Process method for cooling metallurgical high-temperature hot material by stepping cooler

Abstract

The invention discloses a process method for cooling metallurgical high-temperature hot materials through a stepping cooler, relates to the technical field of ferrous metallurgy, and aims to solve the problem that wet-process slag treatment equipment has too many drawbacks. The stepping cooler comprises a bed body and a shell, the shell is installed above the bed body in a covering mode, the shell is a heat preservation shell, and the heat preservation shell is installed above the bed body in a covering mode. An inclined fixed bed, a plurality of rows of stepping moving beds which are horizontally arranged and an outlet grid section are sequentially arranged on the bed body, the stepping moving beds are installed on the bed body through guide rails, and a hydraulic system used for driving the stepping moving beds to move on the bed body is installed below the stepping moving beds. The bed body is further provided with a tug and a bracket which are used for supporting the stepping moving bed. The scheme is a brand new scheme for completely replacing a steel metallurgy steelmaking hot splashing method, a hot stuffy slag method and a drum method wet treatment process, and is also an alternative scheme for a traditional ring type cooler and a belt type cooler for metallurgy hot material hot sintering ore and hot pellet ore.

Description

Technical Field

[0001] The invention relates to the technical field of iron and steel metallurgy, in particular to a process method for cooling high-temperature hot metallurgical materials with a step-type cooler. Background Art

[0002] At present, in the domestic and foreign iron and steel metallurgical production processes, the hot steel slag at about 1350℃ in the steelmaking converter is generally treated with wet water cooling methods such as water quenching slag, hot pouring method, hot stuffing method and drum method in the off-furnace slag treatment process. The wet slag treatment method has unsafe production problems such as large water consumption, dusty steam polluting the environment, low heat recovery efficiency, and easy explosion during operation. There is no technical precedent for using walking bed full dry air cooling to cool hot steel slag in domestic and foreign iron and steel metallurgical production. Similarly, there is no precedent for the full dry walking bed cooling process for hot pellets and hot sintered ores in domestic and foreign iron and steel metallurgy, and the commonly used specifications range from 120-650m 2 Ring cooler or belt cooler is used to cool the hot sintered ore with a particle size of no more than 150mm and a temperature of no more than 850℃, hot pelletized ore of about 600℃ and other materials after roasting and crushing to ≤100℃+ambient temperature. Its main structural form is blast ring cooler (or belt cooler), and the nominal effective cooling area is generally 140-650m 2 (With cooling machine ≥50m 2 ), the rotation center diameter of the ring cooler trolley is 22-59m (the inclined length of the belt cooler is ≥50m), the cooling ring speed is 0.4-1.2r / h, the trolley width is 2.6-4.0m, the thickness of the sintering material layer on the trolley is 1.4-1.5m, the normal processing capacity of hot sintered ore is 310-1500t / h (the pelletizing belt cooler is ≥100t / h), and the blast air volume is 682000-3300000m 3 / h(Pellet cooler 2000-2500m 3 / t ore), which complies with the standard content and characteristics of JB / T5509 SHG type ring cooler. It occupies a large area, has a long cooling time (the hot material cooling route is about ≥50m), an air leakage rate of ≥5%, and a high investment that restricts its technological progress. Summary of the invention

[0003] In order to solve the above problems, that is, to solve the problems raised by the above background technology, the present invention proposes a process method for cooling metallurgical high-temperature hot materials with a walking cooler, comprising a bed and a shell, the shell being installed on the bed, the shell being a heat-insulating shell, an inclined fixed bed, a horizontally arranged multi-row walking moving bed and an outlet grate bar being sequentially arranged on the bed, the walking moving bed being installed on the bed through a guide rail, a hydraulic system for driving the walking moving bed to move on the bed being installed below the walking moving bed, and a tug and a bracket for supporting the walking moving bed being also arranged on the bed;

[0004] The bed body is provided with a cooling fan group connected thereto, and the air duct of the cooling fan group is arranged below the fixed bed and the stepping movable bed for conveying cooling air upwards, and the shell is installed with a waste heat recovery device for collecting high-temperature heat carried by the cooling air.

[0005] A plurality of longitudinal sealing components are arranged between each row of the stepping moving bed.

[0006] The present invention is further configured as follows: the guide rail is also provided with a glycerine lubrication system for conveying glycerine to reduce friction.

[0007] The present invention is further configured as follows: the following steps are performed using a step-by-step cooler: high-temperature hot materials (or crushed whole particles) are put into a step-by-step bed cooler, the high-temperature hot materials first enter the fixed bed of the slope section for cooling, and then enter the horizontally arranged moving step-by-step bed of the transmission section for cooling, the conveying mode of each row of the moving step-by-step bed is synchronously driven by two front and rear hydraulic cylinders, and each row is relatively independent, and the step-by-step cooler achieves the purpose of conveying clinker by alternating reciprocating motion between rows; the grate plates of the fixed bed and the grate plates of the moving step-by-step bed are both ventilated with cooling air, the cooling air passes through the high-temperature hot material layer, and completes high-efficiency heat exchange with the high-temperature material to achieve the purpose of cooling the high-temperature hot material; the cooling air brings the high-temperature heat to the waste heat recovery device for collection, which is used for heat exchange to produce steam or generate electricity after the waste heat flue gas is recovered.

[0008] The present invention is further configured as follows: the high-temperature hot material is steel slag, pelletized ore or sintered ore, the material layer of the high-temperature hot material has a particle size ≥9-39mm accounting for 80%, a particle size <6mm≤5% and a particle size >50mm≤8%, and the material layer thickness is 0.5-1.2m.

[0009] The beneficial technical effects of the present invention are as follows: this scheme completely replaces the hot pouring method, hot smoldering slag method, and drum wet treatment process scheme for steel metallurgy, and is also an alternative to the traditional ring cooler and belt cooler for hot sintered ore and hot pelletized ore of metallurgical hot materials. The stepping bed cooling and waste heat recovery process method can be used to exchange heat with cold air in the unit volume of the trolley for gas-solid heat exchange between the hot materials with heat storage capacity on the stepping bed, thereby ensuring the need for cooling the hot materials and the conditions for maximizing the recovery of the waste heat of the hot ore after the cooling air of the blower group exchanges heat with the hot ore. For the thick material layer of hot ore in the front, middle and end sections of the stepping bed, the resistance of the material layer is overcome by increasing the air volume and pressure difference of the blower (or reducing the stepping speed of the trolley), thereby ensuring that the hot ore is cooled to below 100°C and the transportation function of the heat-resistant equipment is required. A high-temperature flue gas recovery pipeline is set in the front, middle and end sections of the stepping bed to further increase the temperature and volume of the collected high-temperature flue gas. This solution can enable the installed blower fan group to meet the needs of maximizing the recovery of waste heat from exhaust gas under different air volume and pressure difference conditions. Therefore, this solution has good economic and social benefits and has a very good promotion effect in the market. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 The overall structural diagram of this scheme is shown.

[0011] Figure 2 A schematic diagram of the fixed bed and stepping moving bed structure is shown.

[0012] Figure 3 The schematic diagram of the process flow of this scheme is shown.

[0013] Figure 4 A schematic diagram of the material conveying principle of a stepping moving bed is shown.

[0014] Figure numerals: 1. fixed bed, 2. stepping moving bed, 3. shell, 4. longitudinal sealing assembly, 5. tugboat, 6. bracket, 7. hydraulic system, 8. guide rail, 9. outlet grate, 10. waste heat recovery device. DETAILED DESCRIPTION

[0015] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0016] The present invention proposes a process for cooling high-temperature hot materials in metallurgy by a step-type cooler. The nominal effective cooling area of ​​the step-type cooler (step-type cooler for short) is in the range of 12-200m 2, aspect ratio 5-10, the material layer thickness of hot material or slag or ore (particle size ≥9-39mm accounts for 80%, particle size <6mm≤5%, particle size >50mm≤8%) on the trolley is 0.5-1.2m, the stroke frequency is 0-15 times / min, the stroke is in the range of 220~500mm±20~50mm, and the daily cooling hot material output is 300-9000t.

[0017] After entering the end of the production process, the hot materials of iron and steel metallurgical production after physical and chemical reaction processes are continuously and evenly distributed to the fixed and movable beds of the step-type cooler through the loading (or transportation) facilities. The high-temperature hot materials first enter the fixed bed 1 of the slope section for cooling, and then enter the movable step-type bed 2 of the horizontal transmission section for cooling. The cooling fan group sends the cooling air to the grate plate of the fixed bed 1 and the bottom of the movable step-type bed 2. The cold air enters the hot mineral material from bottom to top and conducts a fully and even gas-solid heat exchange with it. The hydraulic system 10 consists of two front and rear hydraulic cylinders. The conveying mode of each row of stepping moving beds 2 is synchronously driven by two front and rear hydraulic cylinders, and each row is relatively independent. The stepping cooler achieves the purpose of conveying clinker by alternating reciprocating motion between rows. After the hot ore is gradually cooled, it steps forward to discharge the cold material to the outlet grate 15 for unloading; the grate plates of the fixed bed 1 and the stepping moving bed 2 are both ventilated with cooling air, and the cooling air passes through the high-temperature hot material layer and completes high-efficiency heat exchange with the high-temperature material to achieve the purpose of cooling the high-temperature hot material; the cooling air brings the high-temperature heat to the waste heat recovery device 10 for collection, which is used for waste heat recovery or power generation.

[0018] When the mobile stepping bed is running, all the columns move forward together, driving the material forward, and then all the columns retreat in three batches, namely "1 in 3 out", in the manner of "1 in 3 out" in order. Due to the friction between the clinkers, the front clinker is unloaded at the discharge port. The stepping mobile cooler achieves the purpose of conveying clinker through such alternating reciprocating motion between columns. There is cooling air ventilation under the grate plates of the stepping bed and the mobile stepping grate bed. The cooling air passes through the high-temperature material layer, completes heat exchange with the high-temperature material, and takes out the heat for waste heat utilization or power generation (12-50kWh / t of power generation per ton of hot mineral material), thereby achieving the purpose of cooling the metallurgical hot material to recover heat. The fixed bed and the horizontal moving stepping bed are composed of several columns respectively, and the cooling fan group provides cooling air to cool the hot material.

[0019] The main structure of the blast stepping bed cooler includes a blast fixed combined heat-resistant stepping bed, a blast movable combined stepping bed, a bed unit and longitudinal sealing components, a supporting wheel device, a heat preservation furnace and a sealing device, an air cannon system, a hydraulic station and a transmission system, a glycerin lubrication system, a cooling fan group and an air supply pipeline system, a frame assembly, a sealing device, a feeding device, a feeding dust removal device, an unloading funnel, an air leakage dust removal hood at the unloading location, and a high-temperature flue gas waste heat recovery and collection device.

[0020] A process method for cooling metallurgical high-temperature hot materials with a step-type cooler can realize cooling of hot materials (steel slag, pellets, sintered ore, etc.) in a certain particle size range of 1350±50℃ (to 350±50℃) in metallurgical production to ≤100℃+ambient temperature, and has small footprint, easy layout and low investment.

[0021] The fixed stepping air cooling bed is composed of a single module made by casting heat-resistant alloy steel, and the mobile stepping air cooling bed is composed of steel plate forging.

[0022] A process method specially used for cooling high-temperature hot materials in metallurgy and recovering waste heat by using a step-type cooler. It is a new solution that completely replaces the hot pouring method, hot smoldering method, and drum wet treatment process of steel metallurgy. It is also an alternative to the traditional ring coolers and belt coolers for hot sintered ore and hot pelletized ore of metallurgical hot materials. The step-bed cooling and waste heat recovery process method can ensure the need for cooling hot materials and maximize the recovery of waste heat of hot ore after the cooling air of the blower group exchanges heat with the hot ore through gas-solid heat exchange with the cold air within the unit volume of the trolley. For the thick layer of hot ore in the front, middle and end sections of the step-bed, the resistance of the material layer is overcome by increasing the air volume and pressure difference of the blower (or reducing the stepping speed of the trolley), thereby ensuring that the hot ore is cooled to below 100°C and the transportation function of heat-resistant equipment is required. The high-temperature flue gas recovery pipeline is set on the front and middle insulation cover of the stepping bed, which further improves the temperature and volume of the collected high-temperature flue gas. This solution can make the set blower fan group meet the needs of maximum waste heat recovery under different air volume and pressure difference conditions. Therefore, this solution has good economic and social benefits, and has a very good promotion effect in the market.

[0023] The fully dry air-blast stepping bed cooler cools hot materials in the field of iron and steel metallurgy. The fully dry cooling process does not require water, and the material layer thickness of the hot material or steel slag or pelletized ore, sintered ore (particle size ≥9-39mm accounts for 80%, particle size <6mm≤5%, particle size >50mm≤8%) on the cooling trolley is 0.5-1.2m.

[0024] The high-temperature hot material (or crushed whole grain) first enters the slope section heat-resistant fixed cooling bed for cooling through the arranged stepping bed cooler, and then enters the horizontally arranged transmission section mobile stepping bed for cooling. The conveying mode of each row of stepping beds is synchronously driven by the front and rear two hydraulic cylinders. Each row is relatively independent. The stepping cooler achieves the purpose of conveying clinker by alternating reciprocating motion between rows.

[0025] Both the fixed bed grate plates and the moving stepping grate bed grate plates are ventilated with cooling air. The cooling air passes through the high-temperature material layer, completes high-efficiency heat exchange with the high-temperature material, and brings out the high-temperature heat for waste heat recovery, thereby achieving the purpose of cooling the metallurgical hot material.

[0026] Although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0027] In the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0028] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] The term "comprise" or any other similar term is intended to cover a non-exclusive inclusion, such that a process, article, or apparatus / device that includes a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, article, or apparatus / device.

[0030] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A step-type cooler for cooling metallurgical high-temperature hot materials, comprising a bed and a shell (3), wherein the shell (3) is mounted on the bed, characterized in that: The shell (3) is a heat-insulating shell, and an inclined fixed bed (1), a plurality of horizontally arranged stepping moving beds (2) and an outlet grate (9) are sequentially arranged on the bed body, and the stepping moving bed (2) is mounted on the bed body via a guide rail (8). A hydraulic system (7) for driving the stepping moving bed (2) to move on the bed body is installed below the stepping moving bed (2), and a tug (5) and a bracket (6) for supporting the stepping moving bed (2) are also arranged on the bed body (2); The bed body is provided with a cooling fan group connected thereto, and the air duct of the cooling fan group is arranged below the fixed bed (1) and the stepping moving bed (2) for conveying cooling air upwards. The shell (3) is provided with a waste heat recovery device (10), and the waste heat recovery device (10) is used to collect high-temperature heat carried by the cooling air. A plurality of longitudinal sealing components (4) are arranged between each row of the stepping moving bed (2).

2. A step-type cooler for cooling metallurgical high-temperature hot materials according to claim 1, characterized in that: The guide rail (8) is also provided with a glycerine lubrication system for conveying glycerine to reduce friction.

3. A process for cooling metallurgical high-temperature hot materials using a step-type cooler, characterized in that: The step cooling machine according to claim 1 is used to perform the following steps: S1: High-temperature hot materials (or crushed whole particles) are put into a stepping bed type cooler. The high-temperature hot materials first enter the fixed bed (1) in the slope section for cooling, and then enter the moving stepping bed (2) in the horizontal transmission section for cooling. The conveying mode of each row of the moving stepping bed (2) is synchronously driven by two front and rear hydraulic cylinders. Each row is relatively independent. The stepping cooler achieves the purpose of conveying clinker by alternating reciprocating motion between rows. S2: The grate plates of the fixed bed (1) and the grate plates of the stepping moving bed (2) are both ventilated with cooling air. The cooling air passes through the high-temperature hot material layer and completes high-efficiency heat exchange with the high-temperature material to achieve the purpose of cooling the high-temperature hot material; S3: The cooling air carries the high-temperature heat to the waste heat recovery device (10) for collection, and is used for heat exchange to produce steam or generate electricity after the waste heat flue gas is recovered.

4. The process for cooling metallurgical high-temperature hot materials by a step-type cooler according to claim 3, characterized in that: The high temperature hot material is steel slag, pelletized ore or sintered ore, the material layer of the high temperature hot material has a particle size of ≥9-39mm accounting for 80%, a particle size of <6mm≤5% and a particle size of >50mm≤8%, and a thickness of 0.5-1.2m.

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