Intelligent OPR continuous material curtain type accurate material control method and system for full-molten-pool smelting

Abstract

The invention discloses an intelligent OPR continuous material curtain type precise material control method and system for full-molten-pool smelting, and belongs to the technical field of metallurgical submerged arc furnace kilns. Comprising a furnace top bin, and a weighing sensor is arranged on the furnace top bin; a feeding hole of the controllable continuous blanking machine is connected to a discharging hole of the furnace top stock bin; the discharging pipe system comprises a feeding pipe and a water-cooling material nozzle arranged at the tail end of the feeding pipe, the feeding end of the feeding pipe is connected to a discharging port of the controllable continuous discharging machine, and the water-cooling material nozzle extends into a hearth through a furnace cover of the submerged arc furnace and is used for scattering raw materials in an umbrella-shaped material scattering mode; the lower part of the electrode is vertically inserted and fixed in a hearth through a submerged arc furnace cover; and the closed-loop control system is in signal connection with the weighing sensor, the controllable continuous blanking machine and the electrode, and outputs a control instruction to the controllable continuous blanking machine based on weighing data, the blanking rate and the electrical parameters of the electrode, so that closed-loop interlocking control of blanking and electric energy is realized. The problems that fine particles cannot be directly fed into the furnace, the matching performance of blanking and electric energy is poor, and the automation degree is low can be solved.

Description

Technical Field

[0001] This invention belongs to the field of metallurgical submerged arc furnace technology, specifically relating to an intelligent OPR continuous material curtain precision material control method and system for full-melting pool smelting of submerged arc furnaces. Background Technology

[0002] Submerged arc furnaces are crucial smelting equipment for producing ferroalloys, calcium carbide, and yellow phosphorus. Traditional submerged arc furnaces primarily use lump ore or pellets as feed, forming a layer of material that covers the molten pool. There are typically two feeding methods: one involves feeding all at once through a feed pipe, then emptying the pipe and allowing the raw material to accumulate around the electrodes; the other involves feeding through a full feed pipe, creating a continuous material accumulation zone between the pipe and the molten pool, with the material layer varying in height depending on the molten pool conditions. Both methods are passively controlled, with the electrodes embedded below the material layer for discharge, relying on the furnace charge resistance for melting. The process flow is: furnace top hopper → feed pipe → material pile → heating layer → reaction layer → molten pool layer.

[0003] With the increasing depletion of mineral resources, the decreasing particle size of minerals, and the growing prevalence of complex, low-grade ores, traditional feeding processes have revealed numerous problems: 1) Poor permeability of the material layer, easily leading to severe material collapse and posing safety hazards; 2) Poor controllability of electrode position, resulting in uncontrollable temperature gradients; 3) Poor thermal stability, with large periodic temperature variations within the furnace; 4) Poor matching between melting speed and electrical energy, resulting in high energy consumption; 5) The need to add a large amount of auxiliary flux, causing waste of resources and energy; 6) Difficulty in adjusting the material ratio, with a delayed response; 7) Inability to form an effective interlocking control between the electrodes and the feeding process; 8) Difficulty in achieving intelligent control, as the electrode position cannot be directly observed; 9) The control precision for raw material matching can only reach the furnace secondary level (8-12 hours), failing to achieve fine-grained regulation.

[0004] Therefore, developing a submerged arc furnace smelting process that can adapt to fine-grained materials and low-grade ores, achieve precise matching of material feeding and power, and possess a high level of automation—namely, a full-melting-pool smelting intelligent OPR continuous material curtain precision material control method and system—has become a technical problem urgently needing to be solved in this field. Summary of the Invention

[0005] This invention addresses the aforementioned problems and overcomes the shortcomings of existing technologies by providing a method and system for intelligent OPR continuous material curtain precision material control in full-molten pool smelting. This system solves problems such as the inability to directly feed fine particles into the furnace, poor matching between material feeding and power supply, and low degree of automation.

[0006] To achieve the above objectives, the present invention adopts the following technical solution.

[0007] Firstly, a method for precise material control in a continuous OPR (Optical Propulsion) system for full-molten pool smelting includes the following steps: S1: The smelting raw materials are stored in the furnace top silo and transported in a non-full pipe state through the controllable continuous feeder and the feed pipe system. They are then continuously scattered into the furnace in the form of umbrella-shaped loose material through the water-cooled material nozzles set on the furnace cover of the electric arc furnace, forming a continuous dynamic material curtain that passes through the high temperature furnace gas zone from top to bottom. S2: The continuous dynamic material curtain first passes through the material curtain heating zone in the upper part of the furnace and is preheated by the high temperature furnace gas; then, the material curtain falls into the material curtain reaction zone around the electrode, where it undergoes a partial reduction reaction under the action of the electrode arc plasma, producing molten material that drips down; S3: The material dripping after step S2 falls into and maintains the full molten pool reaction zone in the lower part of the furnace. The remaining reduction reaction, melting and slag-iron separation are completed in this zone, forming a full molten pool state with no solid material pile on the upper surface. S4: Real-time acquisition of the electrical parameters of the electrodes and the real-time weighing data of the furnace top hopper; based on the preset ore-to-electricity ratio (OPR) theoretical model, dynamically adjusting the feeding rate of the controllable continuous feeder and / or the electrical energy input parameters of the electrodes through a closed-loop control system, so that the feeding rate and electrical energy input can achieve minute-level matching and interlocking control.

[0008] As a preferred embodiment of the present invention, in step S1, the spreading radius and landing height of the umbrella-shaped bulk material are controlled by adjusting the depth of the water-cooled material nozzle inserted below the furnace cover of the electric arc furnace.

[0009] As another preferred embodiment of the present invention, in step S4, the adjustment performed by the closed-loop control system includes: adjusting the feeding rate and / or feeding position in reverse according to the real-time change of electrode impedance, so that the electrode operating point tends to constant impedance control.

[0010] As another preferred embodiment of the present invention, in step S4, the real-time weighing data is obtained by a weighing sensor installed at the support of the furnace top hopper, and a soft connection is provided between the controllable continuous feeder and the feed pipe system to isolate the influence of mechanical vibration of the feed pipe system on the weighing accuracy.

[0011] As another preferred embodiment of the present invention, a metal condensation protection zone is provided at the bottom of the furnace, and a furnace wall condensation protection zone is provided on the side wall of the furnace; the smelting raw material includes fine-grained ore or low-grade ore with a particle size of less than 10 mm.

[0012] Secondly, a full-molten pool smelting intelligent OPR continuous material curtain precision material control system is provided to implement the aforementioned full-molten pool smelting intelligent OPR continuous material curtain precision material control method, comprising: A furnace top silo is used to store smelting raw materials, and a weighing sensor is installed on the furnace top silo. A controllable continuous feeder, the feed port of which is connected to the discharge port of the furnace top silo, is used to receive raw materials and provide continuous, adjustable speed feeding; The feeding pipe system includes a feeding pipe and a water-cooled nozzle located at the end of the feeding pipe. The feed end of the feeding pipe is connected to the discharge port of the controllable continuous feeder. The water-cooled nozzle extends into the furnace through the furnace cover of the electric arc furnace and is used to spread the raw materials in an umbrella-shaped bulk form. The electrode, whose lower part is vertically inserted into and fixed inside the furnace through the furnace cover of the electric arc furnace, is used to input electrical energy into the furnace and generate an electric arc; A closed-loop control system is used to connect to the weighing sensor, the controllable continuous feeder, and the electrode signal respectively. It is configured to: perform calculations based on the weighing data, the feeding rate, and the electrode electrical parameters, according to the preset mineral-to-electricity ratio (OPR) theoretical model, and output control commands to the controllable continuous feeder and / or the electrode to realize closed-loop interlocking control of feeding and electrical energy.

[0013] As another preferred embodiment of the present invention, the furnace top hopper includes a hopper body, a hopper support supporting the hopper body, and a weighing sensor disposed on the hopper support. The hopper body includes a straight section hopper and an inclined cone short hopper. The weighing sensor and the hopper support, as well as the hopper support and the hopper body, are rigidly connected to form an integral triangular weighing structure.

[0014] As another preferred embodiment of the present invention, a maintenance valve is provided between the furnace top hopper and the controllable continuous feeder; a flexible connection is provided between the controllable continuous feeder and the feed pipeline system.

[0015] As another preferred embodiment of the present invention, the water-cooled nozzle is a water-cooled structure. The water-cooled nozzle is driven by a hydraulic cylinder to change its insertion depth into the furnace. The hydraulic cylinder is connected to a closed-loop control system, and the hydraulic cylinder is controlled to move by the closed-loop control system.

[0016] As another preferred embodiment of the present invention, a metal condensation protection zone is provided at the bottom of the furnace chamber, and a furnace wall condensation protection zone is provided on the inner side wall of the furnace chamber; the raw material filling rate in the feeding pipe is controlled between 20% and 40% to maintain a non-full pipe conveying state.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: The intelligent OPR continuous material curtain precision material control method and system for full-molten pool smelting provided by this invention has the following significant advantages: 1) By continuously feeding material through a dynamic material curtain, the raw materials enter the furnace in the form of umbrella-shaped bulk materials, avoiding the problem of poor air permeability caused by traditional stockpiled materials. Fine granules (particle size <10mm) or even powders can be used directly, thus broadening the range of applicable raw materials.

[0018] 2) The feeding and power input are controlled in a closed loop through the OPR model, changing from passive adjustment to active regulation. The feeding rate can respond to the electrode parameters in minutes, achieving precise matching and significantly reducing the power consumption per ton of product.

[0019] 3) No cold material accumulation, good air permeability, wide adaptability to the moisture content of raw materials, reducing the risk of material collapse and improving operational safety.

[0020] 4) The thermal stability of the full molten pool is good, and the temperature fluctuation inside the furnace is small, which is conducive to stabilizing product quality, reducing heat loss, and improving thermal energy utilization.

[0021] 5) The batching and material adjustment are highly real-time, and the raw material ratio can be adjusted instantly based on feedback from electrical parameters, achieving minute-level material adjustment and high production flexibility.

[0022] 6) The arc heat generated by the electrodes is effectively utilized. Controllable shielding is achieved through the material curtain arc shielding, which improves the utilization rate of arc radiation heat, significantly improves the effective power factor, and reduces reactive power loss.

[0023] 7) The electrodes tend to be controlled by constant impedance, which is conducive to achieving fully automated and intelligent operation, requiring less human intervention, reducing the number of operators, and increasing the overall utilization rate of the equipment.

[0024] 8) The system has a reasonable structure, accurate weighing, and reliable control, providing technical support for the transformation of industrial furnaces towards overall intelligentization. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of an intelligent OPR continuous material curtain precision material control system for full-molten pool smelting according to the present invention.

[0026] The markings in the diagram are as follows: 1 is the weighing sensor, 2 is the furnace top hopper, 3 is the maintenance valve, 4 is the controllable continuous feeder, 5 is the flexible connection, 6 is the feeding pipe, 7 is the water-cooled feed nozzle, 8 is the material curtain heating zone, 9 is the material curtain reaction zone, 10 is the full molten pool reaction zone, 11 is the melting transition zone, 12 is the slag molten pool zone, 13 is the first molten metal pool zone, 14 is the second molten metal pool zone, 15 is the metal condensation protection zone, 16 is the furnace wall condensation protection zone, 17 is the electrode, 18 is the hopper support, 19 is the straight section hopper, and 20 is the inclined cone section hopper. Detailed Implementation

[0027] To make the technical problems solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0028] The present invention provides a method for precise material control in a continuous OPR (Optical Propulsion) system for full-molten pool smelting, which specifically includes the following steps: S1: The smelting raw materials are stored in the furnace top silo 2 and transported in a non-full pipe state through the controllable continuous feeder 4 and the feed pipe system. They are then continuously scattered into the furnace in the form of umbrella-shaped loose material through the water-cooled feed nozzle 7 set on the furnace cover of the electric arc furnace, forming a continuous dynamic material curtain that passes through the high temperature furnace gas zone from top to bottom. Specifically, by adjusting the depth of the water-cooled feed nozzle 7 inserted below the furnace cover of the electric arc furnace, the spreading radius and landing height of the umbrella-shaped bulk material are controlled. The water-cooled feed nozzle 7 serves as an intermediate device connecting the feeding pipe system and the furnace cover. It is inserted below the furnace cover into the furnace chamber, and the spreading height is adjusted to control the range of the material curtain. According to the electrical parameters of the electrode 17, its feeding point position is set, and in coordination with the electric heating zone, the material is accurately delivered to the full molten pool reaction zone 10.

[0029] S2: The continuous dynamic material curtain first passes through the material curtain heating zone 8 at the top of the furnace and is preheated by the high-temperature furnace gas; then, the material curtain falls to the material curtain reaction zone 9 surrounding the electrode 17, and undergoes a partial reduction reaction under the action of the electric arc plasma of the electrode 17, producing molten material and dripping down; The material curtain heating zone 8 mainly consists of umbrella-shaped material in the feeding state and high-temperature furnace gas. Under the action of high-temperature furnace gas with an average temperature of 1000℃, the umbrella-shaped material in the feeding state is preheated to about 600-800℃ (actual temperature depends on particle size). The material curtain reaction zone 9 mainly consists of the added umbrella-shaped material and the plasma arc of electrode 17. Under the action of electrode arc with a temperature as high as 20000℃, the preheated mixed bulk material is further heated to increase the temperature, so that a part of the mixed material undergoes a reduction reaction. In this zone, about 20-60% (actual temperature depends on particle size) of the reduction reaction is completed, and a large amount of CO gas at a temperature of about 1300℃ is generated, which partially melts the metal and drips into the full molten pool reaction zone 10.

[0030] S3: The material dripping after step S2 falls into and maintains the full molten pool reaction zone 10 in the lower part of the furnace. The remaining reduction reaction, melting and slag-iron separation are completed in this zone, forming a full molten pool state with no solid material pile on the upper surface. Specifically, the full molten pool reaction zone 10 is mainly for the mixture that has not reacted in the material curtain reaction zone 9 to continue to react and melt the unmelted metal and slag, forming a full molten pool state on the entire upper surface of the furnace. The slag and iron are separated according to the density gradient and viscosity value, producing a melt separation effect. The average temperature of the entire full molten pool zone is above 1800℃, and CO gas with a temperature of about 1500℃ will be generated during this process.

[0031] S4: Real-time acquisition of electrical parameters of electrode 17 and real-time weighing data of furnace top hopper 2; based on the preset ore-to-electricity ratio (OPR) theoretical model, dynamic adjustment of the feeding rate of the controllable continuous feeder 4 and / or the electrical energy input parameters of electrode 17 through a closed-loop control system, so that the feeding rate and electrical energy input achieve minute-level matching and interlocking control; under the control of the closed-loop control system, the controllable continuous feeder 4 can realize continuous, controllable and adjustable feeding process operation that is interlocked with the weighing data of furnace top hopper 2 and electrode 17 parameters.

[0032] Specifically, the closed-loop control system performs the following adjustments: based on the real-time changes in the impedance of electrode 17, it reversely adjusts the feeding rate and / or feeding position to make the working point of electrode 17 tend to be under constant impedance control. Specifically, the real-time weighing data is acquired by three sets of weighing sensors 1 installed at the support of the furnace top hopper 2, and a soft connection 5 is provided between the controllable continuous feeder 4 and the feed pipe system to isolate the influence of mechanical vibration of the feed pipe system on the weighing accuracy.

[0033] Specifically, a metal condensation protection zone 15 is provided at the bottom of the furnace chamber, and a furnace wall condensation protection zone 16 is provided on the side wall of the furnace chamber. The metal condensation protection zone 15 and the furnace wall condensation protection zone 16 are provided to protect the furnace lining. The smelting raw materials include fine-grained ore or low-grade ore with a particle size of less than 10 mm.

[0034] like Figure 1 As shown, below the full molten pool reaction zone 10 and between the metal condensation protection zone 15, there are sequentially a melting transition zone 11, a slag molten pool zone 12, a first metal molten pool zone 13, and a second metal molten pool zone 14. Among them, the slag molten pool zone 12, the first metal molten pool zone 13, and the second metal molten pool zone 14 after melting separation constitute the finished product molten pool zone. The slag molten pool zone 12, the first metal molten pool zone 13, and the second metal molten pool zone 14 are separated according to the density gradient and the temperature gradient to produce slag products and metal products.

[0035] Additionally, please see Figure 1 This invention provides an intelligent OPR continuous material curtain precision material control system for full-molten pool smelting, used to implement the aforementioned intelligent OPR continuous material curtain precision material control method for full-molten pool smelting, comprising: The furnace top silo 2 is used to store smelting raw materials, and a weighing sensor 1 is installed on the furnace top silo 2. The controllable continuous feeder 4 has its feed inlet connected to the discharge outlet of the furnace top hopper 2, and is used to receive raw materials and provide continuous, adjustable speed feeding. The feeding pipe system includes a feeding pipe 6 and a water-cooled nozzle 7 located at the end of the feeding pipe 6. The feed end of the feeding pipe 6 is connected to the discharge port of the controllable continuous feeder 4. The water-cooled nozzle 7 extends into the furnace through the furnace cover of the electric arc furnace and is used to spread the raw materials in the form of umbrella-shaped bulk materials. Electrode 17, the lower part of which is vertically inserted into and fixed inside the furnace through the furnace cover of the electric arc furnace, is used to input electrical energy into the furnace and generate an electric arc; The closed-loop control system is used to connect to the weighing sensor 1, the controllable continuous feeder 4 and the electrode 17 respectively. It is configured to: perform calculations based on the weighing data, feeding rate and electrode electrical parameters, according to the preset mineral-electricity ratio (OPR) theoretical model, and output control commands to the controllable continuous feeder 4 and / or the electrode 17 to realize closed-loop interlocking control of feeding and electrical energy.

[0036] Specifically, the furnace top hopper 2 includes a hopper body, a hopper support 18 supporting the hopper body, and three sets of weighing sensors 1 mounted on the hopper support 18. The hopper body includes a straight section hopper 19 and a conical section hopper 20. The weighing sensors 1 are rigidly connected to the hopper support 18, and the hopper support 18 is rigidly connected to the hopper body, forming an integral triangular weighing structure. The lower part of the weighing sensor 1 is welded to the pre-embedded parts of the plant, and the upper part of the weighing sensor 1 is connected to the hopper support 18 via bolts and nuts. The hopper support 18 is welded to the upper part of the straight section hopper 19, the straight section hopper 19 is welded to the conical section hopper 20, and the bottom of the conical section hopper 20 is welded to the outlet flange, thus forming a precise triangular weighing structure. The process function is to weigh the material in the furnace top hopper 2. The weighing sensors 1 are connected to a closed-loop control system, transmitting weighing data to the closed-loop control system in real time, and performing interlocking feedback process operations with the controllable continuous feeder 4.

[0037] Specifically, a maintenance valve 3 is provided between the furnace top hopper 2 and the controllable continuous feeder 4; a flexible connection 5 is provided between the controllable continuous feeder 4 and the feeding pipeline system. The maintenance valve 3 is used to close the feeding and unloading channels during furnace shutdown maintenance, and to perform maintenance on the controllable continuous feeder 4 below the maintenance valve 3.

[0038] Specifically, the water-cooled nozzle 7 is a water-cooled structure. The water-cooled nozzle 7 is driven by a hydraulic cylinder to change its insertion depth into the furnace. The hydraulic cylinder is connected to a closed-loop control system, which controls the operation of the hydraulic cylinder. Furthermore, the installation position of the water-cooled nozzle 7 relative to the furnace cover of the submerged arc furnace is adjustable according to actual needs.

[0039] Specifically, a metal condensation protection zone 15 is provided at the bottom of the furnace chamber, and a furnace wall condensation protection zone 16 is provided on the inner side wall of the furnace chamber. The metal condensation protection zone 15 and the furnace wall condensation protection zone 16 are provided to protect the furnace lining. The raw material filling rate in the feeding pipe 6 is controlled between 20% and 40% to maintain a non-full pipe conveying state.

[0040] In this embodiment of the intelligent OPR continuous material curtain precision material control method and system for full-molten pool smelting, the closed-loop control system includes an industrial computer, a PLC controller, and signal transmission lines. The industrial computer and the PLC controller are connected via signal lines. The PLC controller is connected to the weighing sensor 1, the controllable continuous feeder 4, and the electrode 17. The industrial computer has a preset theoretical model for the ore-to-electricity ratio (OPR). In this embodiment, the OPR setting is 2.5 t / MW·h. The closed-loop control system collects the material weight change rate (i.e., the actual feeding rate) from the weighing sensor 1 and the current and voltage signals from the electrode 17 in real time (to calculate the actual power), and calculates the actual OPR value. When the actual OPR value deviates from the set value by more than ±5%, the PLC controller automatically adjusts the frequency converter frequency of the controllable continuous feeder 4 to change the feeding rate, restoring the OPR value to the set range, thus achieving minute-level precise OPR control.

[0041] The operational results show that, using the method and system provided in this embodiment of the invention, the furnace is always kept in a fully molten pool state with no solid material pile-up, good air permeability, and no material collapse. The effective power factor reaches 0.86, which is significantly improved compared with the past. The lower limit of raw material particle size can be reduced to 5mm, achieving continuous and stable production.

[0042] The "ore-to-electricity ratio (OPR) theoretical model" described in this invention refers to a pre-established mathematical model that describes the quantitative relationship between unit electrical energy input and ore processing volume, serving as a benchmark value for the closed-loop control system.

[0043] In this invention, the ore-to-electricity ratio (OPR) is defined as the ratio of the mass of ore fed into the furnace per unit time to the active power input to electrode 17, i.e.: OPR = Q / P (Equation 1). Wherein, OPR: mineral-to-electricity ratio, in kg / (kW·h) or t / (MW·h); Q: material feed rate per unit time, which is calculated in real time by the weighing sensor 1 of the furnace top hopper 2, in kg / h or t / h; P: The active power input into the furnace by electrode 17 is calculated in real time from the voltage and current of electrode 17, and the unit is kW or MW.

[0044] In practical applications, the OPR (Ore-to-Electricity Ratio) theoretical model is established and used through the following steps: (1) Determination of the baseline OPR value: Baseline OPR value (denoted as OPR) o The specific smelting process determines the yield, and key factors include: raw material type (such as titanium concentrate, nickel ore, etc.), target product grade, type and ratio of reducing agent, and furnace type and capacity. OPR o It can be obtained through theoretical calculations or optimization using historical production data. For a given furnace type and raw materials, OPR... o It is usually a constant or a function related to the power level.

[0045] Taking titanium slag smelting as an example, when the raw material is titanium concentrate (TiO2 content 40%-53%) and the target product is 73%-92% titanium slag, the OPR (Optical Performance Ratio) is... o The empirical range for OPR is 0.7-0.9 t / (MW·h). When the raw material grade decreases or the particle size becomes finer, the OPR needs to be appropriately reduced. o To ensure a full response.

[0046] (2) Calculation of real-time OPR value: The closed-loop control system collects weighing data and electrode 17 electrical parameters every Δt time interval (Δt ranges from 10 to 60 seconds in this invention), and calculates the average feeding rate Q within the Δt time interval. avg and average active power P avg Then, the real-time OPR value is calculated: OPR real =Q avg / P avg (Equation 2); The average feeding rate Q_avg is calculated using the change in material weight ΔW of the weighing sensor 1 over a time interval Δt: Q avg = ΔW / Δt.

[0047] (3) Control logic: The closed-loop control system compares the real-time OPR value with the reference OPR value: When |OPR real -OPR o When |≤ε, the closed-loop control system maintains the current operating state; where ε is the allowable deviation threshold, usually set to OPR. o 3%-8%; When OPR real >OPR o When +ε is reached, it indicates that the material feed rate is relatively large. The closed-loop control system issues a command to reduce the speed of the controllable continuous feeder 4, thereby reducing the feed rate and causing OPR to decrease. real To OPR o return; When OPR real <OPR oWhen -ε is reached, it indicates that the electrical energy input is relatively large. The closed-loop control system can choose to: ① increase the feeding rate; ② appropriately reduce the power of electrode 17; or execute both simultaneously to make OPR... real To OPR o return.

[0048] (4) Dynamic optimization: During long-term operation, the closed-loop control system can record the OPR under different operating conditions. real The correlation between OPR and indicators such as product quality and power consumption is established through a self-learning algorithm on the benchmark OPR. o Dynamic optimization and adjustments are made to make the model more closely resemble actual production conditions.

[0049] In summary, the intelligent OPR continuous material curtain precision material control method and system for full-molten pool smelting provided by this invention is developed and designed based on production practice. It provides an effective smelting process solution for low-grade, fine-grained ores, effectively reduces the requirements of industrial furnaces for raw material particle size smelting, improves the level of automated and intelligent smelting, reduces energy consumption, and improves the overall safety and technological advancement of industrial furnace smelting operation. At the same time, it provides technical support for the development of industrial furnaces towards whole-machine intelligence.

[0050] It is understood that, although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for precise material control in intelligent OPR continuous material curtain for full-molten pool smelting, characterized in that, Includes the following steps: S1: The smelting raw materials are stored in the furnace top silo and transported in a non-full pipe state through the controllable continuous feeder and the feed pipe system. They are then continuously scattered into the furnace in the form of umbrella-shaped loose material through the water-cooled material nozzles set on the furnace cover of the electric arc furnace, forming a continuous dynamic material curtain that passes through the high temperature furnace gas zone from top to bottom. S2: The continuous dynamic material curtain first passes through the material curtain heating zone in the upper part of the furnace and is preheated by the high temperature furnace gas; then, the material curtain falls into the material curtain reaction zone around the electrode, where it undergoes a partial reduction reaction under the action of the electrode arc plasma, producing molten material that drips down; S3: The material dripping after step S2 falls into and maintains the full molten pool reaction zone in the lower part of the furnace. The remaining reduction reaction, melting and slag-iron separation are completed in this zone, forming a full molten pool state with no solid material pile on the upper surface. S4: Real-time acquisition of the electrical parameters of the electrodes and the real-time weighing data of the furnace top hopper; based on the preset ore-to-electricity ratio (OPR) theoretical model, dynamically adjusting the feeding rate of the controllable continuous feeder and / or the electrical energy input parameters of the electrodes through a closed-loop control system, so that the feeding rate and electrical energy input can achieve minute-level matching and interlocking control.

2. The intelligent OPR continuous material curtain precision material control method for full-molten pool smelting according to claim 1, characterized in that, In step S1, the spreading radius and landing height of the umbrella-shaped bulk material are controlled by adjusting the depth of the water-cooled material nozzle inserted below the furnace cover of the electric arc furnace.

3. The intelligent OPR continuous material curtain precision material control method for full-molten pool smelting according to claim 1, characterized in that, In step S4, the adjustment performed by the closed-loop control system includes: adjusting the feeding rate and / or feeding position in reverse according to the real-time change of electrode impedance, so that the electrode operating point tends to constant impedance control.

4. The intelligent OPR continuous material curtain precision material control method for full-molten pool smelting according to claim 1, characterized in that, In step S4, the real-time weighing data is acquired by a weighing sensor installed at the support of the furnace top hopper, and a flexible connection is provided between the controllable continuous feeder and the feeding pipe system to isolate the influence of mechanical vibration of the feeding pipe system on the weighing accuracy.

5. The intelligent OPR continuous material curtain precision material control method for full-molten pool smelting according to claim 1, characterized in that, The furnace bottom inside the furnace chamber is provided with a metal condensation protection zone, and the furnace sidewall inside the furnace chamber is provided with a furnace wall condensation protection zone; the smelting raw material includes fine-grained ore or low-grade ore with a particle size of less than 10 mm.

6. A smart OPR continuous material curtain precision material control system for full-molten pool smelting, characterized in that, The method for implementing the intelligent OPR continuous material curtain precision material control method for full-melting pool smelting as described in any one of claims 1 to 5 includes: A furnace top silo is used to store smelting raw materials, and a weighing sensor is installed on the furnace top silo. A controllable continuous feeder, the feed port of which is connected to the discharge port of the furnace top silo, is used to receive raw materials and provide continuous, adjustable speed feeding; The feeding pipe system includes a feeding pipe and a water-cooled nozzle located at the end of the feeding pipe. The feed end of the feeding pipe is connected to the discharge port of the controllable continuous feeder. The water-cooled nozzle extends into the furnace through the furnace cover of the electric arc furnace and is used to spread the raw materials in an umbrella-shaped bulk form. The electrode, whose lower part is vertically inserted into and fixed inside the furnace through the furnace cover of the electric arc furnace, is used to input electrical energy into the furnace and generate an electric arc; A closed-loop control system is used to connect to the weighing sensor, the controllable continuous feeder, and the electrode signal respectively. It is configured to: perform calculations based on the weighing data, the feeding rate, and the electrode electrical parameters, according to the preset mineral-to-electricity ratio (OPR) theoretical model, and output control commands to the controllable continuous feeder and / or the electrode to realize closed-loop interlocking control of feeding and electrical energy.

7. The intelligent OPR continuous material curtain precision material control system for full-molten pool smelting according to claim 6, characterized in that, The furnace top hopper includes a hopper body, a hopper support for supporting the hopper body, and a weighing sensor installed on the hopper support. The hopper body includes a straight section hopper and a short inclined cone hopper. The weighing sensor and the hopper support, as well as the hopper support and the hopper body, are rigidly connected to form an integral triangular weighing structure.

8. The intelligent OPR continuous material curtain precision material control system for full-molten pool smelting according to claim 6, characterized in that, A maintenance valve is provided between the furnace top hopper and the controllable continuous feeder; a flexible connection is provided between the controllable continuous feeder and the feed pipeline system.

9. The intelligent OPR continuous material curtain precision material control system for full-molten pool smelting according to claim 6, characterized in that, The water-cooled nozzle is a water-cooled structure. The water-cooled nozzle is driven by a hydraulic cylinder to change its insertion depth into the furnace. The hydraulic cylinder is connected to a closed-loop control system, which controls the movement of the hydraulic cylinder.

10. The intelligent OPR continuous material curtain precision material control system for full-molten pool smelting according to claim 6, characterized in that, A metal condensation protection zone is provided at the bottom of the furnace chamber, and a furnace wall condensation protection zone is provided on the inner side wall of the furnace chamber; the raw material filling rate in the feeding pipe is controlled between 20% and 40% to maintain a non-full pipe conveying state.

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