Rock wool manufacturing equipment and manufacturing method

Abstract

Provided is a rockwool manufacturing technology whereby cotton can be manufactured in a continuous and stable manner using a component-adjusted molten raw material. This facility comprises: a primary electric furnace that increases the temperature of a main raw material and adds a composition-adjusting material to adjust the result to have a prescribed component composition, and uses the same as a molten raw material for rockwool; a secondary electric furnace that maintains the temperature of the molten raw material continuously supplied from the primary electric furnace; a coating material supply means that supplies a molten metal surface coating material to the primary electric furnace and the secondary electric furnace; a cotton manufacturing machine that forms, into fibers, the molten raw material which has been continuously supplied from the secondary electric furnace; and a control means that controls the addition rate of the component-adjusting material to be added to the primary electric furnace. The control means acquires the component composition of the main raw material, the component composition of the component-adjusting material, the component composition and dissolution rate of the molten metal surface coating material in the primary electric furnace and the secondary electric furnace, and the cotton manufacturing efficiency and yield of rockwool, the control means being configured such that the component composition of the molten raw materials supplied from the secondary electric furnace becomes a prescribed component composition.

Description

[Technical Field]

[0001] The present invention relates to a rock wool manufacturing facility and manufacturing method, and more particularly to a technique for continuously manufacturing rock wool while adjusting its components. [Background technology]

[0002] In recent years, asbestos pollution problems have led to the rise of rock wool as a substitute for asbestos. Rock wool is a man-made mineral fiber made primarily from natural silicate ores such as basalt and andesite, which are melted in a cupola or electric furnace and then blown into fibers with a diameter of a few microns using centrifugal force or compressed air. Its main components are SiO2 and CaO, and it has excellent insulation, heat retention, fire resistance, and sound absorption properties, making it widely used in buildings, industrial facilities, industrial equipment, and other fields.

[0003] Incidentally, blast furnace slag discharged from blast furnaces has conventionally been water-granulated and reused as a cement raw material, concrete aggregate, ground improvement material, etc., but in recent years, because its composition is similar to the above-mentioned silicate ore, it has come to be used as the main raw material for rock wool.

[0004] In order to save energy, a typical method for producing rock wool using blast furnace slag as a raw material is to install a rock wool production facility near the blast furnace, transport the blast furnace slag discharged from the blast furnace in a molten state without cooling it, add auxiliary materials such as silica, adjust the composition to a predetermined level, and then mill it into cotton. For example, Patent Document 1 discloses a method in which two electric furnaces for producing rock wool are installed side by side, and the raw material charging, melting, composition adjustment, and temperature adjustment processes, and the heat retention and tapping processes are alternately repeated in the two electric furnaces, while the molten raw material is continuously supplied to the downstream process (a cotton mill). Patent Document 2 discloses a method in which two electric furnaces are connected together, and the molten blast furnace slag is melted and its composition adjusted in one electric furnace, the temperature is adjusted in the other electric furnace, and the molten raw material is then milled into cotton in the cotton mill.

[0005] In the production of rock wool, it is important to adjust the component concentrations (mainly the SiO2 concentration) of the molten slag finally discharged from the electric furnace to the desired concentration.Patent Document 3 discloses a technology in which two electric furnaces are arranged in series, and rock wool is produced by heating and adjusting the components of blast furnace molten slag in the primary electric furnace, and then adjusting the temperature in the secondary electric furnace, and the flow rate of gas bubbling into the primary electric furnace is determined based on information on the weight and components of the molten slag to be supplied, thereby stabilizing the SiO2 concentration. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 01-083535 [Patent Document 2] Japanese Patent Application Publication No. 62-065950 [Patent Document 3] Japanese Patent Application Publication No. 08-295527 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the above-mentioned conventional techniques have the following problems. In the technology of Patent Document 3, the supply of molten metal from the primary electric furnace to the secondary electric furnace is batchwise, and the volume of molten slag in the secondary electric furnace fluctuates, causing a problem that the amount of metal supplied from the secondary electric furnace cannot be stabilized due to changes in static pressure. Fluctuations in the amount of molten metal from the secondary electric furnace to the cotton mill can cause fluctuations in the density of the rock wool, which can lead to reduced productivity and yield.

[0008] The present invention has been made in consideration of the above circumstances, and its object is to provide a rock wool manufacturing facility that has two electric furnaces arranged in series and is capable of continuously and stably producing cotton from molten raw material with adjusted composition, and a rock wool manufacturing method using that facility. [Means for solving the problem]

[0009] The rock wool manufacturing equipment of the present invention, which advantageously solves the above problems, comprises a primary electric furnace that heats a main raw material to a predetermined temperature and adds a composition adjuster to adjust the composition to a predetermined composition to form a molten rock wool raw material; a secondary electric furnace that maintains the molten raw material continuously supplied from the primary electric furnace at a predetermined temperature; coating material supply means that supplies a molten metal surface coating material to each of the primary and secondary electric furnaces; a cotton making machine that turns the molten raw material continuously supplied from the secondary electric furnace into fiber; and control means that controls the addition rate of the composition adjuster to be added to the primary electric furnace.The control means is configured to obtain the composition of the main raw material, the composition of the composition adjuster, the composition and dissolution rate of the molten metal surface coating material in the primary and secondary electric furnaces, and the rock wool cotton making efficiency and yield, and to adjust the composition of the molten raw material supplied from the secondary electric furnace to a desired composition.

[0010] The manufacturing equipment for Rock Cool according to the present invention is as follows: (A) The components to be adjusted in composition in the primary electric furnace are one or more components selected from SiO2, CaO, Al2O3, and MgO; (A) the control means is configured to correct the target composition of the target component based on the composition of components other than the target component among the component compositions of the main raw material; (c) The main raw material is one or more selected from molten blast furnace slag, solidified blast furnace slag, and basalt; This is thought to be a preferable solution.

[0011] The method for manufacturing rock wool according to the present invention, which advantageously solves the above-mentioned problems, includes a first heating step in which a main raw material is supplied to a primary electric furnace, a molten metal surface coating material is added and heated, and a composition adjuster is added to form a molten raw material of a predetermined composition; a second heating step in which the molten raw material is continuously supplied from the primary electric furnace to a secondary electric furnace, a molten metal surface coating material is added into the secondary electric furnace, and the temperature is maintained; a fiberization step in which the molten raw material is continuously supplied from the secondary electric furnace to a cotton mill and fiberized from the molten raw material; and a composition adjustment step in which the composition of the main raw material, the composition of the composition adjuster, the composition and dissolution rate of the molten metal surface coating material in the primary electric furnace and the secondary electric furnace, as well as the rock wool cotton-making efficiency and yield are obtained, and the rate of addition of the composition adjuster to the primary electric furnace is controlled so that the composition of the molten raw material supplied from the secondary electric furnace becomes the desired composition.

[0012] The method for producing rock cool according to the present invention is as follows: (D) In the component adjusting step, the component of the molten raw material to be adjusted is one or more components selected from SiO2, CaO, Al2O3, and MgO; (E) in the component adjusting step, correcting the target composition of the target component based on the composition of components other than the target component among the component compositions of the main raw material; (F) The main raw material is one or more selected from molten blast furnace slag, solidified blast furnace slag, and basalt; This is thought to be a preferable solution. [Effects of the Invention]

[0013] According to the present invention, in the rock wool manufacturing equipment and manufacturing method, electric furnaces are connected in series to heat the molten raw material, and the molten raw material is controlled to have the desired temperature and component composition, and is continuously supplied to the cotton mill, so that rock wool can be manufactured with stable productivity and quality. By adjusting SiO2, CaO, etc. in the primary electric furnace and correcting for the effects of other components, the quality of the rock wool can be further improved. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic diagram showing a rock wool manufacturing facility according to one embodiment of the present invention. [Figure 2] 1A and 1B are schematic diagrams showing the top view of the electric furnace according to the embodiment, in which FIG. 1A shows the primary electric furnace and FIG. 1B shows the secondary electric furnace. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, embodiments of the present invention will be described in detail. Note that the drawings are schematic and may differ from the actual ones. Furthermore, the following embodiments exemplify equipment and methods for embodying the technical idea of the present invention, and are not intended to limit the configuration to those described below. In other words, the technical idea of the present invention can be modified in various ways within the technical scope described in the claims.

[0016] A rock wool manufacturing facility and a suitable manufacturing method according to one embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a conceptual diagram of a rock wool manufacturing facility 100 according to this embodiment. FIG. 2 is a conceptual diagram showing the top of an electric furnace. FIG. 2(a) shows a top view of a primary electric furnace, and FIG. 2(b) shows a top view of a secondary electric furnace. In this embodiment, blast furnace slag 1, which serves as the main raw material, is transported in a molten state from the blast furnace to the rock wool manufacturing facility 100 by freight cars or the like.

[0017] The rock wool manufacturing facility 100 of this embodiment includes a primary electric furnace 2, a secondary electric furnace 4, a cotton mill 5, and a cotton collection chamber 8. The product processing process PD is divided into a process for producing granular cotton and a process for forming sheet-shaped molded products. In this embodiment, two electric furnaces are arranged in series. As shown in FIG. 1 , the primary electric furnace 2 is located upstream, and the secondary electric furnace 4 is located downstream, forming a series connection. The primary electric furnace 2 contains a predetermined volume (mass W1) of molten raw material 1b. Blast furnace slag 1 is added to the primary electric furnace 2 using a charging ladle 1a through a main raw material inlet 2e provided in the electric furnace lid 2b. The lower portions of multiple (usually three) electrodes 2a inserted into the furnace through the electric furnace lid 2b are immersed in the molten raw material 1b in the primary electric furnace 2, and the molten raw material 1b is heated using power from the electrodes 2a to maintain a constant temperature (first heating step). The heating temperature is preferably approximately 1500°C.

[0018] In this embodiment, a gas bubbling lance 2d is inserted almost vertically into the center of an electric furnace lid 2b placed over the primary electric furnace 2, that is, through a lance insertion port provided corresponding to the center position of the three electrodes 2a, and its lower part is immersed in the molten raw material 1b inside the primary electric furnace 2. For example, an inert gas is supplied to the gas bubbling lance and blown into the molten raw material to form a gas bubbling region in the center of the furnace (first heating step).

[0019] The lower part of the auxiliary material feeding device 3a, which feeds a composition adjuster as the auxiliary material 3, is inserted into the lance insertion port, and the composition adjuster 3, such as silica stone or silica sand, is continuously fed into the gas bubbling zone (first heating step). The auxiliary material 3 is preferably pulverized to approximately 1000 μm or less, considering ease of addition and dissolution. The feeding speed (addition speed) V3 of the auxiliary material 3 is controlled by the control device 20 based on various operating conditions. The fed composition adjuster 3 is charged into the exposed molten material 1b, which becomes a bare surface due to the stirring action of the molten material 1b in the gas bubbling zone, thereby promoting its dissolution. The lower part of the auxiliary material feeding device 3a may be configured to feed the entire circumference of the gas bubbling lance. In this embodiment, it is preferable to supply the gas from the gas bubbling lance in an amount sufficient to completely dissolve the added composition adjuster 3.

[0020] In addition, a surface coating material is introduced onto the molten metal surface around the primary electric furnace 2 through a surface coating material introduction port 2c provided on the electric furnace lid 2b by a surface coating material introduction device 11 (first heating step). Similar to the composition adjuster 3, the surface coating material is made of silica sand. It covers the surface of the molten raw materials 1b, accumulates, and insulates the heat from the molten raw materials 1b, protecting the inner refractory of the electric furnace lid 2b. It is effective to use a surface coating material with low thermal conductivity. The melting rate and composition at the contact interface with the molten raw materials 1b are determined and input into the control device 20, which is used to control the addition rate V3 of the composition adjuster 3. Furthermore, the unmelted surface coating material provides insulation and reduces the radiant heat emitted from the surface of the molten raw materials 1b, thereby reducing the power supplied from the electrodes 2a.

[0021] In this embodiment, molten raw material 1b is continuously supplied from the primary electric furnace 2 to the secondary electric furnace 4 through a spout 4d provided on the electric furnace lid 4b of the secondary electric furnace 4 (second heating step). A predetermined volume (mass W2) of molten raw material 1b is accommodated in the secondary electric furnace 4. In this embodiment, rock wool is produced by continuously supplying the molten raw material 1b from the secondary electric furnace 4 to one or more cotton mills 5 (fiberization step). The supply rate V1 of the molten raw material 1b from the primary electric furnace 2 to the secondary electric furnace 4 is controlled so that the capacity W2 of the secondary electric furnace is constant, and is therefore equal to the sum V2 of the supply rates of the molten raw material 1b from the secondary electric furnace 4 to all the cotton mills 5.

[0022] In this embodiment, the lower portions of multiple (usually three) electrodes 4a inserted into the secondary electric furnace 4 through the electric furnace lid 4b are immersed in the molten raw materials 1b in the secondary electric furnace 4, and the molten raw materials 1b are heated by the power from the electrodes 4a to maintain a constant temperature (second heating step). In this embodiment, as in the primary electric furnace 2, a surface coating material for covering the surfaces of the molten raw materials 1b in the secondary electric furnace 4 is introduced by a surface coating material introduction device 11 through a surface coating material introduction port 4c provided in the electric furnace lid 4b (second heating step). This protects the inner surface of the electric furnace lid 4b from the heat of the molten raw materials 1b, reduces the radiant heat emitted from the surface of the molten raw materials 1b, and reduces the power supplied from the electrodes 4a. The surface coating material is the same as that used in the primary electric furnace 2, and the melting rate and composition at the contact interface with the molten raw materials 1b are input into the aforementioned control device 20 and used to control the addition rate V3 of the composition adjuster 3.

[0023] The secondary electric furnace 4 degasses the molten raw material and steadily supplies the molten raw material at high temperatures of 1500-1600°C to the next process, the spinner (spinner) 5 (second heating process). The molten raw material is continuously poured from the secondary electric furnace 4, dripped onto the outer surface of the rotating wheel 6 of the spinner 5, and thrown by centrifugal force to be converted into fiber. At the same time, high-pressure gas is passed along the length of the wheel to promote fiberization (fiberization process). The rock wool fibers 7 converted into fiber as described above are sucked and collected in the fiber collection chamber 8. The collected fibers 9 are then further sorted to remove any un-fiberized material (fiber collection process), and then sent to the product processing process PD, where they are processed into the specified product shape and size to produce rock wool products.

[0024] If the product processing process is, for example, the processing of molded products, the cotton-making efficiency U can be calculated, for example, from the amount of binder used. If the product processing process is the production of granular cotton, the cotton-making efficiency U can be calculated, for example, from the production time of a product of a given weight or volume. The product yield r can be determined by taking into account the amount of unprocessed raw material and whether or not unprocessed fiber is to be recovered in an upstream process. The obtained cotton-making efficiency U and yield r are input or transmitted to the control device 20 and used to calculate the supply speed V2 of the molten raw material 1b from the secondary electric furnace 4 to the cotton-making machine 5.

[0025] Table 1 shows an example of the chemical composition of blast furnace slag and basalt, which are the main raw materials for rock wool. The composition of rock wool suitable for thermal insulation has an acidity, or the ratio of SiO2 to CaO, of approximately 1 by mass. Therefore, when blast furnace slag is used as the main raw material, the SiO2 content must be increased by approximately 7% by mass, and when basalt is used as the main raw material, the CaO content must be increased by approximately 26% by mass. When fire resistance is important, an acidity of 1.8 or higher is preferable. When blast furnace slag is used as the main raw material, the SiO2 content must be increased by approximately 20% by mass, and when basalt is used as the main raw material, it is sufficient to leave it as is.

[0026] [Table 1]

[0027] The control means for controlling the rate at which the composition adjuster is added to the primary electric furnace includes a control device 20 and an auxiliary material feeder 3a. The auxiliary material feeder 3a is capable of feeding a fixed amount, and the feed amount of the auxiliary material 3 is controlled by a signal from the control device 20.

[0028] The control device 20 may include a control unit, a storage unit, an operation unit, a display unit, a communication unit, etc., and each unit may be connected by a bus.

[0029] The control unit is a computer composed of a central processing unit (CPU), random access memory (RAM), etc. In response to operations on the operation unit, the CPU of the control unit reads out system programs and various processing programs stored in the memory unit, for example, in a memory area that stores programs in the memory unit, and loads them into the working area of the RAM, and executes various processes described below in accordance with the loaded programs. The CPU also receives signals and data from other components via the bus, sends control signals and commands, and transmits and receives data to and from external devices via the communication unit. The communication unit is configured to communicate with other devices via wired or wireless connections.

[0030] The storage unit is configured with a non-volatile semiconductor memory such as an SSD (Solid State Drive) or a hard disk (HDD: Hard Disk Drive), etc. The storage unit may also include a removable flash memory, etc. The storage unit stores various programs, including programs for executing various processes in the control unit, parameters required for executing processes by the programs, and data such as processing results. The various programs stored in the storage unit are stored in the form of computer-readable program code, and the control unit sequentially executes operations in accordance with the program code.

[0031] The display unit may be, for example, a liquid crystal display (LCD), a CRT, or an organic light emitting diode (LED) monitor.

[0032] The communication unit includes a LAN (Local Area Network) adapter, a modem, a wireless communication device, etc., and controls transmission and reception with each device connected to the communication network. The communication unit may include a communication interface such as a network card, for example. The communication unit is capable of transmitting and receiving various types of data to and from external devices.

[0033] The operation unit includes a keyboard with cursor keys, numeric input keys, and various function keys, a mouse, a pointing device such as a touch panel, and outputs instruction signals input by key operations, mouse operations, etc. to the control unit.

[0034] The control device 20 acquires the component compositions of the main raw material 1, component adjuster 3, and surface coating material. The control device 20 can be pre-stored with the component compositions of each brand of component adjuster 3 and surface coating material. The control device 20 acquires the cotton-making efficiency U and yield r of various rock wool products from the product processing process PD. The control device 20 calculates the supply speed V2 of the molten raw material 1b from the secondary electric furnace 4 to the cotton-making machine 5, for example, using the following formula (1). In formula (1), n is an integer greater than or equal to 1 and represents the number of cotton-making machines 5 to which the molten raw material 1b is supplied from the secondary electric furnace 4, rn is the yield of the nth cotton-making machine and is a real number greater than 0 and less than or equal to 1, and Un is the cotton-making efficiency of the nth cotton-making machine, and the units of V2 and Un can be 1000 kg / Hr. V2=U1 / r1+U2 / r2...+Un / rn (1)

[0035] The control device 20 calculates the material balance of the target component M and the molten raw materials to be adjusted in the primary electric furnace 2, for example, using the following equations (2) and (3). V0 is the amount of main raw material 1 fed per unit time, V3 is the amount of composition adjuster 3 fed per unit time, VS is the total melting rate of the surface coating materials fed into the primary electric furnace 2 and secondary electric furnace 4, and V2 is the sum of the feed rates of the molten raw materials 1b from the secondary electric furnace 4 to the cotton mill 5. The units of V0, V3, VS, and V2 can be 1000 kg / Hr. C1M is the content of the target component M in the main raw material 1, C3M is the content of the target component M in the composition adjuster 3, CSM is the content of the target component M in the surface coating materials fed into the primary electric furnace 2 and secondary electric furnace 4, C2M is the content of the target component M in the molten raw materials supplied from the secondary electric furnace 4 to the cotton mill 5, and CNM is the correction amount of the target component M due to components N other than the target component M in the main raw material 1. C1M, C3M, CSM, and C2M are real numbers in the range of 0 to 1, and CNM is a real number in the range of -1 to 1. C1M×V0+C3M×V3+CSM×VS=(C2M+CNM)×V2 (2) V0+V3+VS=V2 (3)

[0036] In the above equations (2) and (3), if V2, calculated from the cotton-making efficiency U, is set as the condition for ensuring maximum productivity, then Vs is a constant that depends almost entirely on the temperature of the molten raw material 1b, and so the variables are V0 and V3. The control device 20 controls the amount V3 of the composition adjuster 3 added, and compares the required amount V0 of the main raw material 1 with the amount VA of molten blast furnace slag supplied from the blast furnace (composition adjustment process). If V0 is equal to or greater than V0, it is preferable to adjust it to V0; if V0 is insufficient, it is preferable to supplement the shortfall with dried, slowly cooled blast furnace slag or the like. This improves rock wool productivity.

[0037] As described above, when blast furnace slag or basalt is used as the main raw material 1, in order to set the acidity of the rock wool to a predetermined value, it is preferable to select one or more components selected from SiO2, CaO, Al2O3, and MgO as the target component M to be adjusted in the primary electric furnace 2. When the target component M to be adjusted is SiO2, it is preferable to correct the target value of SiO2 based on the composition of, for example, MgO as the other component N. [Example]

[0038] Example 1 Using the rock wool manufacturing equipment shown in the above embodiment, rock wool was manufactured using blast furnace slag with an SiO2 content C1M of 36.0% by mass and an MgO content of 5.0% by mass as the main raw material 1, and silica sand with an SiO2 content CSM of 99% by mass as the component adjuster 3 and surface coating material. The capacity W1 of the molten raw material in the primary electric furnace 2 was controlled to be approximately 40 t, and the capacity W2 of the molten raw material in the secondary electric furnace 4 was controlled to be 20 t. Two cotton mills 5 supplied the molten raw material from the secondary electric furnace 4, one to process PA where it was molded into plates, and the other to process PB where it was made into granular cotton.

[0039] The target SiO2 content supplied from the secondary electric furnace 2 to the cotton mill 5 was set to 42.0% by mass. Using the cotton milling efficiency U1 and yield r1 of the plate-forming process PA, and the cotton milling efficiency U2 and yield r2 of the granular cotton process PB, the supply rate V2 of the molten raw material 1b from the secondary electric furnace 4 to the cotton mill 5 was calculated as 13,700 kg / Hr from equation (1). The dissolution rate VS of the surface coating material was set to 300 kg / Hr based on past performance. The control device 20 calculated the required supply rate V0 of the main raw material 1 = 12,400 kg / Hr and the supply rate V3 of the composition adjuster 3 = 1,000 kg / Hr from equations (2) and (3) above, and controlled the output rate of the auxiliary raw material feed device 3a. Furthermore, because the supply of molten blast furnace slag from the blast furnace was insufficient, dried granulated slag was fed into the bubbling zone of the primary electric furnace 2 at a feed rate of 150 kg / hr. This made it possible to maintain high productivity without reducing cotton production efficiency and to produce high-quality rock wool. [Industrial Applicability]

[0040] The rock wool manufacturing equipment and manufacturing method of the present invention have two electric furnaces arranged in series, and the component adjuster added to the primary electric furnace is adjusted based on the operating conditions, so that high-quality rock wool can be manufactured without reducing productivity, making it industrially useful. [Explanation of symbols]

[0041] 100 Rock wool manufacturing equipment 1. Main raw material (blast furnace slag) 1a Charging pot 1b Molten raw materials 2 Primary electric furnace 2a electrode 2b Electric furnace cover 2c Surface coating material inlet 2d Gas Bubbling Lance 2e Main raw material input port 3 Auxiliary raw materials (component adjustment materials) 3a Auxiliary raw material cutting device 4 Secondary electric furnace 4a electrode 4b Electric furnace cover 4c Surface coating material input port 4d. Pouring port from primary electric furnace 5 Cotton spinner 6 wheels 7. Rock wool fiber 8 Cotton collection room 9 Rockwool cotton 10 Picker 11 Surface coating material loading device 20 Control device PD product processing process

Claims

1. a primary electric furnace in which the main raw material is heated to a predetermined temperature, and a component adjuster is added to adjust the composition to a predetermined composition, thereby producing a molten raw material for rock wool; a secondary electric furnace for maintaining the molten raw material continuously supplied from the primary electric furnace at a predetermined temperature; a coating material supply means for supplying a molten metal surface coating material to each of the primary electric furnace and the secondary electric furnace; a cotton mill for fiberizing the molten raw material continuously supplied from the secondary electric furnace; a control means for controlling the rate at which a component adjuster is added to the primary electric furnace; and The control means acquires the component composition of the main raw material, the component composition of the component adjuster, the component composition and dissolution rate of the molten metal surface coating material in the primary electric furnace and the secondary electric furnace, and the rock wool production efficiency and yield, and is configured to ensure that the component composition of the molten raw material supplied from the secondary electric furnace becomes the desired component composition.

2. The component to be adjusted in composition in the primary electric furnace is SiO ２ , CaO, Al ２ O ３ The rock wool manufacturing equipment according to claim 1, wherein the component is one or more selected from the group consisting of MgO and MgO.

3. The rock wool manufacturing equipment according to claim 2, wherein the control means is configured to correct the target composition of the target component based on the composition of components other than the target component among the component compositions of the main raw material.

4. The rock wool manufacturing facility according to any one of claims 1 to 3, wherein the main raw material is one or more selected from molten blast furnace slag, solidified blast furnace slag, and basalt.

5. a first heating step of supplying a main raw material to a primary electric furnace, adding a molten metal surface coating material, and then heating the molten material, and adding a composition adjuster to obtain a molten raw material having a predetermined composition; a second heating step of continuously supplying the molten raw material from the primary electric furnace to a secondary electric furnace, charging a molten metal surface coating material into the secondary electric furnace, and then maintaining the temperature; a fiberization step of continuously supplying the molten raw material from the secondary electric furnace to a cotton mill and fiberizing the molten raw material; a component adjusting step of acquiring the component composition of the main raw material, the component composition of the component adjusting material, the component composition and dissolution rate of the molten metal surface coating material in the primary electric furnace and the secondary electric furnace, and the cotton-making efficiency and yield of rock wool, and controlling the addition rate of the component adjusting material to be added to the primary electric furnace so that the component composition of the molten raw material supplied from the secondary electric furnace becomes a desired component composition; A method for producing rock wool, comprising:

6. In the component adjusting step, the component of the molten raw material to be adjusted is SiO ２ , CaO, Al ２ O ３ The method for producing rock wool according to claim 5, wherein the component is one or more selected from the group consisting of ammonium nitrate and MgO.

7. The method for producing rock wool according to claim 6, wherein in the component adjustment step, a target composition of the target component is corrected based on a composition of components other than the target component among the component compositions of the main raw material.

8. The method for producing rock wool according to any one of claims 5 to 7, wherein the main raw material is one or more selected from molten blast furnace slag, solidified blast furnace slag, and basalt.

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