阅读说明：本技术 一种近零排放的氢冶金系统 (Hydrogen metallurgy system of near zero release ) 是由 王�锋 高建军 郦秀萍 齐渊洪 严定鎏 林万舟 于 2020-04-23 设计创作，主要内容包括：本发明涉及一种近零排放的氢冶金系统,属于冶金技术领域,解决了现有技术中钢铁冶炼排放大量废气废固、污染环境等问题。本发明氢冶金系统包括氢气还原炉(1)、气体供应与循环系统、密封输送装置(15)和高温冶炼炉(16)；所述氢气还原炉(1)用于采用氢气将铁矿原料还原为直接还原铁；所述气体供应与循环系统与氢气还原炉(1)连接,用于对氢气还原炉(1)提供氢气；所述高温冶炼炉(16)通过密封输送装置(15)与氢气还原炉(1)连接,所述密封输送装置(15)用于将直接还原铁输入送高温冶炼炉(16)。本发明氢冶金系统适用于环保的绿色冶炼工艺。(The invention relates to a near-zero emission hydrogen metallurgy system, belongs to the technical field of metallurgy, and solves the problems of solid waste, environmental pollution and the like caused by a large amount of waste gas discharged in steel smelting in the prior art. The hydrogen metallurgy system comprises a hydrogen reduction furnace (1), a gas supply and circulation system, a sealing conveying device (15) and a high-temperature smelting furnace (16); the hydrogen reduction furnace (1) is used for reducing iron ore raw materials into direct reduced iron by adopting hydrogen; the gas supply and circulation system is connected with the hydrogen reduction furnace (1) and is used for supplying hydrogen to the hydrogen reduction furnace (1); the high-temperature smelting furnace (16) is connected with the hydrogen reduction furnace (1) through a sealing conveying device (15), and the sealing conveying device (15) is used for conveying direct reduced iron to the high-temperature smelting furnace (16). The hydrogen metallurgy system is suitable for environment-friendly green smelting process.)

1. A hydrogen metallurgy system with near zero emission is characterized by comprising a hydrogen reduction furnace (1), a gas supply and circulation system, a sealed conveying device (15) and a high-temperature smelting furnace (16);

the gas supply and circulation system comprises a water-hydrogen production system (5), a second hydrogen compressor (6), a regulating valve group (7), a third hydrogen compressor (8), a heater (9) and a preheater (10);

the water hydrogen production system (5), the third hydrogen compressor (8), the preheater (10) and the heater (9) are sequentially connected, and the heater (9) is connected with the middle part of the hydrogen reduction furnace (1);

the water hydrogen production system (5), the second hydrogen compressor (6) and the regulating valve group (7) are sequentially connected, and the regulating valve group (7) is connected with the lower part of the hydrogen reduction furnace (1);

the hydrogen reduction furnace (1) is used for reducing iron ore raw materials into direct reduced iron by adopting hydrogen; the gas supply and circulation system is connected with the hydrogen reduction furnace (1) and is used for supplying hydrogen to the hydrogen reduction furnace (1); the high-temperature smelting furnace (16) is connected with the hydrogen reduction furnace (1) through a sealing conveying device (15), and the sealing conveying device (15) is used for conveying direct reduced iron to the high-temperature smelting furnace (16).

2. The near zero emission hydrometallurgical system of claim 1, wherein the gas supply and circulation system further comprises a gas purifier (2), a first water separator (3) and a first hydrogen compressor (4);

the top of the hydrogen reduction furnace (1), the coal gas purifier (2), the first dehydrator (3), the first hydrogen compressor (4) and the preheater (10) are connected in sequence; the first dehydrator (3) is also connected with a water hydrogen production system (5).

3. The near zero emission hydrometallurgical system of claim 2, characterized in that the gas supply and circulation system further comprises a blower (13), the blower (13) being used for passing air into the preheater (10).

4. The near zero emission hydrometallurgical system of claim 3, wherein the gas supply and circulation system further comprises a second water separator (11) and a stack (12);

one end of the second dehydrator (11) is connected with the preheater (10), and the other end of the second dehydrator is connected with the water hydrogen production system (5); the chimney (12) is connected with the second dehydrator (11).

5. The near-zero emission hydrometallurgical system of claim 1, further comprising a steel slag upgrading furnace (19) for upgrading high temperature liquid steel-making slag discharged from the pyrometallurgical furnace (16).

6. The system of claim 1, wherein the pyrometallurgical furnace (16) is provided with an auxiliary material addition system (17) and a recycled steel slag feed opening.

7. The near zero emission hydrometallurgical system of any one of claims 1-6, wherein the sealed conveying device (15) is lined with a heat insulating refractory material.

8. The near-zero emission hydrogen metallurgy system according to claim 1 to 6, wherein a first heat exchange tube, a second heat exchange tube and a third heat exchange tube are arranged in the preheater (10) and are respectively used for preheating air, hydrogen for combustion and hydrogen introduced into the middle of the hydrogen reduction furnace (1).

9. The near zero emission hydrometallurgical system of claim 8, wherein the preheater (10) has a low temperature preheating section and a high temperature preheating section, the first and second heat exchange tubes being in the low temperature preheating section and the third heat exchange tube being in the high temperature preheating section.

10. The near-zero emission hydrometallurgical system according to claim 8, further comprising a charging system (14) for charging iron ore raw material into the furnace from a top of the hydrogen reduction furnace (1).

Technical Field

The invention belongs to the technical field of metallurgy, and particularly relates to a near-zero emission hydrogen metallurgy system.

Background

In recent years, the environmental protection problem of the steel industry is becoming one of the key problems restricting the development of the industry, especially SO₂、NO_xAnd solid waste discharge, the existing treatment mode mainly focuses on desulfurization and denitrification of tail end flue gas and partial utilization of solid waste (wherein the steel-making slag mainly takes stockpiling as a main part), and the environmental protection problem of steel enterprises cannot be fundamentally solved.

The existing steel smelting process mainly comprises a long process of 'blast furnace-converter' taking iron ore as a raw material and an electric furnace process taking scrap steel as a raw material, wherein a blast furnace ironmaking unit comprises the working procedures of coking, sintering, pelletizing, blast furnace ironmaking and the like, a converter steelmaking unit comprises the working procedures of molten iron desulphurization, converter dephosphorization and the like, and the working procedures are complex; meanwhile, the traditional process takes carbon energy as fuel, and the carbon energy brings a large amount of CO₂、SO₂And NO_xThe pollution gas emission and the solid waste emission of a large amount of slag, dust and the like.

Disclosure of Invention

In view of the above analysis, the present invention is directed to a near zero emission hydrometallurgical system for iron and steel smelting, SO, using the present invention₂Almost has no emission, reduces the dust emission by more than 90 percent compared with the traditional process, has no waste slag emission, and is used for solving the problems of solid waste, environmental pollution and the like caused by a large amount of waste gas discharged in the steel smelting in the prior art.

The purpose of the invention is mainly realized by the following technical scheme:

a hydrogen metallurgy system with near zero emission comprises a hydrogen reduction furnace, a gas supply and circulation system, a sealed conveying device and a high-temperature smelting furnace;

the hydrogen reduction furnace is used for reducing the iron ore raw material into direct reduced iron by adopting hydrogen; the gas supply and circulation system is connected with the hydrogen reduction furnace and is used for supplying hydrogen to the hydrogen reduction furnace; the high-temperature smelting furnace is connected with the hydrogen reduction furnace through a sealing conveying device, and the sealing conveying device is used for conveying the direct reduced iron to the high-temperature smelting furnace;

the gas supply and circulation system comprises a water-hydrogen production system, a second hydrogen compressor, a regulating valve group, a third hydrogen compressor, a heater and a preheater;

the water hydrogen production system, the third hydrogen compressor, the preheater and the heater are sequentially connected, and the heater is connected with the middle part of the furnace body of the hydrogen reduction furnace;

the water hydrogen production system, the second hydrogen compressor and the regulating valve group are sequentially connected, and the regulating valve group is connected with the lower part of the furnace body of the hydrogen reduction furnace.

In one possible design, the gas supply and circulation system further comprises a gas purifier, a first dehydrator, and a first hydrogen compressor;

the top of the hydrogen reduction furnace, the coal gas purifier, the first dehydrator, the first hydrogen compressor and the preheater are sequentially connected; the first dehydrator is also connected with a water hydrogen production system.

In one possible design, the gas supply and circulation system further comprises a blower for passing air into the preheater.

In one possible design, the gas supply and circulation system further comprises a second water separator and a chimney;

one end of the second dehydrator is connected with the preheater, and the other end of the second dehydrator is connected with the water hydrogen production system; the chimney is connected with the second dehydrator.

In one possible design, the hydrogen metallurgy system further comprises a steel slag modifying furnace for modifying the high-temperature liquid steel-making slag discharged by the high-temperature smelting furnace.

In one possible design, the pyrometallurgical furnace is provided with an auxiliary material addition system and a circulating slag feed opening.

In one possible design, the sealed conveying device is lined with heat-insulating refractory material.

In one possible design, a first heat exchange tube, a second heat exchange tube and a third heat exchange tube are arranged in the preheater and are respectively used for preheating air, hydrogen for combustion and hydrogen introduced into the middle of the hydrogen reduction furnace.

In one possible design, the preheater has a low temperature preheating section and a high temperature preheating section, the first and second heat exchange tubes being in the low temperature preheating section, and the third heat exchange tube being in the high temperature preheating section.

In one possible design, the hydrogen metallurgical system further includes a charging system for charging iron ore raw material into the hydrogen reduction furnace from a top of the furnace.

Compared with the prior art, the invention can at least realize one of the following technical effects:

1) the device of the invention can replace the traditional long flow of blast furnace-converter for steel smelting, and the device of the invention needs two units of hydrogen reduction and high-temperature smelting furnace steel making, so the process can greatly reduce the production procedures and the production cost; the process uses hydrogen as a reducing agent, the product after reaction is water, and SO is not generated in the smelting process₂Discharging; in the prior art, coke, coal powder and the like are used for smelting in iron making, carburization can be carried out in iron, and the steel making process is also a decarburization process.

2) The invention changes the energy structure of the existing steel smelting process, adopts pure hydrogen to smelt the iron ore, generates water basically, does not discharge carbon dioxide, can be recycled, does not have the problems of flue gas desulfurization and denitration, does not have the problem of solid waste discharge, and is a near-zero emission hydrogen metallurgy system.

3) In the traditional process, impurities in coke and coal powder can enter iron, particularly sulfur; the process of the invention does not use carbonaceous energy and does not bring impurities caused by the carbonaceous energy, thus being more beneficial to smelting pure steel and leading the smelted pure molten steel to have higher use value.

4) The traditional iron-making process comprises at least three processes of coking, sintering, blast furnace and the like, but the iron-making process only comprises 1 process, the equipment quantity is reduced by more than 50 percent, the personnel number is reduced by more than 70 percent, and the smelting process is shorter; the process is a very environment-friendly green smelting process, and the production cost is lower in consideration of comprehensive conditions such as environmental protection treatment and the like.

5) The invention is provided with the sealed conveying device, so that the directly reduced iron discharged from the hydrogen reduction furnace can directly enter the high-temperature smelting furnace through the sealed conveying device, and the whole process is protected by inert gas to prevent the directly reduced iron from being oxidized again. In addition, because the sealed conveying device is arranged, the temperature of the directly reduced iron discharged from the hydrogen reduction furnace can be controlled to be 50-600 ℃, and the temperature can be seen to be higher, so that the requirement can be met by adopting low-temperature hydrogen for cooling without arranging a separate cooling device.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and drawings.

Drawings

The drawings are only for purposes of illustrating particular embodiments and are not to be construed as limiting the invention, wherein like reference numerals are used to designate like parts throughout.

FIG. 1 is a schematic diagram of a near zero emission hydrometallurgical system of the present invention;

FIG. 2 is a flow diagram of a near zero emission hydrometallurgical process.

Reference numerals

1-a hydrogen reduction furnace; 2-a gas purifier; 3-a first dehydrator; 4-a first hydrogen compressor; 5-a water hydrogen production system; 6-a second hydrogen compressor; 7-adjusting the valve group; 8-a third hydrogen compressor; 9-a heater; 10-a preheater; 11-a second dehydrator; 12-a chimney; 13-a blower; 14-a feeding system; 15-sealing the conveying device; 16-high temperature smelting furnace; 17-an auxiliary material adding system; 18-pure molten steel; 19-a steel slag modifying furnace; 20-a slag modifier; 21-phosphorus containing by-product.

Detailed Description

A near zero emission hydrometallurgical system is described in further detail below with reference to specific examples, which are provided for purposes of comparison and explanation only and to which the present invention is not limited.

The invention discloses a hydrogen metallurgy system with near zero emission, which comprises a hydrogen reduction furnace 1, a gas supply and circulation system, a sealing conveying device 15 and a high-temperature smelting furnace 16, wherein the hydrogen reduction furnace 1 is connected with a gas supply and circulation system; the hydrogen reduction furnace 1 is used for reducing iron ore raw materials into direct reduced iron by using hydrogen; the gas supply and circulation system is connected with the hydrogen reduction furnace 1 and is used for supplying hydrogen to the hydrogen reduction furnace 1; the high-temperature smelting furnace 16 is connected with the hydrogen reducing furnace 1 through a sealing conveying device 15, and the sealing conveying device 15 is used for conveying the direct reduced iron into the high-temperature smelting furnace 16.

The gas supply and circulation system comprises a coal gas purifier 2, a first dehydrator 3, a first hydrogen compressor 4, a water hydrogen production system 5, a second hydrogen compressor 6, a regulating valve group 7, a third hydrogen compressor 8, a heater 9, a preheater 10, a second dehydrator 11, a chimney 12 and a blower 13.

The water hydrogen production system 5, the third hydrogen compressor 8, the preheater 10 and the heater 9 are sequentially connected, and the heater 9 is connected with the middle part of the furnace body of the hydrogen reduction furnace 1; the water hydrogen production system 5, the second hydrogen compressor 6 and the regulating valve group 7 are sequentially connected, and the regulating valve group 7 is connected with the lower part of the hydrogen reduction furnace 1.

After being pressurized by a third hydrogen compressor 8, hydrogen produced by the water hydrogen production system 5 in the gas supply and circulation system enters a preheater 10 to be preheated to 700 ℃ of 300-; the other path of hydrogen passes through a second hydrogen compressor 6 and an adjusting valve group 7, the temperature of the hydrogen is (-50) DEG C-50 ℃, the hydrogen is introduced from the bottom of the hydrogen reduction furnace 1, low-temperature hydrogen is introduced from the bottom, the reduced material is cooled, meanwhile, the hydrogen is heated by the reduced high-temperature material, and the hydrogen rises to be mixed with the high-temperature hydrogen introduced from the middle part to reduce the iron ore raw material. The second part of hydrogen (i.e. the other path of hydrogen) produced by the water hydrogen production system 5 accounts for 50-70% of the water hydrogen production volume.

The temperature of the directly reduced iron discharged from the hydrogen reduction furnace 1 is 50-600 ℃, and the metallization rate of the directly reduced iron is more than 90%.

The pressure of hydrogen in the gas supply and circulation system after passing through a third hydrogen compressor 8 is 0.2-1Mpa, the pressure loss of the hydrogen after passing through a preheater 10 and a heater 9 is 0.1-0.9Mpa, and the pressure of the hydrogen entering a hydrogen reduction furnace is 0.1-0.9 Mpa; the pressure of the hydrogen after passing through the second hydrogen compressor 6 is 0.2-1Mpa, and the pressure of the hydrogen after passing through the regulating valve group 7 is 0.1-0.9 Mpa. The pressure of hydrogen entering the hydrogen reduction furnace is set to be 0.1-0.9Mpa, so that the reaction rate can be improved, too high energy consumption cannot be caused, and better economic benefit can be obtained.

The top of the hydrogen reduction furnace 1, the coal gas purifier 2, the first dehydrator 3, the first hydrogen compressor 4 and the preheater 10 are connected in sequence; the first dehydrator 3 is also connected with a water hydrogen production system 5. Gas discharged from the top of the hydrogen reduction furnace 1 passes through a gas purifier 2 and a first dehydrator 3, and water separated by the first dehydrator 3 is directly returned to a water hydrogen production system 5 for recycling; the hydrogen separated by the first dehydrator 3 is divided into two parts, the first part is mixed with the hydrogen passing through the third hydrogen compressor 8 by the first hydrogen compressor 4 and then enters the preheater 10, the second part of the hydrogen is used as fuel gas, is preheated to 50-300 ℃ by using waste heat of the preheater 10, then enters the heater 9 for combustion, and heats the hydrogen introduced into the middle part of the hydrogen reduction furnace 1 by indirect heat exchange. The second part of the hydrogen separated by the first dehydrator 3 is less than 15% of the total separated gas volume.

The blower 13 is used for introducing air into the preheater 10, one end of the second dehydrator 11 is connected with the preheater 10, and the other end of the second dehydrator is connected with the water hydrogen production system 5; the chimney 12 is connected to the second water separator 11. A blower 13 in the gas supply and circulation system heats air to 50-300 ℃ through a preheater 10, then the air enters a heater 9 to be combusted with a second part of hydrogen separated from a first dehydrator 3, high-temperature flue gas generated after combustion is used as a heat source of the preheater 10, the temperature of the flue gas discharged after passing through the preheater 10 is 100-300 ℃, the flue gas passes through a second dehydrator 11 to condense water vapor in the flue gas, the obtained water is circulated to a water hydrogen production system 5, and the rest of the flue gas is discharged from a chimney 12.

Preferably, the preheater 10 is divided into a low temperature preheating section and a high temperature preheating section, and the preheater 10 is provided with a first heat exchange tube, a second heat exchange tube and a third heat exchange tube for respectively preheating air, hydrogen for combustion and hydrogen introduced into the middle of the shaft furnace (i.e., the hydrogen reduction furnace). The first heat exchange tube and the second heat exchange tube are arranged in the low-temperature preheating section, and the third heat exchange tube is arranged in the high-temperature preheating section.

The hydrogen metallurgical system further includes a charging system 14 for charging iron ore raw material into the hydrogen reducing furnace 1 from the top thereof. A feeding system 14 at the top of the hydrogen reducing furnace 1 is used for feeding materials in a sealing manner, and gas in the furnace is not discharged outside through the feeding system; the discharge system at the bottom of the furnace is also sealed for discharging, and gas in the furnace cannot be discharged outside through the discharge opening. Illustratively, a tandem tank feeding is used, i.e., the feeding system comprises an upper tank and a lower tank which are connected in series, the upper tank is provided with an upper valve, an intermediate valve is arranged between the upper tank and the lower tank, and the lower tank is provided with a lower valve. When feeding, firstly opening an upper valve of an upper tank, feeding the material into the upper tank, then closing the upper valve of the upper tank, then opening an intermediate valve between the two tanks, and closing the intermediate valve after the material enters the lower tank; then the lower valve under the lower tank is opened to finish feeding. The discharging system has the opposite discharging sequence to the feeding sequence.

The sealed conveying device 15 is a material thermal connector between the hydrogen reduction furnace 1 and the high-temperature smelting furnace 16, a heat-preservation refractory material is lined in a closed shell, and meanwhile, non-oxidative protective gas such as nitrogen, argon and the like is introduced into the sealed shell.

The direct reduced iron discharged from the hydrogen reduction furnace 1 is sponge iron which has high activity and is easy to oxidize, the sealed conveying device 15 is arranged in the invention, so that the direct reduced iron discharged from the hydrogen reduction furnace 1 can directly enter the high-temperature smelting furnace 16 through the sealed conveying device 15, and inert gas is used for protecting the whole process to prevent the direct reduced iron from being oxidized again. In addition, because the sealed conveying device 15 is arranged, the temperature of the directly reduced iron discharged from the hydrogen reduction furnace 1 can be controlled to be 50-600 ℃, and the visible temperature can be higher, so that the requirement can be met by adopting low-temperature hydrogen for cooling without arranging a separate cooling device.

The melting temperature of the reduced iron is above 1300 ℃, and the high-temperature smelting furnace 16 is a high-temperature furnace using electric energy, such as an electric furnace, a plasma furnace, and the like. The high-temperature smelting furnace 16 is provided with an auxiliary material adding system 17 and a circulating steel slag feeding port, and pure molten steel 18 and smelting steel slag are obtained after steel making is carried out by the high-temperature smelting furnace 16.

Further, the hydrogen metallurgy system further comprises a steel slag modifying furnace 19 for modifying the high-temperature liquid steel-making slag discharged by the high-temperature smelting furnace. The steel slag modifying furnace 19 is a high temperature furnace using electric energy, such as an electric furnace, a plasma furnace, etc., the raw material of the steel slag modifying furnace 19 is high temperature liquid smelting steel slag discharged from the high temperature smelting furnace 16, and a steel slag modifier 20 is added into the furnace to realize dephosphorization of the steel slag, wherein the steel slag modifier 20 is one of pulverized coal, silicon powder, etc. by way of example. The dephosphorized new steel slag can be recycled to the high-temperature smelting furnace 16 through a recycled steel slag charging hole, the phosphorus content in the new steel slag is less than 0.5 percent, and a phosphorus-containing byproduct 21 obtained by dephosphorization can be used as a raw material for preparing ferro-phosphorus or phosphate fertilizer.

The invention also discloses a hydrogen metallurgy process with near zero emission, which comprises the following steps as shown in figure 2:

s1, feeding iron ore raw materials into the furnace from the top of the hydrogen reduction furnace 1 through a feeding system, discharging direct reduced iron from the bottom of the hydrogen reduction furnace 1 after hydrogen reduction, and introducing hydrogen into the middle part and the lower part of the furnace body of the hydrogen reduction furnace 1 respectively;

s2, discharging the directly reduced iron from the hydrogen reduction furnace 1, and conveying the directly reduced iron to the high-temperature smelting furnace 16 through a sealed conveying device;

s3, the high-temperature smelting furnace 16 melts the direct reduced iron by increasing the temperature, produces pure molten steel 18 by slagging and discharges steel-making slag;

s4, directly feeding the high-temperature liquid steel-making slag discharged from the high-temperature smelting furnace 16 into a steel slag modification furnace 19 for modification, and realizing dephosphorization of the steel slag in the modification furnace to obtain phosphorus-containing by-products 21 and new steel slag;

s5, directly circulating the new steel slag into the high-temperature smelting furnace for steel making at high temperature.

The hydrogen metallurgy system and the process of the invention are adopted to carry out steel smelting to replace energyThe device replaces the traditional long flow of a blast furnace-converter, and two units of hydrogen reduction and high-temperature smelting furnace steelmaking are needed, so the process can greatly reduce the production procedures and the production cost; the process uses hydrogen as a reducing agent, the product after reaction is water, and SO is not generated in the smelting process₂Discharging; in the prior art, coke, coal powder and the like are used for smelting in iron making, carburization can be carried out in iron, and the steel making process is also a decarburization process.

The invention changes the energy structure of the existing steel smelting process, adopts pure hydrogen to smelt the iron ore, generates water basically, does not discharge carbon dioxide, can be recycled, and has no problems of flue gas desulfurization and denitration and no problem of solid waste discharge.

In the traditional process, impurities in coke and coal powder can enter iron, particularly sulfur; the process of the invention does not use carbonaceous energy and does not bring impurities caused by the carbonaceous energy, thus being more beneficial to smelting pure steel and leading the smelted pure molten steel to have higher use value.

The traditional iron-making process comprises at least three processes of coking, sintering, blast furnace and the like, but the iron-making process only comprises 1 process, the equipment quantity is reduced by more than 50 percent, the personnel number is reduced by more than 70 percent, and the smelting process is shorter; the process is a very environment-friendly green smelting process, and the production cost is lower in consideration of comprehensive conditions such as environmental protection treatment and the like.