JPH0435522B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a continuous refining apparatus suitable for carrying out desiliconization treatment, dephosphorization treatment, and desulfurization treatment of molten metal, particularly hot metal, either alone or in combination. In recent years, the environment in which steel materials are used has become increasingly severe, and there is a greater demand than ever for reductions in impurity elements in steel, such as phosphorus and sulfur, and for higher purification of steel materials. On the other hand, refining functions such as dephosphorization in steelmaking furnaces, such as top-blown converters, require an increase in the continuous casting ratio in the post-process and a higher tapping temperature due to the widespread use of secondary refining. Since then, it has reached its limit. Therefore, in recent years, so-called pretreatment techniques for hot metal, which perform desiliconization, dephosphorization, and desulfurization at the hot metal stage, have been actively developed and put into practical use. However, although the various hot metal treatment methods that have been proposed so far have certain advantages, they are still insufficient for practical operation, and many problems remain. For example, there are problems such as a significant temperature drop during processing, a large amount of flux used, a long time required to remove the slag, and an increase in the number of steps that complicate the manufacturing flow. There is. Generally speaking, these problems are related to desiliconization, dephosphorization,
One reason for this is that each reaction operation called desulfurization is carried out separately, and in some cases, these are carried out individually in separate reaction vessels. For example, in the past, hot metal gutter, torpedo car,
The most common method of refining is to individually charge the flux and refining agent necessary for desiliconization, dephosphorization, or desulfurization to hot metal while it passes through multiple reaction vessels such as transport ladle or converter. However, it is clear that the problems mentioned above will occur in this case. For example, apart from the converter, the containers in which these reactions are carried out were originally intended for transporting hot metal, and were not specifically designed for reaction operations, so the optimal conditions for the reactions must be maintained. In order to realize this, it is difficult to treat the essential liquid and requires separate slag removal work, which impedes the operability of the processing work.At the same time, the use of high-grade refractories and their Since repairs are essential, it usually requires a large amount of money to modify and repair multiple shipping containers. In addition, in order to improve the efficiency of refining, moderate stirring is required, especially when using CaO-based flux, fairly vigorous stirring is required, but in this case, vibration of the container and scattering of splash are involved. Trying to secure the stirring power necessary for the reaction using a torpedo car or transport pot is unreasonable in terms of equipment costs and safety. In addition, in the current situation where hot metal is refined in a plurality of reaction vessels for different purposes, it is unavoidable that the temperature decrease increases during the treatment. The present invention was made in view of the actual situation of hot metal treatment as described above, with the purpose of developing a rational hot metal treatment that carries out desiliconization, dephosphorization, and desulfurization all at once. In order to achieve this goal, we have conducted extensive research and testing on the reaction behavior of desiliconization, dephosphorization, and desulfurization of hot metal. As a result, we have obtained some new knowledge, and here we have developed the method to carry out one or more treatments of desiliconization, dephosphorization, and desulfurization of hot metal continuously and, in some cases, to simultaneously perform several reactions at high speeds. We were able to develop a very rational and highly efficient hot metal treatment method and equipment that can be carried out efficiently. In other words, the present inventors have found that the reaction is not effectively affected by the conventionally proposed and practically used methods, such as the injection of refining flux using an inert gas as a carrier gas and the injection of oxygen-enriched gas while using a cooling gas. In view of the limitations in progressing the process, we have developed a new alternative recipe: a continuous treatment method in which refining flux is ink-expelled under the surface of hot metal using oxygen-enriched gas as a carrier gas, and its method. We have developed a refining device that effectively carries out this process. The continuous processing method for hot metal developed by the present inventors is as follows:
First, a continuous stream of horizontally flowing hot metal is formed, and the refining material is directed through one or more submerged nozzles whose positions are fixed relative to the continuous flow of hot metal. Second, as this refining material, a powdery solid material and an oxygen-containing gas (preferably an oxygen concentration of 50 Vol.
% oxygen-containing gas); and third, as the hot metal passes continuously through a continuous supply zone of this refining material, the desiliconization and dephosphorization reactions are carried out sequentially or simultaneously. (In other words, the desilicification and dephosphorization are not achieved by reaction with molten slag formed on the surface of the hot water as in the past, but by the process of desilicification and dephosphorization. In addition, depending on the Si content and P content in the hot metal to be treated, the above-mentioned Several zones are set up for continuous supply of refining materials, with the upstream zone mainly performing the desiliconization reaction (however, the dephosphorization reaction may also proceed in this zone), and the downstream zone The dephosphorization reaction takes place primarily (dephosphorization and desulfurization reactions may also proceed in this zone), and the refining materials include powdery solid material and a substantially inert gas. This is a hot metal treatment method whose basic requirements are to mainly promote the desulfurization reaction in this zone by using refining substances consisting of This is a continuous treatment method for hot metal that allows one or more reactions among desiliconization, dephosphorization, and desulfurization to be carried out as appropriate depending on the S content and S content. The present invention provides a refining device that can effectively carry out such continuous treatment of hot metal. That is, as shown in FIG. 1 of the drawings, the present invention has an inlet 1 for supplying molten metal at or near one side end, and an inlet 1 for supplying molten metal at or near the other side end. In a container 3 having an outlet 2 that causes a flow of hot water to flow in a substantially horizontal direction from one side end of the container to the other side end, the inside of the container 3 is A plurality of nozzles 4 are arranged in a row at intervals in the flow direction of the hot water on the container body at the part that comes into contact with the hot water, and each nozzle 4 is used to adjust the solid-air ratio between the powder supply source 5 and the gas supply sources 6 and 7. The object of the present invention is to provide a molten metal refining apparatus, which is characterized in that the apparatus is connected through a gas composition adjustment means and a gas composition adjustment means. DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus of the present invention will be specifically described below with reference to the drawings, taking the treatment of hot metal as an example. As shown in FIG. 1, the refining vessel 3 used in the present invention is a cylindrical body that is elongated in the horizontal direction, and has a hot metal inlet 1 that continuously supplies hot metal at or near one side end. A continuous discharge outlet 2 is provided at or near the other side end, and hot metal with a predetermined retention amount is directed into the container 3 from one side end to the other side end. A unidirectional continuous flow is formed. At the bottom of the container 3, nozzles 4 are arranged at intervals in the flow direction of the hot metal to feed a refining substance consisting of powder and gas across the continuous flow of the hot metal in the container. A plurality of nozzles 4 are connected in series, and each nozzle 4 is connected to a powder supply source 5 and gas supply sources 6 and 7 via its solid-air ratio adjusting means and gas composition adjusting means. The powder supply source 5 is a supply source of mixed powder such as CaO, CaF ₂ , mill scale, iron ore, or sintered ore powder, and the gas supply source 6 is an inert gas such as argon gas or nitrogen gas, or air. The gas source 7 represents a pure oxygen source. 8 is a gas control valve that adjusts the amount of inert gas or air supplied;
9 is an oxygen control valve that adjusts the amount of pure oxygen supplied; 10
is a dispenser for dispensing powdered substances. The dispenser 10, the gas control valve 8, and the oxygen control valve 9 adjust the composition and amount of the powdery substance, the gas composition and amount, and the solid-gas ratio supplied to each nozzle 4. The adjustment of the solid-gas ratio and the gas composition will be described in detail later. As the nozzle 4, a single pipe nozzle made of refractory material as shown in FIG. 2 is used. That is, the nozzle member consisting of the refractory inner cylinder 11 and the refractory outer sheath 12 is mounted on the refractory layer 13 of the container 3 so that the inner surface of the refractory layer 13 and the nozzle tip surface are aligned. A pipe 14 made of steel (stainless steel) is inserted into the inner cylinder 11 from the outside of the container 3, and this pipe 14 is connected to the aforementioned dispenser 10 by a hose 16 via a joint 15. connected. Although the nozzle 4 is made of refractory material as described above, even if the powder is fed into the hot metal using oxygen-enriched gas as a carrier gas according to the present invention, heat is removed by the sensible heat and latent heat of the powder. A solidified shell containing hot metal metal is formed at the tip of the refractory single-tube nozzle, and this serves as a protector to prevent melting of the refractory, allowing the nozzle 4 to pass oxygen-enriched gas without melting. Powder can be injected as a carrier gas. Furthermore, depending on how they are arranged, the plurality of nozzles 4, which are arranged in a row on the container body at a portion that comes into contact with the hot water in the container 3 at intervals in the flow direction of the hot water, may cause the jet stream to spray into the container. The surface of the hot water flowing inside may be rippled at a predetermined period. for example,
When all the nozzles are arranged in a straight line at regular intervals along the flow of hot water at the center of the bottom of a semicircular container, waves with a constant period are generated. This wave motion causes a phase shift between the surface of the hot metal flowing on the right side of the nozzle 4 and the surface of the hot metal flowing on the left side, resulting in a phenomenon in which the surface of the hot metal alternately flows while being inclined. This wave motion can be effectively prevented by arranging the nozzles 4 in a staggered manner. Furthermore, even if the nozzles 4 are arranged in a straight line, the jet ports of the nozzles 4 can be alternately tilted at a predetermined inclination. This wave motion can also be suppressed by injecting at an angle in a plane perpendicular to the plane. In FIG. 1, 17 is a sliding nozzle that controls the flow rate of hot metal supplied to the container 3, and 18 is a sliding nozzle that controls the flow rate of hot metal flowing out from the container 3. By adjusting this, the flow of hot metal inside the container is controlled. The flow rate of hot metal is controlled. Reference numerals 19 to 20 are windows opened to the outside air provided in the walls of the container, and these windows are used to discharge slag generated by the refining operation to the outside of the container. Further, an opening 22 provided in the ceiling of the container 3 is a gas exhaust port, and exhaust gas exiting from the opening 22 is guided to a hood (not shown) at the top of the container 3. Moreover, 24 is a weir that dams up the flow of the generated slag. There may be one weir 24 as shown in FIG. 1, or there may be a plurality of weirs 24 as shown in FIG. In the present invention, this weir 24 is used only to stop the flow of slag, and is not used to separate reaction zones. In the present invention, the reaction zone is formed at the position where the nozzle 4 is installed, for example, this weir 24.
Even if they are not separated, a desiliconization reaction zone is formed at the nozzle position on the upstream side, and a dephosphorization zone and a desulfurization zone are formed at the nozzle position on the downstream side. In this regard, for example, Japanese Patent Publication No. 58-56006 discloses a refining furnace in which a desiliconization chamber exclusively for desiliconization is provided on the upstream side of the partition wall. In addition to being fundamentally different from the present invention in that it is a smelting furnace, the present invention differs in its actual content in that the reaction zones for desiliconization and dephosphorization are not separated by such a partition wall. are also fundamentally different. 4 and 5 show a cross section of the container in a direction perpendicular to the axis in the flow direction of hot metal, and the cylindrical container 3 is configured to be able to rotate around the axis by a rotating means 25. An example is shown. Figure 4 shows the position where the refining operation is performed, and Figure 5 shows the position rotated approximately 90 degrees when the refining operation has to be interrupted. At this approximately 90 degree rotated position, operate the nozzle 4 so that it does not come into contact with the hot water (for example, reduce the amount of hot metal retained in the container slightly).Next, the control operation of the device of the present invention will be explained. .
FIG. 6 schematically shows a control mode for carrying out the solid-gas ratio adjustment, gas composition adjustment, and hot metal flow rate adjustment of the apparatus shown in FIG. 1, and in this FIG. 27 is a powder supply speed setting device;
28 is a gas flow rate setting device, 29 is a differential pressure setting device, 30
31 represents a valve opening/closing indicator, and 31 represents a processing speed setting device. In the dispenser 10, the amount of powder supplied (supply speed) is controlled by the pressure difference between the gas supplied to the powder supply side and the powder discharge side. It can be operated suitably by using the dispenser 10, using nitrogen gas or air as the gas on the powder supply side, and using pure oxygen as the gas on the powder discharge side. Taking this as an example and explaining its control operation,
First, the processing setting conditions 32 are input to the processing condition setting device 26 . Among them, the processing speed of hot metal is set by setting device 3.
1, and the powder supply rate is set by the setting device 27. The set value for the processing speed of hot metal is sent from the setting device 31 to the controller of each sliding nozzle as a control signal for controlling the opening degrees of the sliding nozzle 17 at the inlet and the sliding nozzle 18 at the outlet, and is set at a predetermined value. It is controlled by the opening degree. On the other hand, the set value of the powder supply rate is determined by the input signal 33 of the O ₂ /N ₂ ratio and the input signal 34 of the solid-gas ratio γ, as well as the gas flow rate controller 28.
Here, the magnitude of the control signal output to obtain the required gas composition and solid-gas ratio is calculated. The result of this calculation is sent to the valve opening/closing indicator 30 and the differential pressure setting device 29. The valve opening/closing indicator 30 sends an opening/closing signal to a nitrogen or air gas opening/closing valve 35 . Moreover, the differential pressure setting device 29 is
A control signal for the opening of the gas regulating valve 8 and the pure oxygen regulating valve 9 is transmitted, and the opening of each valve 8 and 9 is controlled so that a predetermined differential pressure is obtained, and supply is provided by setting this differential pressure. The composition ratio of nitrogen and oxygen in all the gases to be used is adjusted. Since the ratio between the total gas supply amount and the powder supply amount is adjusted, the solid-gas ratio is also adjusted to a predetermined set value. In this way, in the apparatus of the present invention shown in FIG.
~30, dispenser 10, gas regulating valves 8, 9
It is composed of. By using the refining apparatus having the above configuration, desiliconization, dephosphorization, and desulfurization treatment of hot metal can be suitably carried out. The processing principle and examples will be explained below. First, a description will be given of the dephosphorization treatment when hot metal with a low Si content is targeted. When performing the dephosphorization reaction mainly on hot metal with a low Si content that does not particularly require desiliconization,
This hot metal is fed into a vessel, and an oxygen source and quicklime necessary for the dephosphorization reaction are injected through a nozzle across the continuous flow. For example, a refining substance consisting of a gas with an oxygen concentration of 50 vol % or more and a powdered solid material with a total calcium oxide and iron oxide content of 50 vol % or more is fed from a nozzle across the continuous flow of hot metal. As a result, the hot metal continuously passes through the continuous supply zone of the refining material, and the direct contact between the hot metal and the refining material effectively promotes the dephosphorization reaction. can be done. Figures 7 to 9 are graphs showing the results of tests conducted by the present inventors showing that the total amount of oxygen in the substance injected below the hot metal surface controls the dephosphorization reaction. Figure 7 shows 40% pure oxygen as carrier gas.
When a powder consisting of CaO - 10% CaF ₂ - 50% mill scale or a powder consisting of 80% CaO - 20% CaF ₂ is injected into hot metal containing approximately 0.15% by changing the feeding rate. The dephosphorization behavior of
It is organized by the basic unit of CaO supplied. The results shown in FIG. 7 show that even when organized in terms of CaO basic unit, there are variations in the dephosphorization rate, and that the dephosphorization behavior cannot be explained solely by increases and decreases in the amount of CaO. In contrast, Figure 8 shows the same test results organized by the total amount of oxygen supplied into the hot metal (the total amount of oxygen introduced as carrier gas and oxygen introduced as mill scale). In some cases, the amount of dephosphorization shows a perfect match with the total amount of oxygen. In other words, even if the type and amount of injected powdery material differs, in other words, regardless of the amount of injected CaO or _CaF2 , the amount of reactive oxygen supplied as a whole will vary. This shows that there is a direct relationship with the amount of phosphorus removed. In other words, the dephosphorization reaction depends on the total amount of oxygen supplied to the hot metal,
In other words, the rate is determined by the sum of the oxygen gas and the amount of oxygen in the iron oxide in the mill scale. Also, the 9th
The figure shows the results of the same tests as above except that nitrogen gas was used as the carrier gas, and the results of the injection using nitrogen gas as the carrier gas and the injection using oxygen gas as the carrier gas. However, in the latter case, it is shown that a remarkable dephosphorization effect can be obtained with a very small amount of powder per unit. That is, it can be seen that extremely effective dephosphorization can be carried out when the oxygen source consisting of gas and powder is brought into direct contact with the hot metal. The inventors of the present invention repeated numerous tests in addition to the above tests, and found that using a gas with an oxygen concentration of 50 vol% or more as a carrier gas, a powder material with a total content of calcium oxide and iron oxide of 50% by weight or more was converted into a solid gas. Ratio (Kg/Nm ³ ) is 4~
It was confirmed that good dephosphorization treatment can be achieved when supplied at a concentration of 50%. That is, by continuously supplying such an oxygen source consisting of gaseous oxygen and solid oxygen from a nozzle across the continuous flow of hot metal, the hot metal is caused to continuously pass through this continuous oxygen supply zone. By direct contact between the two, the dephosphorization reaction can proceed continuously and effectively. In this case, the CaO contained in the powder material seems to play a role in fixing and floating phosphorus oxide, which is produced by the reaction between P in the hot metal and oxygen as an oxygen source. Also, an appropriate amount
The present inventors have experimentally confirmed that when CaF ₂ is simultaneously injected, the dephosphorization efficiency can be significantly improved compared to CaO alone, CaO-NaF, or CaO-CaCl ₂ systems. In addition, in this dephosphorization process, when the hot metal passes through the supply zone of the refining substance, desulfurization may also proceed simultaneously with dephosphorization. However, the degree of desulfurization usually does not progress to the very low range as much as dephosphorization does, so if desulfurization is intended to reach the very low range, dephosphorization may progress as described below. It is preferred that the hot metal is passed through a feed zone of a different refining substance than that for dephosphorization. Next, a case will be described in which desiliconization is performed on hot metal with a high Si content. In this desiliconization treatment, as in the above-mentioned dephosphorization treatment, the hot metal is supplied to a container, and an oxygen source necessary for the desiliconization reaction is injected from a nozzle across the continuous flow. For example, powder mixed with a gas with an oxygen concentration of 50 Vol% or more and a ratio of calcium oxide to iron oxide (CaO/iron oxide ratio) in the range of 0.6 to 1.5 such that the total amount of both is 90% by weight or more. material is fed from a nozzle across a continuous stream of hot metal. This allows the hot metal to pass continuously through the continuous supply zone of the refining material, during which the desiliconization reaction is effected by the direct contact between the hot metal and the refining material. progress as expected. According to the results of many tests conducted by the inventors,
Gas with an oxygen concentration of 50 Vol% or more and a ratio of calcium oxide to iron oxide (CaO/iron oxide ratio) of 0.6 to 1.5
When the method of the present invention is carried out using a powdered material blended so that the total amount of both is 90% by weight or more, and a refining material consisting of It has been found that the desiliconization process can be carried out with almost no forming phenomenon and that the desiliconization reaction proceeds very quickly. In addition, in this desiliconization treatment, dephosphorization may also proceed at the same time as the hot metal passes through the supply zone of the refining substance for desiliconization, even if not intended. This dephosphorization progresses particularly markedly when the Si content in the hot metal becomes low. Therefore, when a plurality of desiliconization zones are formed in the flow direction of hot metal by supplying the refining material for desiliconization from any of the plurality of nozzles as shown in FIG. Since the Si content in the steel becomes low, the desiliconization and dephosphorization reactions proceed in parallel on this downstream side. However, if dephosphorization is specifically intended and dephosphorization is to be carried out to a very low level, it is preferable to have the hot metal pass through the dephosphorization zone after the desiliconization zone, as described below. In other words, when dephosphorizing hot metal with a high Si content, the hot metal that has undergone the desiliconization treatment must be continuously supplied to the dephosphorization zone that uses the dephosphorization refining material. Bye. More specifically, an oxygen source necessary for the desiliconization reaction is first injected across a continuous flow of hot metal containing high Si content and P. For example, as mentioned above, this is a gas with an oxygen concentration of 50 Vol% or more and a ratio of calcium oxide to iron oxide (CaO/iron oxide ratio) of 0.6 to
1.5, and the powder material is blended so that the total amount of both is 90% by weight or more, and is fed from a nozzle across the continuous flow of hot metal. Then, for the continuous flow of hot metal whose Si content has decreased to 0.2% or less, more preferably 0.15% or less after passing through this desiliconization zone, the oxygen concentration is 50Vol%.
The sum of the above gases, calcium oxide and iron oxide is
A dephosphorization refining material consisting of 50% by weight or more of powdered solid material is fed through a nozzle across a continuous flow of hot metal. When using the container shown in Figure 1, the desiliconization refining material is injected from the nozzle located upstream with respect to the flow of hot metal, and the dephosphorization refining material is injected from the nozzle located downstream. It is an injection. As mentioned above, the substance for desiliconization refining on the upstream side and the substance for dephosphorization refining on the downstream side may be the same, but in the latter case, a part of CaO is replaced with _CaF2 . It is more advantageous to use When performing desiliconization and subsequent dephosphorization in this way, if the intention is to separate and recover the slag floating on the surface of the hot water, in other words, slag with a low P content and When it is advantageous to utilize slag by separating it from slag with a high P content, as in the example shown in Figure 3,
A weir 24 is provided to block the flow of slag.
This can be easily achieved by providing an opening for drainage in the container wall on the upstream side of the container. Next is the desulfurization process, in which a refining substance consisting of a powdered solid substance and a substantially inert gas is fed into the hot metal from a nozzle across the continuous flow of the target hot metal. This allows the desulfurization reaction to proceed effectively in this zone. Nitrogen gas, argon gas, etc. are used as the inert gas. Soda ash or the like is suitable as the powdery solid substance. When attempting to desulfurize hot metal that does not require desiliconization or dephosphorization, this low-Si and low-P hot metal can be supplied to the refining equipment shown in Fig. 1 to carry out the desulfurization treatment. It is practical to carry out this desulfurization treatment at the same time as and/or dephosphorization in the apparatus shown in FIG. In this case, as mentioned above, during the dephosphorization treatment operation in which the hot metal passes through the dephosphorization zone, desulfurization also proceeds to some extent in parallel, but it is better to pass the hot metal after passing through the dephosphorization zone to the desulfurization zone. . In other words, it is preferable to provide the desulfurization zone on the lower sulfurization side of the dephosphorization zone. In this way, by using the refining apparatus of the present invention, it is possible to carry out either one of desiliconization, dephosphorization, or desulfurization alone, or to carry out both of desiliconization, dephosphorization, and desulfurization. It is also possible to combine more than one species and carry out in a complex manner simultaneously or in parallel.
The selection depends on the Si content in the hot metal to be treated, P
It is determined by the content and S content, but the basic point is that a continuous flow of hot metal flowing horizontally is formed in the container, and one or more nozzles are fixed at the part in contact with this continuous flow. Therefore, a refining substance consisting of a powdered solid substance and an oxygen-containing gas or an inert gas is continuously supplied below the surface of the hot metal so as to cross the continuous flow of the hot metal. Thus, when hot metal continuously passes through this continuous supply zone of refining substances, the desired continuous and effective desiliconization, dephosphorization, or desulfurization treatment is achieved. The test described below was 400mm wide and 3m long.
The refining device is a reaction vessel with a bath depth of 600 mm and a capacity of 5 tons as shown in Figure 1, with nine nozzles arranged at intervals of about 25 cm along the flow direction of the hot water at the bottom of the vessel. This was carried out using Each nozzle is a single refractory nozzle with an inner diameter of 5 mm.
The cross section of the container in the direction perpendicular to the axis along the flow direction of the hot metal is rectangular, unlike in FIGS. 3 and 4. As shown in FIG. 10, the zone where five upstream nozzles are located is called A zone, the downstream zone where four nozzles are located is called B zone, and the downstream zone where there are no nozzles is called C zone. Different types of refining substances were introduced into the A zone nozzle and the B zone nozzle as described in each example below. During the treatment, before the hot metal to be treated flows in, a 5 ton high-frequency induction furnace is used to artificially prepare molten metal and this is poured into the container for 50 minutes.
After that, approximately 60 tons of blast furnace hot metal to be treated was continuously treated in a treatment time of approximately 150 minutes. At that time, the treated hot metal was discharged from the vessel in an amount commensurate with the amount of hot metal introduced. Example 1 The chemical components in hot metal are C: 4.6%, Si: 0.42%,
Mn: 0.43%, P: 0.115%, S: 0.035%,
Blast furnace hot metal with a temperature of 1410 to 1320℃ is used as the hot metal to be treated, and each of the five nozzles in the A zone is heated with 80Vol%.
Oxygen + 20Vol% nitrogen gas is flowed at a flow rate of 120N/min, and this gas is used as a carrier gas at 50N/min.
%CaO + 50% mill scale
Kg/(min・pieces), and each of the four nozzles in the B zone is supplied with 80Vol%.
Oxygen + 20Vol% nitrogen gas is flowed at a flow rate of 120N/min, and this gas is used as a carrier gas at 40N/min.
%CaO + 10% CaF ₂ + 50% mill scale under the refining material supply conditions of 1 kg/(min・piece), the blast furnace hot metal was mixed with the seed metal described above. Continuous treatment was carried out in which a total of 62 tons of water was fed into the container at a feed rate of 400 kg/min. Samples for analysis were collected from locations corresponding to each nozzle position just before 150 minutes had elapsed since the introduction of hot metal into the blast furnace, and the Si content, P content, and S content during processing in each zone shown in Figure 10 are shown. The first one was
Figure 1. In addition, the left column of Fig. 13 shows the results of examining the P content of treated hot metal taken out from the container every moment from the start to the end of this example. . As seen in FIG. 11, a rapid desiliconization reaction progresses in the A zone. And this A
In the later stages of the zone, where the Si content has decreased to around 0.1%, dephosphorization and desulfurization have begun to progress. When entering the B zone, dephosphorization progresses even further to the lower regions, and desulfurization also progresses at the same time. The results shown in Figure 13 show that the P concentration in the treated hot metal changes between 0.03 and 0.04% approximately 15 minutes after the start of treatment, indicating that extremely stable simultaneous dephosphorization and desiliconization treatment is being performed. It shows that In addition, the first
The P concentration at the treatment time of 0 in Figure 3 is the concentration of the seed water, and is therefore out of scope. The total flux unit in this example is approximately 35Kg/ton (CaO: 16.5Kg/ton), which is compared to the flux source unit in the currently known method of desiliconization and dephosphorization of hot metal. This is a significantly small amount. In any conventional hot metal treatment method, there is no example of successful dephosphorization of hot metal with a Si concentration of about 0.4% at a flux amount of about 35 kg/ton.
With such a small amount of flux, conventional methods can only remove Si to 0.10 to 0.15%, and usually do not reach the level of dephosphorization. Therefore, it can be said that according to the present invention, the desiliconization and dephosphorization reactions proceed with extremely high reaction efficiency. Example 2 Hot metal that differs from the hot metal of Example 1 only in that the Si content is 0.13% is used, and following the treatment of Example 1, this hot metal with a Si content of 0.13% is treated under the same conditions as Example 1. Continuously processed. That is, the Si content of the hot metal to be supplied to the previously described refining vessel in which the hot metal in the continuous treatment process of Example 1 is present is adjusted in advance.
The same treatment as in Example 1 was carried out by switching to hot metal with a lower concentration of 0.13%. The feeding speed of hot metal is as in Example 1.
It was the same as 400Kg/min, and the throughput was 57 tons. Immediately before the end of this process, samples for analysis are collected from locations corresponding to each nozzle position, and their Si content and
The P content and S content are shown in FIG. 12 in the same relationship as in FIG. 11 above. The right column of FIG. 13 shows the results of examining the P content of treated hot metal taken out from the container every moment from the start to the end of this example. As seen in FIG. 12, desiliconization is completed on the upstream side of zone A, and along with this, dephosphorization progresses considerably while passing through zone A. At the same time, desulfurization is also partially progressing in this A zone. When entering the B zone, dephosphorization and desulfurization proceed simultaneously. Also, the results in Figure 13 are approximately 15% after the start of processing.
After 10 minutes, the P concentration in the treated hot metal began to change around 0.01%, which is even lower than in Example 1, indicating that a very stable dephosphorization process was carried out at a low flux consumption rate. . In addition, Fig. 13 also shows the temperature change of the hot metal before treatment and the temperature of hot metal after treatment, but the degree of temperature drop is this level even with this small amount of hot metal treatment.
For large-scale processing, applying the so-called 1/3 power law and estimating the temperature ranges from 20°C to at most 50°C. In this point,
In conventional hot metal processing, a temperature drop of about 70°C is unavoidable even with dephosphorization, so this was a very advantageous result in terms of suppressing the temperature drop. In addition, in this example, the slag generated during the treatment was very well removed. Example 3 The chemical components in hot metal are C: 4.5%, Si: 0.15%,
65 tons of blast furnace hot metal with Mn: 0.45%, P: 0.110%, and S: 0.037% at a temperature of 1340°C was injected into each of the five nozzles in the A zone at 80Vol%.
Oxygen + 20Vol% nitrogen gas is flowed at a flow rate of 120N/min, and this gas is used as a carrier gas at 40N/min.
A powdery substance consisting of %CaO + 10% CaF ₂ + 50% Lescale was injected at a rate of 2.0Kg/(min・piece), and nitrogen gas was injected at 40N/min into each of the four nozzles in the B zone. At the same time, using this nitrogen gas as a carrier gas, soda ash is added at a flow rate of 0.4 kg/
Continuous processing was carried out in the same manner as in the previous example, under the in-die extraction condition of injecting at an amount of (min/units). When continuous processing has stabilized, samples for analysis are collected from locations corresponding to each nozzle position.
The Si content, P content and S content are shown in FIG. 14 in the same relationship as in FIG. 11 above.
Table 1 also shows the average values of each chemical component collected at the entrance of zone B and zone C.

[Table] From Figure 14 and Table 1, it can be seen that in zone A, the flux consumption rate is 25 kg/ton, and desiliconization (Si%:
0.15→tr.), dephosphorization (P%: 0.110→0.007) progresses, and a part of desulfurization progresses (S%: 0.037).
→0.015), and soda ash 4Kg/in B zone
It can be seen that the final desulfurization is progressing efficiently down to extremely low levels with a usage amount of 1 ton.

[Brief explanation of drawings]

Fig. 1 is an equipment layout system diagram showing an example of the refining equipment of the present invention in a schematic cross section; Fig. 2 is a sectional view showing an example of a nozzle that can be used in the equipment of Fig. 1;
The figure is a schematic sectional view showing another example of the refining device of the present invention,
Fig. 4 is a sectional view taken along the - line of the device shown in Fig. 3, Fig. 5 is a sectional view taken along the - line of the device shown in Fig. 3 rotated by 90 degrees, and Fig. 6 is for explaining the control operation of the device of the present invention. Fig. 7 is a diagram showing the relationship between the amount of CaO and the amount of dephosphorization to explain the principle of the present invention, and Fig. 8 is a diagram of the control equipment layout.
Figure 9 is a relationship diagram between total oxygen amount and phosphor removal amount to explain the principle of the present invention, Figure 9 is a relationship diagram between flux consumption rate and phosphor removal amount to explain the principle of the present invention, and Figure 10 is a relationship diagram between flux consumption and phosphor removal amount to explain the principle of the present invention. The figure is a schematic cross-sectional view showing the nozzle position for explaining an embodiment of the present invention, and FIG. 11 is a diagram showing an example of the behavior of components in hot metal when the present invention is implemented.
FIG. 12 is a diagram showing another example of the behavior of components in hot metal when the present invention is implemented, and FIG. 13 is a diagram showing changes over time in the P content in treated hot metal obtained by the continuous treatment of the present invention. 14 are diagrams showing other examples of the behavior of components in hot metal when the present invention is implemented. 1...Inlet, 2...Outlet, 3...Container, 4
... Nozzle, 5 ... Powder material supply source, 6,7 ...
Gas supply source, 8... Gas adjustment valve, 9... Oxygen adjustment valve, 10... Dispenser, 17, 18... Sliding nozzle, 19-21... Exhaust opening,
24...weir.

Claims (1)

[Scope of Claims] 1. A container having an inlet for supplying molten metal at or near one side end and an outlet for flowing molten metal at or near the other side end, the container having: A container in which a continuous flow of hot water flows substantially horizontally from one side end to the other side end. Single pipe nozzles are arranged at intervals in the flow direction of hot water, and each of these nozzles is connected to a refining powder supply source and a gas supply source containing oxygen gas through a solid-gas ratio adjustment means and a gas composition adjustment means. A molten metal refining apparatus which is connected to the nozzle and injects refining powder below the surface of the hot water using an oxygen-containing gas as a carrier gas. 2. The refining apparatus according to claim 1, wherein the molten metal is hot metal. 3. The refining device according to claim 1 or 2, wherein at least one opening communicating with the atmosphere is provided in the container body near the surface of the hot water flowing in the container. 4. The refining apparatus according to claim 1, 2, or 3, wherein the container is installed via a rotation mechanism that rotates the container itself around the flow direction of the hot water.