阅读说明：本技术 一种冶金用机械搅拌喷吹脱硫搅拌器 (Metallurgical mechanical stirring, blowing and desulfurizing stirrer ) 是由 周遵传 唐萍 何鹏 张彦恒 梁新腾 和秀山 付灈 文光华 于 2021-10-28 设计创作，主要内容包括：本发明涉及一种冶金用机械搅拌喷吹脱硫搅拌器,包括搅拌轴和连接在搅拌轴下面的搅拌头；在搅拌头的外侧,沿周向设置有多个搅拌叶片,相邻搅拌叶片之间的夹角相同；在搅拌轴上设置有直通吹气通道,在部分或全部搅拌叶片内设置有斜向下的分流管道,每个分流管道与直通吹气通道连通,形成喷吹气体通道；每个分流管道的末尾形成喷吹口。本发明将脱硫剂喷吹孔设置在对称搅拌桨叶的最外沿壁面,气泡产生位置与中心漩涡区域有一定的距离,可以减少脱硫剂气泡聚集,降低气泡长大的概率,以增大气液反应面积,延长气液反应时间,增加脱硫反应的效率。(The invention relates to a mechanical stirring, blowing and desulfurizing stirrer for metallurgy, which comprises a stirring shaft and a stirring head connected below the stirring shaft; a plurality of stirring blades are arranged on the outer side of the stirring head along the circumferential direction, and included angles between adjacent stirring blades are the same; a through blowing channel is arranged on the stirring shaft, partial or all stirring blades are internally provided with downward inclined shunt pipelines, and each shunt pipeline is communicated with the through blowing channel to form a blowing gas channel; the end of each branch pipe forms a blowing opening. According to the invention, the desulfurizer blowing holes are arranged on the outermost wall surfaces of the symmetrical stirring blades, and the bubble generating positions are at a certain distance from the central vortex region, so that the accumulation of bubbles of the desulfurizer can be reduced, the probability of the growth of the bubbles can be reduced, the gas-liquid reaction area can be increased, the gas-liquid reaction time can be prolonged, and the desulfurization reaction efficiency can be increased.)

1. A mechanical stirring, blowing and desulfurizing stirrer for metallurgy comprises a stirring shaft (1) and a stirring head (2) connected below the stirring shaft (1); the method is characterized in that: a plurality of stirring blades (21) are arranged on the outer side of the stirring head (2) along the circumferential direction, and included angles between adjacent stirring blades (21) are the same; a straight-through blowing channel (3) is arranged on the stirring shaft (1), partial or all stirring blades (21) are internally provided with downward inclined shunt pipelines (4), and each shunt pipeline (4) is communicated with the straight-through blowing channel (3) to form a blowing gas channel; the end of each branch pipe (4) forms a blowing opening (5).

2. The metallurgical mechanical stirring, blowing and desulfurizing stirrer according to claim 1, wherein: the stirring blades (21) are 4, and the included angle between the stirring blades is 90 degrees.

3. The mechanical stirring, blowing and desulfurizing stirrer for metallurgy according to claim 2, wherein the number of the flow dividing pipes (4) is two, and the two flow dividing pipes are respectively connected with the lower end of the straight-through blowing channel (3) to form an inverted Y-shaped structure.

4. A metallurgical mechanical agitation blowing desulfurization agitator according to any one of claims 1 to 3, wherein the angle α of the divided flow pipe (4) with the horizontal direction is in the range of 10 to 45 °.

5. The mechanically stirring blowing desulfurization agitator for metallurgy according to any one of claims 1 to 3, wherein the blowing ports (5) are located near the lower end at a position lower than a half of the height of the stirring blades (21).

6. The metallurgical mechanical agitation blowing desulfurization agitator of claim 5, wherein the blowing ports (5) are located on the outermost side of the vertical surfaces of the corresponding agitating blades (21).

7. The mechanical stirring, blowing and desulfurizing stirrer for metallurgy according to claim 3, wherein two stirring blades of the diversion pipeline (4) are arranged and symmetrically arranged relative to the central line of the stirring shaft (1); the other two stirring blades without the shunt pipeline (4) are symmetrically arranged relative to the central line of the stirring shaft (1), and the distance between the stirring blades and the central line is less than that between the stirring blades with the shunt pipeline (4) and the central line.

8. The mechanical stirring blowing desulfurization stirrer for metallurgy according to claim 7, wherein the width of the stirring blade (21) in which the blowing holes (5) are located is smaller than the width of the stirring blade in which the branch pipes (4) are not provided.

9. The metallurgical mechanical agitation blowing desulfurization agitator according to any one of claims 1 to 3, wherein the stirring blade (21) is inserted to a depth greater than the liquid level in 3/4 of the molten bath.

Technical Field

The invention relates to the technical field of steel smelting processes, in particular to a mechanical stirring, blowing and desulfurizing stirrer for metallurgy, and particularly relates to a stirring paddle for magnesium-based stirring and combined blowing molten iron desulfurization.

Background

Sulfur is disadvantageous to the quality of steel in most cases, causes a problem of "hot shortness", and thus a desulfurization process must be performed, and since desulfurization of molten iron has a thermodynamic advantage of desulfurization, a desulfurization task for steel production is mostly located in a molten iron pretreatment step in a modern steel production flow. The hot metal pretreatment desulfurization mainly comprises a KR method and a blowing method, wherein the KR method is stirred to form a vortex to substitute a desulfurizing agent into hot metal for reaction, but has the problems of large iron loss and high temperature drop; the blowing method uses the compound blowing of lime and magnesium as the main stream, magnesium steam bubbles generated by the vaporization of metal magnesium in a desulfurizer in high-temperature molten iron are easy to gather and float upwards to be removed, the utilization rate of magnesium is low, and weak flow zones (flow velocity) with low flow velocity and desulfurizing agent which can not reach the bottom and the edge of a reactor molten pool are present at the bottom and the edge of the reactor molten pool due to the lack of circumferential flow<0.01m/s, gas volume fraction of magnesium vapor<10^-6) Thereby affecting deep desulfurization (molten iron [ S ]]<0.005%) of the composition. Some scholars propose a new idea for the problems: mechanical stirring and blowing are combined. The stirring paddle is used for increasing the circulation of the molten pool, reducing the dead zone of the molten pool, simultaneously crushing bubbles, realizing the dispersion and the refinement of the bubbles, increasing the desulfurization reaction area and the reaction time, and avoiding the overlarge temperature drop because the magnesium desulfurization is an exothermic reactionThe stirring and blowing mode solves the problems of low utilization rate, unstable deep desulfurization, high temperature drop and the like. At present, the stirring and blowing method is to place the air blowing holes below the stirring paddles, and the air bubbles are broken and thrown out by the stirring paddles in the floating process, for example, the blowing type spiral stirring paddle for molten iron desulphurization disclosed in application No. CN201911052470.1 and the rotary blowing composite molten iron desulphurization stirrer disclosed in application No. 201821570143.6 adopt the method, but the physical water simulation experiment of mechanical stirring and blowing by Liu Yan and other people shows that in a one-way stirring mode, no matter one-hole vertical blowing, L-shaped horizontal blowing or four-hole horizontal blowing, the air bubbles can be quickly gathered at a central vortex, the dispersion and refinement degree of the air bubbles is reduced, and the method shows that after the desulfurizer blown out from the stirring and blowing method blows out the air bubbles at the bottom, the air bubbles can be attracted to the central vortex formed by stirring, so that a large amount of air bubbles can not be broken and thrown out, but collide with each other and grow up, and quickly lift away from a molten pool, so that the contact area and the reaction time of the gas-liquid desulfurization reaction are both in a lower level. Therefore, in order to further improve the desulfurization efficiency, reduce the cost, solve the above-mentioned problem of the accumulation and growth of bubbles and reduce the weak flow region (flow velocity)<0.01m/s, gas volume fraction of magnesium vapor<10^-6) It is necessary to develop a new stirring blowing desulfurization apparatus.

Disclosure of Invention

In view of the defects in the prior art, the invention aims to provide a mechanical stirring, blowing and desulfurizing stirrer for metallurgy. The stirrer reduces the accumulation and growth of bubbles by dispersed blowing away from the central vortex; the rising time of bubbles can be prolonged, and the probability of channel blockage is reduced; and the reaction time can be prolonged, and the strength of desulfurization gas-liquid reaction can be improved.

In order to solve the technical problem, the invention adopts the following technical scheme:

a mechanical stirring, blowing and desulfurizing stirrer for metallurgy comprises a stirring shaft and a stirring head connected below the stirring shaft; the method is characterized in that: a plurality of stirring blades are arranged on the outer side of the stirring head along the circumferential direction, and included angles between adjacent stirring blades are the same; a through blowing channel is arranged on the stirring shaft, partial or all stirring blades are internally provided with downward inclined shunt pipelines, and each shunt pipeline is communicated with the through blowing channel to form a blowing gas channel; the end of each branch pipe forms a blowing opening.

According to the structure, the desulfurizer blowing holes are formed in the outermost wall surfaces of the symmetrical stirring blades, and the bubble generating positions are at a certain distance from the central vortex region, so that the accumulation of bubbles of the desulfurizer can be reduced, the probability of the growth of the bubbles can be reduced, the gas-liquid reaction area can be increased, the gas-liquid reaction time can be prolonged, and the desulfurization reaction efficiency can be increased.

Further: the stirring blades are 4, and the included angle between the stirring blades is 90 degrees. Stirring vane evenly sets up in the circumferencial direction, rotates steadily, improves stirring efficiency.

Furthermore, the number of the flow dividing pipelines 4 is two, and the two flow dividing pipelines are respectively connected with the lower end of the straight-through air blowing channel to form an inverted Y-shaped structure. The blowing channel of the Y-shaped structure is designed to be in the downward inclined direction, so that the blockage problem of T-shaped blowing can be reduced, and the bubbles of the desulfurizing agent can have downward initial speed.

Further, the angle α of the branch ducts 4 with the horizontal is in the range of 10-45 °. The downward-inclined blowing channel can further increase the rising time of bubbles, prolong the gas-liquid reaction time and increase the efficiency of desulfurization reaction.

Further, the position of the blowing opening is close to the lower end and is lower than the position of half of the height of the stirring blade. The downward-inclined blowing channel can further increase the rising time of bubbles, prolong the gas-liquid reaction time and increase the efficiency of desulfurization reaction.

Further, the blowing ports are located on the outermost side of the vertical face of the corresponding stirring blade. The blowing opening is arranged at the farthest end of the stirrer and is located at the position of the maximum diameter of the stirring, the position where bubbles are generated has a certain distance with the central vortex area, and the action area of the bubbles is larger.

Furthermore, two stirring blades of the shunting pipeline are arranged and are symmetrically arranged relative to the central line of the stirring shaft; the other two stirring blades without the shunt pipelines are symmetrically arranged relative to the central line of the stirring shaft, and the distance between the stirring blades and the central line is less than that between the stirring blades with the shunt pipelines and the central line. Like this, the agitator forms the structure of two long limits, two minor faces, and the molten steel is stirred more easily on long limit when the stirring, and the regional great vortex that forms more easily between rotation in-process long limit and the minor face, stirring effect is more excellent.

Furthermore, the width of the stirring blade where the blowing hole is located is smaller than the width of the stirring blade without the shunt pipeline. Therefore, the device is more favorable for forming larger vortex in the area between the long edge and the short edge in the rotating process, has better stirring effect, is also more favorable for dispersing and uniformly diffusing gas containing the desulfurizer entering the molten pool from the downward inclination of the blowing hole, increases the gas-liquid reaction area, prolongs the gas-liquid reaction time, and increases the efficiency of desulfurization reaction.

Further, the depth of insertion of the stirring blade is greater than the liquid level in the 3/4 molten bath.

Compared with the prior art, the blowing desulfurization stirrer provided by the invention has the following beneficial effects:

1. according to the invention, the desulfurizer blowing holes are arranged on the outermost wall surfaces of the symmetrical stirring blades, and the bubble generating positions are at a certain distance from the central vortex region, so that the accumulation of bubbles of the desulfurizer can be reduced, the probability of the growth of the bubbles can be reduced, the gas-liquid reaction area can be increased, the gas-liquid reaction time can be prolonged, and the desulfurization reaction efficiency can be increased.

2. The invention designs the blowing channel in the stirring paddle to be in the downward inclined direction, which can not only reduce the blockage problem of large resistance at the 90-degree included angle of T-shaped blowing, but also ensure that the bubbles of the desulfurizer have downward initial speed, increase the rising path of the bubbles, further increase the rising time of the bubbles and prolong the gas-liquid reaction time, simultaneously the downward speed also brings the desulfurizer into the bottom of the reactor molten pool, reduces the weak reaction zone at the lower part of the blowing hole, and increases the efficiency of desulfurization reaction and the stability of desulfurization.

3. The distance between the two symmetrical edges where the desulfurizer blowing holes are located and the center line is larger than that between the other two symmetrical edges and the center line, so that the distance between the magnesium bubble generating position formed by the desulfurizer blown out of the blowing holes and the central vortex area is farther under the condition of certain stirring power, the accumulation of desulfurizer bubbles can be reduced, the probability of bubble growth is reduced, and the gas-liquid reaction area is increased; and two long sides where the blowing holes are located and the other two short sides form a structure, so that molten steel is stirred more easily during stirring, a vortex is formed, and the stirring effect is better. And the gas containing the desulfurizer can be dispersed and uniformly diffused, the gas-liquid reaction area is enlarged, the gas-liquid reaction time is prolonged, and the desulfurization reaction efficiency is increased.

Drawings

FIG. 1 is a schematic structural diagram of a mechanical stirring, blowing and desulfurizing stirrer for metallurgy;

fig. 2 is a schematic structural diagram of a second embodiment of the present invention.

Wherein: 1-stirring shaft, 2-stirring head, 3-straight-through blowing channel, 4-diversion pipeline, 5-blowing opening and 21-stirring blade.

Detailed Description

The technical solution in the embodiment of the present invention is clearly and completely described below with reference to the embodiment of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, the novel stirring, blowing and desulfurizing stirrer provided by the embodiment of the invention comprises a stirring shaft 1 and a stirring head 2, wherein the stirring shaft 1 is generally vertically arranged, and the stirring head 2 is connected below the stirring shaft 1 to form a fastening structure; a plurality of stirring blades 21 are arranged on the outer side of the stirring head 2 along the circumferential direction, and the stirring blades 21 protrude outwards along the radial direction; the number of the stirring vanes 21 is usually 3, 4, 6, 8, etc. pieces, and they are arranged in the circumferential direction, i.e., the included angles between the adjacent stirring vanes 21 are the same. Shown in the figure are 4 stirring blades 21, arranged vertically at an angle of 90 to each other.

A through blowing channel 3 is arranged on the stirring shaft 1, partial or all stirring blades 21 are internally provided with downward inclined shunt pipelines 4, and each shunt pipeline 4 is communicated with the through blowing channel 3 to form a blowing gas channel; the end of each branch pipe 4 forms a blowing opening 5, and gas enters from an opening at the upper end of the straight blowing channel 3 and is blown out of the blowing opening 5 through each branch pipe 4. The blowing openings 5 are located on the vertical surfaces of the corresponding agitating blades 21, the outermost surfaces of the vertical surfaces.

As shown in fig. 1, two diversion pipelines 4 are respectively connected with the lower end of the straight-through blowing channel 3 to form an inverted Y-shaped structure. The diversion pipeline 4 is obliquely arranged downwards, and the included angle alpha between the diversion pipeline 4 and the horizontal direction is 10-45 degrees, so that gas containing a desulfurizer is obliquely downwards inclined to enter a molten pool. The position of the blowing openings 5 is near the lower end, typically a position lower than half the height of the stirring vanes 21.

As shown in fig. 1, two stirring blades 21 of the diversion pipeline 4 are arranged, and are symmetrically arranged relative to the central line of the stirring shaft 1; the other two stirring blades are not provided with the shunt pipes 4, the two stirring blades are symmetrically arranged relative to the central line of the stirring shaft 1, and the distance between the two stirring blades and the central line is smaller than that between the other two stirring blades provided with the shunt pipes 4 and the central line; two limits at blowing hole 5 place are long limits, be greater than two other limits that do not set up blowing hole 5 with the distance of central line, form two long limits, the structure of two minor faces, the molten steel is stirred more easily on long limit when the stirring, the regional great vortex that forms more easily between rotation in-process long limit and minor face, stirring effect is more excellent, be favorable to more from the gas dispersion that contains the desulfurizer that 5 downward slopping in blowing hole got into the molten bath, the even diffusion, increase gas-liquid reaction area, prolong gas-liquid reaction time, increase desulfurization reaction's efficiency. In addition, the length of the two stirring blades 21 provided with the shunt pipelines 4 is longer, so that the blowing holes 5 are further far away from the central vortex, and the dispersion and the fineness of bubbles are improved. Through analytical research and experimental verification, the applicant finds that the width of the stirring blade 21 (long side) where the blowing hole 5 is located is smaller than the width of the stirring blade (short side) without the shunt pipeline 4, so that the larger vortex can be formed in the area between the long side and the short side in the rotating process, the stirring effect is better, the gas containing the desulfurizer entering the molten pool from the blowing hole 5 in a downward tilting mode can be dispersed and uniformly diffused, the gas-liquid reaction area is increased, the gas-liquid reaction time is prolonged, and the desulfurization reaction efficiency is increased.

As shown in fig. 2, which is a second embodiment structure of the present invention, the number of the stirring vanes 21 shown in the figure is three, and the three stirring vanes are circumferentially arranged and form an included angle of 120 ° with each other; the branch ducts 4 are provided in all three stirring vanes 21. Other structural parts that are the same as those in embodiment 1 will not be described in detail.

During the concrete stirring operation, the insertion depth of the stirring blade 21 is recommended to be larger than the liquid level height in the molten pool of 3/4, the stirring shaft 1 is internally provided with a straight-through blowing pipeline 3, the tail end of the straight-through blowing pipeline is provided with an inverted Y-shaped shunt pipeline 4, the desulfurizing agent and the carrier gas are blown out from an outlet 5 through a blowing gas channel in the stirrer and enter the molten pool, and the outlet 5 of the blowing channel is necessarily positioned on the vertical wall surface on the outermost edge.

The novel 4-blade two-hole blowing stirrer is compared with a common stirrer with a blowing position located at the lower end of the stirring blade and subjected to T-shaped blowing to use CO₂The reaction of NaOH simulates the experimental research of carrying out physical simulation on the desulfurization reaction, and in the experiment, in order to make the bubble dwell time longer, the insertion depth of the stirring paddle is greater than that of the ordinary KR stirring mode, and this time is 0.8 times of the depth of the molten pool, and in order to guarantee the rotating speed of the stirring paddle, the diameter of the stirring paddle is 0.21 times of the diameter of the molten iron tank. The results are the average of three experiments and are shown in table 1. As can be seen from the gas content and the maximum size of the bubbles, the fineness and the dispersion degree of the bubbles are obviously improved, and the numerical values of the volume mass transfer coefficient and the gas utilization rate intuitively reflect that the novel stirring and blowing paddle can effectively improve the efficiency of gas-liquid reaction.

TABLE 1 CO₂-NaOH reaction simulation desulfurization experimental result

	Rotating speed (r/min)	Gas content (%)	Maximum size (cm) of the bubble	Volumetric mass transfer coefficient (10)-4s-1）	Gas utilization (%)
						Ordinary stirring blowing paddle	90	19.57	2.32	2.954	41
Novel stirring and blowing paddle	90	22.93	1.61	4.411	62

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the technical solutions, and although the present invention has been described in detail by referring to the preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of the present invention can be made without departing from the spirit and scope of the technical solutions, and all the modifications and equivalent substitutions should be covered by the claims of the present invention.