RU2720840C1 - Method (embodiments) and device (embodiments) for production of continuous mineral fibre - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: group of inventions relates to methods of producing mineral fibre and devices for producing continuous mineral fibre. Method for production of continuous mineral fibre includes dosed supply of ground mineral raw material into cold crucible of high-frequency induction furnace, its melting with simultaneous homogenisation and degassing of rock melt and melt release from crucible into device for fibre formation. Deicing agent is applied on the fibre and wound on a bobbin. Melting of mineral raw material is performed in sectional cold crucible in crucible zone, not exceeding ¼H from surface of melt bath in crucible. Extraction of melt from crucible into device for formation of fibre is made in form of jet through hole in side section of crucible from bath zone of melt, located at depth from ⅓H to ¾H from surface of melt bath, with control of flow rate, by changing the outlet area and jet temperature by 250–600 °C above the crystallisation temperature of the melt. Correction of temperature of produced melt is performed by changing distance between outlet opening and lower branch of inductor. Melt level in the crucible is continuously monitored and controlled. Device for production of continuous mineral fibre comprises hopper with dispenser for supply of ground rock to cold crucible of high-frequency induction furnace, at that crucible is equipped with tap hole for discharge of molten rock, and a fibre forming device and a fibre receiving mechanism arranged under them. Flue to dispense the melt of the rock from the crucible is a through hole in the side section of the crucible, located at a depth from ⅓H to ¾H from the surface of the melt bath. In addition, it is equipped with automatic dispenser-regulator of rock melt output from crucible through tap hole. Besides, the device can additionally contain in the cold crucible bottom part an insert with a hole, which consists of refractory and heat-insulating materials. Refractory material of the insert is in contact with the melting of the crucible rock. Device is also equipped with a bottom tubular feeder installed by the upper end in the hole of the insert, and by the lower end - into the device for fibre formation.

EFFECT: technical result is intensification of process of obtaining homogeneous melts of mineral raw material.

28 cl, 7 dwg, 1 tbl

Description

The invention relates to the chemical technology of inorganic materials, in particular to the production of fibers from aluminosilicate rocks, and can be used in factories for the production of glass fiber and fiber from natural basalt.

A known method for the production of continuous fibers from basalt rocks and a device for its implementation [1]. The method consists in preheating the crushed basalt to temperatures of 250-400 ° C, loading the heated basalt into the melt of the bath of the melting furnace in the zone of maximum temperatures of 1450-2000 ° C of the flame of the loading burner, melting, degassing and homogenizing the melt is carried out at the melting site at low levels a melt of 5-70 mm with a subsequent increase in the level of the melt to 80-300 mm in the bathtub of the furnace.

The disadvantage of this method is the need to maintain high temperatures in the working space of the furnace for melting basalt and providing the required amorphous melt, which requires a large gas flow rate and reduces the life of the lining of the furnace. In the zone of high temperatures of the burner flame up to 2000 ° С, the melting site is intensively eroded, especially when there is a violation of the supply of basalt to the melting site in the zone of the burner flame.

A known installation for the manufacture of basalt fibers [2]. The patent implements a method for the production of continuous mineral fiber, including feeding the crushed rock into a crucible of a high-frequency induction furnace, melting it with simultaneous homogenization and degassing of the molten rock, transferring the melt from the crucible to the feeder, from which it enters the spinneret feeder, forming the fiber, applying a sizing agent and winding fiber onto a bobbin.

The installation comprises a hopper with a dispenser for feeding crushed rock into a crucible of a high-frequency induction furnace, while the crucible is equipped with a tap hole for dispensing molten rock into a feeder, at least one spinneret feeder mounted above the fiber receiving mechanism is installed in its lower part.

However, the known method and device do not provide for the possibility of regulating and maintaining the level of the melt in the working zone above the die feeders to ensure stable hydrostatic pressure of the basalt melt in the feeder.

A known method for producing continuous basalt fiber [3], comprising loading a portion of basalt in an induction furnace having a cold crucible, induction heating a portion of basalt to a temperature of at least 2500 ° C to form a homogeneous melt having a viscosity of less than 500 cP, cooling a homogeneous melt to a temperature below about 1500 ° C by passing the melt through a tray with water cooling, the formation of a continuous basalt fiber through a sleeve (die). The cold crucible induction furnace operates at a frequency of about 0.22 megahertz, 0.32 megahertz, 0.44 megahertz, or 1.76 megahertz.

The known method does not provide the ability to control the flow rate of the melt from the induction furnace depending on the level of the melt in the fiberising unit, which does not provide stable hydrostatic pressure of the melt in this unit and negatively affects the quality of the produced continuous fiber.

The disadvantage of this method is the formation of a continuous basalt fiber immediately after cooling a homogeneous melt to a temperature below about 1500 ° C by passing the melt through a tray with water cooling, which can lead to fiber breakage during its formation. On a water-cooled chute, the melt jet contacts one side of the cross-section with the surface of the chute or the skull, and the other side with air, as a result of which the temperature around the circle draining from the chute is different. The temperature gradient over the cross section of the melt jet supplied to the fiber forming unit does not provide the temperature uniformity of the melt in this block, can lead to different melt viscosities in the volume of the fiber forming unit and, as a result, to fiber breakage. In addition, according to the patent [3], basalt is melted in a cold crucible of an induction furnace only at four fixed frequencies with a nominal frequency value: 0.22 megahertz, 0.32 megahertz, 0.44 megahertz, or 1.76 megahertz with an allowable deviation from nominal value ± 10%, i.e. only for specific basalt compositions. The basalt of each specific composition has its own chemical and mineralogical composition, and a characteristic temperature dependence of electrical conductivity. The optimal melting modes of basalt and the parameters of the high-frequency power source during melting of basalt in a cold crucible of an induction furnace in these modes may not coincide with four fixed frequencies. The technological process of melting mineral raw materials, including basalt, in a cold crucible of an induction furnace includes three stages. The first stage is the preparation of the initial melt in a cold crucible from powdered basalt. The second stage is the addition of new portions of basalt to the crucible until the required melt volume in the crucible is reached. The third stage is the complete melting of basalt, and the establishment of an equilibrium state that can be maintained for a long time. The first and second stage is relevant to carry out, having the ability to change the frequency of the current from the maximum value to the optimum for a particular composition of mineral raw materials.

It is known to automatically maintain a constant level of melt in a glass melting vessel during the production of continuous glass fiber [4]. Automatic regulation is carried out by the autoloader of glass beads, which allows maintaining the level of the melt in the glass melting vessel.

The autoloader consists of a consumable hopper for glass balls, a dispenser, loading streams, a melt level height sensor installed in a glass melting vessel, and a level height adjuster. To automatically maintain the melt level in the glass melting vessel, prefabricated glass balls are necessary. The manufacture of glass balls requires significant costs for the melting of the constituents of the glass, obtaining a homogenized melt, molding the balls from the melt, as well as the energy consumption for melt the balls in a glass melting vessel.

A known method of controlling the level of the melt [5], in which a laser beam is directed to the surface of the melt and its reflection is obtained at the photodetector. The position in which the laser beam hits the photodetector depends on the level of the melt. The photodetector is connected with a system of continuous supply of raw materials to the crucible, which ensures the constancy of the melt level. The disadvantage of this method is the low accuracy of the measurement, due to the use of a signal from the surface of the melt coated with particles loaded into the crucible of mineral raw materials.

A number of patents use a video camera to control the level of the melt, which is sent to the surface of the melt and a reference point located outside the melt. Regulation is carried out by measuring the distance between them, which is analyzed using a computer.

There is a method of controlling the level of the melt [6], in which a "well" type heat shield is fixed above the melt surface with a slot on the flanging in the lower part, at such a distance from the melt that a slot (mark) is reflected on it. The camcorder is directed to the surface of the melt and the mark, receive an image on the computer display. Based on the different luminosities of the melt surface and the marks, the distance between them is determined by computer processing the resulting image. The calculated value is compared with the set and based on this comparison produce a control action.

The disadvantage of this method is the need to use an additional structural element - a heat shield with a label and its exact fixation at a given distance from the surface of the melt. Due to the particles of mineral raw materials continuously loaded into the crucible, as well as non-molten particles located on the surface of a constantly moving melt caused by electrodynamic forces and convection, the measurement accuracy is not high enough.

A known method and device for the production of continuous mineral fiber [7].

The method includes a dosed supply of ground mineral raw materials into a cold crucible of a high-frequency induction furnace, its melting with simultaneous homogenization and degassing of the rock melt, and the melt is dispensed from the crucible into a fiber forming device, after which a sizing agent is applied to the fiber and wound onto a bobbin. Rock melting in an induction furnace is carried out in the frequency range 0.05-2.0 MHz, in an oxidizing medium at a temperature from 1900 to 2200 ° C to a melt viscosity of less than 1 Pa⋅s with constant electrodynamic mixing of the melt. The melt is transferred from the crucible to the feeder with its simultaneous cooling from the surface of the melt bath in the crucible in the form of a continuous jet freely falling to the surface of the melt bath in the feeder, smoothly lowering the temperature of the jet over its cross section during the fall by 250-500 ° C above the crystallization temperature molten rock by dynamic mixing.

The device comprises a hopper with a dispenser for feeding crushed rock into a cold crucible of a high-frequency induction furnace, the crucible is equipped with a notch for issuing a molten rock, and located below them, a device for forming fibers and a mechanism for receiving fibers

The disadvantage of this method and device is the issuance of the melt from the crucible to the feeder, which is produced from the surface of the bath of the melt in the form of a continuous jet. The rock supplied to the crucible is in the solid phase, and due to the initial porosity, has a density lower than the density of the melt. A rock particle does not sink in the melt, but is held on its surface. Part of the particles of the rock may fall into the melt discharged from the crucible from the surface of the molten bath in the form of a continuous jet. The ingress of unmelted particles into the feeder and further into the spinneret feeder will lead to fiber breakage during its production.

The technical task and goal of the proposed inventions is to intensify the process of obtaining homogeneous melts of mineral raw materials, expanding the technological capabilities of the production of continuous mineral fiber with refractory inclusions, rocks with a high content of SiO ₂ and Al ₂ O ₃ , mineral modified raw materials containing high-temperature oxides and production from of these melts of high quality continuous mineral fiber with improved physical and mechanical characteristics, providing the possibility of complete automation of the technological process for producing continuous mineral fibers.

To solve this problem, the following options for the production of continuous mineral fiber.

METHOD, 1st option:

от поверхности ванны расплава в тигле, а выдачу расплава из тигля в устройство для формирования волокна, производят в виде струи через отверстие в боковой секции тигля из зоны ванны расплава, находящейся на глубине от

до

от поверхности ванны расплава (где Н - полная глубина ванны расплава в тигле), с регулированием дебита, путем изменения площади выпускного отверстия и с температурой струи на 250-600°С выше температуры кристаллизации расплава, причем, корректировку температуры выдаваемого расплава производят, изменяя расстояние между выпускным отверстием и нижней ветвью индуктора, при этом, непрерывно выполняют контроль и регулирование уровня расплава в тигле. Кроме того: устройство для формирования волокна, выполнено в виде, по меньшей мере, одного фильерного питателя; устройство для формирования волокна, выполнено в виде фидера, оборудованного, по меньшей мере, одним фильерным питателем; контроль и регулирование уровня расплава в тигле, осуществляют с помощью инфракрасной видеокамеры, одновременно фиксирующей положение поверхности расплава в тигле и положение торца витка индуктора, после чего путем компьютерной обработки полученного изображения, определяют расстояние между этими положениями, затем вычисленное значение сравнивают с регламентным значением и осуществляют управление дозированием количества минерального сырья подаваемого в единицу времени на поверхность ванны расплава в тигле, и управление параметрами работы высокочастотного источника питания, путем повышения или понижения активной мощности подводимой к индуктору; контроль и регулирование уровня расплава в тигле, выполняют путем измерения массы холодного тигля, с содержащимся в нем расплавом и не расплавившимся измельченным минеральным сырьем, затем вычисленное значение сравнивают с регламентным значением и осуществляют управление дозированием количества минерального сырья подаваемого в единицу времени на поверхность ванны расплава в тигле, и управление параметрами работы высокочастотного источника питания, путем повышения или понижения активной мощности подводимой к индуктору.in a method for producing a continuous mineral fiber, comprising a dosed supply of ground mineral raw materials into a cold crucible of a high-frequency induction furnace, its melting while homogenizing and degassing the rock melt, and dispensing the melt from the crucible into a fiber forming device, after which a sizing agent is applied to the fiber and wound onto bobbin, according to the invention, the melting of mineral raw materials is carried out in a sectional cold crucible in the crucible zone not exceeding

from the surface of the molten bath in the crucible, and the melt is dispensed from the crucible into the fiber forming device, produced as a jet through an opening in the side section of the crucible from the zone of the molten bath located at a depth from

before

from the surface of the melt bath (where H is the total depth of the melt bath in the crucible), with the flow rate controlled by changing the area of the outlet and with a jet temperature of 250-600 ° C above the crystallization temperature of the melt, moreover, the temperature of the produced melt is adjusted by changing the distance between the outlet and the lower branch of the inductor, while continuously monitoring and regulating the level of the melt in the crucible. In addition: a device for forming a fiber, made in the form of at least one spinneret feeder; a device for forming a fiber, made in the form of a feeder equipped with at least one die feeder; control and regulation of the level of the melt in the crucible is carried out using an infrared camera that simultaneously records the position of the surface of the melt in the crucible and the position of the end face of the inductor, after which the distance between these positions is determined by computer processing the image, then the calculated value is compared with the regulatory value and carried out controlling the dosing of the amount of mineral raw materials supplied per unit time to the surface of the melt pool in the crucible, and controlling the operating parameters of the high-frequency power source by increasing or decreasing the active power supplied to the inductor; control and regulation of the level of the melt in the crucible is carried out by measuring the mass of the cold crucible, with the melt contained in it and the molten mineral raw materials not melted, then the calculated value is compared with the regulatory value and the dosage of the mineral raw materials supplied per unit time to the surface of the melt bath is controlled crucible, and control the parameters of the high-frequency power source by increasing or decreasing the active power supplied to the inductor.

METHOD, 2nd option:

от поверхности ванны расплава в тигле, а выдачу расплава из тигля в устройство для формирования волокна, производят с температурой соответствующей среднему значению температурного интервала выработки волокна для данного минерального сырья, и осуществляют посредством трубчатого питателя через боковую секцию тигля и/или посредством трубчатого питателя с донным выпуском расплава. Кроме того: трубчатый питатель нагревают до температуры равной верхнему значению температурного интервала выработки волокна; трубчатый питатель нагревают до температуры превышающую на 200-300°С температуру кристаллизации расплава; уменьшение дебита выдачи расплава или полное прекращение выдачи расплава, осуществляют путем понижения мощности нагрева трубчатого питателя и его охлаждением газообразной средой; устройство для формирования волокна, выполнено в виде, по меньшей мере, одного фильерного питателя; устройство для формирования волокна, выполнено в виде фидера, оборудованного, по меньшей мере, одним фильерным питателем.in a method for producing a continuous mineral fiber, comprising a dosed supply of ground mineral raw materials into a cold crucible of a high-frequency induction furnace, its melting while homogenizing and degassing the rock melt, and dispensing the melt from the crucible into a fiber forming device, after which a sizing agent is applied to the fiber and wound onto bobbin, according to the invention, the melting of mineral raw materials is carried out in a sectional cold crucible in the crucible zone not exceeding

from the surface of the molten bath in the crucible, and the melt is dispensed from the crucible to the fiber forming device, they are produced with a temperature corresponding to the average value of the temperature range of fiber production for a given mineral raw material, and is carried out by means of a tubular feeder through the side section of the crucible and / or by means of a tubular feeder with a bottom the release of the melt. In addition: the tubular feeder is heated to a temperature equal to the upper value of the temperature range of fiber production; the tubular feeder is heated to a temperature exceeding 200-300 ° C melt crystallization temperature; reducing the flow rate of the melt issuance or the complete cessation of the issuance of the melt, is carried out by lowering the heating power of the tubular feeder and cooling it with a gaseous medium; a device for forming a fiber, made in the form of at least one spinneret feeder; a device for forming a fiber, made in the form of a feeder equipped with at least one die feeder.

The main feature of the method of direct high-frequency melting of mineral raw materials in a cold crucible is the direct heating of the material by the energy of a high-frequency field, the material itself being in a metal crucible cooled by water. As a result of this, the distribution of temperatures and viscosity in the melt has its maximums and minimums. The temperature distribution in the melt is an important technological parameter that has a great influence on the homogenization of the melt and the choice of the layer in the melt bath from which the melt is taken into the hole in the side section of the crucible and / or into the bottom tubular feeder. The inhomogeneity of the viscosity of the melt depends on the temperature distribution in the melt, which in turn determines the direction and intensity of flows in the melt volume and the conditions for the melt to be dispensed from the cold crucible for further processing. A temperature gradient is created in the volume of the melt in the cold crucible, both in radius and in depth of the melt. The region of maximum temperature in the zone of the inductor is in the form of a ring. In the same annular region, rather intensive mixing of the melt occurs, caused by the electromotive forces induced by the inductor in the melt and the convective motion of the melt. A decrease in the melt temperature is observed near the water-cooled walls of the crucible. The melt layer adjacent to the walls of the crucible contains particles of mineral raw materials that are in direct contact with the walls of the cold crucible and a layer of viscous melt. In the volume of the melt in the cold crucible, there is a decrease in the temperature of the melt along its depth, that is, the lower the melt layer from which it is released, the lower the melt temperature. When approaching the hole intended for the release of the melt from the crucible to the inductor, the temperature of the melt discharged through the hole in the crucible rises. The inductor of the induction furnace has a movement mechanism relative to the crucible in the vertical direction. This allows you to adjust the position of the outlet in the side section of the crucible, as well as the upper end of the tubular feeder installed in the bottom of the crucible and taking the melt, relative to the inductor, thereby regulating the temperature of the melt that is discharged into the side tubular feeder through the hole in the side section of the crucible and / or to a bottom tubular feeder installed in the bottom of the crucible.

The continuous and uniform supply of crushed mineral raw materials to the crucible on the surface of the melt having a temperature of 2000 ° C and above allows one to intensify the process of melting the particles of mineral raw materials, completely homogenize the melt, maintain a constant amount of melt in the crucible, and provide a constant flow rate of the melt with the required temperature through the hole in the side section of the crucible, and / or through the bottom tubular feeder passing through the bottom of the crucible. With the initially identical chemical and mineralogical composition of mineral raw materials, the viscosity of the melt practically depends only on its temperature.

The feed is in the solid phase, and due to the initial porosity, has a density less than the density of the melt. Particles of the supplied raw materials do not sink in the melt, but are held on its surface. In the zone of the inductor in the annular region of the melt, the melt is mixed quite intensively, caused by the electromotive forces induced (induced) by the inductor in the melt and by the convective movement of the melt.

When an electromagnetic wave is incident on the surface of an electrically conductive melt, currents are induced in the latter, which interact with the magnetic field of the inductor. As a result, a force is applied to each element of the volume of the melt through which the induced current flows, by which the melt moves. In a cold crucible, this causes extrusion of the melt along the axis of the crucible up and down, flowing to the edges on the surface of the melt and at the bottom of the inductor, and returning to the middle horizontal plane along the walls. In this region of intense movement of the melt, on its surface there are both particles of unmelted mineral raw materials and those newly supplied to the crucible. During electrodynamic circulation of the melt in the crucible, smaller particles of mineral raw materials are mixed with the melt, due to the forces of liquid friction, they are captured by it and move with the melt in the zone of the inductor. Larger particles can remain on the surface of the melt pool until their mass due to melting decreases so much that they begin to mix with the melt and move with it not only along the surface, but also in depth, in the area of the inductor. The issuance of a melt intended to produce continuous mineral fiber from this crucible zone is not advisable, since it can lead to the ingress of a non-homogenized melt containing non-molten particles into the die feeder, and, as a result, to fiber breakage during its generation.

где Н - полная глубина ванны расплава в холодном тигле. Ниже зоны расположения индуктора с увеличением глубины, температура расплава уменьшается, что обусловлено уменьшением эффективности нагрева слоев расплава, находящихся ниже индуктора, а также отводом тепла через водоохлаждаемые боковые стенки и дно тигля. Ниже зоны расположения индуктора увеличивается толщина гарнисажа на боковых секциях тигля. Увеличивается в этой зоне и толщина вязкого слоя расплава. Чем больше слой гарнисажа на боковых секциях тигля, тем сложней обеспечить выдачу расплава с требуемой вязкостью и температурой через отверстие в боковой стенке тигля. Из-за относительно низкой температуры в придонной части объема ванны расплава, большой величины гарнисажа на боковой стенке тигля и значительной толщины вязкого слоя расплава, обеспечивать выдачу струи расплава через отверстие в боковой секции тигля на глубине объема расплава ниже

также не целесообразно.The zone of the inductor, with intense movement of the melt, is located in the upper part of the melt bath in the crucible from the surface of the melt at a depth of

where H is the total depth of the molten bath in a cold crucible. Below the inductor’s location zone with increasing depth, the melt temperature decreases, which is caused by a decrease in the heating efficiency of the melt layers located below the inductor, as well as heat removal through water-cooled side walls and the bottom of the crucible. Below the inductor location zone, the thickness of the skull on the side sections of the crucible increases. The thickness of the viscous melt layer also increases in this zone. The larger the layer of the skull on the side sections of the crucible, the more difficult it is to provide a melt with the required viscosity and temperature through a hole in the side wall of the crucible. Due to the relatively low temperature in the bottom part of the volume of the melt bath, the large amount of skull on the side wall of the crucible and the significant thickness of the viscous layer of the melt, to ensure the issuance of a jet of melt through the hole in the side section of the crucible at a depth of the melt volume below

also not appropriate.

до

от поверхности ванны расплава, где Н - полная глубина ванны расплава в тигле. Расплав, выдаваемый через отверстие в боковой секции тигля, полностью гомогенизирован. Выдача расплава из тигля через отверстие, расположенное ниже индуктора, исключает попадание в этот расплав не расплавившихся частиц. Выдаваемый расплав полностью гомогенизирован. При увеличении расстояния между выпускным отверстием в боковой секции тигля и нижней ветвью индуктора температура струи расплава, выдаваемого из тигля, будет снижаться, а при приближении этого отверстия к индуктору - повышаться.The melt is dispensed through an opening in the side section of the crucible from the zone of the melt bath, located below the lower branch of the inductor, that is, below the melting zone of mineral raw materials and where there is no electrodynamic mixing of the melt. Such a molten bath zone is at a depth of

before

from the surface of the molten bath, where H is the total depth of the molten bath in the crucible. The melt discharged through an opening in the side section of the crucible is completely homogenized. The issuance of the melt from the crucible through the hole located below the inductor eliminates the ingress of not molten particles into this melt. The discharged melt is completely homogenized. With an increase in the distance between the outlet in the side section of the crucible and the lower branch of the inductor, the temperature of the jet of melt discharged from the crucible will decrease, and when this hole approaches the inductor, it will increase.

The change in the flow rate of the melt jet is carried out as follows: when the melt level in the feeder decreases below the permissible, at the same time, the area of the outlet in the side section of the crucible is automatically increased, the amount of charge supplied to the crucible per unit time is increased, and the active power at the inductor is increased; when the melt level in the feeder increases above the permissible, at the same time automatically reduce the area of the outlet in the side section of the crucible, reduce the amount of charge supplied to the crucible per unit time, reduce the active power at the inductor.

For the melting of mineral raw materials in a cold crucible of an induction furnace, single-coil, double-coil or multi-coil inductors are used, covering the crucible. Multi-turn inductors allow increasing the depth of the melt pool (and reducing the temperature gradient along its depth). Research and operation of equipment for melting rocks showed that in the production of basalt fiber it is more advisable to use double-coil inductors. The plane of the upper end of the lower coil of the inductor is set 10-15 mm below the surface of the molten bath in the crucible. The upper coil of the inductor is set 20-25 mm above the surface of the molten bath. When melting mineral raw materials in a cold crucible installed inside a two-turn or multi-turn inductor, there is a region in the side section of the crucible where the surface of the melt bath is opposite the gap between two adjacent turns of the inductor, and an infrared video camera is directed to this area to control the position of the surface of the melt bath relative to coil inductor. The plane of the end face of the coil, which is located opposite the surface of the molten bath, can be selected as a reference point to control the current position of the surface of the molten bath when melting mineral raw materials in a cold crucible of an induction furnace. Changing the position of the surface of the melt bath relative to the inductor leads to a mismatch of the system "high-frequency power source - crucible" and a change in the operating modes of the high-frequency power source with load. The load is the volume of the melt in the cold crucible. With a mismatch, the active power supplied to the melt decreases, the thermal stability of the melting is violated. In this case, the induced current in the melt is not sufficient to create a power capable of not only compensating for losses from the heating zone, but also providing melting of an additional volume of raw materials. The width of the vertical slot in the crucible section, where the lens of the infrared video camera is directed, is selected so that the melt is kept from flowing out by forces of “surface tension”. In the volume of the molten bath adjacent to the side sections of the cold crucible, there is a layer of viscous melt. In the zone of the inductor, the layer of viscous melt is usually 3-5 mm and depends on the chemical composition of the mineral raw materials and the operating mode of the high-frequency power source. In the controlled slot there is a vertical layer of the liquid phase of a low-viscosity melt or a solid phase of the melt with a temperature close to the temperature of the upper limit of crystallization of the melt. During the melting process, when the surface of the melt bath is lowered in the crucible, part of the vertical layer of the melt located in the slot, which is higher than the surface of the melt, does not contact the bath melt, and its temperature drops sharply due to cooling from the water-cooled sections. The temperature gradient in the controlled slot between the surface of the melt pool and above this level reaches several hundred degrees. By controlling the infrared video camera, the temperature, the position of the surface of the melt in the slot, and the temperature, the position of the plane of the upper end of the branch of the inductor, determine the position of the surface of the bath of the melt relative to the inductor. Comparing the obtained value of the surface of the melt pool with the desired value, a control action is performed on the metering mechanism to correct the amount of mineral raw materials supplied per unit time to the surface of the melt. A control action is also made on the parameters of the high-frequency power source to increase or decrease the active power supplied to the inductor in order to increase or decrease the power supplied to the melt from an alternating electromagnetic field.

When melting high temperature oxides in a cold crucible, it is recommended to use a single-coil inductor, in which the plane of the upper end of the inductor should always be above the surface of the molten bath, but not higher than half the height of the inductor.

To solve this problem, the following device options for the production of continuous mineral fiber are also offered.

DEVICE, 1st option:

до

от поверхности ванны расплава (где Н - полная глубина ванны расплава в тигле), а устройство дополнительно снабжено автоматическим дозатором-регулятором выдачи расплава породы из тигля через летку. Кроме того: автоматический дозатор-регулятор выполнен в виде водоохлаждаемой пробки, подвижной в горизонтальной и вертикальной плоскостях и установленной напротив летки, причем, пробка и боковая секция тигля изготовлены из одного и того же материала и электрически соединены между собой; индуктор индукционной печи, снабжен механизмом его перемещения в вертикальной плоскости относительно холодного тигля; боковая секция тигля дополнительно снабжена сквозной вертикальной щелью-прорезью шириной от 1 до 3 мм и длиной от 30 до 60 мм, расположенной на уровне витка индуктора, а устройство снабжено инфракрасной видеокамерой направленной на щель-прорезь и связанной с компьютером, который в свою очередь связан с дозирующим механизмом бункера и с высокочастотным источником питания индуктора; устройство снабжено инфракрасной видеокамерой направленной на зазор между соседними боковыми секциями холодного тигля и на торец индуктора, расположенный на одной вертикальной прямой с контролируемым зазором между соседними боковыми секциями холодного тигля, инфракрасная видеокамера связана с компьютером, который в свою очередь связан с дозирующим механизмом бункера и с высокочастотным источником питания индуктора; при использовании одновиткового индуктора, виток индуктора снабжен сквозной выемкой равной

где В - высота витка индуктора.in a device for the production of continuous mineral fiber containing a hopper with a dispenser for feeding crushed rock into a cold crucible of a high-frequency induction furnace, the crucible is equipped with a notch for the delivery of molten rock, and located below them, a fiber forming device and a fiber receiving mechanism, according to of the invention, a notch for the delivery of molten rock from the crucible, is a through hole in the side section of the crucible, located at a depth of

before

from the surface of the molten bath (where H is the total depth of the molten bath in the crucible), and the device is additionally equipped with an automatic dispenser-regulator for the delivery of the molten rock from the crucible through the notch. In addition: the automatic dispenser-regulator is made in the form of a water-cooled plug, movable in horizontal and vertical planes and installed opposite the taphole, moreover, the plug and the side section of the crucible are made of the same material and are electrically interconnected; the inductor of the induction furnace is equipped with a mechanism for moving it in a vertical plane relative to the cold crucible; the side section of the crucible is additionally equipped with a through vertical slot-slot with a width of 1 to 3 mm and a length of 30 to 60 mm located at the level of the inductor coil, and the device is equipped with an infrared video camera aimed at the slot-slot and connected to a computer, which in turn is connected with the dosing mechanism of the hopper and with a high-frequency power source of the inductor; the device is equipped with an infrared video camera aimed at the gap between adjacent side sections of the cold crucible and at the end of the inductor located on the same vertical line with a controlled gap between adjacent side sections of the cold crucible, the infrared video camera is connected to a computer, which in turn is connected to the metering mechanism of the hopper and high frequency inductor power supply; when using a single-turn inductor, the coil of the inductor is equipped with a through recess equal to

where B is the height of the coil of the inductor.

DEVICE, 2nd option:

до

от поверхности ванны расплава (где Н - полная глубина ванны расплава в тигле), а устройство дополнительно снабжено боковым трубчатым питателем установленным верхним концом в летку тигля с зазором от 0,5 до 1,5 мм, причем, зазор между леткой тигля и наружной поверхностью трубчатого питателя, заполнен гарнисажем расплава из той же горной породы, а нижний конец трубчатого питателя, состыкован с устройством для формирования волокна. Кроме того: между боковой секцией тигля с леткой для выдачи расплава породы и верхним концом трубчатого питателя, установлен переходник с отверстием, выполненный из высокотемпературного и неэлектропроводного материала, одним концом переходник состыкован с боковой секцией тигля, а другим, с верхним концом трубчатого питателя, создавая совместно с трубчатым питателем общий канал для выдачи расплава из тигля в устройство для формирования волокна; индуктор индукционной печи, снабжен механизмом его перемещения в вертикальной плоскости относительно холодного тигля; боковая секция тигля дополнительно снабжена сквозной вертикальной щелью-прорезью шириной от 1 до 3 мм и длиной от 30 до 60 мм, расположенной на уровне витка индуктора, а устройство снабжено инфракрасной видеокамерой направленной на щель-прорезь и связанной с компьютером, который в свою очередь связан с дозирующим механизмом бункера и с высокочастотным источником питания индуктора; устройство снабжено инфракрасной видеокамерой направленной на зазор между соседними боковыми секциями холодного тигля и на торец индуктора, расположенный на одной вертикальной прямой с контролируемым зазором между соседними боковыми секциями холодного тигля, инфракрасная видеокамера связана с компьютером, который в свою очередь связан с дозирующим механизмом бункера и с высокочастотным источником питания индуктора; при использовании одновиткового индуктора, виток индуктора снабжен сквозной выемкой равной

где В - высота витка индуктора.in a device for the production of continuous mineral fiber containing a hopper with a dispenser for feeding crushed rock into a cold crucible of a high-frequency induction furnace, the crucible is equipped with a notch for the delivery of molten rock, and located below them, a fiber forming device and a fiber receiving mechanism, according to of the invention, a notch for the delivery of molten rock from the crucible, is a through hole in the side section of the crucible, located at a depth of

before

from the surface of the molten bath (where H is the total depth of the molten bath in the crucible), and the device is additionally equipped with a lateral tubular feeder with an installed upper end in the crucible notch with a gap of 0.5 to 1.5 mm, moreover, the gap between the crucible notch and the outer surface a tubular feeder, filled with a skull of a melt from the same rock, and the lower end of the tubular feeder, docked with a device for forming fiber. In addition: between the side section of the crucible with the notch for the delivery of molten rock and the upper end of the tubular feeder, an adapter with an opening made of high-temperature and non-conductive material is installed, one end of the adapter is docked to the side section of the crucible, and the other, with the upper end of the tubular feeder, creating together with the tubular feeder, a common channel for dispensing the melt from the crucible to the fiber forming apparatus; the inductor of the induction furnace is equipped with a mechanism for moving it in a vertical plane relative to the cold crucible; the side section of the crucible is additionally equipped with a through vertical slot-slot with a width of 1 to 3 mm and a length of 30 to 60 mm located at the level of the inductor coil, and the device is equipped with an infrared video camera aimed at the slot-slot and connected to a computer, which in turn is connected with a hopper dosing mechanism and a high-frequency inductor power source; the device is equipped with an infrared video camera aimed at the gap between adjacent side sections of the cold crucible and at the end of the inductor located on the same vertical line with a controlled gap between adjacent side sections of the cold crucible, the infrared video camera is connected to a computer, which in turn is connected to the metering mechanism of the hopper and high frequency inductor power supply; when using a single-turn inductor, the coil of the inductor is equipped with a through recess equal to

where B is the height of the coil of the inductor.

DEVICE, 3rd option:

где В - высота витка индуктора.in a device for the production of continuous mineral fiber containing a hopper with a dispenser for feeding crushed rock into a cold crucible of a high-frequency induction furnace, configured to dispense molten rock, and located below them, a fiber forming apparatus and a fiber receiving mechanism according to the invention, bottom part of the cold crucible is equipped with a liner with an aperture, which consists of refractory and heat-insulating materials, the refractory material of the liner in contact with the molten rock of the crucible, and the device is additionally equipped with a bottom tubular feeder installed with an upper end into the liner hole and a lower end into the fiber forming device . In addition: the inductor of the induction furnace is equipped with a mechanism for moving it in a vertical plane relative to the cold crucible; the side section of the crucible is additionally equipped with a through vertical slot-slot with a width of 1 to 3 mm and a length of 30 to 60 mm located at the level of the inductor coil, and the device is equipped with an infrared video camera aimed at the slot-slot and connected to a computer, which in turn is connected with a hopper dosing mechanism and a high-frequency inductor power source; the device is equipped with an infrared video camera aimed at the gap between adjacent side sections of the cold crucible and at the end of the inductor located on one vertical line with a controlled gap between adjacent side sections of the cold crucible, the infrared video camera is connected to a computer, which in turn is connected to the hopper dosing mechanism and high frequency inductor power supply; when using a single-turn inductor, the coil of the inductor is equipped with a through recess equal to

where B is the height of the coil of the inductor.

The movement of the inductor relative to the crucible is carried out with the aim of issuing a melt from a cold crucible with an optimum temperature for fiber production. The movement of the inductor provides the ability to issue the melt from the layers having different temperatures, located at different distances from the inductor, that is, from the zone of intense heating of the melt. During the movement of the inductor relative to the crucible, the heating (melting of the raw material), the intensity of the feed and the speed of movement of the inductor must be agreed. The consistency criterion is a constant position of the melt level relative to the plane of the inductor. The movement of the inductor is carried out with periodic stops during which the temperature of the melt dispensed from the crucible is measured, the feed rate of the raw material is adjusted, and the active power supplied to the inductor by a high-frequency power source is changed. When the inductor moves upward relative to the crucible, the distance between the place where the melt is dispensed from the crucible and the plane of the inductor (melt zone with a maximum temperature located in the region of the inductor) increases. The temperature of the melt dispensed from the crucible is reduced. The amount of mineral raw materials supplied to the crucible and its melting exceeds the flow rate of the melt from the crucible. Therefore, the feed rate is reduced and the active power of the inductor is corrected. When the inductor moves relative to the crucible down, the temperature of the melt discharged from the crucible rises. At the same time, they reduce the supply of mineral raw materials to the crucible and adjust the active power supplied to the inductor by a high-frequency power source. When the temperature at which the melt is dispensed from the crucible reaches the optimum value, the amount of raw material supplied to the crucible and the rate at which the melt is dispensed from the crucible are equalized, bringing them into compliance with which the position of the melt level relative to the inductor plane does not change.

In the device, in order to control the level of the melt in the cold crucible, the side section of the crucible is equipped with a through vertical slit-slot with a width of 1 to 3 mm and a length of 30 to 60 mm located at the level of the inductor, and the device is equipped with an infrared video camera aimed at the slot-slot and connected to a computer, which in turn is connected to the metering mechanism of the hopper and a high-frequency power source of the inductor.

In the device, the infrared video camera is aimed at the gap between adjacent side sections of the cold crucible and at the end of the inductor, located on one vertical line with a controlled gap between the adjacent side sections of the cold crucible, the infrared video camera is connected to a computer, which in turn is connected to the metering mechanism of the hopper and high frequency inductor power supply.

The invention is illustrated graphically.

In FIG. 1 - shows a structural (structural) diagram of a device for implementing a method for the production of continuous mineral fiber;

in FIG. 2 - shows a structural diagram of changing the area of the outlet in the lateral section of the crucible with a dispenser-regulator in the form of a water-cooled plug;

in FIG. 3 and 4 - shows a variant of the structural diagram using a single-coil inductor for melting mineral raw materials;

in FIG. 5 shows a block diagram of the melt dispensing from a cold crucible by means of a side tubular feeder;

in FIG. 6 shows a block diagram of the melt dispensing from an opening in a side section of a cold crucible by means of a side tubular feeder to a spinneret feeder;

in FIG. 7 shows a block diagram of the melt dispensing from the bottom of a cold crucible to a bottom tubular feeder.

The method is implemented in the following device.

A device for implementing the continuous mineral fiber production method is shown in FIG. 1. The device comprises a hopper 1 mounted on a common frame structure (not shown), equipped with a metering mechanism 2. The hopper 1 with a metering mechanism 2 are arranged to feed pre-ground mineral raw materials, for example, rock - basalt into a cold (water-cooled) crucible 3 s bottom and basalt melt 4 5. The metering mechanism 2 provides a continuous and uniform supply of basalt 5 to the surface 6 of the melt bath 4. Basalt 5, continuously and uniformly supplied to the surface of the melt 4, is in the solid phase, and due to the presence of gas inclusions and fusible compounds, has a density lower than the density of the melt. Fractions (particles) of the feedstock do not sink in the melt, but are held on its surface. The crucible 3 is installed inside the coil of the inductor 7, which is electrically connected to the high-frequency power source 8. The inductor has a lower turn 9 and an upper turn 10. The lower turn 9 of the inductor 7 is set 10-15 mm below the surface 6 of the melt 4 in the crucible 3. The upper turn 10 of the inductor 7 by 20-25 mm is installed above the surface 6 of the melt 4. The crucible 3 consists of a bottom part (not marked by the position) and side sections 11 cooled by water. Between sections 11 there are gap-slits with a width of 1-3 mm, which prevent the closure of eddy currents. At least in one of the sections 11 of the crucible 3 there is a hole 12, which is designed to dispense the melt 4 from the crucible 3. The hole 12 is located below the lower turn 9 of the inductor 7. The jet of melt 13 continuously flowing from the hole 12 of the crucible 3 is directed to the receiving zone 14 of the feeder 15. The feeder 15 is structurally and functionally connected to the crucible 3. The level sensor 16 monitors the melt level in the working zone of the feeder 15. One or more die feeders 17 are built into the lower part of the feeder to generate basalt melt by mechanical drawing. Spinneret feeders 17 are installed with the possibility of feeding continuous fibers into fiber receiving devices, for example, sizing devices 18, designed to prevent gluing (sticking) of continuous elementary fibers together, and winding devices with bobbins 19. When the melt level in the feeder changes, it is more than acceptable or less than the permissible value, the level sensor 16 gives the corresponding signal to the control computer 20. The computer 20 according to the program gives a signal to the control mechanism 21, which, using the metering regulator in the form of a water-cooled plug 22, changes the area of the hole 12 in the side section 11 of the crucible 3, respectively, depending on the signal of the computer 20, increasing or decreasing the area of the hole 12. Changing the area of the hole 12 leads to a change in the flow rate of the jet 13 of the melt 4 flowing through the hole 12 and falling into the feeder 15. When changing the flow rate of the jet 13 from the crucible, the level of melt 4 in the crucible 3 will change. The surface 6 of the bath of melt 4 will gradually begin to rise or fall relative to the branches of the inductor 7, depending on the decrease or increase in the flow rate of the jet 13 from the crucible 3, caused by the adjustment of the area of the hole 12. The sensor for monitoring the level of the melt in the crucible 3 is an infrared video camera 23 installed horizontally from surface 6 of the bath of the melt 4, on the side of the crucible 3 and its lens 24 is directed to a vertical slot 25 of a width of 1-3 mm and a length of 30-60 mm, made in one of the sections 11 of the crucible and located between the lower 9 and upper 10 turns of the inductor 7. The image of the slot and the upper plane of the lower turn 9 are obtained on the display of the computer 20. Based on the different luminosities of the boundary of the surface of the melt 4 in the controlled vertical slot 25 and the upper end of the coil 9 of the inductor 7, the distance between them is determined by computer processing the resulting image. The calculated position of the melt level is compared with a predetermined (necessary) position of the level. Based on this comparison, a signal is sent to the computer 20, which produces a control action on the metering mechanism 2 to correct the amount of mineral raw materials continuously supplied per unit time to the surface of the melt 4. At the same time, the computer 20 is programmed to control the operation parameters of the high-frequency power supply 8 to change the active power supplied to the inductor 7. With an increase in the amount of mineral raw materials continuously supplied by the metering mechanism 2 to the crucible 3, the active power at the inductor 7 increases, and with a decrease in the amount of feed, it decreases.

Alternatively, in an apparatus for implementing a method for producing continuous mineral fiber, an infrared video camera 23 is mounted on the side of the sectional crucible 3, at the level of the plane of the upper end of the coil 9 of the inductor 7, and sent to the gap between adjacent side sections 11 and the upper end of the lower coil 9 of the inductor 7, located on one vertical line with a controlled gap between the two sections 11, and the position of the surface 6 of the melt pool 4 relative to the inductor is controlled by the computer 20. The computer, in turn, is connected with the metering mechanism 2 of the hopper 1 and with a high-frequency power source 8.

The melt in the form of a jet with a temperature of 250-600 ° C above the temperature of the upper crystallization limit is produced in the receiving zone 14 of the feeder 15, from which the melt flows to the production nodes, with die feeders 17, a fiber oiling device 18 and winding devices 19. The jet temperature 13, melt 4 discharged through opening 12 is selected 250-600 ° C. above the temperature of the upper crystallization limit and above the temperature of the upper fiber production interval. For rocks suitable for continuous fiber production, the temperature of the upper fiber production interval is 1370-1450 ° C. The temperature of the upper crystallization limit of these rocks, depending on the chemical and mineralogical composition, is in the range 1215–1315 ° С.

In FIG. 2 shows a sectional section A of FIG. 1, explaining the change in the area of the outlet in the side section of the crucible. The hole 12 in one of the side sections 11 of the crucible has, for example, a rectangular shape with two vertical semicircles. A water-cooled plug 22 with an end surface overlaps the upper part of the hole 12. In this case, the end surface of the plug 22 may not reach the outer plane of the side section 11 by 0.5 ... 3.5 mm. This gap allows you to save between the side wall of the section 11 and the end surface of the plug 22, a viscous melt layer that allows you to move the water-cooled plug 22 relative to the hole 12 with little effort, "without sticking", changing the area of the outlet in the side section, and thereby adjust flow rate of a melt jet from a crucible.

Alternatively, in FIG. 3 shows a device with a single-turn inductor for implementing the method of regulating the surface of the molten bath in a cold crucible of an induction furnace during the melting of mineral raw materials. Inductor 7 has one turn. The upper plane of the inductor is located above the surface 6 of the bath of the melt 4. In the coil of the inductor 7, opposite the controlled slot 25 in one section 11 of the crucible 3 (or the controlled gap between adjacent sections), where the lens 24 of the infrared video camera 23 is directed, a through cut (notch, recess) with a height (depth) of 1/3 V, where B is the height of the inductor (see Fig. 4). The infrared camcorder lens is aimed at this notch in the inductor. The image of the controlled slot in section 11 of crucible 3 (or the controlled gap between adjacent sections) in the through-cut area in the coil of inductor 7 is obtained on the display of computer 20. Based on the different luminosities of surface 6 of the bath of melt 4 in the controlled slot of section 11 of crucible 3 and the luminosity of the surface plane inductor 7 determine the distance between them by computer processing the resulting image. The calculated position of the melt level is compared with a predetermined (necessary) position of the level. Based on this comparison, a control action is performed on the dosing mechanism to correct the amount of mineral raw materials continuously supplied per unit time to the surface 6 of the melt pool 4 and a control action on the operation parameters of the high-frequency power supply 8 to change the active power supplied to the inductor 7.

An important step in obtaining high-quality fiber is the process of issuing a homogenized melt with the required parameters from the crucible and maintaining these parameters until the melt is fed to the openings of the spinneret feeder.

In FIG. 5 shows a block diagram of the melt dispensing from a cold crucible by means of a side tubular feeder.

A lateral tubular feeder 26 is installed in the hole 12 of the side section 11 of the crucible 3. A heating element 27 connected to a transformer (not shown) is installed around the outer surface of the side tubular feeder 26.

A tubular feeder 26 with a heating element 27 is located inside a heat-insulating casing 28, which has two fittings 29 and 30 for supplying a gas medium for cooling the tubular feeder 26. The tubular feeder can be made of metal, for example, platinum rhodium alloy, or of high-temperature ceramic, for example, zirconia . In the hole 12 of the side section 11 of the crucible 3, the side tubular feeder 26 is installed with a gap of 0.5-1.5 mm between the outer surface of the tubular feeder and the hole in the side section of the crucible. Structural elements for attaching the tubular feeder 26 to the side section 11 of the crucible 3 are not shown. The gap is filled with a skull 31 of melt 4 of the same mineral raw materials. The skull 31 between the outer surface of the tubular feeder 26 and the surface of the hole 12 of the section 11 is formed when the melt bath is induced in the crucible and with the appearance of the melt in the gap between the hole and the tubular feeder. The heating element 27 in the starting conditions is designed to heat the tubular feeder to a temperature at which the melt must be fed from the crucible 3, that is, to a temperature of 250-600 ° C above the temperature of the upper crystallization limit. During operation, the heating of the side tubular feeder 26 is carried out mainly due to heat transfer from the melt flowing from the crucible 3 through the channel of the tubular feeder, and the heating element 27 helps to maintain the required specific temperature of the outer surface of the tubular feeder. The temperature of the outer surface of the tubular feeder is fixed and this temperature is maintained within the required limits by a known method, for example, using thermocouples and a transformer automatic control system. The skull 31 of the melt in the gap of 0.5-1.5 mm between the outer surface of the tubular feeder 26 and the surface of the hole 12 in the side section 11 cooled by water provides sufficient thermal insulation so that the melt flowing through the side tubular feeder is practically not cooled in this location.

To stop the flow rate of the melt passing through the lateral tubular feeder 26, or to reduce the flow rate, lower the temperature of the heating element 27 by blowing the tubular feeder with a gaseous medium. A gaseous medium heated to a temperature equal to or lower than the crystallization temperature of the melt for forced cooling of the tubular feeder is supplied to one of the fittings 29 or 30 of the heat-insulating housing 28. This will lead to a decrease in the temperature of the melt flowing through the tubular feeder, to an increase in the viscosity of the melt near the inner walls of the tubular feeder, and as a result, to a decrease in the flow rate of the melt flowing through the tubular feeder, or to the termination of melt delivery through the tubular feeder. As a gaseous medium, for example, an inert gas or air can be used.

In FIG. 6 is a structural diagram of melt dispensing from an opening in a side section of a cold crucible by means of a side tubular feeder to a spinneret feeder.

In the hole 12 of the side section 11 of the crucible 3 is installed the upper end of the side tubular feeder 26 with a uniform gap of 0.5-1.5 mm between the outer surface of the tubular feeder and the hole 12 in the side section 11 of the crucible 3, and the lower end of the side tubular feeder 26 is joined with a spinneret feeder 17. A melt stream continuously flowing out of the opening 12 of the crucible 3 through the channel of the tubular feeder 26 flows into the spinneret feeder 17, designed to generate the melt into a continuous fiber by mechanical drawing. The die feeder 17 is installed with the possibility of feeding continuous fibers into a device for receiving fibers, for example, a sizing device 18, designed to prevent gluing (sticking) of elementary continuous fibers together, and a winding device with bobbins 19.

In FIG. 7 is a structural diagram of the melt dispensing into a bottom tubular feeder passing through the bottom of a cold crucible.

The device comprises a cold crucible 3 with a bottom part (position not highlighted) and with a melt 4. An insert 32 is installed in the bottom part of the crucible 3, consisting of a combination of refractory material, for example, chrome oxide, and heat-insulating material. The insert 32 has a through hole in which the upper end of the bottom tubular feeder 33 is inserted. The bottom tubular feeder 33 passes through a window 34 in the bottom of the crucible 3 and is joined to the spinneret 17 with its lower end.

Under conditions of local heating of the melt by the inductor, the volume of the melt pool is limited and easily adjustable. Induction heating with electrodynamic mixing allows you to get a deep bath with a fairly uniform distribution of temperature along the height from the zone of the inductor to its bottom layers. The maximum temperature is observed near the surface in the area of the inductor. With increasing melt depth, the temperature decreases due to heat removal through the walls of the crucible and a decrease in the intensity of heating due to the distance from the inductor. In the bottom part of the bath volume there is a melt crystallization zone. Due to the mechanism of movement of the inductor and the crucible in a vertical plane relative to each other during operation, the distance between the inductor 7 and the upper end of the bottom tubular feeder 33 is regulated, thereby changing the temperature of the melt 4 entering the bottom tubular feeder 33.

The degree of disclosure of devices and methods implemented therein for the production of continuous mineral fiber is sufficient to use the proposed inventions in industry with the achievement of the claimed technical result.

An example implementation of a method for the production of continuous mineral fiber.

The developed method for the production of continuous mineral fiber was implemented in a pilot plant consisting of a high-frequency generator, an induction furnace with a cold (water-cooled) crucible and inductor, a dosing mechanism, guides for water-cooled trays, an electrically heated feeder, a spindle feeder, and a thread winder.

Gabbro of the Maletinsky deposit in the Altai Territory was used as a rock for the manufacture of continuous mineral fiber. The chemical composition of gabbro:

SiO ₂ - 46.53%; Al ₂ O ₃ - 16.59; TiO ₂ - 2.18; FeO - 7.20; Fe ₂ O ₃ - 4.58; CaO - 10.41; MgO - 4.37; MnO - 0.17; P ₂ O ₅ - 0.28; K ₂ O - 2.44; Na ₂ O - 2.02.

For rock melting, a high-frequency generator VCHI11-60 / 1.76 (vibrational power 60 kW, operating frequency 1.76 MHz), a water-cooled sectional crucible with copper sections and a two-turn inductor were used. The diameter of the crucible is 230 mm, the area of the melt mirror is 0.04 m ² . Inside the water-cooled crucible, consisting of vertical sections isolated from each other, a molten bath is induced. The walls of the crucible are transparent to the electromagnetic field of the inductor, which concentrically covers the crucible, since the field penetrates into the crucible through the cracks between the sections. The size of the gap gaps is 1-1.5 mm The lower coil of the inductor with its upper surface of the coil is installed 12 mm below the surface of the melt bath induced in the crucible. The upper coil of the inductor is set at its lower surface 20 mm above the surface of the molten bath. The surface of the induced melt pool is located between two turns in the inductor and during the melting of the rock and the transfer of the melt from the crucible should be maintained at this level. The depth of the molten bath is 210 mm. The region of intense movement of the melt is located opposite the inductor zone and is approximately 50 mm deep from the surface of the melt.

In one of the sections of the crucible, there is a hole. The hole is located at a distance (depth) of 120 mm from the surface of the molten bath, below the lower coil of the inductor. The hole has the shape of a rectangle with two semicircles vertically. The area of the hole is 55 mm ² . This hole in the side section of the crucible can be completely or partially blocked by a water-cooled plug, which allows you to control the flow rate of the melt stream from the crucible, and also allows you to completely block it and stop the flow of the melt from the crucible. In one of the sections of the crucible, a vertical section is made 2.5 mm wide and 50 mm long. The cut is located between the lower and upper branches of the inductor.

The induction furnace of the pilot plant is equipped with a thermal imaging infrared system designed to measure the spatial distribution of the radiation temperature of objects by their own thermal radiation. The system consists of an infrared video camera FLIR A645sc in a protective casing with water cooling connected to a personal computer with an integrated control board. An infrared video camera is installed in the cabinet of the induction furnace opposite the vertical section in the crucible section at the level of the upper surface of the lower coil of the inductor. The principle of the system is based on measuring the difference in radiation temperature of the coil of the inductor cooled by running water and the melt visible above the bottom coil of the inductor in a vertical section of the section. The lower coil of the inductor and the melt are at different physical temperatures, which is why the emissivity of the melt as a material is much greater than the emissivity of the inductor metal cooled by running water. Measured radiation temperatures vary. Thermal radiation from the inductor and the melt through the optical system of the infrared video camera is transmitted to the receiver, which is a matrix (size 640 × 480 pixels) of infrared highly sensitive focal plane detectors (FPA). Further, the received signal is digitized and displayed on the screen of a personal computer through the electronic unit for measuring, recording and mathematical processing. Using special software installed on a personal computer and a control board, the system informs the operator about the position of the surface of the melt bath in the crucible relative to the inductor and, if necessary, gives signals (control action):

- to a metering mechanism for correcting the amount of raw material supplied per unit time to the surface of the melt in the crucible;

- on the parameters of the high-frequency power source to increase or decrease the active power supplied to the inductor.

The pilot installation works as follows.

Natural basalt with a fractional composition of up to 2.5 mm is continuously fed into a sectional cold crucible of an induction furnace. The feed is carried out from the hopper by a metering mechanism. The performance of the dispenser is set by the rotational speed of the motor controlled by the electric drive and can vary in the range from 5 to 150 kg / h. Under the influence of the transfer of thermal energy from the melt in the crucible, the basalt fractions melt. The temperature of the basalt melt in the cold crucible is maintained by the active power transmitted to the melt by means of an inductor connected to a high-frequency power source. In the mode of stabilization of rock melting, the flow rate of the melt stream continuously flowing out of the hole in the side section of the crucible is ensured by supplying the required amount of rock continuously supplied by the dispenser to the crucible. When the jet flows out of the crucible hole, the melt temperature is measured. To measure the temperature of the melt jet, an infrared thermometer Kelvin KB Dipol was used, which has a temperature measurement range of 800 ... 2200 ° C and a resolution of 1 ° C. The measured temperature of the melt jet is transmitted to the control computer. In the control computer there are parameters for the dependence of the viscosity of a particular rock on its temperature. Computer software calculates the viscosity of the melt jet and its flow rate.

The melt stream flowing out of the crucible hole is fed to the cooling trays and then flows into the receiving zone of the feeder. The feeder is made in the form of a special electrothermal device containing heating means in a thermally insulated casing - high-temperature resistance heaters designed for use in electric resistance furnaces with air temperatures up to 1800 ° C, connected to a transformer and having a control system. The feeder contains a receiving and working zone, equipped with means for monitoring the parameters of the melt (temperature sensors, level sensor). The melt level in the feeder is monitored using a level sensor. As a sensor of the melt level in the feeder, a ULM-11 non-contact radar level gauge is used, which provides continuous measurement of the melt level in the feeder. When the melt level in the feeder changes below or above the permissible level sensor sends a corresponding signal to the control computer. The control computer software allows you to process the data received from the level sensor and, based on these data, control the movement mechanism of the water cooling plug by changing the flow rate of the melt stream from the crucible hole, and control the dosing mechanism to correct the amount of rock continuously fed into the crucible unit of time. At the same time, the control computer provides the control action on the parameters of the high-frequency power source to change the active power supplied to the inductor.

For the formation of continuous fiber from a melt located in the working area of the feeder, a device for forming continuous fiber is used, consisting of a set of platinum rhodium feeders: tubular and spinneret with 200 holes. Extraction of a continuous mineral fiber and winding it onto bobbins after a sizing device is carried out by a NAS-3 winding machine.

As a result of work on the proposed method and device for the production of continuous mineral fiber in a pilot plant from the rock (gabbro) of the Maletinskoe deposit, fiber was obtained with the characteristics presented in the table:

Sources of patent technical information:

1. RF patent 2421408 of 11/23/2009

2. RF patent for utility model No. 162546 of 05/15/2015.

3. US patent 9771294 from 09/26/2017.

4. Continuous glass fiber. Fundamentals of technology and properties. Edited by M.G. Chernyak. M., publishing house Chemistry, 1965, pp. 131-136, fig. 59.

5. German patent 3904858, MKI C30B 15/20.

6. German patent 4231162 C2, MKI C30B 15/26.

7. The decision to grant a patent for an invention according to the application No. 2018142737/03 (069479). Application submission date 26.11.2018.

Claims (28)

1. A method for the production of continuous mineral fiber, comprising a metered supply of ground mineral raw materials into a cold crucible of a high-frequency induction furnace, its melting with simultaneous homogenization and degassing of the molten rock and the transfer of the melt from the crucible to the fiber forming device, after which a sizing agent is applied to the fiber and wound onto bobbin, characterized in that the melting of mineral raw materials is carried out in a sectional cold crucible in the crucible zone, not exceeding

from the surface of the molten bath in the crucible, and the melt is dispensed from the crucible to the fiber forming device in the form of a jet through a hole in the side section of the crucible from the zone of the molten bath located at a depth from

before

from the surface of the melt bath (where H is the total depth of the melt bath in the crucible), with the flow rate controlled by changing the area of the outlet and with a jet temperature of 250-600 ° C higher than the crystallization temperature of the melt, and the temperature of the produced melt is adjusted by changing the distance between the outlet hole and the lower branch of the inductor, while continuously monitor and control the level of the melt in the crucible. 2. The method according to p. 1, characterized in that the device for forming the fiber is made in the form of at least one spinneret feeder. 3. The method according to p. 1, characterized in that the device for forming the fiber is made in the form of a feeder equipped with at least one die feeder. 4. The method according to p. 1, characterized in that the control and regulation of the level of the melt in the crucible is carried out using an infrared camera, simultaneously fixing the position of the surface of the melt in the crucible and the position of the end face of the inductor, after which the distance between these positions is determined by computer processing the resulting image. , then the calculated value is compared with the regulatory value and control the dosing of the amount of mineral raw materials supplied per unit time to the surface of the melt pool in the crucible, and control the operation parameters of the high-frequency power source by increasing or decreasing the active power supplied to the inductor. 5. The method according to p. 1, characterized in that the control and regulation of the level of the melt in the crucible is performed by measuring the mass of the cold crucible with the melt contained in it and the molten mineral raw materials not melted, then the calculated value is compared with the regulatory value and the dosage of the mineral raw material is controlled supplied per unit time to the surface of the molten bath in the crucible, and controlling the operation parameters of the high-frequency power source by increasing or decreasing the active power supplied to the inductor. 6. A method of producing continuous mineral fiber, comprising a dosed supply of ground mineral raw materials into a cold crucible of a high-frequency induction furnace, its melting with simultaneous homogenization and degassing of the molten rock and the transfer of the melt from the crucible to the fiber forming device, after which a sizing agent is applied to the fiber and wound onto bobbin, characterized in that the melting of mineral raw materials is carried out in a sectional cold crucible in the crucible zone, not exceeding

from the surface of the melt bath in the crucible, and the melt is dispensed from the crucible to the fiber forming device at a temperature corresponding to the average value of the temperature range of fiber production for a given mineral raw material, and is carried out by means of a tubular feeder through the side section of the crucible and / or by means of a tubular feeder with a bottom the release of the melt. 7. The method according to p. 6, characterized in that the tubular feeder is heated to a temperature equal to the upper value of the temperature range of fiber production. 8. The method according to p. 6, characterized in that the tubular feeder is heated to a temperature that is 200-300 ° C higher than the crystallization temperature of the melt. 9. The method according to p. 7 or 8, characterized in that the decrease in the flow rate of the melt issuance or the complete cessation of the melt issuance is carried out by lowering the heating power of the tubular feeder and its cooling with a gaseous medium. 10. The method according to p. 6, characterized in that the device for forming the fiber is made in the form of at least one spinneret feeder. 11. The method according to p. 6, characterized in that the device for forming the fiber is made in the form of a feeder equipped with at least one die feeder. 12. A device for the production of continuous mineral fiber containing a hopper with a dispenser for feeding crushed rock into a cold crucible of a high-frequency induction furnace, the crucible is equipped with a notch for issuing a molten rock, and an apparatus for forming a fiber and a mechanism for receiving fibers located below them, the fact that the notch for the delivery of molten rock from the crucible is a through hole in the side section of the crucible, located at a depth of

before

from the surface of the molten bath (where H is the total depth of the molten bath in the crucible), and the device is additionally equipped with an automatic dispenser-regulator for the delivery of the molten rock from the crucible through the notch. 13. The device according to p. 12, characterized in that the automatic dispenser-controller is made in the form of a water-cooled plug, movable in horizontal and vertical planes and installed opposite the notch, and the plug and side section of the crucible are made of the same material and are electrically connected between by myself. 14. The device according to p. 12, characterized in that the inductor of the induction furnace is equipped with a mechanism for moving it in a vertical plane relative to the cold crucible. 15. The device according to p. 12, characterized in that the side section of the crucible is additionally equipped with a through vertical slot-slot with a width of 1 to 3 mm and a length of 30 to 60 mm, located at the level of the coil of the inductor, and the device is equipped with an infrared video camera aimed at a slot-slot and connected to a computer, which, in turn, is connected with the metering mechanism of the hopper and with a high-frequency power source of the inductor. 16. The device according to p. 12, characterized in that the device is equipped with an infrared video camera aimed at the gap between adjacent side sections of the cold crucible and at the end of the inductor located on the same vertical line with a controlled gap between adjacent side sections of the cold crucible, the infrared video camera is connected with a computer, which, in turn, is connected with the metering mechanism of the hopper and with a high-frequency power source of the inductor. 17. The device according to p. 12, characterized in that when using a single-turn inductor, the coil of the inductor is equipped with a through recess equal to

where B is the height of the coil of the inductor. 18. A device for the production of continuous mineral fiber containing a hopper with a dispenser for feeding crushed rock into a cold crucible of a high-frequency induction furnace, the crucible is equipped with a notch for issuing a molten rock, and a fiber forming apparatus and a fiber receiving mechanism located below them, characterized the fact that the notch for the delivery of molten rock from the crucible is a through hole in the side section of the crucible, located at a depth of

before

from the surface of the molten bath (where H is the total depth of the molten bath in the crucible), and the device is additionally equipped with a lateral tubular feeder installed with its upper end in the crucible’s notch with a gap of 0.5 to 1.5 mm, the gap between the crucible’s notch and the outer surface the tubular feeder is filled with a skull of a melt from the same rock, and the lower end of the tubular feeder is docked with a device for forming fiber. 19. The device according to p. 18, characterized in that between the side section of the crucible with the tap hole for issuing the molten rock and the upper end of the tubular feeder there is an adapter with an opening made of high-temperature and non-conductive material, one end of the adapter is docked with the side section of the crucible, and the other - with the upper end of the tubular feeder, creating, together with the tubular feeder, a common channel for dispensing the melt from the crucible to the fiber forming apparatus. 20. The device according to p. 18, characterized in that the inductor of the induction furnace is equipped with a mechanism for moving it in a vertical plane relative to the cold crucible. 21. The device according to p. 18, characterized in that the side section of the crucible is additionally equipped with a through vertical slot-slot with a width of 1 to 3 mm and a length of 30 to 60 mm, located at the level of the inductor, and the device is equipped with an infrared video camera aimed at a slot-slot and connected to a computer, which, in turn, is connected with the metering mechanism of the hopper and with a high-frequency power source of the inductor. 22. The device according to p. 18, characterized in that the device is equipped with an infrared video camera aimed at the gap between adjacent side sections of the cold crucible and at the end of the inductor located on one vertical line with a controlled gap between the adjacent side sections of the cold crucible, the infrared video camera is connected with a computer, which, in turn, is connected with the metering mechanism of the hopper and with a high-frequency power source of the inductor. 23. The device according to p. 18, characterized in that when using a single-turn inductor, the coil of the inductor is equipped with a through recess equal to

where B is the height of the coil of the inductor. 24. A device for the production of continuous mineral fiber containing a hopper with a dispenser for feeding crushed rock into a cold crucible of a high-frequency induction furnace, configured to issue a molten rock, and located below them a device for forming fiber and a mechanism for receiving fibers, characterized in that the bottom part of the cold crucible is equipped with a liner with an aperture, which consists of refractory and heat-insulating materials, the refractory material of the liner in contact with the molten crucible rock, and the device is additionally equipped with a bottom tubular feeder installed with an upper end into the liner opening and a lower end into the device for forming fiber. 25. The device according to p. 24, characterized in that the inductor of the induction furnace is equipped with a mechanism for moving it in a vertical plane relative to the cold crucible. 26. The device according to p. 24, characterized in that the side section of the crucible is additionally equipped with a through vertical slot-slot with a width of 1 to 3 mm and a length of 30 to 60 mm, located at the level of the coil of the inductor, and the device is equipped with an infrared video camera aimed at a slot-slot and connected to a computer, which, in turn, is connected with the metering mechanism of the hopper and with a high-frequency power source of the inductor. 27. The device according to p. 24, characterized in that the device is equipped with an infrared video camera aimed at the gap between adjacent side sections of the cold crucible and at the end of the inductor located on the same vertical line with a controlled gap between adjacent side sections of the cold crucible, the infrared video camera is connected with a computer, which, in turn, is connected with the metering mechanism of the hopper and with a high-frequency power source of the inductor. 28. The device according to p. 24, characterized in that when using a single-turn inductor, the coil of the inductor is equipped with a through recess equal to

where B is the height of the coil of the inductor.

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