Blast furnace top dust collection system and collection method

Abstract

The invention belongs to the technical field of blast furnace smelting, and relates to a blast furnace top dust collecting system which comprises a receiving hopper, a sealing structure and a single dust remover. The sealing structure comprises a modularized frame, a sealing panel, a gap sealing piece and a skip car channel, the modularized frame is installed at the top of the receiving hopper, the modularized frame is covered with the sealing panel, a buffer layer is arranged on the inner side of the sealing panel, and the gap sealing piece is arranged in a gap between the modularized frame and the sealing panel; a skip car channel is arranged at the bottom of the receiving hopper, and a soft curtain or an automatic door system is arranged at an opening of the skip car channel. And the receiving hopper is connected to a single dust remover through a dust removal pipeline. The invention further relates to a blast furnace top dust collecting method. Through the collaborative design of the sealing structure and the single dust remover, the dust collecting efficiency can reach 99% or above, no dust overflows visually, and the working environment is greatly improved.

Description

Technical Field

[0001] This invention belongs to the field of blast furnace smelting technology, and relates to a dust collection system and method, particularly a dust collection system and method for the top of a blast furnace. Background Technology

[0002] Dust pollution in the blast furnace top receiving hopper area has been a long-standing problem in blast furnace smelting production. The root causes mainly include the following three aspects: Material characteristics cause dust: Blast furnace raw materials (such as iron ore powder and coke powder) are inherently brittle. During loading, unloading, transfer and falling into the receiving hopper, they are easily broken, generating a large amount of fine dust, forming a dust pollution source.

[0003] Airflow causes diffusion: There is a continuous upward airflow at the top of the blast furnace, which carries dust generated in the receiving hopper area outward, causing fugitive emissions and polluting the surrounding working environment.

[0004] The equipment design has limitations: the traditional blast furnace receiving hopper has a simple structure and poor sealing performance. It usually relies on rubber curtains or simple cover plates for basic sealing, which cannot effectively block the spread of dust. At the same time, the receiving area is often not equipped with a dedicated dust removal system, or due to factors such as narrow site space and high construction difficulty, it is difficult to integrate into the existing blast furnace dust removal network, which further aggravates dust pollution.

[0005] To address the above problems, several solutions have emerged in the existing technology, but all of them have obvious drawbacks: Dust collection pipeline renovation plan: A large number of dust collection pipelines need to be laid on the top and around the blast furnace. This not only involves a large amount of work and high investment costs, but also requires long-term shutdowns during construction, which seriously affects the normal production rhythm of the blast furnace and has a negative impact on the economic benefits of the enterprise.

[0006] Simple sealing measures: Simply adding sealing curtains, covers, etc. to improve the sealing of the receiving hopper has very limited effect. Dust will still overflow from the gaps in the equipment, and the problem of dust diffusion cannot be fundamentally solved.

[0007] Regular water spraying dust suppression solution: Water spraying in the material receiving area suppresses dust, but water spraying can cause raw materials to become wet and clump together, changing their physical properties and affecting the stability of the subsequent blast furnace smelting process; at the same time, moisture will accelerate equipment corrosion, shorten equipment lifespan, and increase equipment maintenance costs.

[0008] Therefore, developing an efficient, economical, easy-to-implement blast furnace top dust collection system and method that does not affect the normal production of blast furnaces has become an urgent need in the field of environmental protection transformation of blast furnaces. Summary of the Invention

[0009] The purpose of this invention is to overcome the shortcomings of the prior art and provide a dust collection system and method for blast furnace top, so as to achieve efficient dust collection without large-scale modification of the original structure of the blast furnace, reduce investment and operating costs, and at the same time ensure the stability of blast furnace production.

[0010] The technical problem solved by this invention is achieved through the following technical solution: A dust collection system for the top of a blast furnace, comprising a receiving hopper, characterized in that it includes a sealing structure and a single dust collector; The sealing structure includes a modular frame, a sealing panel, a gap seal, and a material cart channel. The modular frame is installed on the top of the receiving hopper, and the sealing panel is covered on the modular frame. A buffer layer is provided on the inner side of the sealing panel, and a gap seal is provided between the modular frame and the sealing panel. A material cart channel is provided at the bottom of the receiving hopper, and a soft curtain or automatic door system is provided at the opening of the material cart channel. The receiving hopper is connected to a single dust collector via a dust removal pipe.

[0011] Moreover, the modular frame is made of welded steel profiles, the sealing panel is made of steel plate or wear-resistant composite material, the buffer layer is made of rubber, and the gap seal is made of silicone rubber or polyurethane sealing strip.

[0012] Moreover, the aforementioned single dust collector is a pulse jet cartridge dust collector.

[0013] Furthermore, the electrical connections of the individual dust collector are designed to be explosion-proof and are connected to the existing power supply system of the blast furnace.

[0014] A method for collecting dust from the top of a blast furnace, characterized by comprising the following steps: S1: First, accurately measure the dimensions of the receiving hopper, the material car, and the space of the furnace top platform to determine the shape of the sealing structure and the installation position of the dust collector. Then, prefabricate the frame, panel, and core components of the dust collector in the factory. Subsequently, use the short-term shutdown time of the blast furnace to install the sealing structure, dust collector, pipelines, and electrical lines on site. Finally, check the sealing performance of the sealing structure and test the air volume, negative pressure value, and ash removal system function of the dust collector. S2: The system automatically starts and stops or runs continuously according to the blast furnace charging procedure. The dust collector parameters can be observed through the control panel or remote monitoring system. When the pressure difference increases, the individual dust collector is automatically cleaned. S3: Every 3-4 months, take advantage of the blast furnace maintenance time to shut down the individual dust collector and open the ash hopper valve of the individual dust collector to release ash and recycle the dust. Replace the filter cartridges in the individual dust collector after 1-2 years of use. Regularly check the sealing structure and repair damaged parts. When maintaining, disconnect the power supply and implement the tagging and locking system. Operators should wear protective equipment.

[0015] Furthermore, in step S1, the sealing structure frame is fixed first during on-site installation, and then the sealing panel and sealing strip are assembled; in step S2, the clean gas emission concentration is less than 10 mg / m³.

[0016] Furthermore, in step S3, the recovered dust is returned to the sintering process.

[0017] The advantages and beneficial effects of this invention are as follows: The dust collection system and method for the top of this blast furnace, through the synergistic design of "sealed structure + individual dust collector", can achieve a dust collection efficiency of over 99%. The dust concentration in the receiving area has been reduced from over 50 mg / m³ before the modification to below 5 mg / m³. The emission concentration is far below the requirement of 10 mg / m³ in the "Emission Standard of Air Pollutants for Iron and Steel Sintering and Pelletizing Industry" (GB 28665-2012). Visually, there is no dust overflow, which greatly improves the working environment.

[0018] The main energy consumption of this invention is the power consumption of the fan and control system and the consumption of compressed air, with monthly electricity costs of only a few thousand yuan; the maintenance cost is low, requiring only regular ash removal and occasional filter cartridge replacement; the recovered dust can be returned to the sintering process, reducing raw material loss; at the same time, it avoids environmental fines, extends the service life of the equipment, and indirectly creates economic benefits.

[0019] The system of this invention adopts a modular design, which can be installed within a short period of blast furnace shutdown, with a short construction period and minimal impact on production; and the design can be adjusted according to the site space and blast furnace scale, which is highly flexible and especially suitable for the renovation of old blast furnaces.

[0020] This invention is applicable to dust control at the top of blast furnaces of all sizes, and can also be extended to dust collection scenarios in other metallurgical industries (such as converters and electric furnaces), making it highly valuable for promotion. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the system of the present invention. Detailed Implementation

[0022] The present invention will be further described in detail below through specific embodiments. The following embodiments are merely descriptive and not limiting, and should not be used to limit the scope of protection of the present invention.

[0023] A dust collection system for blast furnace roof mainly consists of three parts: a sealing structure, a single dust collector, and supporting equipment. These parts work together to form a complete dust collection and purification process. Sealed structure: As the first line of defense for dust collection, it is used to confine the dust in the receiving hopper area to a local space, providing favorable conditions for subsequent dust removal.

[0024] Structural components: Includes a modular frame welded from steel profiles, a sealing panel covering the frame, gap seals, a material cart passage, and observation and maintenance doors. The frame is made of stainless steel and fixed to the foundation surrounding the receiving hopper; the sealing panel is made of steel plate or wear-resistant composite material, with an inner buffer layer to reduce noise and material impact; gaps are dynamically sealed using silicone rubber or polyurethane sealing strips; the material cart passage is slightly larger than the material cart's outline, and the passage entrance is equipped with a soft curtain or automatic door system; the maintenance door is used for routine inspection and maintenance.

[0025] Design principles: Completeness: Cover the area around the receiving hopper to the maximum extent possible, leaving only the necessary openings for the material cart to enter and exit; Durability: High-temperature resistant (adaptable to the high-temperature environment of the blast furnace top) and wear-resistant materials are used to ensure long-term stable use; Flexibility: The structure is adjustable to accommodate deviations in material cart operation and thermal expansion and contraction of the equipment; Safety: It does not affect the normal operation and emergency maintenance procedures of the blast furnace.

[0026] Individual dust collector: The core purification unit of the system, responsible for drawing in dust-laden gas within the sealed area and filtering and purifying it. A pulse-jet cartridge dust collector is selected, and the specific design is as follows: Core parameters and components: Air volume: determined based on the volume of the sealed space, the opening area, and the dust generation rate, typically 5000-10000 m³ / h, to ensure that the sealed area maintains a slight negative pressure and prevents dust from overflowing; Filter cartridge: Made of polyester or membrane-coated filter cartridge, it can withstand temperatures up to 120℃, with high filtration accuracy and large dust holding capacity, ensuring dust removal efficiency; Structural components include: an air inlet located at the bottom of the dust collector (connected to the top of the sealing structure or multiple suction points), vertically installed filter cartridges (for easy cleaning and replacement), a bottom ash hopper (with a level gauge and manual / automatic ash discharge valve), an induced draft fan (located behind the dust collector to provide system power), a pulse cleaning system (including a compressed air tank, pulse valves and controllers, for periodic pulse cleaning), and a PLC control system (monitoring parameters such as differential pressure and temperature, and automatically alarming when abnormal).

[0027] Installation requirements: Individual dust collectors should be placed as close as possible to the sealed structure to shorten the length of the dust extraction pipe and reduce pressure loss; the diameter of the dust extraction pipe should be designed according to the air volume to avoid sharp bends and reduce resistance; electrical connections should be connected to the existing power system of the blast furnace and adopt an explosion-proof design to adapt to the harsh environment at the furnace top.

[0028] Supporting equipment includes dust extraction pipes connecting the sealing structure and the individual dust collector, valves for controlling airflow, and monitoring devices for dust concentration and system pressure to ensure stable system operation and controllable status.

[0029] Based on the above system, the present invention also provides a method for collecting dust from the top of a blast furnace, the seven innovations of which include the following steps: System installation phase On-site measurement: Accurately measure the dimensions of the receiving hopper, material cart, and furnace top platform space to determine the shape of the sealing structure and the installation position of the dust collector; Prefabricated modules: The sealed frame, panels and core components of the dust collector are fabricated in the factory, reducing the amount of on-site construction work; On-site installation: Utilize the short-term downtime of the blast furnace (without affecting the production rhythm), first fix the sealing structure frame, then assemble the sealing panel and sealing strip, and then install the dust collector and connecting pipes and electrical lines; Commissioning: Check the sealing structure for airtightness, adjust the gaps to ensure there are no major leaks; start the dust collector, test the air volume, negative pressure value and dust removal system function, and ensure that the system parameters meet the standards.

[0030] System operation phase Start-up: The system starts and stops automatically with the blast furnace charging program, or runs continuously as needed; Real-time monitoring: Observe parameters such as differential pressure, air volume, and temperature of the dust collector through the control panel or remote monitoring system. When the differential pressure increases, the pulse cleaning system is triggered to automatically clean the dust. Dust purification: Dust-laden gas is drawn from the sealed area into the dust collector by the induced draft fan. After being filtered by the filter cartridge, the clean gas is discharged through the fan in compliance with the emission standard (emission concentration is less than 10mg / m³). The dust is trapped on the surface of the filter cartridge and falls into the ash hopper through pulse jet cleaning.

[0031] System maintenance phase Regular ash discharge: Every 3-4 months, during the blast furnace maintenance period, the dust collector is turned off and the ash hopper valve is opened to discharge the dust into the ash storage bag or ash transport vehicle. The collected dust can be returned to the sintering process for recycling. Filter cartridge replacement: The service life of the filter cartridge is usually 1-2 years (adjusted according to the characteristics of the dust). Replacement can be done by simply opening the dust collector's inspection door, which is easy to operate. Sealing inspection: Regularly inspect the sealing structure panel and sealing strip for damage, repair them in time, and ensure sealing performance; Safe operation: During maintenance, the system power must be disconnected, the tagging and locking system must be implemented, and operators must wear protective equipment such as dust masks and goggles to avoid direct contact with the surface of high-temperature equipment.

[0032] Taking a 1000m³ blast furnace top dust collection renovation project as an example, the implementation process of this invention is as follows: On-site survey and design: The diameter of the receiving hopper is 3.5m and the dimensions of the material cart (length × width × height) are 6m × 2.2m × 1.8m. The sealing structure is determined to be a cylindrical frame (diameter 4.2m, height 5m). A modular frame welded from 304 stainless steel is selected. The sealing panel is made of 10mm thick wear-resistant steel plate with a 5mm thick rubber buffer layer on the inside. The gaps are sealed with silicone rubber sealing strips. The dimensions of the material cart passage are designed to be 6.2m × 2.4m, and wear-resistant rubber soft curtains are installed at the passage opening.

[0033] Selection of individual dust collectors: Based on the volume of the sealed space and the dust generation rate, the air volume of the dust collector is determined to be 8000m³ / h. A pulse jet filter cartridge dust collector (12 filter cartridges, filter cartridge specifications φ320×600mm, polyester membrane material) is selected and matched with a 45kW induced draft fan. The PLC control system is connected to the original central control system of the blast furnace.

[0034] Installation and commissioning: During the 3-day shutdown maintenance of the blast furnace, the sealing structure frame was fixed, the panel was assembled, the dust collector was installed, and the pipeline was connected. During the commissioning phase, the negative pressure value of the sealing area was tested and found to be stable at -50Pa, the differential pressure of the dust collector was controlled at 800-1200Pa, the cleaning cycle was set to 5 minutes / time, and the emission concentration was tested at 4.2mg / m³, which met the design requirements.

[0035] Operation and maintenance: After the system is put into operation, it will run automatically with the blast furnace charging program. The parameters are monitored monthly through the remote monitoring system. Ash discharge is carried out every 3 months during the blast furnace maintenance (about 5 tons of dust are recovered each time and returned to the sintering process). The filter cartridge is replaced after 18 months of use. The maintenance process only takes 2 hours and does not affect blast furnace production.

[0036] Results Verification: One year after the project was put into operation, the dust concentration in the receiving area stabilized at 3-5 mg / m³, and the investment payback period was 8 months, achieving a dual improvement in environmental and economic benefits.

[0037] Although embodiments and drawings of the present invention have been disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, variations and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A blast furnace top dust collection system, comprising a receiving hopper, characterized in that: Includes sealing structure and individual dust collector; The sealing structure includes a modular frame, a sealing panel, a gap seal, and a material cart channel. The modular frame is installed on the top of the receiving hopper, and the sealing panel is covered on the modular frame. A buffer layer is provided on the inner side of the sealing panel, and a gap seal is provided between the modular frame and the sealing panel. A material cart channel is provided at the bottom of the receiving hopper, and a soft curtain or automatic door system is provided at the opening of the material cart channel. The receiving hopper is connected to a single dust collector via a dust removal pipe.

2. The blast furnace top dust collection system according to claim 1, characterized in that: The modular frame is made of welded steel profiles, the sealing panel is made of steel plate or wear-resistant composite material, the buffer layer is made of rubber, and the gap seal is made of silicone rubber or polyurethane sealing strip.

3. The blast furnace top dust collection system according to claim 1, characterized in that: The aforementioned single-unit dust collector is a pulse-jet cartridge dust collector.

4. A collection method based on the blast furnace top dust collection system according to any one of claims 1-3, characterized in that: Includes the following steps: S1: System installation. First, accurately measure the dimensions of the receiving hopper, material car, and furnace top platform space to determine the shape of the sealing structure and the installation position of the dust collector. Then, prefabricate the frame, panel, and core components of the dust collector in the factory. Subsequently, use the short-term shutdown time of the blast furnace to install the sealing structure, dust collector, pipelines, and electrical wiring on site. Finally, check the sealing performance of the sealing structure and test the dust collector's air volume, negative pressure value, and ash removal system function. S2: System operation. The system starts and stops automatically or runs continuously according to the blast furnace charging program. The dust collector parameters can be observed through the control panel or remote monitoring system. When the pressure difference increases, the individual dust collector is automatically cleaned. S3: System maintenance. Every 3-4 months, take advantage of the blast furnace maintenance time to shut down the individual dust collectors and open the ash hopper valves of the individual dust collectors to release ash and recycle the dust. Replace the filter cartridges in the individual dust collectors after 1-2 years of use. Regularly inspect the sealing structure and repair damaged parts. During maintenance, disconnect the power supply and implement the tagging and locking system. Operators must wear protective equipment.

5. The collection method of a blast furnace top dust collection system according to claim 4, characterized in that: In step S1, the sealing structure frame is fixed first during on-site installation, and then the sealing panel and sealing strip are assembled; in step S2, the clean gas emission concentration is less than 10 mg / m³.

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