A flash furnace gas distribution system and gas distribution smelting method

Abstract

The invention provides a flash furnace gas distribution system, including a gas distribution tower connected to the outlet of the flash furnace gas supply device, the tower body is located in the flash furnace reaction tower, the gas distribution tower is a multi-layer structure, the inner diameter of each layer of the tower body gradually decreases from top to bottom, and a gap is left at the connection between two adjacent tower bodies. The invention has a reasonable structural design, the mineral powder dispersed and dropped from the feeding device will be impacted multiple times by the multi-layer airflow blown out from the gap between the tower bodies of each layer of the gas distribution tower, and is continuously stirred by power, so that the mineral powder is uniformly dispersed rapidly, and after leaving the gas distribution tower, an excellent dispersion state can be obtained.

Description

Technical Field

[0001] The invention belongs to the technical field of smelting metal oxide ores, and in particular relates to a flash furnace gas distribution system and a gas distribution smelting method. Background Art

[0002] The flash furnace originally used for metal sulfide ores is expanded to be used for smelting metal oxide ores (such as iron concentrate). The existing patented technology (patent number: CN105925809A) has made improvements to the flash furnace. It introduces a coal gasification system and uses the thermal energy, kinetic energy and chemical energy carried by coal gas to make space reduction smelting feasible. The idea of ​​solving the problem of this technology is: as long as the output of coal gas is increased, the amount of ore can be increased simultaneously, thereby increasing the output in proportion. However, the actual situation is not the case. The main reason is that when the amount of ore and coal gas increases to a certain extent, the processing capacity depends on the mixing degree of ore powder and gas. Only when the gas and solid are mixed evenly can the added ore powder react quickly. However, a major difficulty of the flash smelting process is how to improve the uniformity of gas-solid mixing. In a high-temperature environment where power equipment cannot be used, how to control and change the mixing state of gas and ore powder particles is a problem that professionals in the field of flash metallurgy have been studying and looking for better solutions. The existing technology cannot make the gas-solid mixing reach the optimal state, and there is always room for improvement. Summary of the invention

[0003] In view of this, the present invention aims to overcome the defects in the above-mentioned prior art and proposes a flash furnace gas distribution system.

[0004] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0005] A flash furnace gas distribution system includes a gas distribution tower connected to the outlet of the flash furnace gas supply device. The tower body is located in the flash furnace reaction tower. The gas distribution tower is a multi-layer structure. The inner diameter of each layer of the tower body gradually decreases from top to bottom, and a gap is left between two adjacent tower bodies at the connection part.

[0006] Furthermore, the vertical section of each layer of the tower body is roughly triangular.

[0007] Furthermore, the cross section of each layer of the tower body is circular.

[0008] Furthermore, the number of connecting rods between every two layers of the tower body is 3-12.

[0009] Furthermore, the side of the connecting rod facing the center of the gas distribution tower has the largest cross section, and its cross section gradually shrinks to a linear shape toward the outside of the gas distribution tower.

[0010] Furthermore, the feeding device is arranged as a feeding nozzle in an annular feeding manner, or a plurality of point-type feeding nozzles are evenly distributed in the circumferential direction of the feeding device.

[0011] Furthermore, point burners are arranged in a ring shape around the periphery of the feeding device.

[0012] Furthermore, the working range of the gas pressure sprayed by the gas supply device is 0.2kg / cm 2 Up to 50kg / cm 2 .

[0013] A method for gas distribution smelting using the above-mentioned flash furnace gas distribution system:

[0014] 1) Several feeding devices and burners are arranged near the gas supply device installed at the top of the reaction tower;

[0015] 2) The high-pressure gas supplied from the gas supply device enters the gas distribution tower, and the gas is ejected from the gap at the connection part of the multi-layer tower body of the gas distribution tower and cuts into the smelting space of the flash furnace reaction tower;

[0016] 3) When adding materials, the mineral powder is impacted by the airflow sprayed from the gas distribution tower many times during its descent, and is quickly dispersed, so that the mineral powder can contact the reaction airflow sprayed from the gas distribution system with a larger specific surface area;

[0017] 4) Fuel and oxygen-containing gas are sprayed into the burner and burned fully to supplement the heat required for smelting in the flash furnace reaction tower space.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] The invention has a reasonable structural design. The mineral powder dispersed and dropped from the feeding device is impacted multiple times by the airflow blown out from the gaps between the tower bodies of each layer of the gas distribution tower, and is continuously stirred by power. The mineral powder is rapidly dispersed in a uniform state, and can obtain an excellent dispersion state after leaving the gas distribution tower. At the same time, the high-pressure gas fed from the gas supply device is continuously depressurized layer by layer through the tower body of the gas distribution tower, and finally sprayed into the flash furnace in a horizontal direction at a low pressure, which prolongs the gas residence time in the reaction tower, and avoids the damage to the tower body that may be caused by the high-pressure gas directly impacting downward at high speed after entering the reaction tower. In addition, the airflow rushing directly downward will also cause the airflow to carry the mineral powder through the reaction tower space quickly, reducing the contact time between the reaction gas and the mineral powder, and reducing the smelting efficiency of the reaction tower space. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0021] Figure 1 A schematic diagram of the structure created by the present invention;

[0022] Figure 2 A schematic diagram of the gas distribution process is created for the present invention;

[0023] Figure 3 The present invention is a schematic diagram when applied to flash metallurgical equipment.

[0024] Description of reference numerals:

[0025] 1-gas distribution tower; 2-feeding nozzle; 3-connecting rod; 4-burner; 5-tower body; 6-gap. DETAILED DESCRIPTION

[0026] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0027] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0028] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood according to specific circumstances.

[0029] The present invention is described in detail below in conjunction with embodiments.

[0030] A flash furnace gas distribution system, such as Figures 1 to 3 As shown, it includes a gas distribution tower 1 connected to the outlet of the flash furnace gas supply device, and the tower body 5 is located in the flash furnace reaction tower. The gas distribution tower is a multi-layer structure, and the inner diameter of each layer of the tower body 5 gradually decreases from top to bottom, and a gap 6 is left between two adjacent tower bodies at the connection part.

[0031] The gas supply device, the gas distribution tower and the smelting space are closely combined through the uppermost tower body of the gas distribution tower, and the uppermost tower body of the gas distribution tower is connected to the top device of the smelting space. The vertical section of each tower body is roughly triangular. The cross section of each tower body is circular.

[0032] In an optional embodiment, if Figure 1 As shown, the tower body is divided into 6 layers, the diameter of which gradually decreases, and each layer is connected by a connecting rod 3, and the number of connecting rods between each two layers of the tower body is 3-12. Depending on the working environment, the number of connecting rods between different layers of the gas distribution tower can be different.

[0033] The connecting rod has the largest cross section on the side facing the center of the gas distribution tower, and its cross section gradually shrinks to a linear shape toward the outside of the gas distribution tower. That is, the connecting rod adopts a streamlined design that can effectively reduce resistance.

[0034] The tower structure of the gas distribution tower is as follows: Figure 2 As shown, the upper edge of each layer of the tower structure close to the center is marked as A, the lower edge is marked as B, and the outermost edge away from the center is marked as C. For example, the inner wall surface of the first layer of the tower body is marked as A2B2, the upper surface is marked as A2C2, and the height of the gap between the first layer of the tower body and the second layer of the tower body is marked as B2A3. It should be pointed out that, in fact, the uppermost layer of the gas distribution tower is connected to the gas supply device, so the upper and lower edges of the inner side of the gas supply device are marked as points A1 and B1. Therefore, the structure of the gas distribution tower is marked with "2" starting from the first layer of the tower body. It should be pointed out that, in a sense, the part of the gas supply device extending into the reaction tower can also be regarded as the first layer of the gas distribution tower.

[0035] When the high-temperature, high-pressure gas of the gas supply device flows from top to bottom between the first tower body and the second tower body of the gas distribution tower, since the inner diameter of the second tower body is smaller than that of the first tower body, the outer layer of the gas flowing from the first tower body to the second tower body will be guided out of the gas distribution tower by the surface formed by A2C2 and enter the smelting space. By analogy, when reaching the appropriate level, the high-temperature, high-pressure gas ejected from the gas supply device is divided into a fluid structure that is approximately "piece by piece" (i.e., thin gas flow layers layer by layer), and cuts into the smelting space of the reaction tower in a manner of uniformly spraying all around.

[0036] Specific parameter design adjustments may include:

[0037] Change A1B1, A2B2…A n B n The length of the airflow can change the frequency of stirring the mineral powder;

[0038] Change B1A2, B2A3…B n-1 The distance of An can change the initial velocity of the gas entering the smelting space;

[0039] By changing the inner diameter of each tower, the amount of gas ejected per unit time in each layer gap can be changed;

[0040] Changing the number of tower layers can change the time for providing continuous power for gas-solid mixing;

[0041] The gas-solid mixing effect is extremely sensitive to changes in the size and shape of the gas distribution tower. For example, changing the shape of the A2C2 line can change the angle at which the airflow cuts into the mineral powder.

[0042] In an optional embodiment, A1B1, A2B2...A n B n and A2C2, A3C3…A n C n By making the surface of the mixer into a spiral guide surface, an air flow with a rotating jet can be obtained, thereby providing better "stirring" power for the mineral powder.

[0043] The pressure of the gas ejected by the air supply device can be adjusted within a certain range, from 0.2kg / cm 2 Up to 50kg / cm 2 Therefore, there are many options when designing the gas distribution tower, with few limitations.

[0044] The following provides a method for gas distribution smelting using the above-mentioned flash furnace gas distribution system.

[0045] 1) Several feeding nozzles 2 and burners 4 are arranged outside the installation position of the gas supply device at the top of the flash furnace reaction tower, such as Figure 3 shown.

[0046] 2) High-temperature, high-pressure gas enters the gas distribution tower through the gas supply device, and then sprays out from the gaps in the multi-layer tower body of the gas distribution tower. The high-temperature, high-pressure gas is divided into a fluid structure that is approximately "layer by layer" and cuts into the flash furnace smelting space in a manner that is evenly sprayed all around.

[0047] 3) Add mineral powder to the flash furnace reaction tower through the feeding device. During the process of the mineral powder falling, it is impacted by the airflow sprayed from the gas distribution tower for many times, and is constantly "stirred" by the power, so that the mineral powder is quickly dispersed, and finally an excellent dispersion effect is achieved. Therefore, the mineral powder can contact the reaction airflow sprayed from the gas distribution system with a large specific surface area, and a chemical reaction will occur quickly.

[0048] 4) Fuel and oxygen-containing gas are sprayed into the burner and burned fully to supplement the heat required for smelting in the flash furnace reaction tower space and maintain the high temperature environment required for the chemical reaction in the space.

[0049] In an optional embodiment, the above-mentioned feeding device is arranged as a feeding nozzle 2 in a ring-shaped feeding manner. The feeding device can be a circular ring structure arranged concentrically with the gas supply device, located outside the gas supply device, and installed on the top of the flash furnace reaction tower. Multiple point feeding nozzles can also be arranged in a ring.

[0050] In an optional embodiment, point burners are arranged in a ring shape on the periphery of the above-mentioned feeding device to supplement the heat required by the flash furnace reaction tower space and maintain the high temperature environment required for the chemical reaction in the space. Usually, an annular point burner is arranged correspondingly on the periphery of the annular feeding nozzle or the annular point feeding nozzle. In fact, it is not necessary to strictly require that the burner and the feeding nozzle completely correspond to each other. In the process of powder dispersion and falling, it will be dispersed in the reaction tower space. The burner only needs to be able to fully heat the powder.

[0051] The materials for making the gas distribution tower and the annular nozzle can be mature materials already available on the market, such as a composite material of silicon carbide fiber and silicon carbide. This material can work directly at high temperatures without any auxiliary measures. If the refrigerant is passed through the center of the device, the range of material selection is wider. As for the refrigerant, it can be added through the gas supply device connected to the gas distribution tower and passed to the 1st, 2nd, 3rd...nth layer of the tower body through the connecting rod.

[0052] In an optional embodiment, the process of gas distribution smelting using the gas distribution tower created by the present invention is as follows:

[0053] The mineral powder sprayed from the ring-shaped feeding nozzles is cut into by the gas ejected from between the first and second layers of the gas distribution tower. At this time, the mineral powder falling into the space is in a state of lowest dispersion. Impacted by the high-speed airflow, the mineral powder will rapidly increase its dispersion. The energy of each layer of gas can be reasonably designed so that the mineral powder impacted by it will not touch the furnace wall.

[0054] When the mineral powder is impacted by the airflow for the first time, part of the mineral powder begins to disperse, and then it is impacted for the second time, and the mineral powder obtains a greater dispersion. In the process of continuous descent, it is constantly "stirred" by the power, so that the mineral powder quickly disperses toward a uniform state, and after leaving the gas distribution tower, it obtains an excellent dispersion state. As a result, the mineral powder contacts the reaction gas with a large specific surface area, and a chemical reaction occurs quickly.

[0055] It should be noted that the angle of gas cutting into the mineral powder, the gas volume, and the spacing of each layer of gas can all be designed and adjusted in advance, which makes the degree of gas-solid mixing controllable and is conducive to obtaining a good gas-solid mixing effect.

[0056] The invention has a reasonable structural design. The mineral powder dispersed and dropped from the feeding device will be impacted multiple times by the airflow blown out from the gaps between the tower bodies of each layer of the gas distribution tower, and is continuously stirred by power. The mineral powder is quickly dispersed in a uniform state, and can obtain an excellent dispersion state after leaving the gas distribution tower.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A flash furnace gas distribution system, characterized in that: It includes a gas distribution tower connected to the outlet of the flash furnace gas supply device, the uppermost layer of the gas distribution tower is connected to the gas supply device, the tower body is located in the flash furnace reaction tower, the gas distribution tower is a multi-layer structure, the inner diameter of each layer of the tower body gradually decreases from top to bottom, and a gap is left at the connection between two adjacent tower bodies; the vertical section of each layer of the tower body is roughly triangular; the cross section of each layer of the tower body is circular; every two layers of the tower body are fixed by 3-12 connecting rods; The side of the connecting rod facing the center of the gas distribution tower has the largest cross section, and its cross section gradually shrinks to a linear shape toward the outside of the gas distribution tower; The working range of the gas pressure sprayed by the air supply device is 0.2kg / cm 2 Up to 50kg / cm 2 .

2. A method for gas distribution smelting using the flash furnace gas distribution system according to claim 1, characterized in that: 1) Several feeding devices and burners are arranged near the gas supply device installed at the top of the reaction tower; 2) The high-pressure gas fed from the gas supply device enters the gas distribution tower, and the gas is ejected from the gap at the connection part of the multi-layer tower body of the gas distribution tower and cuts into the smelting space of the flash furnace reaction tower; 3) When adding materials, the mineral powder is impacted by the airflow sprayed from the gas distribution tower many times during its descent, and is quickly dispersed, so that the mineral powder can contact the reaction airflow sprayed from the gas distribution system with a larger specific surface area; 4) Fuel and oxygen-containing gas are sprayed into the burner and burned fully to supplement the heat required for smelting in the flash furnace reaction tower space.

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