid substance cooling device. And an iron oxide-containing solid substance preheating device for preheating.

  Drawing 1 is a figure showing an example of the equipment composition for carrying out the pretreatment method and pretreatment device of the iron oxide content solid substance of the present invention concerning the 1st embodiment.

  Tar-containing gas based on at least one of dry plastic, direct contact with high-temperature medium, partial combustion with oxygen-containing gas, oxygen-containing gas and steam reforming with steam using waste plastic as organic waste A tar-containing gas 3 containing a gaseous tar content is generated by charging the generator 2.

  The necessary function of the tar-containing gas generation furnace 2 is to cause a reaction such as a thermal decomposition reaction, partial oxidation reaction, steam reforming reaction, etc. of organic waste in the furnace to cut the polymer bond of the organic waste. There is no particular limitation on the system as long as it satisfies the above functions.

  In addition, in order to obtain the tar-containing gas by breaking the polymer bond of the organic waste, about 400 ° C. or higher is necessary as the reaction temperature condition.

  For the dry distillation method, for example, an existing method such as an external heat kiln furnace can be applied. For the direct contact method with a high temperature medium, for example, a flow using a high temperature fluidized gas or a fluidized medium is used. Existing methods such as a laminar furnace can be applied. For the partial combustion method using an oxygen-containing gas, for example, a fluidized bed furnace using an oxygen-containing gas as a fluidizing gas or an organic waste together with an oxygen-containing gas. Existing methods such as a spouted bed furnace for blowing in can be applied.

  Regarding the steam reforming method using oxygen-containing gas and steam, the existing method of directly charging organic waste together with oxygen-containing gas and steam into a spouted bed furnace, etc. An existing system in which a pyrolysis gas obtained by direct contact and partial combustion with an oxygen-containing gas is introduced into the reforming furnace together with the oxygen-containing gas and water vapor is applicable.

  The tar-containing gas 3 generated in the tar-containing gas generation furnace 2 is introduced into the vertical moving bed reactor 5 charged with the iron oxide-containing solid substance from the lower part of the moving bed reactor 5 to move the moving bed. The iron oxide-containing solid substance 6 in the type reactor 5 is brought into contact with the iron oxide-containing solid substance in a counter flow, and after contact with the iron oxide-containing solid substance, the tar-containing gas 8 is exhausted from the upper part of the moving bed type reactor 5.

  Here, the introduction position of the tar-containing gas 3 to the moving bed reactor 5 and the exhaust position of the tar-containing gas 8 after contact with the iron oxide-containing solid substance are oxidized in the moving bed reactor 5. There is no particular limitation as long as the iron-containing solid substance 6 and the tar-containing gas 3 can be brought into contact with each other in a counterflow.

  For the introduction position of the tar-containing gas 3, for example, selection of the lower side surface of the moving bed type reactor 5 as shown in FIG. 2 or selection near the furnace bottom of the moving bed type reactor 5 as shown in FIG. Is possible. Regarding the exhaust position of the tar-containing gas 8 after contacting the iron oxide-containing solid substance, for example, selection of the upper side surface of the moving bed type reactor 5 as shown in FIGS. 2 and 3, or for example, a moving bed type as shown in FIG. The vicinity of the top of the furnace of the reactor 5 can be selected.

  The iron oxide-containing solid material 6 in the moving bed reactor 5 is provided with a temperature gradient in the height direction of the moving bed, so that the oxidation in the lower part in the moving bed is higher than the iron oxide-containing solid substance temperature in the upper part in the moving bed. The temperature of the iron-containing solid substance is increased.

  The high-temperature tar-containing gas 3 introduced at the lower part of the moving bed type reactor 5 has a temperature of about 500 to 900 ° C., and rises in the moving bed type reactor 5 (see B in the figure). The heat is removed by the iron oxide-containing solid material layer whose temperature is lower than that, and the gas temperature gradually decreases, and the tar content in the tar-containing gas 3 is sequentially condensed from the high-boiling tar fraction as the gas temperature decreases. Then, it moves to the iron oxide-containing solid material layer and is retained in the ore.

  At this time, since the iron oxide-containing solid material layer in the moving bed type reactor 5 is provided with a temperature gradient in the height direction, the tar content in the pyrolysis gas 3 is condensed at once, and some iron oxide is condensed. Without being biased to be contained only in the contained solid substance, it is highly dispersed throughout the moving bed reactor 5 and tar can be efficiently retained in the iron oxide-containing solid substance.

  When the iron oxide-containing solid material impregnated with the high-boiling tar content in the lower layer portion in the moving bed reactor 5 is lowered in the moving bed reactor 5, the temperature of the iron oxide-containing solid material rises, The tar content is reheated, and a coking reaction accompanied by gas generation such as dehydrogenation and side chain group elimination occurs in the lower layer of the moving bed reactor 5 and the tar content becomes heavier and carbonized. In addition, the carbon content is further stabilized in the iron oxide-containing solid material.

  The iron oxide-containing solid material impregnated with the low-boiling-point tar content in the upper part of the moving bed reactor 5 is lowered when the inside of the moving bed reactor 5 is lowered (see A in the figure). As the temperature rises, the tar content is re-vaporized, and the re-vaporized tar content is accompanied by the pyrolysis gas 3 and rises in the moving bed reactor 5. The layer is again trapped and impregnated into the iron oxide-containing solid material and descends with the iron oxide-containing solid material.

  The tar content impregnated in the iron oxide-containing solid substance and then dropped is heated and vaporized again, and the condensation and vaporization cycle of the tar content is repeated in the moving bed reactor 5 to generate tar circulation. High dispersion of tar content in the moving bed reactor is promoted.

  Further, in the tar circulation process in the moving bed type reactor 5, the reaction such as cyclization / condensation of the low boiling point tar proceeds, the low boiling point tar becomes heavy, and the low content in the iron oxide-containing solid substance is reduced. The boiling-point tar content changes to a tar component that does not re-volatilize even when heated, and the proportion of tar that is stably held in the ore increases.

  As a kind of the iron oxide-containing solid material charged into the moving bed reactor 5, iron ore, pellets containing iron oxide, or the like can be applied. Further, regarding the particle size of the iron oxide-containing solid substance charged into the moving bed reactor 5, if the particle size is too small, the gas permeability of the tar-containing gas is deteriorated and the operation stability is lowered. It is desirable to set it to a degree or more.

  The post-treatment iron oxide-containing solid substance discharged from the moving bed reactor 5 can be used as a blast furnace raw material when an iron oxide-containing solid substance having a particle size of about 10 mm or more is used as a raw material. When using a solid material having a particle size of iron oxide as a raw material, it is preferably used as a raw material for a sintering machine. In either case, it becomes possible to reduce the amount of coke and the amount of coal used in the sintering machine and blast furnace.

  FIG. 5: is a figure which shows an example of the equipment structure for implementing the pre-processing method and pre-processing apparatus of the iron oxide containing solid substance of this invention which concern on 4th Embodiment. The tar-attached iron oxide-containing substance 7 is charged into the tar-attached iron oxide-containing solid substance cooling device 10 and cooled, and the tar-attached iron oxide-containing solid substance 11 after cooling is recovered and used as an iron-making raw material.

  The method of the tar-attached iron oxide-containing solid substance cooling device 10 is not particularly limited, and an existing direct heat exchange system or indirect heat exchange system heat exchanger can be applied. An example using a direct heat exchange type heat exchanger using nitrogen gas was shown.

  The tar-attached iron oxide-containing solid substance cooling device 10 is introduced with an iron oxide-containing solid substance cooling gas 12 to cool the tar-attached iron oxide-containing substance 7 and recover sensible heat, thereby obtaining a gas 13 after sensible heat recovery. . The iron oxide-containing solid substance 6 is charged into the iron oxide-containing solid substance preheating device 15, the recovered gas 13 is introduced into the iron oxide-containing solid substance preheating device 15, and the iron oxide-containing solid substance 6 is dried. Preheat.

  Further, as a new feature of the present invention that does not exist in the prior art, it is possible to improve the strength of the hydrous iron-containing iron ore. The hydrous iron-containing iron ore is an iron ore containing a large amount of goethite, which is hydrous iron oxide, and containing about 3% by mass or more of water of crystallization. Examples thereof include maramamba ore and pisolite ore.

  When iron ore containing hydrous iron oxide containing iron ore is charged into the blast furnace, the ore strength deteriorates due to crystallization water decomposition at the upper part of the blast furnace, and the ore is pulverized. It is widely known that increasing the amount of the use of the blast furnace hinders the air permeability in the blast furnace and causes problems such as unstable blast furnace operation and reduced productivity.

  In response to the above problems, the method of the present invention uses a lump ore of hydrous iron oxide-containing iron ore as the iron oxide-containing solid material to be charged into the moving bed reactor 5 and charged from the inlet of the moving bed reactor 5. By setting the temperature of the lump ore to be a temperature at which the crystal water in the lump ore is not decomposed and the temperature of the lump ore to be recovered from the outlet of the moving bed type reactor is equal to or higher than the crystal water decomposition temperature of the lump ore. In the reactor 5, while gradually proceeding with the water splitting reaction, iron ore is generated by adsorbing and condensing tar into the pores generated by the water splitting. Deterioration is suppressed.

  As described in Non-Patent Documents 1 and 2, for example, as described in Non-Patent Documents 1 and 2, it is known that the crystal water decomposition of hydrous iron-containing iron ore starts at about 250 ° C and is almost completed at about 350 ° C. Similar results were obtained in their measurements.

  Therefore, the temperature condition of the iron ore-containing iron ore lump ore charged from the inlet of the moving bed reactor 5 is preferably about 250 ° C. or less at which the crystal water is not decomposed, and the lump recovered from the outlet of the moving bed reactor 5 The temperature condition of the ore is preferably about 350 ° C. or higher at which crystallization water decomposes. The temperature at which the crystal water decomposes is preferably confirmed in advance by differential thermal analysis, thermogravimetric analysis, or the like.

  On the other hand, when the method of adhering carbon-containing substances of existing organic waste such as Patent Document 3 and Patent Document 4 to iron-containing particles is applied to lump ores of hydrous iron oxide-containing iron ores, Since the atmosphere temperature in the furnace needs to be about 500 ° C or higher, which is the thermal decomposition temperature of organic waste, ore powdering occurs in the furnace due to crystal water decomposition. It is difficult to produce possible massive ores.

  1 and 5 show examples in which waste plastic is used as organic waste, but in addition to waste plastic, for example, tar components are generated by a thermal decomposition reaction such as biomass and waste rubber. The present invention can be applied to any organic waste material.

Example 1
As an example 1, the equipment configuration shown in FIG. 5 is used, a volume Ripple is used as an organic waste, a particle size of φ1 to φ10 mm, a carbon content of less than 0.1% by mass, crystal water An example in which a hematite-type ore having a content of 2% by mass (hereinafter referred to as ore) is used and treated at a capacity of 100 tons / day for a rippler treatment scale and 1000 tons / day for an iron ore treatment scale is shown.

  The tar-containing gas generation furnace 2 uses an externally heated rotary kiln, and the iron oxide-containing solid substance preheating device 15 and the tar-impregnated iron oxide-containing solid substance cooling device 10 use heat of a direct heat exchange system using nitrogen gas as a heat medium. An exchanger was used.

  A moving bed type filled with ore and charged with tartar containing gas in a tar containing gas generating furnace, pyrolyzing the container ribpla to generate a tar containing gas with a gas temperature of about 650 ° C. It was introduced from the bottom of the reactor and brought into contact with the ore in the moving bed reactor in a counterflow.

  The ore was first dried by passing through an iron oxide-containing solid material preheating device, and preheated to about 150 ° C., and then charged into a moving bed reactor. The ore temperature in the moving bed reactor was about 150 ° C. near the top of the reactor and about 400 ° C. near the bottom of the reactor.

  The treated ore discharged from the moving bed reactor was recovered by passing through an iron oxide-containing solid material cooling device after impregnation with tar and cooling to 100 ° C. or lower with nitrogen gas. The sensible heat obtained by heat exchange between the treated ore and nitrogen gas in the iron oxide-containing solid material cooling device after tar impregnation was used for preheating the ore charged in the iron oxide-containing solid material preheating device.

The carbon content in the recovered ore was about 4% by mass on average, and according to the present invention, a large amount of the C content contained in the volume Lipra could be retained in the ore. Further, the variation range of the carbon content in the recovered ore is about 3 to 5% by mass, and according to the present invention, the tar content in the tar-containing gas is highly dispersed throughout the ore in the moving bed reactor, The tar content could be efficiently retained in the ore. In addition, the tar-containing gas after passing through the moving bed reactor was purified, and the obtained purified gas of about 3500 Nm ³ / hr was used as a substitute for the by-product gas of the ironworks.

(Comparative Example 1)
As Comparative Example 1, the method of Patent Document 4 in which organic waste is pyrolyzed and gasified at a reaction temperature of 650 ° C. together with iron ore in a fluidized bed reactor is used. In the same manner as in Example 1, as in Example 1, the volume of rippla was used, and in the same manner as in Example 1, the iron oxide-containing substance was a hematite ore (hereinafter referred to as ore) having a particle diameter of φ1 to φ10 mm. An example of processing at a processing scale of 150 t / day and an iron ore processing scale of 1000 t / day is shown.

  The carbon content in the ore discharged from the fluidized bed reactor is about 1% by mass or less, and the method of Comparative Example 1 has a small temperature difference between the tar-containing gas and the ore in principle. Since there is no tar circulation action in the reactor as in No. 1, the proportion of tar stably retained in the ore is reduced, and the carbon content in the volume of rippla can be efficiently transferred into the ore. There wasn't.

(Example 2)
As Example 2, the equipment configuration shown in FIG. 5 was used, a volumetric repulper was used as the organic waste, the particle size φ10 mm to φ30 mm, the crystal water content 8 mass%, the carbon content 0 as the iron oxide-containing substance. An example is shown in which hydrous iron-containing iron ore (hereinafter referred to as ore) mainly composed of less than 1% by mass of pisolite ore is treated at a volume repulling treatment scale of 150 t / day and an iron ore treatment scale of 1000 t / day.

  The tar-containing gas generation furnace 2 uses an externally heated rotary kiln, and the iron oxide-containing solid substance preheating device 15 and the tar-impregnated iron oxide-containing solid substance cooling device 10 use heat of a direct heat exchange system using nitrogen gas as a heat medium. An exchanger was used. The tar-containing gas generation furnace of the external heat type rotary kiln system is charged with the capacity Ripla, the capacity Ripla is pyrolyzed to generate a tar-containing gas having a gas temperature of about 650 ° C., and the generated tar-containing gas is It was introduced from the lower part of the moving bed reactor filled with ore and brought into contact with the ore in the moving bed reactor in countercurrent.

  The ore was first dried by passing through an iron oxide-containing solid material preheating device, and preheated to about 150 ° C., and then charged into a moving bed reactor. The hydrous iron-containing iron ore temperature in the moving bed reactor was about 150 ° C. near the top of the reactor and about 350 ° C. near the bottom of the reactor.

  The ore discharged from the moving bed reactor was recovered after passing through an iron oxide-containing solid substance cooling device after impregnation with tar and cooling to 100 ° C. or lower. The carbon content in the recovered ore was about 6% by mass on average, and according to the present invention, a large amount of C contained in the volume of rippla could be retained in the ore.

  Moreover, the variation range of the carbon content in the recovered ore is about 5 to 7% by mass, and the tar content in the tar-containing gas is the ore in the moving bed reactor according to the present invention, as in Example 1. Highly dispersed throughout, the tar content could be efficiently retained in the ore.

  Regarding the strength of the recovered treated ore, the reduced powder index RDI (JIS M 8720) of the ore decomposed by heating at 350 ° C. without treating with the tar-containing gas is about 50% (powder rate) The reduced powdering index (RDI) of the ore treated and recovered by the tar impregnation method of the present invention is about 30% (powder ratio of about 30%). The hydrous iron-containing iron ore could be modified into an ore having a level of strength that is not problematic for blast furnace use.

  In normal blast furnace operation, it is common to manage the reduced powdering index of the charged raw material at about 40% or less in order to avoid aeration inhibition due to in-furnace powdering.

  In addition, the ore layer was not suspended in the moving bed, and the ore was impregnated with tar under stable operation.

(Comparative Example 2)
As Comparative Example 2, organic waste is used in a moving bed type reactor in which organic waste is charged together with iron ore from the top of the reactor and pyrolyzed and gasified at a reaction temperature of 650 ° C. In the same manner as in Example 2, a volumetric Lipra was used, and as an iron oxide-containing substance, as in Example 2, a hydrous iron oxide mainly containing pisolite ore having a crystallization water content of 8% by mass and a particle diameter of φ10 mm to φ30 mm. An example in which the iron ore contained (hereinafter referred to as ore) is used and treated in the same manner as in Example 2 at a volume of Ripura treatment scale of 150 t / day and an iron ore treatment scale of 1000 t / day is shown.

  More than 50% of the iron ore recovered from the moving bed was pulverized. In the method of Comparative Example 2, the reason why the powdering ratio is large is that the method of Comparative Example 2 is that the ore and the volume Lipra are heated at the same time in the moving bed reactor, and the volume Lipra thermal decomposition temperature (400 It is considered that the ore from which the crystal water was decomposed was pulverized in the moving bed before tar deposition occurred because the crystal water decomposition temperature of iron ore was lower than that of about ~ 500 ° C). .

  Moreover, the method of the comparative example 2 produced the gas drift and shelf suspension in a moving bed furnace, and became the operation result with low stability.

It is a figure showing the example of equipment of the device concerning the 1st invention of the present invention. It is a figure which shows the example of the introduction position of the tar containing gas of the apparatus which concerns on 1st invention of this invention, and the exhaust position of the tar containing gas after an iron oxide containing solid substance contact. It is a figure which shows another example of the introduction position of the tar containing gas of the apparatus which concerns on 1st invention of this invention, and the exhaust position of tar containing gas after iron oxide containing solid substance contact. It is a figure which shows another example of the introduction position of the tar containing gas of the apparatus which concerns on 1st invention of this invention, and the exhaust position of tar containing gas after iron oxide containing solid substance contact. It is a figure which shows the equipment example of the apparatus which concerns on the 4th invention of this invention.

Explanation of symbols

1 Raw material waste plastic 2 Tar-containing gas generating furnace 3 Tar-containing gas 4 Incombustibles, ash 5 Moving bed reactor 6 Iron oxide-containing solid material 7 Iron oxide-containing solid material after treatment 8 Tar-containing gas after contact with iron oxide-containing solid material 9 Iron oxide-containing solid substance after drying and preheating 10 Iron oxide-containing solid substance cooling device after tar impregnation 11 Iron oxide-containing solid substance after tar impregnation after cooling 12 Iron oxide-containing solid substance cooling gas 13 Gas after sensible heat recovery 14 Iron oxide Exhaust gas after preheating containing solid material 15 Iron oxide containing solid material preheating device A Flow of iron oxide containing solid material B Flow of tar containing gas

Claims (12)

  A moving bed type reactor is charged with iron oxide-containing solid material from the top, filled inside, discharged from the bottom, dry distillation, direct contact with a hot medium, partial combustion with oxygen-containing gas, or oxygen By introducing a tar-containing gas generated by treating organic waste with at least one of the gas reforming and the steam reforming with water vapor from the lower part, raising the inside, and exhausting from the upper part, the moving bed type In the reactor, the tar-containing gas and the iron oxide-containing solid substance are brought into contact with each other in a counter flow, the iron oxide-containing solid substance is impregnated with the tar in the tar-containing gas, and discharged from the bottom. A method of impregnating an iron oxide-containing solid substance with tar, wherein the iron oxide-containing solid substance impregnated with the tar content is recovered.   A moving bed type reactor is charged with iron oxide-containing solid material from the top, filled inside, discharged from the bottom, dry distillation, direct contact with a hot medium, partial combustion with oxygen-containing gas, or oxygen By introducing a tar-containing gas generated by treating organic waste with at least one of the gas reforming and the steam reforming with water vapor from the lower part, raising the inside, and exhausting from the upper part, the moving bed type In the reactor, the tar-containing gas and the iron oxide-containing solid substance are brought into contact with each other in a counter flow, and the iron oxide-containing solid substance is impregnated with the tar in the tar-containing gas. The iron oxide-containing solid substance filled in the reactor is provided with a temperature gradient in the height direction so that the iron oxide-containing solid in the lower part in the moving bed is lower than the iron oxide-containing solid substance temperature in the upper part in the moving bed. High material temperature In addition, the iron oxide-containing solid material is impregnated so that the temperature of the iron oxide-containing solid material discharged from the bottom of the moving bed reactor is lower than the temperature of the tar-containing gas introduced from the lower portion of the moving bed reactor. A method for impregnating a solid substance containing iron oxide with a solid material, wherein the solid substance containing iron oxide impregnated with the tar content discharged from the bottom is recovered by holding the produced tar.   The iron oxide-containing solid substance is made of hydrous iron-containing iron ore, and the temperature of the hydrous iron-containing iron ore charged into the moving bed reactor is determined by the crystal water decomposition temperature in the hydrous iron-containing iron ore. The method for impregnating a solid substance containing iron oxide with tar according to claim 1 or 2, characterized in that the content is less than 1.   The oxidation according to claim 3, wherein the temperature of the iron oxide-containing solid substance retaining the tar content recovered from the moving bed reactor is equal to or higher than the crystal water decomposition temperature of the hydrous iron-containing iron ore. Tar impregnation method for iron-containing solid material.   5. The method for impregnating a solid substance containing iron oxide according to claim 3, wherein the hydrous iron-containing iron ore is at least one of a pisolite ore and a maramamba ore.   The iron oxide-containing solid substance holding the tar discharged from the bottom is cooled using a heat exchanger, recovered after extracting sensible heat, and using the extracted sensible heat, the moving bed reaction The method for impregnating a solid substance containing iron oxide with tar according to any one of claims 1 to 5, wherein the iron oxide-containing solid substance charged in the vessel is preheated.   The method for impregnating a solid substance containing iron oxide according to any one of claims 1 to 6, wherein the organic waste is "other plastic container and packaging" defined by the Container and Packaging Recycling Law.   The iron-containing solid substance recovered by the tar impregnation method for the iron oxide-containing solid substance according to any one of claims 1 to 7 is used as a raw material for a steelmaking process blast furnace. How to use for blast furnace.   The refined gas is refined from the upper part of the moving bed reactor used in the tar impregnation method for the iron oxide-containing solid substance according to any one of claims 1 to 7, and the refined gas is then used as a by-product gas of the ironworks. A method of using a tar-containing gas characterized by being used as an alternative.   Coke oven gas treatment of ironworks after removing the hydrochloric acid gas from the tar-containing gas discharged from the top of the moving bed reactor used in the method of impregnating the iron oxide-containing solid substance according to any one of claims 1 to 7 A method for using a tar-containing gas, which is introduced into a process and used as a part of coke oven gas.   A tar-containing gas production apparatus for producing a tar-containing gas from organic waste by at least one of dry distillation, direct contact with a high-temperature medium, partial combustion with an oxygen-containing gas, or steam reforming with an oxygen-containing gas and steam; A moving bed type having a structure in which an iron oxide-containing solid substance is charged from the top, filled inside and discharged from the bottom, and the tar-containing gas is introduced from the bottom to raise the inside and exhaust from the top A facility for impregnating tar with iron oxide-containing solid material, comprising a reactor.   An iron oxide-containing solid material cooling device of a heat exchange system that cools the iron oxide-containing solid material discharged from the bottom of the moving bed reactor and recovers retained sensible heat, and the iron oxide-containing solid material cooling device The oxidation according to claim 11, further comprising an iron oxide-containing solid material preheating device for drying and preheating the iron oxide-containing solid material charged into the moving bed reactor with the sensible heat recovered in step 1. Tar impregnation equipment for iron-containing solid materials.

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