Blast furnace injection system and method

Abstract

The present application relates to a blast furnace by-product recovery technical field, especially to a blast furnace injection system and method, including first weighing tank, second weighing tank, sieve machine, humidifier, powder collector, injection tank and distributor; the first weighing tank, second weighing tank bottom are all equipped with valve, and the valve is connected with sieve machine through pipeline below, and the sieve machine bottom is connected with humidifier inlet pipeline; the humidifier outlet is connected with powder collector, and the powder collector bottom is connected with injection tank; the injection tank is connected with distributor pipeline, and the distributor is connected with blast furnace tuyere pipeline; while injecting pulverized coal into blast furnace, the blast furnace injection system and method can mix iron or steel making dust and coking dust, and then inject into blast furnace, which has the advantages of reducing pig iron cost, adjusting material properties, improving pig iron quality, improving productivity, reasonably using resources and protecting environment.

Description

Technical Field

[0001] This invention relates to the field of blast furnace by-product recovery technology, and in particular to a blast furnace injection system and method. Background Technology

[0002] Under the new circumstances of the steel industry's development, reducing energy consumption, saving costs, and protecting the environment have become key objectives in the ironmaking process. Injecting auxiliary fuel into the blast furnace via tuyeres has become one of the most effective measures for saving coke and improving smelting processes. Due to the rapid development and continuous improvement of blast furnace pulverized coal injection technology, it has become possible to treat other fuels through injection. Steel enterprises urgently need a method that can achieve blast furnace injection of ash from coking, ironmaking, or steelmaking processes while avoiding environmental pollution. The following is a detailed explanation of these two substances:

[0003] From an industrial analysis perspective, coking dust is very similar to anthracite in composition, both exhibiting high fixed carbon content, low volatile matter, and low sulfur content. Furthermore, coking dust has a higher calorific value than pulverized coal. Therefore, it is feasible to directly mix coking dust with raw coal and then inject it into the blast furnace, or to mix it thoroughly before injecting it into the coal mill and then into the blast furnace.

[0004] Ironmaking or steelmaking dust is a product collected by the gas dust removal system during blast furnace ironmaking and is one of the main solid wastes of steel enterprises. Dust collected by gravity dust collectors is called gravity ash, and dust collected by bag filters is called bag filter ash. It is mainly composed of oxides of Fe, C, Si, Al, Ca, and Mg, and contains low-boiling-point Pb, Zn oxides, and alkali metal oxides. It is a lightweight, fine-particle substance and one of the main solid emissions from steel enterprises. Chinese steel enterprises produce a large amount of ironmaking or steelmaking dust annually, which contains beneficial components such as iron and carbon, making it a valuable secondary resource. Today, with increasing emphasis on environmental protection and waste recycling, the reuse of ironmaking or steelmaking dust as a secondary resource has attracted growing attention.

[0005] Based on the above discussion, there is an urgent need for a blast furnace injection system and method that, while injecting pulverized coal into the blast furnace, mixes ironmaking or steelmaking dust with coking dust before injecting it into the blast furnace (adding flux and combustion aid during this process). This can achieve the goals of reducing pig iron costs, adjusting material properties, improving pig iron quality, increasing productivity, rationally utilizing resources, and protecting the environment. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, the present invention provides a blast furnace injection system and method, which mixes ironmaking or steelmaking dust and coking dust before injecting them into the blast furnace while injecting pulverized coal. This system has the advantages of reducing pig iron costs, adjusting material properties, improving pig iron quality, increasing productivity, making rational use of resources and protecting the environment.

[0007] To achieve the above objectives, the present invention employs the following technical solution:

[0008] A blast furnace injection system includes a first weighing tank, a second weighing tank, a screening machine, a humidifier, a powder collector, an injection tank, and a distributor. Valves are installed at the bottom of both the first and second weighing tanks, and the valves are connected to the screening machine via pipes below them. The bottom of the screening machine is connected to the inlet pipe of the humidifier. The outlet of the humidifier is connected to the powder collector, and the bottom of the powder collector is connected to the injection tank. The injection tank is connected to the distributor via a pipe, and the distributor is connected to the blast furnace tuyeres via a pipe.

[0009] It also includes a first belt conveyor and a second belt conveyor; one end of the first belt conveyor is connected to the screening machine, and the other end is connected to the raw coal silo in the coal powder workshop; the feed end of the second belt conveyor is connected to the humidifier, and the discharge end is connected to the powder collector.

[0010] It also includes a material flow regulating valve, the top of which is connected to the bottom of the screening machine, and the bottom of which is connected to the top of the humidifier.

[0011] It also includes a bin wall vibrator, which is fixed to the outer wall of the first weighing tank and the second weighing tank.

[0012] It also includes a nitrogen tank, which is connected to the injection tank pipeline.

[0013] It also includes a rotary feeder, which is fixed to the bottom of the spray tank and connected to the distributor pipeline.

[0014] Furthermore, a pneumatic dome valve is provided at the bottom of the powder collector.

[0015] Furthermore, the bottom valves of the first weighing tank and the second weighing tank are slide gate valves.

[0016] Furthermore, the sieve is a string sieve; the humidifier is a double-wheel stirring humidifier; and the powder collector is a bag powder collector.

[0017] A blast furnace injection method specifically includes the following steps:

[0018] 1) Add coking dust to the first weighing tank and add iron or steel dust to the second weighing tank;

[0019] 2) Based on the feedback signal from the weighing tank, the material in the weighing tank is fed into the string screen through the gate valve for screening;

[0020] 3) Particles that meet the size requirements after being screened by the string sieve proceed to the next step: passing through the material flow regulating valve and the double-wheel agitator and humidifier in sequence, and finally being conveyed to the bag filter dust collector by the second belt conveyor;

[0021] The material in the bag filter is conveyed into the injection tank through the pneumatic dome valve, and inert gas is used as the transmission tool to convey the material to the distributor, and then injected into the blast furnace through the tuyeres.

[0022] 4) Particles that do not meet the size requirements on the string screen are transported to the raw coal silo in the coal powder workshop by the first belt conveyor and enter the pulverizing process together with the coal powder.

[0023] Compared with existing technologies, the beneficial effects of this invention are:

[0024] This invention can not only add qualified coking dust, ironmaking dust, and steelmaking dust to their respective individual distributors and enter the blast furnace through the tuyeres, but also allow the large particles screened out to enter the blast furnace through the coal preparation system, thus achieving comprehensive utilization.

[0025] This invention reuses previously discarded dust from ironmaking or steelmaking and coking, greatly reducing costs and contributing to environmental protection and the achievement of national emission reduction and low-carbon goals. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure and a process flow diagram of the present invention.

[0027] In the diagram: 1-First Weighing Tank; 2-Second Weighing Tank; 3-Bin Wall Vibrator; 4-Slide Valve; 5-String Screen; 6-First Belt Conveyor; 7-Material Flow Regulating Valve; 8-Raw Coal Bunker; 9-Double-Wheel Mixing Humidifier; 10-Second Belt Conveyor; 11-Bag Filter Collector; 12-Pneumatic Dome Valve; 13-Pulse Gas Injection Tank; 14-Nitrogen Tank; 15-Rotary Feeder; 16-Distributor; 17-Tunnels; 18-Blast Furnace Detailed Implementation

[0028] This invention discloses a blast furnace injection system and method. Those skilled in the art can refer to the content of this document and appropriately modify the process parameters to achieve the desired result. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The methods and applications of this invention have been described through preferred embodiments, and those skilled in the art can clearly modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0029] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings:

[0030] like Figure 1 As shown, a blast furnace injection system includes a first weighing tank 1, a second weighing tank 2, a bin vibrator 3, a slide valve 4, a string screen 5, a first belt conveyor 6, a material flow regulating valve 7, a double-wheel agitator humidifier 9, a second belt conveyor 10, a bag filter 11, a pneumatic dome valve 12, an injection tank 13, a nitrogen tank 14, a rotary feeder 15, and a distributor 16.

[0031] The bin vibrator 3 is fixed to the outer wall of the first weighing tank 1 and the second weighing tank 2. The bottom of the first weighing tank 1 and the second weighing tank 2 are respectively provided with a gate valve 4, and the pipes after the gate valve 4 are merged into a main pipe and connected to the top inlet of the string screen 5.

[0032] The bottom outlet of the string screen 5 is connected to the flow regulating valve 7, which is connected to the top inlet of the double-wheel agitator humidifier 9. The bottom outlet of the double-wheel agitator humidifier 9 is connected to the top inlet of the second belt conveyor 10, and the bottom outlet of the second belt conveyor 10 is connected to the top inlet of the bag filter 11. The bottom of the bag filter 11 is equipped with a pneumatic dome valve 12, and the bottom outlet of the bag filter 11 is connected to the top inlet of the blow tank 13.

[0033] The injection tank 13 is connected to the nitrogen tank 14 via a pipeline. A rotary feeder 15 is provided at the bottom of the injection tank 13. The rotary feeder 15 is connected to the distributor 16 via a pipeline. The distributor 16 is connected to the air outlet 17 via a pipeline.

[0034] The feed end of the first belt conveyor 6 is located at the feed outlet of the string screen 5, and the discharge end of the first belt conveyor 6 is connected to the raw coal bunker 8 of the pulverized coal workshop.

[0035] The first weighing tank 1, the second weighing tank 2, the bag filter 11, and the spray tank 13 must all be filled with nitrogen to prevent the materials from igniting due to friction.

[0036] A blast furnace injection method specifically includes the following steps:

[0037] 1) Add coking dust to the first weighing tank 1, and add ironmaking or steelmaking dust to the second weighing tank 2; display the weight of the contents of the tank through the weighing function of the weighing tank.

[0038] 2) Based on the feedback signal from the weighing tank, the material in the weighing tank is fed into the string screen 5 through the gate valve 4 for screening.

[0039] 3) Particles that meet the size requirements after being screened by the string sieve 5 proceed to the next step: passing through the material flow regulating valve 7, the double wheel agitator and humidifier 9 in sequence, and finally being conveyed to the bag filter 11 by the second belt conveyor 10.

[0040] The material in the bag filter 11 is conveyed into the injection tank 13 through the pneumatic dome valve 12, and then conveyed to the distributor 16 using inert gas as a transmission tool, and finally injected into the blast furnace 18 through the tuyeres 17.

[0041] 4) Particles that do not meet the size requirements on the string sieve 5 are transported to the raw coal silo 8 in the coal powder workshop by the first belt conveyor 6, and will enter the pulverizing process together with the coal powder.

[0042] This invention can not only add the qualified coking dust, ironmaking dust and steelmaking dust into their respective individual distributors and enter the blast furnace 18 through the tuyeres 17, but also allow the large particles screened out to enter the furnace through the coal preparation system and finally enter the furnace through the tuyeres 17, thus achieving the purpose of comprehensive utilization.

[0043] This invention reuses previously discarded dust from ironmaking or steelmaking and coking, greatly reducing costs and contributing to environmental protection and the achievement of national emission reduction and low-carbon goals.

[0044] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A blast furnace injection system, characterized in that, It includes a first weighing tank, a second weighing tank, a screening machine, a humidifier, a powder collector, a blowing tank, and a distributor; both the first and second weighing tanks are equipped with valves at the bottom, and the valves are connected to the screening machine via pipes below them. The bottom of the screening machine is connected to the inlet pipe of the humidifier; the outlet of the humidifier is connected to the powder collector, and the bottom of the powder collector is connected to the blowing tank; the blowing tank is connected to the distributor via a pipe, and the distributor is connected to the blast furnace tuyeres via a pipe. The weight of the contents of the weighing tank is displayed through its weighing function. It also includes a material flow regulating valve, the top of which is connected to the bottom of the screening machine, and the bottom of which is connected to the top of the humidifier; It also includes a nitrogen tank, which is connected to the injection tank pipeline; It also includes a rotary feeder, which is fixed to the bottom of the spray tank and connected to the distributor pipeline; The powder collector is equipped with a pneumatic dome valve at the bottom.

2. The blast furnace injection system according to claim 1, characterized in that, It also includes a first belt conveyor and a second belt conveyor; one end of the first belt conveyor is connected to the screening machine, and the other end is connected to the raw coal silo in the coal powder workshop; the feed end of the second belt conveyor is connected to the humidifier, and the discharge end is connected to the powder collector.

3. The blast furnace injection system according to claim 1, characterized in that, It also includes a bin wall vibrator, which is fixed to the outer wall of the first weighing tank and the second weighing tank.

4. A blast furnace injection system according to claim 1, characterized in that, The bottom valves of the first weighing tank and the second weighing tank are slide gate valves.

5. A blast furnace injection system according to claim 1, characterized in that, The sieve is a string sieve; the humidifier is a double-wheel stirring humidifier; and the powder collector is a cloth bag powder collector.

6. A method based on the blast furnace injection system according to any one of claims 1 to 5, characterized in that, Specifically, the steps include the following: 1) Add coking dust to the first weighing tank and add iron or steel dust to the second weighing tank; 2) Based on the feedback signal from the weighing tank, the material in the weighing tank is fed into the string screen through the gate valve for screening; 3) Particles that meet the size requirements after being screened by the string sieve proceed to the next step: passing through the material flow regulating valve and the double-wheel agitator and humidifier in sequence, and finally being conveyed to the bag filter dust collector by the second belt conveyor; The material in the bag filter is conveyed into the injection tank through the pneumatic dome valve, and inert gas is used as the transmission tool to convey the material to the distributor, and then injected into the blast furnace through the tuyeres. 4) Particles that do not meet the size requirements on the string screen are transported to the raw coal silo in the coal powder workshop by the first belt conveyor and enter the pulverizing process together with the coal powder.

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