Efficient desulfurization method and system for sulfur-containing molten iron

Abstract

The invention relates to the technical field of molten iron pretreatment, in particular to an efficient desulfurization method and system for sulfur-containing molten iron. The efficient desulfurization method for the sulfur-containing molten iron comprises the steps that when the sulfur content in the molten iron is larger than 0.100%, a double-bin and double-spray-gun mixed injection technology is adopted; otherwise, adopting a double-bin and single-gun composite injection process; wherein when a double-bin and double-spray-gun mixed injection process is adopted, CaO and Mg powder which are mixed according to a preset proportion are filled in the double bins; when a double-bin and single-gun composite injection process is adopted, CaO powder and Mg powder are respectively filled in the double bins. Different injection technologies are selected according to the sulfur content in the molten iron, the desulfurization requirements of high-sulfur and low-sulfur molten iron can be accurately met, the purpose of efficient and rapid desulfurization of a desulfurization station is achieved, time matching of the desulfurization process and the converter and continuous casting process is achieved, the steelmaking production and quality stability control capacity is improved, and the production cost is reduced. And the steelmaking production cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of molten iron pretreatment, and in particular to a high-efficiency desulfurization method and system for sulfur-containing molten iron. Background Art

[0002] The sulfur element in steel can cause hot brittleness of steel, increase segregation during the pouring process, and the inclusions generated by it can also reduce the toughness and ductility of steel, reducing the quality of steel. It is one of the harmful elements in steel. Therefore, in the production of most steel products, harmful impurities such as sulfur and phosphorus are removed as much as possible, and hot metal desulfurization has become an indispensable key process for modern steel companies. At present, steel companies generally set up hot metal pretreatment to improve the conditions for entering the converter, which is the main means to improve steelmaking operations and improve the quality of steel grades. Among them, single injection, composite injection and KR method (also known as mechanical stirring method) have become the mainstream desulfurization process.

[0003] Both granular magnesium and composite desulfurizer desulfurization belong to the spraying method. The desulfurizer containing CaO, Mg, and CaF2 is blown into the molten iron below the liquid surface through a spray gun using a carrier gas (N2 or Ar2). The bottom of the spray gun is generally 100-300mm away from the bottom of the iron ladle. The molten iron is stirred by the reaction of the blown carrier gas and the magnesium-based desulfurizer. The sulfur element in the molten iron reacts chemically with the added desulfurizer to form desulfurization products, which are then desulfurized by floating and slag removal. Granular magnesium spraying is a single passivated / coated granular magnesium sprayed into the molten iron through a spray gun with a vaporization chamber for desulfurization; composite desulfurizer spraying is a method of spraying desulfurization with (Mg+CaO) mixed in a certain proportion in advance. Lime has a certain degree of desulfurization effect, while dispersing magnesium bubbles, reducing the growth diameter of magnesium bubbles, reducing the floating speed of magnesium bubbles, and increasing the effective surface area of ​​magnesium, thereby enhancing the solubility of magnesium in molten iron.

[0004] The KR stirring method is a hot metal desulfurization technology used in industrial production by Nippon Steel Corporation in 1965. The KR desulfurization method is to insert a stirrer made of refractory materials into the hot metal to a certain depth and rotate it. The hot metal surface forms a "V"-shaped vortex, so that the added desulfurizer is dispersed in the end area of ​​the blade due to turbulence and "spitted out" along the radial direction. In this way, the desulfurizer contacts, mixes and stirs the hot metal to achieve the purpose of desulfurization.

[0005] KR desulfurization has obvious advantages in achieving deep desulfurization of molten iron and desulfurization stability, but it has obvious shortcomings in the desulfurization of high-sulfur molten iron. There are problems such as large amount of desulfurizer, large clearance requirement for the iron ladle, large temperature drop and long desulfurization time.

[0006] Xichang Steel and Vanadium uses vanadium-titanium magnetite for smelting, and the sulfur content of molten iron is above 0.15%, and can reach up to 0.25%. The target S of molten iron pretreatment is usually required to be controlled within 0.003%. The desulfurization time of KR desulfurization and traditional injection desulfurization is more than 35 minutes, plus the slag removal time, which cannot match the converter smelting and casting machine. The traditional desulfurization process has the problems of long desulfurization time, low desulfurization efficiency, and failure to meet the furnace machine matching when desulfurizing high-sulfur molten iron. Based on this, the existing technology still needs to be improved. Summary of the invention

[0007] In view of this, the present invention provides a method and system for efficient desulfurization of molten iron / semi-steel. By adjusting the CaO / Mg ratio of furnace desulfurization, the insertion depth of the spray gun, the spraying timing and flow rate, and the process and combination of the spraying speed, the purpose of efficient and rapid desulfurization in the desulfurization station is achieved, and the time matching of the desulfurization process with the converter and continuous casting process is achieved, thereby improving the production and quality stability control capabilities of steelmaking and reducing the production cost of steelmaking.

[0008] The first aspect of the present invention provides a method for efficiently desulfurizing sulfur-containing molten iron, comprising: When the sulfur content in the molten iron is greater than 0.100%, a double silo and double spray gun mixed spraying process is adopted; Otherwise, use double silo, single gun composite blowing process; Wherein, when the double-bin and double-spray gun mixed spraying process is adopted, the double-bin is filled with CaO and Mg powders mixed in a preset ratio; When the double-bin and single-gun composite injection process is adopted, the double-bin is respectively filled with CaO and Mg powders.

[0009] In some embodiments, when the sulfur content in the molten iron is 0.050%-0.070%, the injection rate of Mg is set to 7-10 kg / min, and the injection rate of CaO is set to 20-40 kg / min; When the sulfur content in the molten iron is 0.071%-0.100%, the injection rate of Mg is set to 10-12kg / min, and the injection rate of CaO is set to 30-45kg / min.

[0010] In some embodiments, when the sulfur content in the molten iron is greater than 0.100%, the spraying speed of the dual spray guns is set to increase step by step along the spraying sequence.

[0011] In some embodiments, when the sulfur content in the molten iron is greater than 0.100%, the preset ratio of the CaO and Mg mixed powders in each silo is set to decrease as the sulfur content in the molten iron increases.

[0012] In some embodiments, the double spray guns are divided into a first spray gun and a second spray gun according to their insertion depth, and the insertion depth of the second spray gun is greater than the insertion depth of the first spray gun; when the sulfur content in the molten iron is greater than 0.100%, in the same timing, the blowing speed of the second spray gun is set to be greater than the blowing speed of the first spray gun.

[0013] In some embodiments, the spray gun uses nitrogen as a carrier gas, the spray flow rate of each spray gun circuit is set to 15-45 kg / min, and the spray time is set to be longer than the time required for actual desulfurization.

[0014] In some embodiments, when a double-bin, double-spray gun mixed spraying process is adopted, the mixing ratio of CaO and Mg powders in the double-bin is set to 3-5:1.

[0015] In some embodiments, each spray gun is configured to be movable up and down within a preset range.

[0016] A second aspect of the present invention provides a high-efficiency desulfurization system for sulfur-containing molten iron, the high-efficiency desulfurization system is used to carry out the method as described above, comprising: Desulfurization agent silo system is used to supply desulfurization agent.

[0017] The spray tank system includes two silos connected to the desulfurizer silo system through a feed pipe.

[0018] The dual-circuit spray gun system comprises two spray guns respectively connected to two silos through two spray gun pipelines.

[0019] The pipeline control valve is installed at the bottom of the two silos to control the delivery and injection speed of the desulfurizer.

[0020] The spray gun pipeline switching valve group is arranged on the spray gun pipeline between the dual-way spray gun system and the spray tank system, and is used to switch the spray gun pipeline of the dual-way spray gun system.

[0021] In some embodiments, the efficient desulfurization system for sulfur-containing molten iron also includes a lance lifting system, which is used to control the lifting and lowering movements of two lances.

[0022] The beneficial effects of the present invention are as follows: by selecting different injection processes according to the sulfur content in the molten iron, the present method can accurately respond to the desulfurization needs of high-sulfur and low-sulfur molten iron. Specifically, when the sulfur content in the molten iron is greater than 0.100%, a double-bin, double-spray gun mixed injection process is adopted to quickly and efficiently reduce the sulfur content. When the sulfur content is low, a double-bin, single-gun composite injection process is adopted to ensure the desulfurization effect, avoid excessive injection, and save desulfurizer. Moreover, the present application can achieve time matching of the desulfurization process with the converter and continuous casting process without changing the injection system, thereby improving the production and quality stability control capabilities of steelmaking and reducing the production cost of steelmaking. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying creative work.

[0024] Figure 1 A schematic diagram of a high-efficiency desulfurization system for sulfur-containing molten iron provided in accordance with an embodiment of the present invention.

[0025] Description of reference numerals: a. Desulfurizer silo system; b. Spray tank system; c. Pipeline control valve; d. Dual-way spray gun system; e. Spray gun lifting system; f. Spray gun pipeline switching valve group. DETAILED DESCRIPTION

[0026] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0027] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. The subsequent embodiments will not explain this one by one.

[0028] The first aspect of the present invention provides a method for efficiently desulfurizing sulfur-containing molten iron, comprising: When the sulfur content in the molten iron is greater than 0.100%, a double silo and double spray gun mixed spraying process is adopted; Otherwise, use double silo, single gun composite blowing process; Wherein, when the double-bin and double-spray gun mixed spraying process is adopted, the double-bin is filled with CaO and Mg powders mixed in a preset ratio; When the double-bin and single-gun composite injection process is adopted, the double-bin is respectively filled with CaO and Mg powders.

[0029] In the embodiment of the present invention, the preset ratio may represent a mass ratio of CaO to Mg.

[0030] Compared with the prior art, the present invention can accurately respond to the desulfurization needs of high-sulfur and low-sulfur molten iron by selecting different injection processes according to the sulfur content in the molten iron. Specifically, when the sulfur content in the molten iron is greater than 0.100%, a double-bin, double-spray gun mixed injection process is adopted to quickly and efficiently reduce the sulfur content; and when the sulfur content is low, a double-bin, single-gun composite injection process is adopted, which can not only ensure the desulfurization effect, but also avoid excessive injection and save desulfurizer. Moreover, the present application can achieve time matching of the desulfurization process with the converter and continuous casting process without changing the injection system, thereby improving the production and quality stability control capabilities of steelmaking and reducing the production cost of steelmaking.

[0031] In some embodiments, when the sulfur content in the molten iron is 0.050%~0.070%, the injection rate of Mg is set to 7~10kg / min, and the injection rate of CaO is set to 20~40kg / min. At this time, the amount of desulfurizer can meet the desulfurization demand while avoiding excessive injection and saving costs. When the sulfur content is 0.071%~0.100%, the injection rate of Mg is increased to 10~12kg / min, and the injection rate of CaO is increased to 30~45kg / min. This adjustment can ensure that the desulfurizer can diffuse quickly and evenly under high sulfur content conditions, improve desulfurization efficiency, and reduce desulfurization time. In this injection process, the insertion depth of the spray gun is controlled according to 50~100mm from the bottom.

[0032] In some embodiments, when the sulfur content in the molten iron is greater than 0.100%, the spraying speed of the double spray gun is set to increase step by step with the spraying sequence. Since the desulfurization process of high-sulfur molten iron requires a rapid reduction in sulfur content, the spraying speed increases step by step over time to ensure that the desulfurizer is more evenly distributed in the molten iron, and the gradually increased spraying speed can better adapt to the dynamic requirements of the desulfurization reaction. The gradually increased spraying speed can enhance the mixing effect of the desulfurizer and the molten iron, especially in the initial stage of spraying, because the initial reaction of the desulfurizer and the molten iron is more intense, the lower spraying speed can avoid excessive impact on the molten iron, and as the spraying time increases, the reaction speed begins to decrease, and the gradually increased spraying speed can ensure that the desulfurizer is fully diffused and improve the desulfurization efficiency.

[0033] In some embodiments, when the sulfur content in the molten iron is greater than 0.100%, the preset ratio of the mixed powder of CaO and Mg in each silo is set to decrease as the sulfur content in the molten iron increases. As the sulfur content in the molten iron increases, reducing the proportion of CaO can more effectively utilize the strong desulfurization ability of Mg. The binding ability of Mg with sulfur is several dozen times higher than that of CaO. Therefore, under high sulfur content conditions, appropriately increasing the proportion of Mg can reduce the sulfur content more quickly. Specifically, when the sulfur content in the molten iron is 0.101%~0.140%, the preset ratio of the mixed powder of CaO and Mg in each silo is set to 4:1; when the sulfur content in the molten iron is 0.141%~0.180%, the preset ratio of the mixed powder of CaO and Mg in each silo is set to 3.5:1; when the sulfur content in the molten iron is >0.181%, the preset ratio of the mixed powder of CaO and Mg in each silo is set to 3:1.

[0034] In some embodiments, the double spray guns are divided into a first spray gun and a second spray gun according to their insertion depth, and the insertion depth of the second spray gun is greater than the insertion depth of the first spray gun; for example, the insertion depth H1 of the first spray gun is controlled at 80 to 150 mm from the bottom, and the insertion depth H2 of the second spray gun is controlled at 50 to 70 mm from the bottom.

[0035] When the sulfur content in the molten iron is greater than 0.100%, the spraying speed set for the second spray gun is greater than the spraying speed set for the first spray gun in the same time sequence. The second spray gun has a deeper insertion depth and can spray the desulfurizer directly into the molten iron, while the first spray gun mainly acts on the surface of the molten iron or shallower areas. By setting the spraying speed of the second spray gun to be greater than that of the first spray gun, it can ensure that the desulfurizer is more evenly distributed in the molten iron, thereby improving the desulfurization efficiency.

[0036] Specifically, for example, if the sulfur content in the molten iron is 0.101%~0.140%, within 0~5min, the blowing speed of the first spray gun is set to 10~20kg / min, and the blowing speed of the second spray gun is set to 20~25kg / min; within 5~10min, the blowing speed of the first spray gun is set to 20~30kg / min, and the blowing speed of the second spray gun is set to 30~35kg / min; within 10min~the end time, the blowing speed of the first spray gun is set to 20~25kg / min, and the blowing speed of the second spray gun is set to 35~40kg / min.

[0037] If the sulfur content in the molten iron is 0.141%-~0.180%, within 0~5min, set the blowing speed of the first spray gun to 15~20kg / min, and set the blowing speed of the second spray gun to 25~30kg / min; within 5~10min, set the blowing speed of the first spray gun to 30~40kg / min, and set the blowing speed of the second spray gun to 35~40kg / min; within 10min~the end time, set the blowing speed of the first spray gun to 25~30kg / min, and set the blowing speed of the second spray gun to 35~40kg / min.

[0038] If the sulfur content of molten iron is >0.181%, within 0~5min, set the blowing speed of the first spray gun to 20~30kg / min, and set the blowing speed of the second spray gun to 30~35kg / min; within 5~10min, set the blowing speed of the first spray gun to 40~45kg / min, and set the blowing speed of the second spray gun to 40~45kg / min; from 10min to the end time, set the blowing speed of the first spray gun to 25~35kg / min, and set the blowing speed of the second spray gun to 35~40kg / min.

[0039] In some embodiments, the spray gun uses nitrogen as carrier gas, the spray flow rate of each spray gun circuit is set to 15-45 kg / min, the double-channel spray flow rate is 30-90 kg / min, and the spray time is set to be greater than the actual desulfurization time, that is, the spray time t=T+30s, where T is the actual desulfurization time, and +30s is to allow the desulfurizer powder in the spray gun to be further discharged to prevent the spray gun from being blocked. The spray intensity is: low intensity in the early stage-high intensity in the middle stage-low intensity in the late stage.

[0040] In some embodiments, when a double-bin, double-spray gun mixed spraying process is adopted, the mixing ratio of CaO and Mg powder in the double-bin is set to 3~5:1. During the mixed spraying process, the presence of CaO can improve the fluidization effect of the spraying powder, reduce the blockage phenomenon during the spraying process, and improve the uniformity and stability of the spraying. By adjusting the ratio of CaO and Mg, molten iron with different sulfur contents can be flexibly responded to. For example, when the sulfur content is high, appropriately increasing the proportion of Mg can quickly reduce the sulfur content; when the sulfur content is low, a higher CaO ratio can reduce the waste of Mg.

[0041] In some embodiments, each spray gun is configured to be movable up and down within a preset range. Specifically, for example, the insertion depth H1 of the first spray gun is controlled at 80 to 150 mm from the bottom, and the insertion depth H2 of the second spray gun is controlled at 50 to 70 mm from the bottom, and the relative height difference between the two spray guns is 40 to 80 mm. The movable movement of the spray gun can dynamically adjust the spraying position according to the height of the molten iron liquid level and the needs of the desulfurization process, so that the desulfurizer can be more evenly distributed in the molten iron, especially when the molten iron liquid level fluctuates, the spray gun can flexibly adjust the height to ensure that the desulfurizer is fully in contact with the molten iron, thereby improving the desulfurization efficiency.

[0042] The second aspect of the present invention provides a high-efficiency desulfurization system for sulfur-containing molten iron, such as Figure 1 As shown, including: Desulfurizer silo system a is used to supply desulfurizer, which includes CaO and Mg powder.

[0043] The spray tank system b includes two silos connected to the desulfurizer silo system a through a feed pipe; the two silos are arranged in parallel and are filled with one or a mixture of CaO and Mg powders as required.

[0044] The dual-path spray gun system d comprises two spray guns respectively connected to two silos through two spray gun pipelines. The spray guns are inserted into the molten iron to introduce the desulfurizer into the molten iron.

[0045] The pipeline control valve c is arranged at the lower part of the two silos and is used to control the conveying and injection speed of the desulfurizer.

[0046] The spray gun pipeline switching valve group f is arranged on the spray gun pipeline between the dual-way spray gun system d and the spray tank system b, and is used to switch the spray gun pipeline of the dual-way spray gun system d. Figure 1 As shown, the spray gun pipeline switching valve group f includes a vertical valve arranged between the two spray gun pipelines and two horizontal valves respectively arranged on the two spray gun pipelines. When the double-bin and double-gun mixed spraying process is adopted, the vertical valve is closed, the two horizontal valves are opened, and nitrogen is passed to the two spray guns, so that the two spray guns spray the desulfurizer into the molten iron. When the double-bin and single-gun composite spraying process is adopted, one of the horizontal valves is closed, and the vertical valve and the other horizontal valve are opened, so that the desulfurizers in the two bins are mixed in the spray gun and then sprayed into the molten iron.

[0047] In some embodiments, the efficient desulfurization system for sulfur-containing molten iron also includes a spray gun lifting system e, which is used to control the lifting and movement of two spray guns to dynamically adjust the spraying position according to the height of the molten iron liquid level and the needs of the desulfurization process, so that the desulfurizer can be more evenly distributed in the molten iron, ensuring that the desulfurizer is in full contact with the molten iron, thereby improving the desulfurization efficiency.

[0048] The following is a further description of the efficient desulfurization method for sulfur-containing molten iron provided by the present application in conjunction with specific embodiments: A steel plant currently has three 200-ton desulfurization injection systems, which use semi-steel or molten iron after vanadium extraction for desulfurization. The converter smelting cycle time is 35 minutes, matching the pouring time of the slab continuous casting machine. The desulfurization process used is the injection method. When the sulfur content in the molten iron is >0.08%, the desulfurization time exceeds 35 minutes (including 7 minutes of slag removal time), resulting in a long desulfurization time and the converter needs to wait for molten iron. When the sulfur content in the molten iron is >0.100%, the casting machine needs to slow down and wait for semi-steel smelting, which is not conducive to production quality control.

[0049] After adopting the high-efficiency desulfurization technology of sulfur-containing molten iron of the present application, when the sulfur content in the molten iron is less than 0.100%, the above-mentioned double-bin, single-gun composite blowing process is used for high-intensity blowing, and the blowing flow rate of the single-gun circuit is increased to 15~45kg / min, which can increase the desulfurization intensity and reduce the desulfurization time, and the CaO / Mg ratio of the slag is appropriate, which is easy to slag and effectively inhibit the return of sulfur; when the sulfur content in the molten iron is greater than 0.100%, the above-mentioned double-bin, double-gun mixed blowing process is used for high-efficiency blowing in stages, and the blowing flow rate of the double-gun circuit is increased to 30~90kg / min, which significantly increases the desulfurization intensity and reduces the desulfurization time. According to statistics, when the sulfur content in the molten iron is 0.15%, the original single-gun blowing time requires 37min, and the blowing time of this method is only 20min, and each tank of molten iron can save 15min of blowing time, and the desulfurization time and temperature loss are significantly improved, and the slag iron loss is reduced, which saves steel materials significantly.

[0050] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A method for efficiently desulfurizing sulfur-containing molten iron, characterized in that: include: When the sulfur content in the molten iron is greater than 0.100%, a double silo and double spray gun mixed spraying process is adopted; Otherwise, use double silo, single gun composite blowing process; Wherein, when the double-bin and double-spray gun mixed spraying process is adopted, the double-bin is filled with CaO and Mg powders mixed in a preset ratio; When the double-bin and single-gun composite spraying process is adopted, the double-bin is respectively filled with powders of CaO and Mg.

2. The method for efficiently desulfurizing sulfur-containing molten iron according to claim 1, characterized in that: When the sulfur content in the molten iron is 0.050%-0.070%, the injection rate of Mg is set to 7-10kg / min, and the injection rate of CaO is set to 20-40kg / min; When the sulfur content in the molten iron is 0.071%-0.100%, the injection rate of Mg is set to 10-12kg / min, and the injection rate of CaO is set to 30-45kg / min.

3. The efficient desulfurization method of sulfur-containing molten iron according to claim 1, characterized in that: When the sulfur content in the molten iron is greater than 0.100%, the spraying speed of the double spray guns is set to increase step by step along the spraying sequence.

4. The efficient desulfurization method of sulfur-containing molten iron according to claim 3, characterized in that: When the sulfur content in the molten iron is greater than 0.100%, the preset ratio of the CaO and Mg mixed powders in each silo is set to decrease as the sulfur content in the molten iron increases.

5. The method for efficient desulfurization of sulfur-containing molten iron according to claim 4, characterized in that: According to the insertion depth of the double spray gun, it is divided into a first spray gun and a second spray gun, and the insertion depth of the second spray gun is greater than the insertion depth of the first spray gun; when the sulfur content in the molten iron is greater than 0.100%, in the same time sequence, the blowing speed of the second spray gun is set to be greater than the blowing speed of the first spray gun.

6. The method for efficient desulfurization of sulfur-containing molten iron according to claim 1, characterized in that: The spray gun uses nitrogen as carrier gas, the spray flow rate of each spray gun circuit is set to 15-45 kg / min, and the spray time is set to be longer than the time required for actual desulfurization.

7. The method for efficient desulfurization of sulfur-containing molten iron according to claim 1, characterized in that: When the double-bin and double-spray gun mixed spraying process is adopted, the mixing ratio of CaO and Mg powder in the double-bin is set to 3-5:

1.

8. The method for efficient desulfurization of sulfur-containing molten iron according to claim 1, characterized in that: Each of the spray guns is arranged to be able to move up and down within a preset range.

9. An efficient desulfurization system for sulfur-containing molten iron, characterized in that: The high-efficiency desulfurization system is used to carry out the method according to any one of claims 1 to 8, comprising: Desulfurizer silo system, used to supply desulfurizer; The spray tank system includes two silos connected to the desulfurizer silo system through a feed pipe; A dual-circuit spray gun system includes two spray guns connected to two silos through two spray gun pipelines; The pipeline control valve is installed at the bottom of the two silos to control the delivery and injection speed of the desulfurizer; The spray gun pipeline switching valve group is arranged on the spray gun pipeline between the dual-way spray gun system and the spray tank system, and is used for switching the spray gun pipeline of the dual-way spray gun system.

10. The efficient desulfurization system for sulfur-containing molten iron according to claim 9, characterized in that: It also includes a spray gun lifting system, which is used to control the lifting and lowering movements of the two spray guns.

Images