A nozzle for gas-particle two-phase suspension metallurgical process

Abstract

The present invention provides a nozzle for a gas-particle two-phase suspension metallurgical process, wherein the concentrate is first mixed with swirl wind to produce a premixing effect, and the concentrate particles are dispersed more evenly under the action of the swirl wind. The dispersion of the premixed concentrate and swirl wind is further enhanced by the flow-guiding effect of the guide cone surface. The distributed wind coming out of the dispersed flow channel outlet of the dispersed surface further disperses the concentrate moving there, and the degree of mixing with the peripheral process wind is more sufficient and uniform, thereby improving the concentrate combustion effect, strengthening the mass transfer and heat transfer rates in the reaction tower, helping to improve the equipment capacity, and effectively reducing the smoke dust occurrence rate and the SO3 generation rate in the flue gas.

Description

Technical Field

[0001] The invention relates to the technical field of copper smelting and lead smelting, and in particular to a nozzle used in a gas-particle two-phase suspension metallurgical process. Background Art

[0002] The flash furnace is an enhanced smelting equipment invented by Outokumpu in Finland for processing powdered sulfide minerals. It is generally composed of four main parts: concentrate nozzle, reaction tower, sedimentation tank, and ascending flue. In the flash smelting process of copper, the concentrate nozzle is its core component, located at the top of the reaction tower. Copper concentrate and process air and dispersed air are sprayed into the reaction tower through the concentrate nozzle. After the concentrate is mixed with the reaction gas, a combustion reaction occurs, and oxidization forms slag and matte, and a large amount of heat is released. Therefore, the uniformity of the mixture of concentrate and reaction gas plays a decisive role in the oxidation reaction of the concentrate. If the mixture is not good, there may be a phenomenon of delayed ignition, which affects the mass transfer and heat transfer rate of the entire combustion reaction, and even some unreacted materials fall directly into the sedimentation tank, forming a "raw material" phenomenon, causing the reaction tower furnace condition to deteriorate, the content of ferroferric oxide in the slag to increase, and copper and slag discharge to be difficult. At the same time, the occurrence rate of smoke dust increases, the generation rate of SO3 in the flue gas increases, and the utilization efficiency of oxygen decreases significantly.

[0003] At present, most of the concentrate nozzles used in flash smelting in my country's smelters are central injection diffusion concentrate nozzles, which are equipped with air regulating cones, material distribution cones, dispersed air and central oil guns. By moving the upper and lower positions of the air regulating cone, the process air outlet speed is steadily and steplessly adjusted to mix the concentrate with oxygen-enriched air in the reaction tower. However, with the continuous increase in the production capacity of the reaction tower and the continuous increase in the smelting intensity, the incidence of abnormal conditions such as raw materials in the middle and lower production, material segregation, furnace overheating and increased smoke rate has increased significantly. The existing concentrate nozzle structure can no longer meet the needs of sufficient mixing and rapid reaction of gas and materials in the furnace under high feed conditions.

[0004] Patent CN200880105946.7 discloses a concentrate nozzle. On the basis of the existing concentrate nozzle, a guide vane is arranged in the air chamber to provide a corresponding rotating wind flow field. The manufacturing process of the concentrate nozzle arranged in this way is complicated, and after the arrangement, the intensity of the rotating wind flow field of the reaction gas is reduced and weakened when it passes through the bird's nest water jacket and reaches the top of the flash furnace, which fails to meet the expected requirements. The concentrate nozzle still has the problems of uneven material mixing, upward reflux of airflow, and poor concentrate discharge, and the effect is not good.

[0005] Patent CN201410725685.6 discloses a cyclone concentrate nozzle. On the basis of the existing concentrate nozzle, a cyclone bird's nest water jacket capable of generating a rotating wind is fixed on the lower end of the air chamber, and a cyclone tube capable of generating a rotating wind is fixed on the lower end of the feed pipe and the outer layer of the feed pipe. The rotating wind generated by the cyclone bird's nest water jacket and the cyclone tube has the same wind direction. The nozzle manufacturing process is complicated, and the mixing effect of the gas rotating into the furnace and the concentrate is not significantly enhanced. The intensity of the rotating wind flow field when entering the reaction tower does not meet the expected requirements. The concentrate nozzle still has uneven material mixing and no significant effect.

[0006] Patents CN201020284998.X and CN201110208013.4 disclose two methods, both of which place the concentrate completely on the outer ring of the reaction air cyclone, rely on the cyclone expansion to drive the concentrate particles to form a high-speed rotating mixed cyclone and complete the mass transfer and heat transfer between the gas and particles. However, since the cyclone intensity of the reaction air depends on the amount of concentrate loaded in the equipment, when the production capacity is small, the reaction air cyclone intensity is too small to drive the particles to rotate, and when the reaction gas flow is too large, it is easy to cause erosion to the reaction tower wall.

[0007] Patent CN201510078260.5 discloses a flotation smelting method, in which powdered sulfide concentrate and oxygen-containing gas are sprayed into the space of a high-temperature reaction tower through equipment. The oxygen-containing gas is divided into two parts before entering the equipment: the second oxygen-containing gas is sprayed into the reaction tower in an annular direct current manner to form a bell-shaped wind curtain; the first oxygen-containing gas is converted into a rotating jet by the equipment and injected into the center of the wind curtain. In the annular space between the two airflows, the concentrate enters in a direction biased toward the center, is drawn into the rotating jet and sucks in the high-temperature flue gas from the bottom of the reaction tower to form a two-phase rotating jet of gas-particle mixing. When the sulfide concentrate is ignited by high temperature, it undergoes a violent combustion reaction with oxygen and releases flue gas rich in SO2, while forming a mixed melt containing matte (or metal) and slag. Finally, at the bottom of the reaction tower, the matte (or metal) and slag are separated to complete the metallurgical process. However, its adaptability to feeding is poor. When the feeding amount is large, the swirl air volume is large, the swirl intensity is high, the reaction effect is good, but the smoke dust generation rate is high. When the feeding amount is changed, especially when the feeding amount is small, the swirl air volume is small, which is not enough to drive the particles to rotate, the furnace condition deteriorates, and even raw material leakage occurs. Summary of the invention

[0008] The present invention aims to provide a nozzle for gas-particle two-phase suspension metallurgy process, so as to improve the gas-particle mass transfer and heat transfer rate in the suspension smelting process and solve the technical problems such as high smoke rate.

[0009] To achieve the above-mentioned purpose, the present invention provides a nozzle for a gas-particle suspension smelting process, which includes, from the inside to the outside, a vertical, sleeve-arranged oxygen supply pipe, a swirl air pipe and a feed pipe, and correspondingly, a central oxygen channel, a distribution wind channel, a swirl wind channel and a concentrate channel are formed, a concentrate channel outlet is provided at the bottom of the concentrate channel, a swirl blade is provided at the bottom of the swirl wind channel, the lowest end of the swirl blade is higher than the concentrate channel outlet, the distribution wind channel extends downward out of the concentrate channel outlet, and a guide cone with a dispersion flow channel is installed at the bottom, a dispersion surface is formed at the connection between the guide cone and the dispersion flow channel, the central oxygen channel is downward to the bottom of the guide cone, and a central oxygen outlet is provided, a water jacket is sleeved on the outside of the feed pipe, a process air chamber is formed between the feed pipe and the water jacket, a process air outlet is provided at the bottom of the process air chamber, and the process air outlet is higher than the concentrate channel outlet.

[0010] Preferably, the concentrate nozzle is arranged above the reaction tower.

[0011] Preferably, the center lines of the oxygen supply pipe, the swirl air pipe and the feed pipe overlap and are vertical, and the pipe diameters increase successively.

[0012] Preferably, a distribution air channel is formed in the oxygen supply pipe, a cyclone air channel is formed between the oxygen supply pipe and the cyclone air pipe, and a concentrate channel is formed between the cyclone air pipe and the feed pipe.

[0013] Preferably, a swirl air outlet is provided at the bottom of the swirl air channel, and at the position of the swirl air outlet, a swirl blade is fixed between the distribution air duct wall and the swirl air duct wall by threads, and the swirl blade can be vertically moved up and down or change the inclination angle through the threaded connection.

[0014] Preferably, a circle of dispersion channels is evenly and horizontally distributed below the dispersion surface, and the angle between the dispersion channels and the dispersion surface is 60°, in a rotational distribution.

[0015] Further preferably, the lower end of the guide cone is cylindrical, the dispersion flow channel is located at the center of the cylinder, and the distributed wind is radially emitted at an angle of 60° to the side wall.

[0016] Preferably, an adjusting cone that can move up and down is provided on the outside of the feed pipe, the middle area of ​​the adjusting cone is a cylindrical surface, and the upper and lower ends are gradually reduced to form a frustum-like shape. When the adjusting cone moves downward, the distance between its surface and the water jacket decreases, the process air outlet area decreases, and the process air flow rate increases. Conversely, when the adjusting cone moves upward, the process air speed decreases.

[0017] The above-mentioned working method of the nozzle used in the gas-particle suspension smelting process comprises the following specific steps:

[0018] (1) The concentrate entering the concentrate channel is mixed with the swirl air entering the swirl air channel in the concentrate channel to form an air-concentrate mixture, which continues to flow downward in a swirl state; at the same time, the distributed air entering the distributed air channel flows downward to the dispersed flow channel outlet, and the process air entering the process air chamber flows downward to the process air outlet;

[0019] (2) Under the dispersing effect of the dispersing surface, a part of the mixture continues to diffuse outward along the dispersing surface, and the other part of the mixture still enters the furnace in a swirling state. Under the dispersing effect of the distributed air in the same rotating direction ejected from the dispersing flow channel outlet, the mixture is fully and evenly mixed with the process air coming out of the process air outlet.

[0020] Preferably, in step (1), under the action of the swirl blades, the swirl wind flows to the swirl wind outlet to form a swirl, thereby driving the concentrate to form an air-concentrate mixture in a swirl state.

[0021] Further preferably, the swirl blades can be moved upward to increase the mixing space of the concentrate and the swirl wind.

[0022] Further preferably, the swirl blades can change the angle with the horizontal direction to change the swirl wind outlet angle, so that the swirl intensity changes accordingly with the feed amount, which can effectively improve the uniformity of mixing of concentrate and process air, and thus improve the combustion effect of the concentrate; under different feed amounts, the flow rate of the swirl wind adaptably changes.

[0023] Preferably, in step (1), the cross-sectional area of ​​the dispersion flow channel can be expanded by 1 time, and the number can be adjusted from 60 to 90, and can be adjusted from one row to two rows, so that the emitted distributed wind can better disperse the concentrate coming down from above, thereby enhancing the mixing degree of the concentrate and the process air, and further improving the combustion effect of the concentrate.

[0024] Preferably, in step (2), when the concentrate feed rate increases by 10 t / h, the position of the guide cone is moved down by 10 mm, so that the space for the mixture to enter the flash furnace through the dispersion surface is wider and the horizontal component of the exit velocity is larger.

[0025] Further preferably, the curvature radius R of the dispersion surface may be increased, with a maximum value not exceeding 1 / 2 of the cylindrical diameter D, so that the concentrate moving along the dispersion surface is better dispersed and mixed with the process air better.

[0026] The present invention has the following beneficial effects:

[0027] By using the concentrate nozzle of the present invention, the concentrate is first mixed with the swirl wind to produce a premixing effect, and the concentrate particles are dispersed more evenly under the action of the swirl wind. The dispersion of the premixed concentrate and the swirl wind is further enhanced through the guide effect of the guide cone surface. The swirl distribution wind that forms a swirl under the action of the dispersion flow channel makes the concentrate moving here further dispersed, strengthens the swirl intensity of the air-concentrate mixture, and thus the degree of mixing with the peripheral process wind is more sufficient and uniform. Through on-site industrial tests, at a concentrate feed rate of 140t / h, the combustion effect of the concentrate in the reaction tower is significantly improved, the mass transfer and heat transfer rates in the tower are improved, the content of Fe3O4 in the slag is reduced by 2%, the smoke dust generation rate is reduced to about 3%, the oxygen utilization rate is increased by about 1%, and the SO3 generation rate in the smoke dust is reduced by about 1%, which reduces the difficulty of subsequent smoke dust treatment.

[0028] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0030] Figure 1 It is a schematic diagram of the structure of the present invention;

[0031] Figure 2 It is a partial enlarged view of the swirl blade;

[0032] Figure 3 It is a schematic diagram of the structure of the guide cone;

[0033] Figure 4 This is a schematic diagram of the bottom structure of the guide cone

[0034] Among them, 1 is the central oxygen channel, 2 is the distribution air channel, 3 is the swirl air channel, 4 is the concentrate channel, 5 is the process air inlet, 6 is the water jacket, 7 is the swirl air duct wall, 8 is the regulating cone, 9 is the distribution air duct wall, 10 is the concentrate channel wall, 11 is the swirl blade, 12 is the process air outlet, 13 is the reaction tower, 14 is the swirl air outlet, 15 is the concentrate channel outlet, 16 is the dispersion surface, 17 is the dispersion flow channel outlet, 18 is the central oxygen outlet, 19 is the guide cone, and 20 is the dispersion flow channel. DETAILED DESCRIPTION

[0035] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, but the present invention can be implemented in many different ways as defined and covered by the claims.

[0036] like Figure 1 to Figure 3A nozzle for gas-particle suspension smelting process shown in the figure comprises, from the inside to the outside, a vertical, sleeve-arranged oxygen supply pipe, a swirl air pipe and a feed pipe, and correspondingly, a central oxygen channel 1, a distribution air channel 2, a swirl air channel 3 and a concentrate channel 4 are formed, a concentrate channel outlet 15 is provided at the bottom of the concentrate channel 4, a swirl blade 11 is provided at the bottom of the swirl air channel 3, and the lowest end of the swirl blade 11 is higher than the concentrate channel outlet 15, the distribution air channel 2 protrudes downward from the concentrate channel outlet 15, and a guide cone 19 with a dispersion flow channel 20 is installed at the bottom, and a dispersion surface 16 is formed at the connection between the guide cone 19 and the distribution air channel 1, a water jacket 6 is sleeved on the outside of the feed pipe, and a process air chamber is formed between the feed pipe and the water jacket 6, and a process air inlet 5 and a process air outlet 12 are respectively provided at the top and bottom of the process air chamber, and the process air outlet 12 is higher than the concentrate channel outlet 15.

[0037] The concentrate nozzle is arranged above the reaction tower 13 .

[0038] The center lines of the oxygen supply pipe, cyclone air pipe and feed pipe overlap and are vertical, and the pipe diameters increase successively. A central oxygen channel 1 is formed in the oxygen supply pipe, a distribution air channel 2 is formed between the oxygen supply pipes, a cyclone air channel 3 is formed between the oxygen supply pipe and the cyclone air pipe, and a concentrate channel 4 is formed between the cyclone air pipe and the feed pipe.

[0039] A swirl air outlet 14 is provided at the bottom of the swirl air channel 3. At the position of the swirl air outlet 14, a swirl blade 11 is fixed between the distribution air duct wall 9 and the swirl air duct wall 7 by threads. The swirl blade 11 can be vertically moved up and down or change the inclination angle through the threaded connection.

[0040] A circle of dispersion channel openings 17 is evenly and horizontally arranged below the dispersion surface 16. The dispersion channel 20 has an angle of 60° with the dispersion surface and is distributed in a rotational manner.

[0041] The lower end of the guide cone 19 is cylindrical, and the dispersion flow channel opening is located at the center of the cylinder. The distributed wind is ejected horizontally at an angle of 60° to the side wall.

[0042] The outer side of the feed pipe (i.e. the corresponding concentrate channel wall 10) is provided with an adjusting cone 8 that can move up and down. The middle area of ​​the adjusting cone is a cylindrical surface, and the upper and lower ends taper to form a frustum-like shape. When the adjusting cone 8 moves downward, the distance between its surface and the water jacket 6 decreases, the area of ​​the process air outlet 12 decreases, and the process air flow rate increases. Conversely, when the adjusting cone 8 moves upward, the process air speed decreases.

[0043] The above-mentioned working method of the nozzle used in the gas-particle suspension smelting process comprises the following specific steps:

[0044] (1) The concentrate entering the concentrate channel 4 is mixed with the swirl air entering the swirl air channel 3 in the concentrate channel 4 to form an air-concentrate mixture, which continues to flow downward in a swirl state; at the same time, the distributed air entering the distributed air channel 2 flows downward to the dispersed flow channel opening 17, and the process air entering the process air chamber flows downward to the process air outlet 12;

[0045] (2) Under the dispersing effect of the dispersing surface 16, a part of the mixture continues to diffuse outward along the dispersing surface, and the other part of the mixture still enters the furnace in a swirling state. Under the dispersing effect of the distributed air in the same rotating direction ejected from the dispersing flow channel 20, the mixture is fully and evenly mixed with the process air coming out of the process air outlet 12.

[0046] Preferably, in step (1), under the action of the swirl blades 11, the swirl wind reaches the swirl wind outlet 14 to form a swirl, thereby driving the concentrate to form an air-concentrate mixture in a swirl state.

[0047] The swirl blade 11 can move upward to increase the mixing space of the concentrate and the swirl wind. The swirl blade 11 can change the angle with the horizontal direction to change the swirl wind outlet 14 swirl wind exit angle, so that the swirl intensity changes accordingly with the feed amount, which can effectively improve the uniformity of the mixing of the concentrate and the process air, thereby improving the concentrate combustion effect; under different feed amounts, the flow rate of the swirl wind changes adaptably.

[0048] In step (1), the number of dispersion channels 20 can be adjusted so that the emitted distributed air can better disperse the concentrate coming down from above, thereby enhancing the mixing degree of the concentrate and the process air, and further improving the combustion effect of the concentrate.

[0049] In step (2), when the amount of concentrate is large, the position of the guide cone 19 can be appropriately moved downward to make the space for the mixture to enter the flash furnace through the dispersion surface wider and the horizontal component of the exit velocity larger. The radius of curvature of the dispersion surface can be increased, so that the concentrate moving along the dispersion surface 16 can be better dispersed and the mixing effect with the process air can be better.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A nozzle for a gas-particle suspension smelting process, characterized in that: From the inside to the outside, it includes a vertical, sleeve-arranged oxygen supply pipe, a swirl air pipe and a feed pipe, and correspondingly forms a central oxygen channel, a distribution air channel, a swirl air channel and a concentrate channel. The bottom of the concentrate channel is provided with a concentrate channel outlet, the bottom of the swirl air channel is provided with a swirl blade, the lowest end of the swirl blade is higher than the concentrate channel outlet, the distribution air channel extends downward out of the concentrate channel outlet, and a guide cone with a dispersion flow channel is installed at the bottom, and a dispersion surface is formed at the connection between the guide cone and the distribution air channel. The central oxygen channel extends downward to the bottom of the guide cone, and a central oxygen outlet is provided. A water jacket is sleeved on the outside of the feed pipe, and a process air chamber is formed between the feed pipe and the water jacket. The bottom of the process air chamber is provided with a process air outlet, and the process air outlet is higher than the concentrate channel outlet. A circle of dispersed flow channels is evenly and horizontally opened below the dispersed surface of the guide cone. The dispersed flow channels and the dispersed surface have an angle of 60°, and are distributed in a rotational manner.

2. A nozzle for gas-particle suspension smelting process according to claim 1, characterized in that: The nozzle is arranged above the reaction tower.

3. The nozzle for gas-particle suspension smelting process according to claim 1, characterized in that: The center lines of the oxygen supply pipe, the swirl air pipe and the feed pipe overlap and are arranged vertically, and the pipe diameters increase successively.

4. The nozzle for gas-particle suspension smelting process according to claim 1, characterized in that: A swirl air outlet is provided at the bottom of the swirl air channel. At the position of the swirl air outlet, a swirl blade is fixed between the distribution air duct wall and the swirl air duct wall by threads. The swirl blade can move vertically up and down or change the inclination angle through the threaded connection.

5. The nozzle for gas-particle suspension smelting process according to claim 1, characterized in that: An adjusting cone that can move up and down is provided on the outside of the feed pipe. The middle area of ​​the adjusting cone is a cylindrical surface, and the upper and lower ends gradually taper to form a frustum-like shape. When the adjusting cone moves downward, the distance between its surface and the water jacket decreases, the process air outlet area decreases, and the process air flow rate increases. Conversely, when the adjusting cone moves upward, the process air speed decreases.

6. The nozzle for gas-particle suspension smelting process according to claim 1, characterized in that: A distribution air channel is formed in the oxygen supply pipe, a cyclone air channel is formed between the oxygen supply pipe and the cyclone air pipe, and a concentrate channel is formed between the cyclone air pipe and the feed pipe.

7. A method for operating a nozzle for a gas-particle suspension smelting process according to any one of claims 1 to 6, characterized in that: The specific steps are as follows: (1) The concentrate entering the concentrate channel is mixed with the swirl air entering the swirl air channel in the concentrate channel to form an air-concentrate mixture, which continues to flow downward in a swirl state; at the same time, the distributed air entering the distributed air channel flows downward to the dispersion flow channel, and the process air entering the process air chamber flows downward to the process air outlet; (2) Under the dispersing effect of the dispersing surface, a part of the mixture continues to diffuse outward along the dispersing surface, while the other part of the mixture still enters the furnace in a swirling state. Under the dispersing effect of the distributed air in the same rotating direction ejected from the dispersing flow channel outlet, the mixture is fully and evenly mixed with the process air coming out of the process air outlet.

8. The working method according to claim 7, characterized in that: In step (1), under the action of the swirl blades, the swirl wind flows to the swirl wind outlet to form a swirl, thereby driving the concentrate to form an air-concentrate mixture in a swirl state.

9. The working method according to claim 8, characterized in that: In step (2), under the action of the dispersion flow channel, the distributed wind forms a vortex at the outlet of the dispersion flow channel, so that the concentrate in the mixture is further dispersed and the vortex intensity of the mixture is enhanced.

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