A method for increasing production and reducing consumption in blast furnace smelting

Abstract

This application discloses a method for increasing blast furnace production and reducing consumption, comprising the following steps: using a closed-end rectifying distribution chute for a series-tank blast furnace, and a closed-end rectifying distribution chute and / or a rectifying center throat pipe for a parallel-tank blast furnace; distributing the distribution using an existing charging system and distribution matrix, and smelting for one to two cycles; determining the specific type of distribution within the furnace based on the furnace conditions and the throat gas flow distribution curve; the type being selected as edge-developed, bimodal, center-developed, or flat; and adjusting the distribution to a more optimal type or approaching the next more optimal type. This method, based on uniform and precise distribution, establishes an optimized edge gas flow and a stable center gas flow distribution, thereby improving gas utilization and increasing blast furnace production efficiency, resulting in significant economic benefits.

Description

Technical Field

[0001] The present application relates to the technical field of blast furnace charge distribution technology, and in particular to a method for increasing production and reducing consumption in blast furnace smelting. Background Art

[0002] The bell-less furnace top charging equipment system consists of a receiving hopper, two charging tanks (including upper and lower sealing valves, throttle valves, fork pipes), a distributor (including a central throat pipe), and a chute. The charge is loaded into the charging tank from the receiving hopper, and flows out of the charging tank along the central throat pipe into the rotating chute, falling onto the charge surface in the furnace while rotating. Figure 1 As shown in the figure, each batch of material is usually laid out with 8 to 15 turns (depending on the size of the furnace). The chute angle can be easily changed and controlled, making the material laying very flexible.

[0003] The operation of the blast furnace is affected by the raw materials and fuel conditions. Different distribution matrix controls and upper and lower adjustments are adopted to make the throat gas flow distribution curve of the blast furnace form edge development type, double peak type, center development type and flat type.

[0004] The edge-development type is primarily designed for ironmaking with poor raw materials. It requires very high air permeability and stability. To maximize airflow, the airflow is directed toward the edges. Edge-development gas can severely corrode the furnace walls, leading to high temperatures near the walls and rapid corrosion of the furnace lining, shortening the life of the blast furnace. This increased furnace temperature increases heat loss, hindering the full utilization of the thermal and chemical energy in the gas. This increases the top gas temperature and fuel consumption.

[0005] The characteristics of the bimodal type are: it is mainly used for ironmaking with raw materials that are relatively common. It requires good air permeability and high stability. To achieve high airflow, the airflow is greatly developed towards the edges and center. It also causes severe erosion of the furnace wall, high top gas temperature, and average gas energy utilization.

[0006] The central development type is primarily designed for ironmaking with relatively high-quality raw materials. It requires high permeability and stability. To achieve a high airflow path, the airflow is primarily directed toward the center. This reduces gas erosion of the furnace walls, extending the life of the furnace lining. The gas flows through the center of the blast furnace, fully contacting the charge, fully utilizing both its physical heat and chemical energy, thereby reducing fuel consumption. Maintaining a strong and narrow central gas flow peak is the most economical gas distribution for blast furnaces.

[0007] The flat type is primarily designed for ironmaking with high-quality raw materials. It requires relatively low permeability, stability, and airflow channels, as well as low requirements for both edge and center airflow. It has minimal erosion of the furnace walls, lower top gas temperatures, and better gas energy utilization. However, it has higher requirements for charge material and poor resistance to furnace interference.

[0008] Currently, large blast furnaces typically utilize a centrally developed and flatly distributed gas distribution system at the throat. While maintaining smooth operation, this type of distribution is achieved, moving closer to a flatter distribution. Typically, blast furnaces with moderate fine material levels employ a centrally developed distribution system that strengthens the central gas flow to stabilize furnace conditions and mitigate the impact of external fluctuations on smooth operation. Blast furnaces with high fine material levels employ a flatter distribution system to optimize utilization of the gas's chemical and thermal energy.

[0009] However, for the existing serial tank bell-less charging, the charge falls along the central throat, and the charge flow through the chute outlet is scattered, which makes the charge falling on the charge surface in the furnace uneven in the radial direction of each ring; because the width of the charging ring is too large, the overlap between each ring and the adjacent ring is too large, and the rolling and scattering of coke and ore are different, the circumferential radial ore-coke ratio is unstable and has a large difference, resulting in uneven gas flow distribution in the radial direction of each ring of the blast furnace, affecting the improvement of gas utilization and the improvement of production efficiency; and for the parallel tank bell-less charging, While there is the same radial unevenness of each ring in the string-type distribution, since the two tanks are symmetrically inclined to drop the materials to the central throat, eccentricity occurs. After falling into the rotating chute, the distribution direction is an eccentric and irregular circle, and the distribution amount is not uniform on the circumference, resulting in eccentricity in the thickness of the distribution layer and instability of the ore-coke ratio in the circumferential direction. In addition, the eccentric and uneven distribution of the coal gas flow will cause the center coal gas flow to shift, the edge coal gas flow to be uneven in strength, and the edge and center coal gas flow distribution to be unreasonable, further affecting the improvement of coal gas utilization and the improvement of production efficiency.

[0010] Therefore, in response to the above technical problems, the first thing to do is to achieve uniform and accurate distribution of materials. Then, on the premise of uniform and accurate distribution of materials, appropriate edge airflow and stable central airflow distribution should be established to improve gas utilization and increase blast furnace production efficiency. These are technical problems that technicians need to solve. Summary of the Invention

[0011] The purpose of this application is to provide a method for increasing production and reducing consumption in blast furnace smelting, which uses a chute and / or a central throat to rectify the furnace charge. The series-type bell-less blast furnace adopts a closed-end rectifying distribution chute, and the parallel-type bell-less blast furnace adopts a closed-end rectifying distribution chute and / or a rectifying central throat; the thickness and ore-coke ratio of the distribution ring material table in the radial direction are made more uniform, and the parallel-type cans make the eccentric circle of the material flow landing point more round. On this basis, the specific type of distribution in the furnace is determined according to the gas flow distribution in the furnace throat, thereby establishing a suitable edge gas flow and a stable central gas flow distribution, improving gas utilization and increasing blast furnace production efficiency. The closed-end rectifying distribution chute used in this case is at 4000m 3The on-site distribution width test was carried out on the blast furnace with the arc-shaped outlet chute. When the chute was at a 42° angle, the distribution platform width of the ore in the closing and rectifying chute was 360mm, and the distribution platform width of the coke was 700mm. For the existing arc-shaped outlet chute, the distribution platform width of the ore was 800mm, and that of the coke was 1300mm.

[0012] To achieve the above objectives, the present application provides a method for increasing blast furnace smelting production and reducing consumption, comprising the following steps:

[0013] Step a: The serial-tank bell-less blast furnace adopts a closed-end rectifying distribution chute, and the parallel-tank bell-less blast furnace adopts a closed-end rectifying distribution chute and / or a rectifying center throat;

[0014] Step b: Charge the blast furnace according to the original charging system and charging matrix, and observe the changes in the furnace condition after smelting for 1-2 cycles;

[0015] Step c, determining the specific type of distribution in the furnace based on the raw materials, fuel conditions, furnace conditions of blast furnace smelting and the furnace throat gas flow distribution curve;

[0016] Step d, the type is one of the following: edge development type, bimodal type, central development type or flat type;

[0017] Wherein, when the type is edge development type, it is adjusted to optimized edge development type or close to bimodal type;

[0018] When the type is a bimodal type, adjust to an optimized bimodal type or a type close to the central development type;

[0019] When the type is a central development type, adjust it to an optimized central development type or a near-flat type;

[0020] When the type is a flat type, it is adjusted to a more optimal flat type with a wider coke platform.

[0021] Preferably, during the type adjustment process, the ore-coke ratio is increased by 2-10%, thereby reducing the coke consumption per ton of molten iron.

[0022] Preferably, during the type adjustment process, the coal powder consumption is reduced by 3-15 kg / t of molten iron.

[0023] Preferably, when the type is edge development type, the number of center coke distribution rings is increased, while the number of edge coke distribution rings is reduced and / or the number of edge ore distribution rings is increased.

[0024] Preferably, the number of center coke distribution rings is increased by 10-20% of the number of coke distribution rings, the number of edge coke distribution rings is reduced, and the number of edge ore distribution rings is increased.

[0025] Preferably, when the type is bimodal, the comprehensive angular position difference of ore and coke in the distribution matrix is ​​gradually adjusted to increase by 0.3-0.5° in batches, the excessive development of edge airflow is reduced, the number of ore distribution rings is increased, and the width of the ore and coke platform formed on the material surface in the furnace is increased.

[0026] Preferably, while reducing the excessive development of the edge airflow, the number of center focusing rings and the amount of focus are increased or decreased according to the changes in the edge airflow to obtain a suitable center airflow.

[0027] Preferably, the throat gas center temperature and the throat gas edge temperature are appropriately reduced to 50-300° C., and the width of the coke platform is increased by 5-20%.

[0028] Preferably, when the type is the central development type, first loosen the edge gas flow, reduce the number of central coke distribution rings by more than 20%, increase the width of the coke platform by 5-20%, and then reduce the edge gas flow according to the changes.

[0029] Preferably, the temperature of the center point of the furnace throat gas is appropriately reduced by 100-300°C, and the temperature of the edge point of the furnace throat gas changes by 50-150°C.

[0030] Preferably, when the type is a flat type, the width of the coke platform is increased by 3-10%, and the edge coal gas flow or the center coal gas flow is reduced.

[0031] Preferably, according to the adjusted furnace conditions, the proportion of pulverized coal in fuel consumption is increased and the proportion of coke is reduced.

[0032] Compared to the above background technology, this application adopts a closed-end rectifying distribution chute for the serial-tank bell-less blast furnace; and a closed-end rectifying distribution chute or an additional rectifying center throat for the parallel-tank bell-less blast furnace, so that the eccentricity of the material flow falling into the chute is reduced, the two-way direction correction effect is better, and the regular material flow achieves more uniform and accurate distribution. On this basis, the original charging system and distribution matrix of the blast furnace are first used for distribution, and after 1-2 cycles of smelting, the ore-coke ratio in the blast furnace charge layer is made more uniform. In addition, the deviation of the peripheral and central airflow of the parallel-tank is reduced, and the changes in the furnace condition after the regular material flow distribution are observed.

[0033] The specific type of gas flow distribution within the furnace is determined based on raw material and fuel conditions, observation of furnace conditions after regular material flow distribution, and the throat gas flow distribution curve. The type is selected from edge development, bimodal, center development, or flat. If the type is edge development, the optimization is adjusted to an optimized edge development or close to a bimodal type; if the type is bimodal, the optimization is adjusted to an optimized bimodal type or close to a center development type; if the type is center development, the optimization is adjusted to an optimized center development or close to a flat type; if the type is flat, the optimization is adjusted to a more optimal flat type with a wider coke platform. This establishes appropriate edge gas flow and stable center gas flow distribution, improving gas utilization and increasing blast furnace production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0035] Figure 1 This is a schematic diagram of the chute's distribution point structure in the furnace;

[0036] Figure 2 A schematic diagram of a furnace throat gas flow distribution curve provided in an embodiment of the present application;

[0037] Figure 3 A flow chart of the method provided in the embodiment of the present application;

[0038] Figure 4 This is a schematic diagram of the structure of material flow deviation and uneven material distribution in the prior art;

[0039] Figure 5 A schematic diagram comparing the material flow distribution trajectory in the prior art and the material flow distribution trajectory in this application;

[0040] Figure 6 A schematic diagram of the structure of the rectifier center throat provided in an embodiment of the present application;

[0041] Figure 7 for Figure 6 Schematic diagram of the structure in the A direction.

[0042] In the figure: 1- material tank, 2- central throat, 3- chute, 4- furnace charge, 5- deviated distribution track, 6- distribution track after rectification, 7- material guide pipe body, 8- central diversion hole, 9- inlet funnel, 10- diversion device. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0044] It should be noted that in this embodiment, the directions or positional relationships indicated by "upper," "lower," "front," and "back" are based on the directions or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this application and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific direction, be constructed, or operate in a specific direction. Therefore, they should not be construed as limitations on this application. Furthermore, "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0045] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0046] In this embodiment, a method for increasing production and reducing consumption in blast furnace smelting is provided. For the operation of each blast furnace, the furnace master will comprehensively consider the production, fuel ratio, and forward flow according to the conditions of the corresponding blast furnace itself, the charge, and the stability, and adopt different distribution matrix controls and upper and lower adjustments to make the blast furnace throat gas flow distribution curve form edge development type, double peak type, center development type, and flat type. Specifically, Figure 2 shown.

[0047] like Figure 4 As shown, for the blast furnace with connected tanks, since the outlet material flow of the chute 3 is scattered and thrown out, it diverges unevenly in the radial direction, the material ring is too wide, and there is too much overlap between the rings, which causes the thickness of the ore and coke to be different in the radial direction; and because of the eccentricity of the material discharge of the central throat pipe 2 in the parallel tank, the distribution circle is eccentric, and the distribution thickness deviates in the circumferential direction, which further increases the deviation of the ore-coke ratio in the circumferential direction.

[0048] For the serial tank bell-less blast furnace, this application adopts a closing-end rectifying distribution chute, and the parallel tank bell-less blast furnace adopts a closing-end rectifying distribution chute or adds a rectifying center throat. The rectification of the closing-end rectifying distribution chute has a certain inhibitory and regularizing effect on the eccentricity of the center throat. Adding a rectifying center throat can reduce the eccentricity of the charge 4 falling into the closing-end rectifying distribution chute. For details, please refer to Figure 5 , Figure 5 The figure below compares the deflected charge distribution trajectory 5 with the rectified charge distribution trajectory 6. Bidirectional directional correction provides enhanced performance, and the regulated charge distribution 4 achieves more uniform and precise distribution, resulting in more consistent radial thickness of the charge ring and a more consistent ore-coke ratio. Furthermore, the circumferential eccentricity of the charge distribution in a parallel-tank blast furnace is reduced, thereby minimizing circumferential thickness deviations and ore-coke ratio deviations caused by charge ring eccentricity, thereby ensuring more stable blast furnace operation.

[0049] It should be noted that the closing-end rectifying distribution chute can refer to the Chinese patent with application number CN202222163128.2. During the blast furnace distribution process, the material in the chute body can first flow through the rectification part, and then flow out through the flat discharge port to the blast furnace material surface. The rectified material flow flows out from the flat discharge port, which can make the material layer thickness leaving the discharge port of the closing-end rectifying distribution chute as thin as possible without blocking the material, and effectively avoid the divergence and turbulence of the material flow, effectively reduce the area of ​​the scattered material flow, and make the width of the material surface ring (material platform) where the rotating distribution parabola falls to the material surface in the blast furnace as narrow as possible, thereby achieving precise distribution.

[0050] like Figure 6 As shown, the rectifying central throat includes a guide pipe body 7 with a central guide hole 8. The guide pipe body 7 serves as the main feeding channel for the furnace charge 4. The furnace charge 4 is discharged into the central guide hole 8 through the material tank 1, and then rectified by the central guide hole 8 and discharged into the closing rectifying distribution chute for distribution.

[0051] An inlet funnel 9 is provided at the upper end of the guide tube body 7. The inlet funnel 9 is a truncated cone structure and is used to increase the feeding area of ​​the central guide hole 8 to facilitate the discharge of the furnace charge 4. The lower end of the inlet funnel 9 is connected to the upper end of the guide tube body 7. At the same time, a diverter device 10 is provided at the connection between the inlet funnel 9 and the guide tube body 7. The diverter device 10 can play a certain buffering role to prevent the furnace charge 4 from flowing eccentrically in the opposite direction. Specifically, in the process of charging the parallel-tank bell-less blast furnace, since the two material tanks 1 are respectively located on both sides of the guide tube body 7, the discharge port usually has a certain inclination when discharging the material, specifically as shown in FIG. Figure 1 As shown, in this case, if the diversion device 10 is not provided, the charge 4 will move toward the side wall on the other side of the central guide hole 8 under the action of gravity and the inclined discharge port, and will not be able to move downward along the side wall by relying on its own gravity until it reaches the side wall on the other side. This will cause the charge 4 to be mostly located at the side wall and cannot be evenly distributed in the central guide hole 8.

[0052] However, the setting of the diverter device 10 can, on the one hand, buffer the initial speed of the charge 4 and prevent the wear of the side wall of the central guide hole due to long-term erosion of the charge 4; on the other hand, it can also evenly distribute the charge 4 to avoid the situation where all of the charge 4 flows eccentrically in the opposite direction.

[0053] In addition, the upper end of the above-mentioned central guide hole 8 has a circular opening, which is convenient for the entry of the charge 4 and can also play the role of circumferential distribution of the charge 4. The central guide hole 8 has a slope facing its interior from top to bottom; that is, the interior of the central guide hole 8 is arranged in a manner that is wide at the top and narrow at the bottom, that is, after the charge 4 enters the central guide hole 8, under the action of the slope, the charge 4 can make a certain tilting movement along the slope, so that when it moves by its own gravity, it has an initial velocity in the horizontal direction. When the charge 4 leaves the central guide hole 8, it can continue to flow to the central axis of the guide tube body 7 by relying on the horizontal velocity, and can further correct and rectify the eccentric material flow.

[0054] It should be noted that, for the above-mentioned raised slope, at any longitudinal section of the slope, it gradually approaches the central axis of the guide tube body 7 from top to bottom, and the cross-sectional line of the slope is a smooth inclined line. Figure 6 .

[0055] Figure 7 for Figure 6 In the diagram of the structure in the middle A direction, the guide tube body 7 has a circular upper opening and an elliptical lower opening, resulting in a central flow guide hole 8 having a slope from top to bottom that rises toward its interior. Alternatively, a structure with circular openings at both top and bottom, where the upper circular opening has a larger diameter than the lower circular opening, could also be used to create a slope that rises toward its interior. The specific configuration of the slope will not be detailed here.

[0056] After rectification through the closing rectifier-type distribution chute and the rectifying center throat, the blast furnace is first distributed according to the original charging system and distribution matrix, as shown in Table 1. This is one of the existing distribution matrices. Taking this matrix as an example for distribution, after 1-2 smelting cycles, the ore-coke ratio in the blast furnace charge layer is made more uniform, and the deviation of the peripheral and central airflow of the tank is reduced. The changes in the furnace condition after the regular material flow distribution are observed.

[0057] Table 1: Existing fabric matrix

[0058] Chute angle (°) 35.5 34.5 33 32 30 29 27 Ore distribution circle number 2 3 2 3 2 3 2 Chute angle (°) 35.5 34 32 30 27.5 23 13 Number of coke distribution circles 3 3 3 2 2 1 3

[0059] Due to the precise distribution, the deviation of the material layer thickness and the ore-coke ratio are reduced, and the stability of the furnace condition is enhanced accordingly. In addition, the eccentricity of the tank in the distribution circle is reduced, and the deviation of the peripheral and central airflow is reduced, and the stability of the furnace condition will be further enhanced. The enhancement of the stability of the furnace condition provides a lot of space for the subsequent adjustment of the furnace condition and the adoption of measures to increase production and save coke.

[0060] Then according to the raw materials, fuel conditions, blast furnace conditions and throat gas flow distribution curve, such as Figure 2As shown, the original charging system and distribution matrix parameters of the blast furnace were optimized, such as increasing or decreasing the single feed rate, increasing the number of segmented distribution rings, splitting the number of distribution rings at the same angle, adjusting the spacing between distribution rings, and adjusting the comprehensive angular position difference of the ore and coke. This achieved a more uniform radial distribution of the material flow on the charge surface, as well as a more uniform distribution of the actual circumference and flow rate. This achieved a stable ore and coke load for each batch and a uniform and reasonable distribution of the coal gas flow in the circumferential direction.

[0061] Specifically, according to Figure 2 The specific type of distribution in the furnace is determined by the throat gas flow distribution curve; the type is one of the four types: edge development type, bimodal type, center development type or flat type.

[0062] This application is adjusted on the basis of greatly improving the stability and reducing the safety factor, until the stability reaches an acceptable state that is slightly weaker than the original stability, so as to maximize the improvement of production efficiency and the reduction of coke ratio. Figure 3 As shown in the figure, the specific adjustment methods for different types are:

[0063] Among them, when the type is edge development type, the edge development type or close to the bimodal type is optimized;

[0064] When the type is bimodal, optimize the bimodal type or the near-central development type;

[0065] When the type is central development type, optimize the central development type or close to the flat type;

[0066] When the type is flat type, adjust it to a better flat type with a wider coke platform.

[0067] That is to say, in order to ensure the air permeability of more ore and less coke, the existing technology is forced to reduce the proportion of ore, while the fabric of this application reduces the unevenness of ore and coke. By appropriately increasing a certain proportion of ore, the original air permeability effect can be achieved. If a certain amount is added, the air permeability is stronger than the original one. The improvement of air permeability creates conditions for reducing the peripheral and central airflow.

[0068] During the above four types of adjustment, the ore-coke ratio (O / C) is appropriately increased by 2-10%, the coke consumption per ton of molten iron is reduced, and the coal powder consumption is reduced by 3-15 kg / t of molten iron to achieve the purpose of reducing the fuel ratio.

[0069] Improved stability creates the conditions for expanding the charge surface platform. A reasonable charge surface platform width or area is crucial to blast furnace production efficiency. If the charge surface platform is too narrow, the central hopper will be too wide and deep, and the central gas flow will be overdeveloped. If the charge surface platform is too wide, the central hopper will become narrower and shallower, and the furnace stability will deteriorate.

[0070] In general, the technical approach of this application is to reduce the uneven deviation of blast furnace charge distribution by using a closed-end rectifier-type distribution chute or adding a rectifier-type central throat to the combined blast furnace. In this way, the permeability of the ore platform is improved, the gas utilization rate is increased, and the operational stability is improved; the surplus operational performance supports the adjustment and expansion of the ore and coke platform, and the stability is changed to an acceptable state. At the same time, the edge and center airflows are adjusted to each other, and the overall airflow is reduced, thereby reducing the coke ratio. For four typical blast furnace smelting types, the specific adjustments are as follows:

[0071] When the type is edge development type, appropriately increase the number of center coke distribution rings, and appropriately reduce the number of edge coke distribution rings and / or increase the number of edge ore distribution rings. That is, the actual edge over-strong airflow is reduced, and the center airflow is appropriately increased, and the overall airflow is appropriately reduced. Appropriately increasing the number of center coke distribution rings is preferably 10-20% of the number of coke distribution rings, and appropriately increasing and reducing the number of edge coke distribution rings and increasing the number of edge ore distribution rings accordingly. In this way, the ultra-high edge airflow is reduced to a high edge airflow, the center airflow is increased to form a double peak, and the ore coke platform area is increased, which can improve production efficiency, increase output, reduce the overall airflow, and reduce the coke ratio;

[0072] For a bimodal furnace, the angular position difference between the ore and coke in the distribution matrix is ​​gradually increased by 0.3-0.5°. This increases the ore at the edges, reducing the amount of coke added, and thus reducing the overdevelopment of the edge airflow. The number of ore distribution rings is then appropriately increased, widening the coke platform formed on the furnace surface by 5-20%. While reducing the overdevelopment of the peripheral airflow, the number of center coke feeding rings and the amount of coke added are then appropriately increased or decreased based on these changes to achieve an appropriate center airflow. The adjusted edge and center airflows exhibit high center airflow and relatively low edge airflow, thus optimizing the bimodal or near-center development model. The overall airflow is lower than the original flow rate, improving gas utilization and reducing the fuel ratio. The center and edge throat gas temperatures are appropriately reduced to 50-300°C, increasing the width of the coke platform by 5-20%.

[0073] For the central development type, initially, the edge gas flow is appropriately loosened, while the number (volume) of central coke distribution rings is reduced by more than 20%, and the width of the coke platform is increased by approximately 5-20%. Based on these changes, the edge gas flow is then appropriately adjusted back to reduce the flow. This adjustment significantly reduces the central gas flow, adjusting it to the more optimal central development type, with a strong and narrow central gas flow peak, or a near-flat type. This improves gas utilization, reduces the fuel ratio, and increases production. The central throat gas temperature will decrease by 100-300°C, while the throat gas edge temperature will change by 50-150°C.

[0074] When the type is flat, increase the width of the coke platform by about 3-10%, appropriately reduce the edge gas flow or center gas flow, and adjust it to a better flat type to achieve the purpose of improving gas utilization, reducing fuel ratio, and increasing production.

[0075] The fuel consumption is composed of the coke used for distribution and the pulverized coal injected in the tuyere. In this application, the proportion of pulverized coal in the fuel consumption can be increased according to the adjusted furnace conditions to replace the coke and reduce the cost.

[0076] Research and test evaluation show that the use of the technical solution of the present invention can increase the average output by 5-15%, reduce the coke consumption by 5-15kg / t molten iron, and reduce the coal powder by 5-10kg / t molten iron. 3 Actual blast furnace tests have shown an 8% increase in average daily output from 8,500 tons to 9,200 tons. Fuel consumption has been reduced from 550 kg / t of hot metal (coke at 390 kg / t and coal at 160 kg / t) to 525 kg / t (coke at 375 kg / t and coal at 150 kg / t). This represents a decrease in coke consumption of 15 kg / t and pulverized coal consumption of 10 kg / t. Currently, China's annual hot metal production exceeds 1 billion tons. If this solution is adopted for existing 400 million tons of production capacity, assuming a 6% output increase, the annual increase in hot metal production could reach 24 million tons, approaching the annual output of Ansteel Co., Ltd. With a reduction in coke consumption of 8 kg / t and pulverized coal consumption of 6 kg / t, the annual fuel savings would amount to 4*8*2.5 + 4*6*1.2 = 10.88 billion yuan, representing significant economic benefits.

[0077] It should be noted that, in this specification, relational terms such as first and second are merely used to distinguish one entity from other entities, but do not necessarily require or imply any actual relationship or order between these entities.

[0078] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above examples is only intended to help understand the method and core ideas of this application. It should be noted that for those skilled in the art, without departing from the principles of this application, various improvements and modifications can be made to this application, and such improvements and modifications also fall within the scope of protection of the claims of this application.

Claims

1. A method for increasing production and reducing consumption in blast furnace smelting, characterized in that: The following steps are involved: Step a: The serial-tank bell-less blast furnace adopts a closed-end rectifying distribution chute, and the parallel-tank bell-less blast furnace adopts a closed-end rectifying distribution chute and / or a rectifying center throat; Step b: Charge the blast furnace according to the original charging system and charging matrix, and observe the changes in the furnace condition after smelting for 1-2 cycles; Step c, determining the specific type of distribution in the furnace based on the raw materials, fuel conditions, furnace conditions of blast furnace smelting and the furnace throat gas flow distribution curve; Step d, the type is one of the following: edge development type, bimodal type, central development type or flat type; Wherein, when the type is edge development type, the number of center coke distribution rings is increased, while the number of edge coke distribution rings is reduced and / or the number of edge ore distribution rings is increased, and the increase in the number of center coke distribution rings is 5-20% of the number of coke distribution rings, so as to adjust to the optimized edge development type or close to the bimodal type; When the type is bimodal, gradually increase the comprehensive angular position difference of ore and coke in the distribution matrix by 0.3-0.5°, reduce the excessive development of edge airflow, increase the number of ore distribution rings, and increase the width of the ore and coke platform formed on the material surface in the furnace to adjust to the optimized bimodal type or close to the central development type; When the type is the center development type, first loosen the edge gas flow, reduce the number of center coke distribution rings by more than 20%, increase the width of the coke platform by 5-20%, and then reduce the edge gas flow according to the changes to adjust to the optimized center development type or close to the flat type; When the type is a flat type, the width of the coke platform is increased by 3-10%, and the edge coal gas flow or the center coal gas flow is reduced to adjust to a better flat type with a wider coke platform.

2. The method for increasing production and reducing consumption in blast furnace smelting according to claim 1, characterized in that: During the type adjustment process, the ore-coke ratio is increased by 2-10%, and the coke consumption per ton of molten iron is reduced.

3. The method for increasing production and reducing consumption in blast furnace smelting according to claim 1, characterized in that: During the type adjustment process, the coal powder consumption is reduced by 3-15 kg / t of molten iron.

4. The method for increasing production and reducing consumption in blast furnace smelting according to claim 1, characterized in that: When the type is a bimodal type, while reducing the overdevelopment of the edge airflow, the number of center focusing rings and the amount of focus are increased or decreased according to the changes to obtain a suitable center airflow.

5. The method for increasing production and reducing consumption in blast furnace smelting according to claim 4, characterized in that: The temperature of the center point of the furnace throat gas and the temperature of the edge point of the furnace throat gas are reduced by 50-300℃, and the width of the coke platform is increased by 5-20%.

6. The method for increasing production and reducing consumption in blast furnace smelting according to claim 1, characterized in that: When the type is the central development type, the temperature of the center point of the furnace throat gas drops by 100-300°C, and the temperature of the edge point of the furnace throat gas changes by 50-150°C.

7. The method for increasing production and reducing consumption in blast furnace smelting according to claim 1, characterized in that: According to the adjusted furnace conditions, the proportion of pulverized coal in fuel consumption is increased and the proportion of coke is reduced.

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