A substitute product for coke used in metallurgical shaft furnaces and its application method

Abstract

The present invention discloses a coke substitute product for a metallurgical vertical furnace and an application method thereof, and belongs to the field of metallurgical technology. The present invention produces a metallurgical coke substitute product with high strength, high durability and certain sealing properties by pressurizing and encapsulating a mixture of fossil and / or biological carbon-rich materials used for coking into carbon in a single miniature steel container serving as a carbonization chamber and a protective shell. When in use, the product is directly added to the vertical furnace along with other furnace charges, and during the downward process, the heat energy in the furnace is used to dry and distill the internal materials and form a carbonized body, and after the steel shell is dissolved, melted or broken, it participates in the furnace reaction and carburizes the molten iron, and finally supports the material column at the bottom of the vertical furnace. Under the condition that carbon-rich blocks are directly added to the charge to compensate for the carbon required for the carbon gasification reaction, the present invention can achieve all or most of the coke substitution, and at the same time, it can completely get rid of the dependence on coking coal required by the prior art.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgy, and more particularly to a substitute product for coke used in a metallurgical shaft furnace and an application method thereof. Background Art

[0002] Metallurgical shaft furnaces that use coke are mainly smelting blast furnaces and casting ironmaking furnaces that reduce iron, manganese, chromium or nickel oxides and their associated minerals at high temperatures, especially blast furnaces that account for a large proportion of pig iron used in steelmaking in the world today. The dependence of metallurgical shaft furnaces on coke is mainly due to its loose skeleton effect of good air and liquid permeability for the shaft furnace charge column support and good reactivity. In particular, the trend of large-scale and ultra-large-scale iron-making blast furnaces has further improved and tightened the indicators of required coke. So far, in order to ensure the use requirements of the loose skeleton of coke in the shaft furnace, reduce the mechanical wear and tear of large coke during the turnover and transportation process, ensure that the coke in the middle of the shaft furnace does not deteriorate significantly due to the reaction, affect the permeability of the material column and the strength of coke, and maximize the indirect reduction of iron oxides and maximize the coal injection, many stringent and contradictory requirements need to be reflected in the performance indicators of coke products. In addition, due to the constraints of the existing coking technology itself, all the focus issues can only be achieved through the cumbersome and complex coking process of limited coal types and strict coking control, which makes the prices of a few major coking coal types suitable for the production of metallurgical shaft furnace coke high, and the cost of coke entering the furnace continues to rise with the reduction of coking coal resources, the increase of logistics costs and the stricter environmental protection requirements. In addition, coking requires long-term dry distillation and carbonization under the indirect closed heating conditions of the coke furnace, and then quenching and screening to produce shaft furnace coke. The pollution, material consumption and energy consumption of its production process are very considerable.

[0003] Since the shaft furnace is a relatively high-efficiency and energy-saving iron ore smelting reactor and foundry ironmaking furnace that must use coke, iron smelters have been making every effort to reduce the coke ratio in the smelting process and try to eliminate the dependence on coke for a long time. Although great progress has been made (such as the popularization of blast furnace oxygen-enriched coal injection technology, etc.), coke is still the main reducing agent and fuel of the shaft furnace in general, and is indispensable as a loose skeleton supporting the upper material column and permeable to air and liquid. So far, there has been no replacement product for shaft furnace coke that basically gets rid of the coking process and the technology for its production and use. Summary of the invention

[0004] 1. Problem to be solved

[0005] The purpose of the present invention is to replace the existing coke, fundamentally solve the serious dependence of metallurgical shaft furnaces on coke and even coking coal, expand the types of carbon-rich materials available in the shaft furnace, further utilize the waste heat of shaft furnace flue gas, and significantly reduce the number of coke ovens, energy consumption and total carbon dioxide emissions.

[0006] 2. Technical solution

[0007] The main functions and effects of coke used in vertical furnace smelting are: (1) as a fuel for heating the charge; (2) as a reducing agent for metal oxide ores; (3) as a recarburizer to reduce the melting point of the reduced metal liquid; (4) as a loose skeleton to support the charge column of the vertical furnace. For modern blast furnaces, due to the increasing coal injection ratio and the popularity of oxygen-enriched and high-temperature winds, the fuel function of coke tends to weaken. The role of coke as a recarburizer and reducing agent can also be reflected in the function of coke in supporting the charge column. It can be said that the core function and irreplaceable role of coke is to support the charge column and the loose skeleton that is permeable to air and liquid. In addition, the loose skeleton function and effect of coke can only be exerted and reflected when the coke descends from the top of the furnace to the lower part of the vertical furnace. That is to say, its performance must undergo a series of degradation caused by its own physical and chemical changes and degradation caused by various physical and chemical factors caused by environmental influences. In order to better become the final loose skeleton that supports the charge column and is permeable to air and liquid, the coke body must have sufficient ability to resist various degradation effects.

[0008] In summary, as a direct substitute for coke, the function and role of the loose skeleton supporting the charge and being breathable and liquid-permeable are the key points in product design and process design. It must have suitable density (porosity), timely and appropriate reactivity, sufficient high-temperature strength, suitable decomposition temperature of hydrocarbon reducing gas, etc., as well as the original shape and size of the product to complete the carbonization as the charge goes down.

[0009] In order to solve the above-mentioned problems, focus on the core function of coke and take into account the auxiliary function of coke, the technical solution adopted by the present invention is: after the carbon-rich material is mixed with the additives, it is pressurized and packaged in a single miniature steel container as a carbonization chamber and a protective shell to produce a metallurgical coke substitute product with high strength, high durability and certain sealing. The substitute is added to the vertical furnace along with other top-loaded furnace materials. During the downward process, the heat energy in the furnace is used to dry and distill the internal materials and form a carbonized body under the pressure in the furnace. After the outer shell is dissolved, melted or broken, it participates in the reaction in the furnace and carburizes the molten iron, and finally supports the material column at the bottom of the vertical furnace. By designing the shape, size, thickness, outer shell wall thickness and internal material ratio of the container, the carbonization time, reaction time, reaction specific surface area, permeability and density, strength and block size of the carbonized body required for the internal material can be obtained. By directly adding carbon-rich blocks into the charge to compensate for the carbon required for the carbon gasification reaction, all or most of the coke can be replaced. At the same time, it can also partially or completely replace the coking coal required by the prior art, and further reduce the number of coke ovens.

[0010] The main factors to be considered in the specific design of the product and application method of the present invention are as follows:

[0011] 1) Carbon steel sheet is used as the outer shell of the product. Its functions are: (1) As a strong and sealed container for carbon-rich materials, it is not necessary to add any binder and dry it for molding and obtaining cold strength; (2) Good plasticity makes the product easy to process and shape after filling the material to obtain the ideal material stacking density in the furnace; (3) Excellent mechanical properties facilitate the pressurization and compaction of the internal materials of the product; (4) Good thermal conductivity can introduce the heat of the air flow in real time; (5) As a carbonization chamber, it keeps the internal materials well sealed during the carbonization process; (6) The high-strength outer shell enables the product to resist the impact of the logistics process before entering the vertical furnace and when entering the furnace, and withstand the squeeze between the materials in the block belt area in the furnace (7) The sealed shell can resist the erosion of gases such as alkaline oxides in the block zone and the soft melt zone. (8) Due to the high-strength steel shell's wrapping and the increased volume due to the rounded cross section, a large volume expansion is allowed in the early stage of the coking process. (9) The steel shell gradually softens as the temperature rises. During the closed carbonization process, the gas pressure in the furnace and the static pressure of the material column can be transmitted to the interior, dynamically compensating for the shrinkage of the semi-coke and increasing the density of the carbonized body. (10) The steel shell can dissolve and rupture in time with corrosion, carburization and high temperature, releasing the carbonized body to participate in the metallurgical reaction and combustion reaction in the furnace. (11) The steel shell can eventually fully enter the molten metal and become the product of the process it serves.

[0012] 2) Determination of the product's outer shape and size. (1) The main considerations for determining the product's shape and outer size are the time required for the internal material to be fully sealed for carbonization, the impact on the overall permeability of the charge, the reaction specific surface area of ​​the carbonized body, degradation, and the particle size that serves as the skeleton after the reaction. (2) For different metallurgical vertical furnaces, the product's outer dimensions, shape, and shell wall thickness can be optimized and designed in a targeted manner and used in combination. The cupola furnace should choose a product outer dimension that is much larger than that of the blast furnace. (3) The maximum value of the relatively smallest thickness dimension in three dimensions determines the process time of coking and carbonization of the carbonized block. When the thickness dimension is large, the internal material can accommodate more material, and the weight of the internal material is higher than the weight of the outer shell steel plate (that is, the steel plate is relatively (1) The thickness of the product contour should be as large as possible under the premise that the carbonization is sufficient to meet the needs of the vertical furnace; (2) The product is subjected to greater forces due to the squeezing and rubbing of the material during the carbonization process in the vertical furnace, and there are also requirements for the length of closed protection required for sufficient carbonization. The length-to-thickness ratio of the product contour should not be too large to maintain rigidity; (3) In order to avoid flat contact between products, it is better to choose more curved surfaces to increase the gap between materials in the furnace and improve air permeability. However, a certain plane is also required to maintain the stability of the product to ensure that it does not roll during transportation; (4) In order to improve the gas-liquid permeability in the furnace, grooves or convex ribs can be set on the product contour.

[0013] 3) Determination of the wall thickness of the carbon steel sheet shell of the product. (1) The determination of the wall thickness of the carbon steel sheet shell of the product mainly considers the factors such as the appropriate rigidity, strength, crack resistance and timely dissolution and melting of the single container, and is also closely related to the volume (size) of the single container; (2) If the shell wall is too thick, the shell weight ratio of the shell to the internal material is high, the cost of the product is also high, and the shell breaks too late, which affects the timeliness of the reaction in the furnace; (3) If the shell wall is too thin, the product may be damaged during the sealing and logistics process, and the product may be deformed or broken before it is fully carbonized in the vertical furnace, which may cause the carbonized body to have low density, poor strength, rapid deterioration, and easy breakage, and will also affect the air and liquid permeability. ; (4) The outer dimensions of the product are large, so the corresponding outer shell should be slightly thicker to ensure rigidity and strength; (5) The wall thickness of the steel outer shell must also meet the requirements of ensuring the sealing of solid materials inside the product during the logistics process. The degree of sealing also takes into account the smooth discharge of internal gas and the exchange of internal and external airflow during the drying and distillation process after the vertical furnace is heated; (6) When different product production and processing methods are used, the wall thickness of the initial raw material thin plate steel strip is very different. If the raw material thickness of the direct wrapping carbon-rich material processing method is used, the product steel outer shell thickness is much smaller than the raw material thickness if the stretching method is used to form a carbon-rich material containing cavity. The actual container processing raw material thin plate used can be selected in the range of 0.1-0.5mm, which is the thickness value of the first series of thin plate standards that are easily purchased in the market. The wall thickness of the steel outer shell of the processed product may be 0.06-0.40mm.

[0014] 4) The main process of product processing and manufacturing is: forming the outer shell container, filling the container with carbon-rich material, pressurizing and compacting the carbon-rich material in the container, sealing the container and pre-shell or subsequent individual cutting of the filling body. According to the differences in manufacturing technology and equipment, the order of the above process steps can be adjusted to a certain extent.

[0015] 5) Selection and state of carbon-rich materials. Based on the existing coke coal blending theory and practice, it is possible to relatively reduce and completely save the use of scarce and high-utilization-value coals, increase the use of readily available and common coals, and especially directly use some unprocessed biomass and recycled waste carbon-rich materials for co-carbonization. The feasibility is based on the following: (1) Since the carbonization is completed directly in the vertical furnace under protective conditions, the selection of the carbon-rich material only needs to consider the performance of the final carbonized body of the product in the vertical furnace; (2) Since the carbonization is directly carried out in the vertical furnace, the higher furnace pressure and slow heating rate have a certain inhibitory effect on gasification, and the cooling of the upper charge will cause some of the gasified components to condense on the charge surface, and the gasification ratio will decrease when heated. Compared with the coke oven as a whole, the total amount of viscous material (heated liquefied material) used for coking of the same carbon-rich material increases, which has the effect of promoting the carbonization rate; (3) The viscous material produced during carbonization is a key factor in the formation of the carbonized body and its high-temperature characteristics. Its total amount and type vary with the ratio of the carbon-rich material. The high-temperature characteristics of the carbonized body under a specific ratio can be conveniently obtained through experiments based on the materials used and their particle size distribution; (4) Since the vertical furnace does not have the function of recovering the gas and liquefied chemical products of the carbon-rich material in the product during the carbonization process, the amount of carbon-rich material added should be reduced as much as possible under the premise that the total amount of viscous material produced meets the high-temperature strength of the carbonized body. The total volatile matter of the material is increased, and the amount of high-carbon content coal (such as anthracite, etc.) is increased; (5) When the product is made, the use of the steel shell allows the internal material to be compacted under very high pressure, achieving a much higher pressure than the existing coal pressing or coking coal tamping, which is beneficial to coking and carbonization and increasing the initial density of carbon-rich materials; (6) The use of the steel shell allows a large volume expansion in the early stage of the carbonization process, which is widely adaptable to the expansion of carbon-rich materials, and can use high-expansion coal that cannot be used in coking ovens; (7) The entire coking and carbonization process is The carbonization is completed under the top pressure in the furnace and the static pressure of the material column, which can maintain a relatively high density of the carbonized body and make it possible to directly use high-volatile biomass; (8) Due to the static pressure of the furnace charge, the density of the carbonized body finally formed by the same material can be greater than that of the existing coke, and the addition of biomass or recycled carbon materials can obtain the appropriate density of the carbonized body that takes into account the various reactions in the furnace; (9) The maximum particle size of the carbon-rich material after crushing is no more than 4 mm, and the particle size grading (particle size distribution) can be slightly looser than the existing technical standards for coking coal blending.

[0016] 6) Compensation of heat required for carbonization of carbon-rich materials. Since the carbon-rich materials that replace coke are completely carbonized in the vertical furnace, the heat required for evaporation, dry distillation and carbonization of the components in the carbon-rich materials needs to be balanced by adding additional fuel through heat balance calculation in combination with the total volatility ratio, carbonization rate, etc. Since the total volatile gas volume of the material (including water content and the amount of gasification that can be discharged from the furnace top) is lower than the heat storage contained in coking coal and hot charcoal, the required compensation heat energy will be much lower than the energy consumption value of the sum of the heat storage of the corresponding coke oven and the coke added to the furnace.

[0017] 7) Maintaining the indirect reduction reaction of iron minerals. In order to compensate for the carbon monoxide originally produced by the carbon gasification reaction of bare coke (also known as Boudouard reaction, C+CO2=2CO) required for the indirect reduction of minerals in the closed carbonization process, biomass lumps, blue charcoal or small pieces of coal are directly added together with the product of the present invention and other furnace materials as carbon reactants to compensate for the carbon gasification reaction, and the addition ratio can be slightly larger than the addition ratio of coke powder or small coke when coke is used (because the closed product added as a transparent skeleton is less and it is also possible to expose the carbonized body to participate in the reaction in the furnace later).

[0018] 8) According to the current standards and existing evaluation indicators for shaft furnace coke, whether it is cold strength or thermal reactivity and other process carbonized body cold and hot strength and reactivity indicators, as long as the selection and proportion of carbon-rich materials can basically form a consolidated carbonized body under shaft furnace conditions, the products of the present invention can fully meet or do not need to be considered for evaluation.

[0019] 3. Beneficial effects

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] (1) The present invention provides a substitute product for metallurgical shaft furnace coke and its application method, which pre-packages carbon-rich substances and additives in a single micro carbon steel shell container with high strength, high durability and certain sealing properties as a carbonization chamber and directly adds the carbon-rich substances and additives into the furnace from the top along with the shaft furnace materials, thereby skipping the "coking" process and correspondingly eliminating a series of adverse effects caused by coking itself, such as energy consumption, carbon emissions and environmental pollution.

[0022] (2) The present invention provides a coke substitute product for metallurgical shaft furnaces and its application method. By pre-packaging carbon-rich substances and additives in a single micro carbon steel container with high strength, high durability and certain sealing properties as a carbonization chamber, the product is ensured to be fully sealed during the entire life cycle of processing and manufacturing, subsequent logistics and use in the shaft furnace, without leakage, loss, moisture absorption or peeling, which is conducive to clean production, reduced energy consumption and improved material utilization.

[0023] (3) The present invention provides a substitute product for metallurgical shaft furnace coke and its application method, which utilizes the shaft furnace pressure and the static pressure of the material column to enable the material enclosed in the heat-softened steel shell to be continuously squeezed at any time during the expansion, softening and contraction of the carbonization process (because it is always under pressure and the pressure is increasing during the semi-coke formation and final carbonization stages, its pressurized state is much better than that of hot-pressed coke), maintaining a high density, which is conducive to forming a compact final coke body, and also provides the possibility of expanding the use of biomass and recycled carbon-containing materials that cannot be reused, while also reducing the requirements for their processing precision.

[0024] (4) The present invention provides a substitute product for coke for metallurgical vertical furnaces and its application method. Due to the relatively high pressure in the vertical furnace, the volatilization temperature of the volatile matter in the carbon-rich material is increased and the volatilization amount is reduced, so that part of the active material is "degraded", part of the activated material is absorbed by the lean material, and part of the distilled gasified material is condensed on the surface of the upper cold material, so that the viscous material finally remaining in the material for coking increases accordingly, and the carbonized volume increases accordingly, which is beneficial to expand the types of available carbon-containing materials and improve the carbonization rate of carbon-rich materials.

[0025] (5) The substitute product for metallurgical shaft furnace coke of the present invention and its application method not only enable many types of coal that were previously unable to be used for coking due to their impact on coking production and coke cold properties to be added for use, thereby getting rid of the heavy reliance on coking coal required in the prior art, but also expands the types of carbon-rich materials that can be used in the shaft furnace.

[0026] (6) The present invention provides a substitute product for coke for metallurgical shaft furnaces and its application method. The product has a simple production process, a convenient production process, a high flexibility in material ratio, is easy to shape and compact, and can easily produce products of various specific shapes and uniform sizes. It is free of any undersize materials such as coke powder and coke fragments that cannot be used in shaft furnaces, and is free of coke fragments and ash produced by wear, reaction and deterioration in the furnace. On the premise of maintaining the air permeability of the system, the performance and size requirements for other materials entering the furnace are relatively relaxed.

[0027] (7) The present invention provides a substitute product for coke for metallurgical shaft furnaces and its application method, which is designed and used with a focus on the core function of the loose skeleton of coke. The carbon-rich material in the product is not degraded by reaction under the sealed protection of the outer shell and forms a high-strength, high-density carbonized body without broken particles. The loose skeleton function can be played more specifically, so that the proportion of the original carbon-rich material directly added, such as coal lumps and biomass lumps, which are mainly used as reducing agents, fuels, etc., can be relatively increased in the total amount of carbon entering the furnace.

[0028] (8) The present invention provides a substitute product for metallurgical shaft furnace coke and its application method, as a simple, convenient and clean way to directly consume part of the carbon-containing materials that are difficult to recycle (such as carbon-rich debris from urban garbage sorting) and biomass scraps that are difficult to properly dispose of (such as crop straw, fruit shells and animal feces residues), using a metallurgical shaft furnace. This can safely and reliably achieve the ideal effect of reducing fossil energy consumption and maintaining the environmental carbon dioxide cycle.

[0029] (9) Direct carbonization in the furnace produces relatively more carbon gasification products, which increases the calorific value of blast furnace gas to a certain extent.

[0030] (10) Existing coal yards and coal preparation and blending facilities for coke production can be fully utilized. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic diagram of a structural form of a coke substitute product for a metallurgical shaft furnace according to the present invention;

[0032] In the figure: 1. Alternative product for coke used in metallurgical shaft furnaces; 2. Miniature single-body steel closed container shell;

[0033] Figure 2 The longitudinal section diagram is a structural form of a substitute product for coke for a metallurgical shaft furnace according to the present invention.

[0034] In the figure: 1. Alternative product for coke used in metallurgical shaft furnaces; 2. Shell of a miniature single-body steel sealed container; 3. Mixed material containing carbon-rich substances inside. DETAILED DESCRIPTION

[0035] The invention discloses a coke substitute product for metallurgical shaft furnace, which is characterized by comprising a miniature single steel sealed container and a carbon-rich material mixed material densely filled therein for coking into carbon.

[0036] Furthermore, the shape of the miniature single steel container is any one of a straight surface, a curved surface, and a combination of straight and curved surfaces.

[0037] Furthermore, the maximum value of the relatively smallest thickness dimension of the three-dimensional equivalent length, width (height), and thickness of the miniature monomer sealed container is 20 to 60 mm.

[0038] Furthermore, the shell of the micro-monomeric steel sealed container is made of a carbon steel sheet, and the shell wall thickness is 0.06-0.40 mm. According to the specific weather resistance requirements, a coated plate or an oiled plate can be selected.

[0039] Furthermore, the maximum particle size of the solid carbon-rich material densely filled in the micro-monomer steel sealed container after crushing is no more than 4 mm.

[0040] Furthermore, the micro-monomeric sealed container is formed and sealed after being loaded with materials, and the degree of sealing is based on the principle of tightly sealing the powder and granular materials but not affecting the exchange of airflow.

[0041] Furthermore, the carbon-containing mixed material filled in the micro-monomer sealed container is pressurized and compacted to obtain a higher volume density, especially when a large proportion of crude processed biological carbon-rich materials, artificially synthesized carbon-rich materials and their recycled materials are used.

[0042] The present invention provides a method for using a coke substitute product for a metallurgical shaft furnace, characterized in that the carbon-rich material filled in the product is a mixture of one or more of fossil carbon-rich powder, biomass powder, and the processing byproducts of the two types of materials, and recycled powder or slurry. In order to reduce moisture and dust in the production process, it is beneficial to add a certain proportion of liquid carbon-rich material slurry, especially recycled slurry, but the final mixed material should not have fluidity (including vibration thixotropic flow).

[0043] Furthermore, it is characterized in that the manufacturing process of the product mainly includes: forming the outer shell container, filling the carbon-rich material into the container, pressurizing and compacting the carbon-rich material in the container, sealing the container and pre-shell or subsequent individualization of the filling body. The order of the above-mentioned manufacturing process can be adjusted according to the product manufacturing process and the equipment before and after. The order of the individualization process depends on the material filling method of the manufacturing process. When the material is filled independently, it is cut in advance, and when the continuous or simultaneous filling method is used, it is cut after filling.

[0044] Furthermore, its feature is that: during the charging process of the metallurgical vertical furnace, the above-mentioned product is added into the furnace from the top according to the calculated amount together with other furnace charges, and in the subsequent descending process, the heat energy of the rising high-temperature airflow itself is used to dry and distill the carbon-rich material in the micro-monomer closed container and realize its overall consolidation and carbonization.

[0045] Simultaneously, the additional fuel type and compensation amount corresponding to the heat required for the final carbonization of the components in the carbon-rich material replacing the coke in the furnace are determined according to the amount of product added and added into the furnace at the same time.

[0046] Furthermore, as the product moves downward with the charge, its outer shell and internal materials are gradually softened by the heat, and the furnace gas pressure and the static pressure of the upper materials will pressurize the product, gradually increasing its temperature and pressure, while the volume of its internal materials changes synchronously, continuously compacting the internal materials of the product in real time.

[0047] Furthermore, with the corrosion of furnace gas, the kneading of materials, the infiltration of carbon and the increase in temperature, the steel shell breaks, dissolves or melts, and the internal solidified carbonized body is exposed and then participates in metallurgical reactions, combustion reactions and carbonization of molten iron.

[0048] Furthermore, the unreacted and consumed carbonized blocks in the lower part of the vertical furnace will also support the upper material column in the lower part of the vertical furnace.

[0049] Furthermore, by designing the shape, size and wall thickness of the micro-monomer closed carbonization chamber, the retorting consolidation time required for product carbonization, the time to start the reaction in the furnace, the reaction specific surface area, and the air and liquid permeability can be obtained.

[0050] Furthermore, the reactivity and high temperature strength required by the product can be obtained through the design of the material formula inside the micro-monomer closed container.

[0051] Furthermore, by combining the size, wall thickness and internal material formula design of the micro-single closed container, the product can be designed to complete the metallurgical reaction and combustion reaction characteristics of the entire furnace process, as well as the high-temperature strength and target size of the remaining carbon required for subsequent support of the upper material column.

[0052] Furthermore, by designing the types and proportions of the carbon-rich substances, the proportion of coke produced in the final product, the proportion of volatile matter, the chemical composition of the volatile matter and the amount of harmful substances brought into the molten iron can be obtained.

[0053] Furthermore, external carbon material briquettes or small pieces of coal particles are directly added into the furnace along with other furnace charges, so that they can participate in the carbon gasification reaction as carbon before the shell of this product breaks, so as to compensate for part of the carbon monoxide required for indirect reduction in the furnace.

[0054] Furthermore, in order to optimize the use effect, products with different micro-single container sizes, shell thicknesses and different internal material formulas can be used in combination at the same time.

[0055] Furthermore, according to the extended furnace reaction and material distribution of a specific vertical furnace, different radial distributions of the cross section can be achieved by adding different characteristic products and directly added carbon materials to optimize the metallurgical reaction and the functional realization of the carbon materials.

[0056] The present invention is further described below in conjunction with specific embodiments.

[0057] Example 1

[0058] The present embodiment is a substitute product for coke used in a metallurgical shaft furnace, comprising a micro-mono-enclosed container and a carbon-rich material filled in its inner cavity. The micro-mono-container is a round box with a carbon steel shell and a lid, with a diameter of 70 mm and a height of 40 mm, and a round box shell thickness of 0.14 mm; the material is a mixture of 10% fat coal, 70% lean coal, 15% sawdust, and 5% crushed urban recycled plastic, the maximum particle size after crushing is no more than 4 mm, and the total moisture content of the material is 5.8%; the material is compacted after being added to the round box and the lid is locked.

[0059] Example 2

[0060] The present embodiment provides a coke substitute product for a metallurgical shaft furnace, comprising a micro-mono-enclosed container and a carbon-rich material filled in its inner cavity. The micro-mono-container is a two-piece carbon steel shell with a lid and a diameter of 60 mm and a height of 30 mm. The thickness of the shell of the round box is 0.06 mm, and the thickness of the lid is 0.10 mm. The material is a mixture of 15% fat coal, 80% lean coal, and 5% crushed urban recycled plastic, and the maximum particle size after crushing is no more than 3.5 mm. After the material is added, pressurize and lock the lid.

[0061] Example 3

[0062] like Figure 1 and Figure 2 As shown, a metallurgical coke substitute product for a casting cupola furnace in this embodiment includes a miniature monomer sealed container and a carbon-rich material filled in its inner cavity. The container has a thickness of 60 mm, a carbon steel shell thickness of 0.4 mm, a container width and a length of 75 mm and 120 mm, respectively. The material is 20% fat coal, 70% lean coal, and 10% filter press dehydrated and minced food waste collection. The maximum particle size after crushing is no more than 4 mm. After the material is added, it is pressurized and sealed at the edge and head.

[0063] Example 4

[0064] This embodiment is a substitute product for coke used in metallurgical shaft furnaces, and is a processed product continuously produced by a group stamping and stretching device. The specific thickness of the steel strip used is 0.30mm, and the container shell is formed by one-step extrusion and multi-step stretching; the carbon-rich material densely filled inside for coking and charring is anthracite, with a small amount of bituminous coal and sawdust (particle size not greater than 5mm), and a small amount of recycled food waste slurry is also added to reduce dust; the shape of the shaped product is an elliptical barrel body composed of straight and curved surfaces, with a three-dimensional equivalent thickness of 40mm and a length of 80mm, and a shell wall thickness of 0.08-0.15mm for iron-making blast furnaces.

[0065] Example 5

[0066] like Figure 1 and Figure 2 As shown, a substitute product for metallurgical coke used in an ironmaking blast furnace in this embodiment includes a micro-monomer sealed container and a carbon-rich material filled in its inner cavity. The container is 40 mm thick, the carbon steel shell is 0.20 mm thick, and the container is 55 mm wide and 70 mm long respectively; the material is a mixture of 20% fat coal, 70% lean coal, 10% sawdust and 3% recycled food waste floating oil scraps, the maximum particle size after crushing is no more than 4 mm, and the material is pressurized and sealed at the edges and ends after being added.

[0067] Example 6

[0068] The present embodiment is a substitute product for coke for a metallurgical vertical furnace and its dry distillation, including a miniature monomer sealed container, a carbon-rich substance filled in its inner cavity, and product production and dry distillation process operations and related parameters. The miniature monomer container is a round box with a carbon steel shell and a lid with a diameter of 60mm and a height of 40mm, and the thickness of the round box shell is 0.14mm; the material is a mixture of 20% fat coal, 60% lean coal, 15% sawdust and 5% crushed urban recycled plastics, and the maximum particle size after crushing is no more than 3.5mm, the fineness is 86%, and the total moisture content of the material is 5.8%; the product production and dry distillation process operations and related parameters are: 1) After the material is added to the round box and the lid is locked, it is heated at 3kg / cm 3 The material was compacted by pressure and weighed to obtain a bulk density of 1.02 g / cm 3 ; 2) Place the round box with the sealed and locked lid into a heating furnace and heat it to 1000°C at an average rate of 9°C / min; 3) Keep it at 1000°C for 15 minutes and take it out to cool at room temperature; 4) The carbonized body is solid and complete, and the apparent density of the carbonized body is 0.721g / cm 3 .

[0069] Example 7

[0070] The present embodiment is a substitute product for coke for a metallurgical shaft furnace and its dry distillation, including a miniature monomer sealed container, a carbon-rich substance filled in its inner cavity, and product production and dry distillation process operations and related parameters. The miniature monomer container is a round box with a carbon steel shell and a lid with a diameter of 60mm and a height of 40mm, and the thickness of the round box shell is 0.14mm; the material is a mixture of 20% fat coal, 60% lean coal, 15% sawdust and 5% crushed urban recycled plastics, and the maximum particle size after crushing is no more than 3.5mm, the fineness is 86%, and the total moisture content of the material is 5.8%; the product production and dry distillation process operations and related parameters are: 1) After the material is added to the round box, it is heated at 3kg / cm 3 The bulk density of the material was calculated to be 1.02 g / cm 3 ; 2) A round steel block with a diameter of 55mm and a thickness of 20mm is used to press the material in the round box; 3) A steel block weighing 20kg (preheated to 600℃) is placed flat on the steel block and put into the heating furnace together; 4) The temperature is raised to 1000℃ at an average rate of 9℃ / min; 5) The round box is taken out and cooled at room temperature after keeping at 1000℃ for 15 minutes; 6) The carbonized body is solid and complete, and the height is reduced by 21%. The apparent density of the carbonized body is measured to be 0.913g / cm 3 .

[0071] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical content disclosed by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and so on quoted in this specification are only for the convenience of description, and are not used to limit the scope of implementation. The change or adjustment of their relative relationship should also be regarded as the scope of implementation of the present invention without substantially changing the technical content.

Claims

1. A coke substitute product for metallurgical shaft furnace, characterized in that: The invention comprises a miniature single steel sealed container as a carbonization chamber and a carbon-rich material mixed material densely filled therein for coking into carbon in a vertical furnace.

2. The coke substitute product for metallurgical shaft furnace according to claim 1, characterized in that: The miniature single steel container has an outer shape of any one of a straight surface, a curved surface, and a combination of straight and curved surfaces, and the maximum value of the relatively smallest thickness dimension in the three dimensions of the outer shape equivalent length, width, and thickness is 20 to 60 mm.

3. The coke substitute product for metallurgical shaft furnace according to claim 1, characterized in that: The shell material of the miniature single steel sealed container is a carbon steel thin plate, and the shell wall thickness is 0.06-0.40 mm.

4. The coke substitute product for metallurgical shaft furnace according to claim 1, characterized in that: The maximum particle size of the carbon-rich material densely filled in the micro-monomer steel sealed container after being crushed is no more than 4 mm.

5. The coke substitute product for metallurgical shaft furnace according to claim 1, characterized in that: The sealing degree of the miniature single-body steel sealed container does not affect the exchange of internal and external airflows.

6. A method for using a substitute product for coke in a metallurgical shaft furnace, characterized in that: 1) The carbon-rich material filled in the product described in any one of claims 1 to 5 is a mixture of one or more of fossil carbon-rich powder, biomass powder, and the processing byproducts of these two types of materials, recycled powder or slurry; 2) The main processing and manufacturing process of the product according to any one of claims 1 to 5 is: forming the outer shell into a container shape, filling the container with carbon-rich material, pressurizing and compacting the carbon-rich material in the container, and sealing the container; 3) When in use, the product according to any one of claims 1 to 5 is added to a metallurgical vertical furnace along with other furnace materials and gradually descends and is heated continuously. (1) The product's miniature single steel sealed container serves as an independent self-consumable carbonization chamber and utilizes the sensible heat energy of the high-temperature furnace gas in the furnace to carry out closed drying, carbonization and carbonization of the internal carbon-rich materials. (2) The furnace gas pressure and the static pressure of the upper materials continuously pressurize and compact the carbon-rich materials in the product whose outer shell is heated and softened in real time. (3) The steel outer shell of the product gradually ruptures, carburizes, dissolves or melts, exposing the internal carbonized body, which continuously expands and then participates in metallurgical reactions, combustion reactions and carbonization of molten iron. (4) During the whole process, the product collection and the mixture with other vertical furnace materials maintain good gas-liquid permeability. (5) The remaining carbonized body supports the material column at the lower part of the vertical furnace.

7. The method for using a coke substitute product for a metallurgical shaft furnace according to claim 6, characterized in that: By designing the structure, size, wall thickness, shape and compacted density of the internal materials in the micro-monomer sealed container of the product and combining it with the internal material formula design, it is possible to obtain the time required for full carbonization of the product, the time when the carbonized body begins to participate in the reaction in the furnace, the density of the carbonized body, the reaction specific surface area and the gas-liquid permeability, as well as the high-temperature strength required to support the upper material column while completing the process reaction and the target size of the process coking carbonized blocks.

8. The method for using a coke substitute product for a metallurgical shaft furnace according to claim 6, characterized in that: By designing the types and proportions of carbon-rich substances in the product, the proportion of coke bodies, the proportion of volatiles, the chemical composition of the volatiles, the ash content and the amount of harmful substances brought into the molten iron can be obtained.

9. The method for using a coke substitute product for a metallurgical shaft furnace according to claims 6-8, characterized in that: The carbon-rich material lumps are directly added along with the products and other furnace materials to compensate for the carbon reactants required for the carbon gasification reaction for indirect reduction of minerals in the furnace.

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