CN201321481Y - Novel pellet cooling device - Google Patents

Abstract

The new metallized pellet cooling device adopts the supplementary nitrogen circulation cooling method, which includes the cooling machine body, feeder, intake pipe, chain grate machine and discharger. The characteristics are: the surface of the body is a metal frame structure, lined with refractory bricks in the high temperature section and the low temperature section, the high temperature end of the body is connected to the feeder, and the low temperature end is connected to the discharge device, the relative horizontal plane of the feeder and the discharge device is inclined downward, and the chain grate The machine is located in the body between the feeder and the discharger. There is an air outlet on the top of the body. The exhaust gas is recovered by the waste heat of the boiler and then returned to the cooling machine for recycling. There is a manhole on the other side for easy maintenance by operators. One side of the body is provided with multiple rows of intake pipes along the direction of material travel, and the intake pipes are connected to the main pipe of circulating gas after nitrogen supplementation. The utility model can recover heat, prevent oxidation of metallized pellets, and has the characteristics of continuous ore discharge and convenient maintenance. Suitable for cooling metallized pellets in the steel industry.

Description

A new pellet cooling device

Technical field

The utility model belongs to a cooling device in the metallurgical industry, which is mainly used for cooling metallized pellets in the iron and steel industry.

Background technique

The production of metallized pellets (direct reduced iron) by rotary hearth furnace direct reduction process is a new ironmaking process developed in the last thirty years. Because this process does not require the preparation of fuel and the deep processing of raw materials, it has a positive effect on the rational use of natural resources and the protection of the human environment, so it has received widespread attention from the metallurgical industry. Cooling is an important process of the process. The pellets at 1000°C are reduced to below 300°C, and the remaining heat is recovered to prevent the re-oxidation of the pellets and ensure the metallization rate of the product. The reduction of energy consumption in process blast furnace or converter or electric furnace is of great significance.

For continuous production, the cooling method of foreign metallized pellets is mainly indirect water-cooled open cooling, the waste heat loss is relatively large, and the temperature difference between the inlet and outlet of cooling water is only about 15°C. The cooling facility of the existing rotary hearth furnace direct reduction process in my country is an indirect water-cooled vibrating cooler developed by Beijing University of Science and Technology. Its structure is simple, but the cooling effect is poor. Metallized pellets are exposed to the air, which easily leads to secondary oxidation of the pellet surface, which affects the final metallization rate of the product. In order to further reduce the oxidation of the pellets, Japan introduces low-concentration nitrogen into the indirect water-cooled cooling cylinder to achieve the purpose of reducing the metallization rate of the pellets by continuously replenishing nitrogen, but the waste heat cannot be recycled, and the pellets are cooled in the cooling cylinder A large amount of powder appears during the turning process, which affects the quality and output of the product.

Contents of the invention

In view of the defects of existing metallized pellet cooling equipment at home and abroad, according to the actual needs of rotary hearth furnace and other direct reduced iron production, the utility model provides a cooling device capable of heat recovery, preventing oxidation of metallized pellets, and has the function of ore discharge. Continuity and maintenance-friendly metallized pellet cooling device.

The new metallized pellet cooling device adopts the supplementary nitrogen circulation cooling method, which consists of a cooler body (11), a feeder (1), an air intake main pipe (12), an air intake branch pipe (13), and a chain grate (6 ) and the discharger (9). It is characterized in that the outer surface of the body (11) is a metal frame structure, lined with refractory bricks of different high-temperature sections and low-temperature sections, the high-temperature end of the body is connected to the feeder (1), the low-temperature end is connected to the discharger (9), and the chain grate The machine (6) is located in the body (11) between the feeder (1) and the discharger (9). The top of the body is provided with an air outlet (4). Cooler recycling.

Preferably, a plurality of air inlets (16) are provided along the material advancing direction on one side of the machine body, and the air inlets (16) are connected with the air inlet branch pipe (13), and the air inlet branch pipe (13) and the nitrogen supplementary pipe (15) It is connected with the intake manifold (12), and the other side is provided with a manhole (14) for easy maintenance.

The feeder (1) is composed of a feed funnel (18) and a round roller distributor (10). The feed funnel is a heat-resistant stainless steel structure, and the inner lining is sprayed with high temperature and wear-resistant spray paint. The feed funnel (18 ) on the inclined base plate is provided with material guide ribs (17), and the inclined base plate bottom is connected with the round roller distributor (10).

The discharge device (9) is composed of a discharge funnel (19) and a movable gate (8). The discharge funnel is a steel structure, sprayed with heat-resistant and wear-resistant spray paint, and the inclined bottom plate of the discharge funnel is provided with guide ribs Bar (17), the discharge funnel is provided with a movable gate (8), one end of the movable gate (8) is connected with the cooling machine body (11), and the other end is connected with the surface of the material (2); the manhole (14) is provided with Covered with thick steel plate, the steel plate and the machine body are tightly connected together with nuts at ordinary times.

The distance between two adjacent intake branch pipes (13) on one side of the cooling machine body is 0.5-4.0 meters.

The number of intake branch pipes (13) on one side of the cooling machine body is 5-50.

The feeder (1) is inclined downward relative to the horizontal plane, and the inclination angle between the bottom edge of the feeding funnel (18) of the feeder and the vertical direction of the central axis of the round roller distributor (10) is 15-45°.

The discharger (9) is inclined downward relative to the horizontal plane, and the included angle between the movable gate (8) of the discharger and the cooling machine body (11) is 0-60°.

The relative horizontal plane of the feeder and the discharger is inclined downward, which is convenient for feeding and discharging smoothly. The stockpile formed by the natural accumulation of continuous materials can play a self-sealing effect on the inlet and outlet.

In the pellet cooling device of the utility model, the lower part of the feeder is equipped with a round roller distributor, and the lower part of the discharger is connected to the running chain plate machine, which ensures the continuous flow of materials; the natural accumulation of continuous materials and negative pressure operation realize the feeding end and The discharge end is self-sealing, and at the same time, the discharge device is equipped with a movable gate, and the angle between the discharge device and the cooling machine body is 0-60°, which also plays the role of sealing; nitrogen is used as the cooling gas, which not only plays the role of cooling, but also effectively The oxidation of the metallized pellets is avoided, and the quality of the product is guaranteed; the exhaust gas is recovered by the waste heat of the boiler, so that the waste heat can be reused. The utility model has a reasonable structure, is easy to produce, install and maintain, and can fully meet the product cooling requirements of the rotary hearth furnace direct reduction process and other direct reduced iron production processes after use. The development of production technology has great promotion significance.

Description of drawings

Fig. 1 is a schematic cross-sectional view of the utility model;

Fig. 2 is a schematic plan view of the body of the utility model in the direction of the intake pipe;

Fig. 3 is a top view schematic diagram of the utility model intake pipe;

Fig. 4 is a plan view of the utility model feeder;

Fig. 5 is a side view of the utility model feeder;

Fig. 6 is a plan view of the discharge device of the present utility model;

Fig. 7 is a side view of the utility model discharger;

Fig. 8 is a schematic plan view of the utility model manhole;

1. Feeder 2. Material 3. Metal shell 4. Air outlet 5. Refractory brick layer 6. Chain grate 7. Chain grate support 8. Movable gate 9. Discharge device 10. Roller distributor 11. Body 12. Air intake main pipe 13. Intake branch pipe 14. Manhole 15. Nitrogen supplement pipe 16. Air intake hole 17. Material guide rib 18. Feed funnel 19. Discharge funnel

Detailed ways

Example 1:

The new metallized pellet cooling device with an annual output of 100,000 tons of metallized pellets is a supplementary nitrogen circulation cooling method. , Discharge device 9 forms.

The surface of the cooling machine body 11 is a metal frame structure, with a length of 11m, a width of 2.5m, and a height of 1.8m. Different refractory bricks lining the high temperature section and the low temperature section. The high temperature end of the cooling machine is connected to the feeding funnel 18 of the feeder 1, the volume of the funnel is 0.4m ³ , the funnel 18 is made of heat-resistant stainless steel, and the inner lining is sprayed with high temperature and wear-resistant spray paint. The inclined bottom plate of the feeding funnel 18 Set up heat-resistant and wear-resistant alloy surfacing material guide ribs 17 to guide the material obliquely. The lower part uses the round roller distributor 10 to evenly distribute the material on the chain grate 6. The bottom edge of the feed funnel 18 is connected to the round roller distributor. 10 The horizontal and vertical directions of the central axis form a 45° inclination angle, and the chain grate machine is 8m long and 1.5m wide. The low temperature end of the cooling machine 11 is connected to the discharge funnel 19, the discharge funnel 19 is a steel structure, sprayed with heat-resistant and wear-resistant spray paint, and the inclined bottom plate of the discharge funnel 19 adopts heat-resistant and wear-resistant alloy surfacing ribs 17 Carry out the oblique dredging of the material, the discharge funnel 19 top board adopts movable flashboard 8, and the included angle between movable flashboard 8 and cooling machine body 11 is 35 °. The air intake branch pipe 13 and the nitrogen supplementary pipe 15 on one side of the cooling machine body are connected with the air intake main pipe 12 . The distance between the intake branch pipes 13 is 1.0 meters. There are 8 intake branch pipes 13 in quantity. The waste gas from the top of the cooling machine body is recovered by the waste heat of the boiler, and then returns to the cooling machine for recycling.

The material 2 with a temperature of 900-1100°C passes through the feeder 1, and is evenly distributed on the grate 6 under the continuous drive of the round roller distributor 10, and moves toward the discharger 9 at a constant speed. During this process, the low-temperature nitrogen gas coming in from the air inlet 16 enters the material layer and directly exchanges heat with the material 2 . After the material 2 is cooled, the temperature drops to 200-300°C, and falls onto the chain conveyor through the discharge device 9, and the continuous and stable discharge of the equipment is realized through the continuous rotation of the chain conveyor. The natural accumulation of continuous materials and the negative pressure operation realize the self-sealing of the feed end and the discharge end. At the same time, the discharge device is equipped with a movable ram, and the included angle with the cooling machine body is 0-60°, which also plays a sealing role.

Example 2:

The new metallized pellet cooling device with an annual output of 200,000 tons of metallized pellets is a supplementary nitrogen circulation cooling method. The main equipment and structure are the same as in Example 1.

The surface of the cooling machine body is a metal frame structure, 12m long, 1.5m wide, and 1.8m high. The horizontal and vertical angle between the bottom edge of the feeder and the central axis of the round roller distributor is 30°, and the length of the chain grate is 10m, and the width is 1.5m. The angle between the movable ram and the body of the cooling machine is 45°. The distance between the intake branch pipes is 1.0 meters. The number of intake branch pipes is 10

Example 3:

The new metallized pellet cooling device with an annual output of 300,000 tons of metallized pellets is a supplementary nitrogen circulation cooling method, and the main equipment and structure are the same as in Example 1.

The body surface of the cooling machine is a metal frame structure, 14m long, 3m wide, and 2m high. The horizontal and vertical angle between the bottom edge of the feeder and the central axis of the round roller distributor is 30°, the length of the chain grate is 12m, and the width is 2m. The angle between the movable ram and the body of the cooling machine is 45°. The distance between the intake branch pipes is 0.8 meters. The number of intake branch pipes is 15.

Claims (10)

1, a kind of metallized pellet refrigerating unit, adopt and replenish the nitrogen circulation type of cooling, it is made up of cooler body (11), feeder (1), inlet manifold (12), air intake branch (13), drying grate (6) and discharger (9), it is characterized in that: body (11) outside surface is a metal framework structure, the refractory brick that the liner high temperature section is different with low-temperature zone, the body temperature end connects feeder (1), low-temperature end connects discharger (9), in the body (11) of drying grate (6) between feeder and discharger, body (11) top is provided with production well (4).

2, metallized pellet refrigerating unit as claimed in claim 1, it is characterized in that: be provided with a plurality of air inlet ports (16) along the material direct of travel in body one side, air inlet port (16) links to each other with air intake branch (13), air intake branch (13) replenishes pipe (15) with nitrogen and links to each other with inlet manifold (12), and opposite side is provided with manhole (14).

3, metallized pellet refrigerating unit as claimed in claim 1, it is characterized in that: feeder (1) is made up of loading hopper (18) and circle roller distributor (10), loading hopper is the heat-resistance stainless steel structure, liner sprays with the heat resistant and wear resistant spray material, guide rib (17) is set on the inclined floor of loading hopper (18), and the inclined floor bottom is connected with circle roller distributor (10).

4, metallized pellet refrigerating unit as claimed in claim 1, it is characterized in that: discharger (9) is by going out funnel (19) and movable flashboard (8) is formed, going out funnel is steel construction, spray with the heat-resistant antifriction spray material, go out guide rib (17) is set on the funnel inclined floor, go out to be provided with on the funnel movable flashboard (8), movable flashboard (8) one ends link to each other with cooler body (11), and the other end and material (2) surface joins.

5, as each described metallized pellet refrigerating unit in the claim 1 to 4, it is characterized in that: the spacing between adjacent two air intake branches (13) is a 0.5-4.0 rice.

6, novel metal pellet refrigerating unit as claimed in claim 5, it is characterized in that: the quantity of inlet pipe is 5～50.

7, the novel metal pellet refrigerating unit of stating as claim 3, it is characterized in that: horizontal plane is downward-sloping relatively for described feeder (1), and the loading hopper of feeder (18) base is 15-45 ° with the angle of inclination of circle roller distributor (10) central axis vertical direction.

8, novel metal pellet refrigerating unit as claimed in claim 4 is characterized in that: horizontal plane is downward-sloping relatively for described discharger (9), and the movable flashboard (8) of discharger is 0～60 ° with cooler machine (11) body angle.

9, novel metal pellet refrigerating unit according to claim 6, it is characterized in that: horizontal plane is downward-sloping relatively for described feeder (1), and the loading hopper of feeder (18) base is 15-45 ° with the angle of inclination of circle roller distributor (10) central axis vertical direction.

10, novel metal pellet refrigerating unit according to claim 6 is characterized in that: horizontal plane is downward-sloping relatively for described discharger (9), and the movable flashboard (8) of discharger is 0～60 ° with cooler machine (11) body angle.

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