CN106480247B - Blast furnace operation method using thermally consolidated carbon-containing pellets as partial furnace burden - Google Patents

Abstract

The invention discloses a method for operating a blast furnace in which a new charge, that is, thermally consolidated carbon-containing pellets are used as part of the charge. According to the method, the blast furnace is operated and produced, and the novel charge thermally consolidated carbon-containing pellets can be rationally used in the blast furnace production process. Make the blast furnace run smoothly, low consumption and long life, and at the same time reduce the cost of ironmaking production and achieve economical smelting.

Description

A method of operating a blast furnace using thermally consolidated carbonaceous pellets as part of the charge

technical field

The invention belongs to the technical field of ironmaking in the iron and steel industry, and in particular relates to an operation method in which heat-solidified carbon-containing pellets are used as part of the charge and combined with the adjustment means at the lower part of the blast furnace.

Background technique

With the continuous progress and development of the society, the technology and equipment in the field of metallurgy have also shown great changes, and some new technologies have emerged, especially in the field of pre-iron, such as large-scale gas-based, coal-based reduction and other new technologies. Advanced craftsmanship and these technologies have developed rapidly in the past few years since entering the 21st century. However, with the overcapacity of iron and steel and the sluggish recovery, cost has become the core competitiveness among enterprises. As far as the current metallurgical production process is concerned, from the perspective of resources, economy and operability, the blast furnace is the most important China's advanced ironmaking process is still irreplaceable. More than 80% of the world's molten iron is still obtained through blast furnace ironmaking, and there is still technical space for further improvement in blast furnace technology. In recent years, with the deterioration of resource conditions and market reasons, some new forms of charge different from traditional charge have emerged, such as carbon-containing pellets, iron coke, cold-pressed pellets, consolidated pellets, etc., these The emergence of new charge materials makes blast furnace charge materials that could not be used in blast furnaces in the past, such as low-quality coal powder, red mud, etc., which changes the traditional form of blast furnace charge materials in the past and will also establish the development direction of the next generation of charge materials. , so that the blast furnace process is still in the process of continuous progress and development, and on the basis of its inherent advantages, it will regain its vitality. From the perspective of blast furnace production technology at home and abroad, according to their own actual situation and resource conditions, these enterprises have formed their own characteristic furnace material matching structure. Grade lump ore is the main charge structure, while some foreign companies use sinter with lump ore or self-fluxing pellets as the main charge structure, and on this basis, they have formed a blast furnace with its own characteristics operation method, and have achieved good application results.

Compared with these traditional blast furnace charges, how these new forms of charges, such as carbon-containing pellets, can be rationally applied in the blast furnace is a thorny problem that metallurgists must face in reality. As for how thermally consolidated carbonaceous pellets are used in blast furnaces, there are few reports at home and abroad. Even a small amount of references to the use of these furnace materials, such as the utilization of thermally consolidated carbonaceous pellets, are mostly visual. It is a simple ordinary pellet, which is put into the furnace in the same way as other ordinary pellets, and no in-depth research has been conducted on it after it has been put into the furnace. The problem of carbon-containing pellets being put into the furnace is solved from the perspective of the mechanism and the change of the blast furnace operation system. , China is one of the countries that proposed the new type of carbon-containing pellets earlier. There are many colleges and enterprise research and development institutions engaged in research and experiment work in this field, such as Liaoning University of Science and Technology and Northeastern University. Laboratory or semi-industrial small-scale experiments have drawn the important conclusion that thermally consolidated carbon-containing pellets are used as blast furnace charge, and its blast furnace operation system is different from the traditional operation concept of charging charge into the furnace. A similar experiment in a furnace has achieved certain results, but because the effective furnace volume of the blast furnace used for the test is too small, only a few cubic meters, it is not too much for a large blast furnace to use a new type of charge, such as thermally consolidated carbon-containing pellets. great practical reference. Most modern enterprises turn to rotary hearth furnace and other processes for production. Although the effect is good, but at the same time the problem is obvious, that is, the energy consumption is too high and it is not economically cost-effective, and blast furnace is one of the production vessels with the highest energy utilization. First, what kind of means and measures should be adopted to make the thermally consolidated carbon-containing pellets get the most reasonable use in large-scale blast furnaces at home and abroad, which is one of the most concerned issues for metallurgists at present.

At present, there is no relatively mature technology for the use of thermally consolidated carbon-containing pellets in blast furnaces. On the basis of existing conditions, a major breakthrough in the utilization technology of thermally consolidated carbonaceous pellets has not been realized.

Technical solutions

The technical problem to be solved by the present invention is to provide a new type of charge, that is, a blast furnace operation method in which thermally consolidated carbon-containing pellets are used as part of the charge, according to the needs of the future development trend of blast furnaces adopting new charge materials. In the blast furnace production process, the new type of charge is used to thermally consolidate carbon-containing pellets reasonably, so that the blast furnace can achieve stable operation, low consumption and long life, and at the same time can reduce the cost of ironmaking production and achieve economical smelting.

1. A blast furnace operation method using thermally consolidated carbon-containing pellets as part of the charge, characterized in that: thermally consolidated carbon-containing pellets are used as part of the raw material for the blast furnace, and the inclination angle of the chute on the basis of the original blast furnace design extends outward A °; The heat-consolidated carbon-containing pellets are put into the furnace alone as a charge, and the mass percentage of the addition is not allowed to exceed 30% of the mass percentage of the charge. C in the mass percentage example; and increase the length of the tuyeres in the lower hearth, the ratio of the increase in the length of the tuyeres and the ratio of the addition of thermally consolidated carbon-containing pellets to the mass percentage of the total furnace charge show a PL linear correspondence relationship; use furnace top material canned After charging in the material mode, the heat-consolidated carbon-containing pellets are arranged at the edge of the furnace throat instead of the center of the blast furnace by adopting the bell-less rotary chute distribution method, and at the same time, the heat-consolidated carbon-containing pellets are placed at the edge of the furnace throat The number of material distribution circles shall not exceed 5 circles, and the material distribution amount at the edge of the furnace throat shall not exceed 1/3 of the amount of heat-consolidated carbon-containing pellets entering the furnace; while the heat-consolidated carbon-containing pellets are entering the furnace, adjust the lower operating system, Increase the blowing air volume, and the increase ratio of the blowing air volume is the BW of the mass percentage of thermally consolidated carbon-containing pellets; reduce the amount of pulverized coal injection, and the reduction ratio of the amount of injected coal powder is the mass percentage of thermally consolidated carbon-containing pellets SC; increase the oxygen content in the blast, the increase ratio of oxygen content is the mass percentage of CO added to the thermally consolidated carbon-containing pellets, increase the hot blast temperature, and the increase ratio of the hot blast temperature is the mass percentage of the thermally consolidated carbon-containing pellets Example of ST, increase the basicity of slag, the increase in basicity ratio is the mass percentage of thermally consolidated carbon-containing pellets added to the example of AI.

The inclination and extension angle of the chute is calculated according to the following formula: A°=0.5°+HCCB×K ₁ ; the mass percentage reduction of coke in the furnace is determined according to the following formula: C=HCCB×K ₂ ; the increase ratio of tuyere length is calculated according to the following formula Carry out: PL=HCCB×K ₃ ; increase ratio of blowing air volume according to the following formula: BW=HCCB×K ₄ ; reduce ratio of injection pulverized coal volume according to the following formula: SC=HCCB×K ₅ ; oxygen content The increase ratio is carried out according to the following formula: CO=HCCB×K ₆ ; the increase ratio of hot air temperature is carried out according to the following formula: ST=HCCB×K ₇ ; the increase ratio of slag basicity is carried out according to the following formula: AI=HCCB×K ₈ .

In the formula:

HCCB: mass percentage of heat-consolidated carbon-containing pellets added, %; A°: chute inclination and extension angle, °, K ₁ , coefficient, value range 6-12; C: mass percentage of coke reduction in furnace, %, K ₂ , coefficient, value range 0.2～0.4; PL: increase ratio of tuyere length, %, K ₃ , coefficient, value range 0.2～0.4; BW: increase ratio of blast air volume, %, K ₄ , coefficient, value Range 0.2~0.4; SC: reduction ratio of pulverized coal injection, %, K ₅ , coefficient, value range 0.1~0.4; CO: oxygen content increase ratio, %, K ₆ , coefficient, value range 0.6~1.0 ; ST: hot air temperature increase ratio, %, K ₇ , coefficient, value range 0.1-0.3; AI: slag alkalinity increase ratio, %, K ₈ , coefficient, value range 0.05-0.2.

2. A blast furnace operation method using thermally consolidated carbon-containing pellets as part of the charge, characterized in that: thermally consolidated carbon-containing pellets are used as part of the raw materials for the blast furnace, and the inclination angle of the chute based on the original design of the blast furnace is extended outward A °; mixed with metallurgical coke into the furnace, when mixed, the mass percentage of thermally consolidated carbon-containing pellets added does not exceed the C of the total charge; and increase the length of the tuyere in the lower furnace hearth, and the increase in the length of the tuyere is proportional to the thermally consolidated carbon content There is a PL linear correspondence between the amount of pellets added in the percentage of the total charge mass; after charging in the furnace top tank, the thermally consolidated carbon-containing pellets are arranged in a rotary chute without a bell. The position of the central coke material column, rather than being arranged at the edge of the furnace throat or between the furnace throat and the central coke column; at the same time, the number of ore distribution circles at the edge of the furnace throat shall not exceed 3; the ore at the edge of the furnace throat shall not exceed the ore inlet. 1/3 of the furnace capacity; while the heat-consolidated carbon-containing pellets are entering the furnace, adjust the lower operating system to increase the blast volume, and the increase ratio of the blast air volume is the BW of the mass percentage of the heat-consolidated carbon-containing pellets added; reduce The amount of pulverized coal injection, the reduction range of the amount of pulverized coal injection is the SC of the mass percentage of the heat-consolidated carbon-containing pellets added; the increase of the oxygen content in the blast, the increase range of the oxygen content is the addition of heat-consolidated carbon-containing pellets The CO of the mass percentage, increase the hot blast temperature, the increasing range of the hot blast temperature is the ST of the mass percentage adding the heat-consolidated carbon-containing pellets, increase the slag basicity, and the basicity increasing range is the heat-consolidating carbon-containing pellets adding the mass percentage example AI.

The inclination and extension angle of the chute is calculated according to the following formula: A°=0.5°+HCCB×K ₁ ; the mass percentage reduction of coke in the furnace is determined according to the following formula: C=HCCB×K ₂ ; the increase ratio of tuyere length is calculated according to the following formula Carry out: PL=HCCB×K ₃ ; increase ratio of blowing air volume according to the following formula: BW=HCCB×K ₄ ; reduce ratio of injection pulverized coal volume according to the following formula: SC=HCCB×K ₅ ; oxygen content The increase ratio is carried out according to the following formula: CO=HCCB×K ₆ ; the increase ratio of hot air temperature is carried out according to the following formula: ST=HCCB×K ₇ ; the increase ratio of slag basicity is carried out according to the following formula: AI=HCCB×K ₈ .

In the formula:

HCCB: mass percentage of heat-consolidated carbon-containing pellets added, %; A°: chute inclination and extension angle, °, K ₁ , coefficient, value range 5 to 11; C: mass percentage of coke in the furnace reduced, %, K ₂ , coefficient, value range 0.2～0.3; PL: increase ratio of tuyere length, %, K ₃ , coefficient, value range 0.2～0.4; BW: increase ratio of blast air volume, %, K ₄ , coefficient, value Range 0.1~0.3; SC: reduction ratio of pulverized coal injection, %, K ₅ , coefficient, value range 0.1~0.3; CO: oxygen content increase ratio, %, K ₆ , coefficient, value range 0.6~1.0 ; ST: hot air temperature increase ratio, %, K ₇ , coefficient, value range 0.1-0.3; AI: slag alkalinity increase ratio, %, K ₈ , coefficient, value range 0.05-0.2.

Among them, the mass percentage of metallic iron in the thermally consolidated carbon-containing pellets is 5-20%, the metallization rate is 5-40%, the mass percentage of residual carbon is less than 70%, and the sum of other elements is less than 30%. %; the furnace particle size control range is 8-25cm, the compressive strength is greater than 1500N/piece, and the thermal expansion coefficient is less than 20%.

Among them, the inclination angle of the chute extends outwards, which is used to arrange the ore to the edge of the furnace throat, increase the amount of ore at the edge of the furnace throat, appropriately aggravate the edge, and reduce the scouring intensity of the edge gas flow after the thermally consolidated carbon-containing pellets are added.

Among them, increasing the length of the hearth tuyere is used to blow the central coke material column and increase the penetration of hot air in the furnace; increasing the blast volume into the furnace is used to improve the air permeability of the blast furnace dead material column and improve the forward state of the blast furnace.

Among them, due to the carbon content in the thermally consolidated carbon-containing pellets, the amount of pulverized coal injection in the blast furnace is reduced to reduce the fuel ratio and fuel consumption; the oxygen content in the blast is increased to improve the combustion of pulverized coal. Reduce fuel consumption while reducing the occurrence of bosh gas.

Among them, increasing the temperature of the hot air is used to increase the heat into the furnace and improve the combustion of pulverized coal.

Among them, due to the thermal consolidation of carbon-containing pellets into the furnace, the sulfur content in the furnace charge increases, increasing the basicity of the slag, which is used to improve the desulfurization capacity of the blast furnace and improve the operation status of the blast furnace.

According to this method to operate the blast furnace, it is possible to reasonably use the new charge to thermally consolidate carbon-containing pellets, and at the same time achieve the purpose of stable operation of the blast furnace, low consumption and long life. Among them, after using this method to operate the blast furnace, the blast furnace produces tons The consumption of iron fuel is reduced by more than 2 kg, and the production cost per ton of iron is reduced by more than 4 yuan.

Detailed ways

The present invention is further illustrated by some examples below.

Describe below in conjunction with specific embodiment:

1. Embodiment 1 (1080m ³ blast furnace of a certain iron and steel plant is illustrated as an example)

1.1 Properties of thermally consolidated carbon-containing pellets

The basic physical and chemical properties of thermally consolidated carbon-containing pellets are shown in Table 1.

Table 1 Properties of thermally consolidated carbon-containing pellets, %

A blast furnace operation method using thermally consolidated carbon-containing pellets as part of the furnace charge. The heat-consolidated carbon-containing pellets are used as a separate furnace charge instead of being mixed with other types of charge. The basic physical and chemical properties of carbon-containing pellets are shown in Table 1, and they were smelted in a blast furnace.

1.2 Furnace material collocation form

The matching form of the blast furnace charge is shown in Table 2.

Table 2 Charge matching form, %

As an independent charge, the thermally consolidated carbon-containing pellets are used as an independent charge, and the inclination of the chute extends outwards by 2°. After the charging bell distributor and the rotary chute are arranged at the specified position according to the material distribution system required by the invention, other charges are put into the furnace according to the specified charging system for blast furnace smelting. Sintered ore is 56.0%, pellet ore is 16.0%, lump ore is 4.0%, thermally consolidated carbon-containing pellet is 4.0%, and ordinary metallurgical coke is 20.0%.

1.3 Changes in operating system

See Table 3 for changes in the blast furnace operating system.

Table 3 Changes in operating system

The thermally consolidated carbon-containing pellets are put into the blast furnace as an independent charge. In order to adapt to the smelting work of the new charge, the operation system of the blast furnace needs to be changed accordingly. On the basis of the original blast furnace, the length of the tuyere is increased by 12cm, and the air volume Increased by 77m ³ /min, increased oxygen enrichment rate by 0.02%, decreased coal injection ratio by 2.0kg/t, increased air temperature by 26°C, and correspondingly increased slag alkalinity. Correspondingly, the weight edge operation system was adopted to adapt to the new blast furnace operation system.

1.4 Implementation effect of blast furnace

After the blast furnace uses thermally consolidated carbon-containing pellets as part of the charge, the smelting effect of the blast furnace is shown in Table 4.

Table 4 Effect of blast furnace after implementation

When thermally consolidated carbon-containing pellets are used as part of the blast furnace charge, this method can be used for blast furnace smelting, which can increase output, reduce fuel ratio, improve gas utilization, achieve stable blast furnace operation, and finally achieve the effect of reducing ironmaking production costs and purpose.

2. Embodiment 2 (1080m ³ blast furnace in a steel plant is taken as an example)

2.1 Properties of thermally consolidated carbon-containing pellets

The basic physical and chemical properties of thermally consolidated carbon-containing pellets are shown in Table 5.

Table 5 Properties of thermally consolidated carbon-containing pellets, %

A blast furnace operation method using heat-consolidated carbon-containing pellets as part of the furnace charge. The heat-consolidated carbon-containing pellets and coke are mixed into the furnace. The basic physical and chemical properties of the heat-consolidated carbon-containing pellets are analyzed in Table 5, performing blast furnace smelting.

2.2 Furnace material collocation form

See Table 6 for the matching form of the furnace charge into the blast furnace.

Table 6 Charge matching form, %

The heat-consolidated carbon-containing pellets and coke are mixed into the hopper, and the inclination angle of the chute is extended outward by 4°, and are transported to the top of the blast furnace through the main belt, and passed through the bellless distributor and the rotary chute according to the requirements of the invention After the material distribution system is arranged at the designated position, the other furnace materials are put into the furnace according to the designated charging system for blast furnace smelting. Among them, the furnace material matching form is determined according to the mass percentage of the furnace materials, of which sinter is 56.0%, and pellets are 10.0% %, 4.0% for lump ore, 10.0% for thermally consolidated carbon-containing pellets, and 20.0% for ordinary metallurgical coke.

2.3 Changes in the operating system

See Table 7 for changes in the blast furnace operating system.

Table 7 Operating System Changes

The thermally consolidated carbon-containing pellets and coke are mixed into the blast furnace. In order to adapt to the smelting work of the new charge, the operation system of the blast furnace needs to be changed accordingly. On the basis of the original blast furnace, the length of the tuyere is increased by 16cm, and the air volume is increased by 70m. ³ /min, the oxygen enrichment rate increased by 0.04%, the coal injection ratio decreased by 3.5kg/t, the hot blast temperature increased by 30°C, and the slag alkalinity increased accordingly. Correspondingly, the operating system of increasing central coking was adopted to adapt to the new blast furnace operation system.

2.4 Implementation effect of blast furnace

After the blast furnace adopts thermally consolidated carbon-containing pellets as part of the charge, the smelting effect of the blast furnace is shown in Table 8.

Table 8 Effect of Blast Furnace Implementation

When thermally consolidated carbon-containing pellets are used as part of the blast furnace charge, this method can be used for blast furnace smelting, which can increase output, reduce fuel ratio, improve gas utilization, achieve stable blast furnace operation, and finally achieve the effect of reducing ironmaking production costs and purpose.

3 Embodiment 3 (a steel plant 2600m ³ blast furnace is taken as an example)

3 Properties of thermally consolidated carbon-containing pellets

The basic physical and chemical properties of thermally consolidated carbon-containing pellets are shown in Table 9.

Table 9 Properties of thermally consolidated carbon-containing pellets, %

A blast furnace operation method using thermally consolidated carbon-containing pellets as part of the furnace charge. The heat-consolidated carbon-containing pellets are used as a separate furnace charge instead of being mixed with other types of charge. The basic physical and chemical properties of carbon-containing pellets are shown in Table 9, and they were smelted in a blast furnace.

3.2 Furnace material collocation form

See Table 10 for the matching form of the blast furnace charge.

Table 10 Charge matching form, %

As an independent charge, the thermally consolidated carbon-containing pellets are used as an independent charge, and the inclination of the chute is extended outward by 3°. After the charging bell distributor and the rotary chute are arranged at the specified position according to the material distribution system required by the invention, other charges are put into the furnace according to the specified charging system for blast furnace smelting. Sintered ore is 50.0%, pellet ore is 0.0%, lump ore is 0.0%, thermally consolidated carbon-containing pellet is 30.0%, and ordinary metallurgical coke is 20.0%.

3.3 Changes in the operating system

See Table 11 for changes in the blast furnace operating system.

Table 11 Operating System Changes

The thermally consolidated carbon-containing pellets are put into the blast furnace as an independent charge. In order to adapt to the smelting work of the new charge, the operation system of the blast furnace needs to be changed accordingly. On the basis of the original blast furnace, the length of the tuyere is increased by 15cm, and the air volume Increased by 126m ³ /min, increased oxygen enrichment rate by 0.07%, decreased coal injection ratio by 8.0kg/t, increased air temperature by 25°C, and correspondingly increased slag alkalinity. Correspondingly, the weight edge operation system was adopted to adapt to the new blast furnace operation system.

3.4 Implementation effect of blast furnace

After the blast furnace adopts thermally consolidated carbon-containing pellets as part of the charge, the smelting effect of the blast furnace is shown in Table 12.

Table 12 Effect of Blast Furnace Implementation

When thermally consolidated carbon-containing pellets are used as part of the blast furnace charge, this method can be used for blast furnace smelting, which can increase output, reduce fuel ratio, improve gas utilization, achieve stable blast furnace operation, and finally achieve the effect of reducing ironmaking production costs and purpose.

4 Embodiment 4 (a steel plant 2600m ³ blast furnace is taken as an example)

4.1 Properties of thermally consolidated carbon-containing pellets

The basic physical and chemical properties of thermally consolidated carbon-containing pellets are shown in Table 13.

Table 13 Properties of thermally consolidated carbon-containing pellets, %

A blast furnace operation method using heat-consolidated carbon-containing pellets as part of the furnace charge. The heat-consolidated carbon-containing pellets and coke are mixed into the furnace. The basic physical and chemical properties of the heat-consolidated carbon-containing pellets are analyzed in Table 13, performing blast furnace smelting.

4.2 Furnace material collocation form

See Table 14 for the matching form of the furnace charge into the furnace.

Table 14 Charge matching form, %

The heat-consolidated carbon-containing pellets and coke are mixed into the hopper, and the inclination angle of the chute is extended outward by 3°, and are transported to the top tank of the blast furnace through the main belt, and passed through the bellless distributor and the rotary chute according to the requirements of the invention After the material distribution system is arranged at the designated position, other furnace materials are put into the furnace according to the designated charging system for blast furnace smelting. Among them, the furnace material matching form is determined according to the mass percentage of the furnace materials, of which sinter is 56.0%, and pellets are 0.0% %, 4.0% for lump ore, 20.0% for thermally consolidated carbon-containing pellets, and 20.0% for ordinary metallurgical coke.

4.3 Changes in the operating system

See Table 15 for changes in the blast furnace operating system.

Table 15 Operating System Changes

The thermally consolidated carbon-containing pellets and coke are mixed and put into the blast furnace. In order to adapt to the smelting work of the new charge, the operation system of the blast furnace needs to be changed accordingly. On the basis of the original blast furnace, the length of the tuyere is increased by 20cm, and the air volume is increased by 110m. ³ /min, the oxygen enrichment rate increased by 0.10%, the coal injection ratio decreased by 5.0kg/t, the hot blast temperature increased by 35°C, and the slag alkalinity increased accordingly. Correspondingly, the operation system of increasing central coking was adopted to adapt to the new blast furnace operation system.

4.4 Implementation effect of blast furnace

After the blast furnace uses thermally consolidated carbon-containing pellets as part of the charge, the smelting effect of the blast furnace is shown in Table 16.

Table 16 Effect of Blast Furnace Implementation

When thermally consolidated carbon-containing pellets are used as part of the blast furnace charge, this method can be used for blast furnace smelting, which can increase output, reduce fuel ratio, improve gas utilization rate, achieve stable blast furnace operation, and finally reduce ironmaking production costs. the goal of.

5 Embodiment 5 (3800m ³ blast furnace of a certain iron and steel plant is illustrated as an example)

5.1 Properties of thermally consolidated carbon-containing pellets

The basic physical and chemical properties of thermally consolidated carbon-containing pellets are shown in Table 17.

Table 17 Properties of thermally consolidated carbon-containing pellets, %

A blast furnace operation method using thermally consolidated carbon-containing pellets as part of the furnace charge. The heat-consolidated carbon-containing pellets are used as a separate furnace charge instead of being mixed with other types of charge. The basic physical and chemical properties of the carbon-containing pellets are shown in Table 17, and they were smelted in a blast furnace.

5.2 Furnace material collocation form

See Table 18 for the matching form of the blast furnace charge.

Table 18 Charge matching form, %

As an independent charge, the thermally consolidated carbonaceous pellets are used as an independent charge, and the inclination angle of the chute is extended outward by 4°. After the charging bell distributor and the rotary chute are arranged at the specified position according to the material distribution system required by the invention, other charges are put into the furnace according to the specified charging system for blast furnace smelting. Sintered ore is 45.0%, pellet ore is 10.0%, lump ore is 5.0%, thermally consolidated carbon-containing pellet is 20.0%, and ordinary metallurgical coke is 20.0%.

5.3 Changes in the operating system

See Table 19 for changes in the blast furnace operating system.

Table 19 Operating System Changes

The thermally consolidated carbon-containing pellets are put into the blast furnace as an independent charge. In order to adapt to the smelting work of the new charge, the operation system of the blast furnace needs to be changed accordingly. On the basis of the original blast furnace, the length of the tuyere is increased by 15cm, and the air volume Increase by 160m ³ /min, increase oxygen enrichment rate by 0.14%, reduce coal injection ratio by 6.0kg/t, increase air temperature by 27°C, and correspondingly increase slag alkalinity. Correspondingly adopt the weight edge operation system to adapt to the new blast furnace operation system.

5.4 Implementation effect of blast furnace

After the blast furnace uses thermally consolidated carbon-containing pellets as part of the charge, the smelting effect of the blast furnace is shown in Table 20.

Table 20 Effects of Blast Furnace Implementation

When thermally consolidated carbon-containing pellets are used as part of the blast furnace charge, this method can be used for blast furnace smelting, which can increase output, reduce fuel ratio, improve gas utilization rate, achieve stable blast furnace operation, and finally reduce ironmaking production costs. the goal of.

6 Embodiment 6 (3800m ³ blast furnace of a certain iron and steel plant is illustrated as an example)

The basic physical and chemical properties of thermally consolidated carbon-containing pellets are shown in Table 21.

Table 21 Properties of thermally consolidated carbon-containing pellets, %

A blast furnace operation method using heat-consolidated carbon-containing pellets as part of the furnace charge. The heat-consolidated carbon-containing pellets and coke are mixed into the furnace. The basic physical and chemical properties of the heat-consolidated carbon-containing pellets are analyzed in Table 21, performing blast furnace smelting.

6.2 Furnace Charge Matching Form

See Table 22 for the matching form of the furnace charge into the furnace.

Table 22 Charge matching form, %

The heat-consolidated carbon-containing pellets and coke are mixed into the hopper, and the inclination angle of the chute is extended outward by 2.5°, and are transported to the top of the blast furnace through the main belt, and passed through the bellless distributor and the rotary chute according to the requirements of the invention After the material distribution system is arranged at the designated position, other furnace materials are put into the furnace according to the designated charging system for blast furnace smelting. Among them, the furnace material matching form is determined according to the mass percentage of the furnace material, of which sinter is 60.0%, and pellets are 5.0% %, 0.0% for lump ore, 10.0% for thermally consolidated carbon-containing pellets, and 20.0% for ordinary metallurgical coke.

6.3 Changes in the Operating System

See Table 23 for changes in the blast furnace operating system.

Table 23 Operating System Changes

The thermally consolidated carbon-containing pellets and coke are mixed into the blast furnace. In order to adapt to the smelting work of the new charge, the operation system of the blast furnace needs to be changed accordingly. On the basis of the original blast furnace, the length of the tuyere is increased by 25cm, and the air volume is increased by 120m. ³ /min, the oxygen enrichment rate increased by 0.10%, the coal injection ratio decreased by 8.0kg/t, the hot blast temperature increased by 20°C, and the slag alkalinity increased accordingly, and the operation system of increasing central coking was adopted accordingly to adapt to the new blast furnace operation system.

6.4 Implementation effect of blast furnace

After the blast furnace uses thermally consolidated carbon-containing pellets as part of the charge, the smelting effect of the blast furnace is shown in Table 24.

Table 24 Effect of Blast Furnace Implementation

When thermally consolidated carbon-containing pellets are used as part of the blast furnace charge, this method can be used for blast furnace smelting, which can increase output, reduce fuel ratio, improve gas utilization rate, achieve stable blast furnace operation, and finally reduce ironmaking production costs. the goal of.

Claims (1)

1. a kind of using hot consolidation carbonaceous pelletizing as the method for operating blast furnace of part furnace charge, it is characterised in that：Hot consolidation contains carbon ball Group is used as blast furnace part material, chute inclination angle on the basis of original BF Design, to A ° of extension；By hot consolidation carbonaceous pelletizing Enter stove separately as a kind of furnace charge, percent mass ratio is added and does not allow more than the 30% of quality of furnace charge percentage, feeding density It is the C that percent mass ratio is added in hot consolidation carbonaceous pelletizing that charcoal amount, which reduces percent mass ratio,；And it is long to increase lower part cupola well air port Degree, air port length increases ratio and hot consolidation carbonaceous pelletizing addition accounts for the two presentation PL lines between total quality of furnace charge percentage Property correspondence；After being fed using furnace roof batch can charging method, using no bell swivel chute distributing mode into being about to hot consolidation Carbonaceous pelletizing is arranged into furnace throat edge, while the cloth number of turns of the hot consolidation carbonaceous pelletizing in furnace throat edge must not exceed 5 circles, Furnace throat edge cloth doses must not exceed the 1/3 of hot consolidation carbonaceous pelletizing furnace entering volume；While hot consolidation carbonaceous pelletizing enters stove, Lower part operating duty is adjusted, the blow rate required is increased, it is that percent mass ratio is added in hot consolidation carbonaceous pelletizing to blast air quantity to increase ratio BW；Coal powder blowing amount is reduced, it is the SC that percent mass ratio is added in hot consolidation carbonaceous pelletizing that coal injection amount, which reduces ratio,；Increase Add oxygen content in air blast, it is the CO that percent mass ratio is added in hot consolidation carbonaceous pelletizing that oxygen content, which increases ratio, increases hot wind temperature Degree, it is the ST that percent mass ratio is added in hot consolidation carbonaceous pelletizing that hot blast temperature, which increases ratio, increases basicity of slag, and basicity increases Ratio is the AI that percent mass ratio is added in hot consolidation carbonaceous pelletizing；

Its chute inclination angle extension angle is carried out by following formula：A °=0.5 °+HCCB × K₁；Feeding density charcoal reduces mass percent Example is carried out by following formula：C=HCCB × K₂；Air port length increases ratio and is carried out by following formula：PL=HCCB × K₃；It blasts Air quantity increases ratio to be carried out by following formula：BW=HCCB × K₄；Coal injection amount reduces ratio and is carried out by following formula：SC= HCCB×K₅；Oxygen content increases ratio and is carried out by following formula：CO=HCCB × K₆；Hot blast temperature increase than press following formula into Row：ST=HCCB × K₇；Basicity of slag increases ratio to be carried out by following formula：AI=HCCB × K₈；

In formula：

HCCB：Percent mass ratio, % is added in hot consolidation carbonaceous pelletizing；A°：Chute inclination angle extension angle, °, K₁, coefficient, value Range 6~12；C：Feeding density charcoal reduces percent mass ratio, %, K₂, coefficient, value range 0.2~0.4；PL：Air port length Increase ratio, %, K₃, coefficient, value range 0.2~0.4；BW：It blasts air quantity and increases ratio, %, K₄, coefficient, value range 0.2~0.4；SC：Coal injection amount reduces ratio, %, K₅, coefficient, value range 0.1~0.4；CO：Oxygen content increases ratio Example, %, K₆, coefficient, value range 0.6~1.0；ST：Hot blast temperature increases ratio, %, K₇, coefficient, value range 0.1~ 0.3；AI：Basicity of slag increases ratio, %, K₈, coefficient, value range 0.05~0.2.