RU2297396C1 - Method of production of the melt from the rocks and the melt from the scrap of the mineral wool production and the device for the method realization - Google Patents

Abstract

FIELD: mining industry; building materials industry; methods and devices of production of the melt from the rocks the melt from the scrap of the mineral wool production.

SUBSTANCE: the invention is pertaining to the technology of production of the melt by the bath-free smelting method from the rocks and from the scrap of the mineral wool production and may be used at manufacture of the fibrous warmth-keeping products for the civil and industrial building. The method of the rocks bath-free smelting and the mineral wool production scrap bath-free smelting in the gas furnace on the sloped hearth to provides for the thin-layer loading the charge on the heat spots with the temperature of 1700±250°C, formed by the shock-jet heating at the impact velocity of the gas fire jet with the hearth of 30-250 m\s with the continuous gravitational melt withdrawal for production. At that on the sloped hearth of the furnace they form the constant volume of the charge composed of the smelt part - the charge heap made in the form of the truncated cone, the greater base of which is located on the sloped hearth on the part made in the form of the charge column, the lower part of which is conjugated with the smaller base of the truncated cone. The charge smelting is exercised, when 1/3-d of the area of the heat spots is located inside the perimeter of the greater base of the truncated cone. The device for realization of the given method contains the vertical water-cooling shaft mounted above one of the charge loading tuyeres, and in which there is the loading groove installed coaxially to the walls of the shaft. The technical result of the invention is the increased efficiency of the method and also expansion of the technological possibilities due to involvement in the production of the mineral wool scrap.

EFFECT: the invention ensures the increased efficiency of the method, expansion of the technological possibilities, due to involvement into the production of the mineral wool scrap.

12 cl, 6 dwg, 2 ex

Description

FIELD OF THE INVENTION

The invention relates to a technology for producing a melt by a channelless method from rocks and mineral wool production waste, in particular to melting a charge on a pitched hearth with cumulus loading into a furnace, and can be used in the manufacture of fibrous heaters for civil and industrial construction.

State of the art

The existing methods of cumulative loading of the charge into storage-consumable baths during the production of silicate melts do not allow intensifying the melting process, since the formation of charge heaps is carried out by side loaders "under the wall" of the melting pool and more than half of the heat-absorbing surface of the charge heaps is closed from radiation and convective heating (see. Thin-layer glass melting. Glass technology under the editorship of II Kitaigorodsky, M., 1967, pp. 105-108).

At the same time, cumulus loading solves the problem of continuous and timely supply of the charge under the torch torch. Known technical solutions for a more rational method of forming charge heaps with circular heating by gas burners. In the invention, in accordance with the copyright certificate SU 1101426, a charge pile is formed in the middle of the melting pool by forcing the charge with a screw loader from the bottom of the furnace through a water-cooled mouthpiece built into the bottom. In this case, the base of the charge pile is under the melt. In order to avoid burden transfer to the pool mirror when the heap slopes collapse around the heap base, a labyrinth fence was made of refractories with the melt exiting to the side opposite to the production duct.

In another known invention (SU 1033421), a charge pile is formed in the middle of the pool by filling the charge through the arch of the melting furnace using a vertical cylindrical shaft. In this case, the charge pile is a regular truncated cone, the upper base of which serves as a support for the charge located in the loading shaft. Along the perimeter of the lower base of the charge pile, under the melt, bubbler heads are installed for supplying compressed air. The melt flowing down the slope of the charge pile captures with it small particles of the charge, dragging them into the bubble zone of the superheated melt, and contributes to their more rapid melting.

Another invention is known (SU 579234) with loading a melting pool through a furnace arch. The device includes a melting storage bath with gas burners, a chimney and a charge loader in the form of a metal shaft, as in SU 1033421, and the shaft in the roof of the furnace is made with the possibility of vertical movement from the electric drive.

A common disadvantage of the described known technical solutions is the removal of the molten mixture into the working duct.

The closest in technical essence and the achieved effect to the proposed invention is a method of melting rocks, including loading and melting the mixture on a solid base with continuous gravitational selection of the resulting melt for production, while the melting of the mixture is carried out on heat spots that form using directional shock jet heating at a collision speed of a gas plume with a hearth of 30 ... 250 m / s and a temperature of 1700 ± 250 ° C, moreover, the charge on the flame spots is dosed with a thin layer and / or in the form of lumpy rash. The device for implementing the method comprises a gas furnace with a ceramic pitched hearth, including a water-cooled lined arch, welded from sheet steel, with technological lances for installing high-speed burners, temperature sensors and charge loading, a drain tray for dispensing melt (RU 2230709). Heat spots in both the known and the proposed inventions are understood as local areas of the hearth overheated to the indicated temperatures, which are observed visually.

A disadvantage of the known invention is the erosion of the pitched hearth by a high-temperature high-speed torch in case of violations in the supply of the charge to the heat spots of the melting zone.

Disclosure of invention

The objective of the invention is to eliminate all the inherent disadvantages of the known methods, increasing the productivity of the method, as well as expanding technological capabilities.

The problem is solved by the method of gangless melting of rocks and mineral wool waste in a gas furnace on a pitched hearth, including a thin-layer charge loading onto heat spots with a temperature of 1700 ± 250 ° C, formed by shock-jet heating at a gas torch impact rate of 30 ... 250 m / s with continuous gravity selection of the melt for production, according to which a constant volume of the charge is formed on the pitched hearth of the furnace, consisting of a melted part - the charge pile in the form of a truncated cone, the larger base of which is located on the sloping hearth, and the feeding part in the form of a charge column, the lower part of which is associated with a smaller base of the truncated cone, while the charge is melted provided that fire spots are placed along the perimeter of the larger base of the truncated cone with a self-regulating replenishment of the lost part of the cone due to subsidence of the charge column under its own weight.

In private embodiments of the invention, the task is solved in that the melting of the charge is carried out by placing at least 1/3 of the area of the fire spots inside the perimeter of the larger base of the truncated cone.

It is advisable to load on the hot spots continuously by shedding the mixture from the slopes of the lost part of the cone.

It is desirable that the amount of charge in the charge column provides at least one hour of uninterrupted melt delivery in the absence of loading.

In some embodiments of the invention, it is advisable to form a constant volume of the charge with feed charge column close to the wall of the gas furnace.

If mineral wool waste is used in the method, then before being loaded into the furnace they are subjected to hugging and / or crushing, for example, on wheeled runners.

The problem is also solved by a device for the saltless melting of rocks and mineral wool production waste, including a gas furnace with a ceramic pitched hearth, a water-cooled lined arch made of sheet steel and equipped with technological lances for installing gas burners, temperature sensors and charge loading, a drain tray for dispensing a melt, according to which, at least one of the tuyeres for loading the charge is installed using a connecting flange vertical water a cooled shaft, moreover, in the shaft coaxially to the walls, a loading barrel made of heat-resistant material is installed with the possibility of movement.

In private embodiments of the invention, the problem is solved in that at least a portion of the loading barrel is made of siliconized graphite.

The loading barrel can be equipped with a vibration exciter for the descent of the charge.

An additional charge distributor in the form of a massive cone-shaped body made of highly refractory material can be additionally installed on the pitched hearth under the loading shaft.

At least one remote non-contact temperature meter oriented to heat spots can be installed above the tuyeres for temperature sensors, which can be installed as an infrared thermometer.

Brief Description of the Drawings

Figure 1 shows a General view of the device.

Figure 2 shows the location of the flame spots with a unilateral slope of the charge pile adjacent to the wall of the furnace.

Figure 3 shows the correction scheme of the melting zone by changing the angle of inclination of the melting burners.

Figure 4 shows the correction scheme of the melting zone by changing the area of the base of the charge pile.

Figure 5 shows a variant of the device using the layout of the charge in the form of a conical body.

Figure 6 shows a variant of the device using the layout of the charge in the form of a complex cone-shaped body.

Positions in the drawings and diagrams mean the following.

1. Oven

2. Pitched hearth

3. Drain tray

4. Water-cooled arch

5. Technological lance

6. Lightweight refractory

7. Gas burner for melting the charge

8. Gas burner for shielding the melt

9. Water cooled mine

10. Flange connection

11. Boot barrel

12. The layout of the charge

13. The charge pile

14. The charge column

15. Fire stain

16. Infrared thermometer

The implementation of the invention

A device for implementing the proposed method is a melting bezvanny furnace (1), which includes a ceramic heat-resistant pitched hearth (2), a drain tray (3), a hollow, water-cooled arch welded from sheet steel (4), equipped with technological tuyeres (5), a arch (4) lined with lightweight refractory (6), a power frame (not shown) and other structural rigidity elements are placed both on the outer and inner sides of the vault cavity (4). In the technological tuyeres (5) of the roof (4), high-speed gas burners are installed for melting the charge (7) and for heat shielding (8) of the drain pan (3) and at least one vertical water-cooled shaft (9), paired with the roof ( 4) flange connection (10), in the shaft (9) coaxially to the walls there is a loading barrel (11) with the possibility of vertical movement from a special drive (not shown). Under the mouth of the loading shaft (11), an additional spreader (12) is installed on the pitched hearth (2) to form a thin charge layer. The spreader (12) has a conical shape (see Fig. 5), or a complex conical shape - it is made in the form of a cone turning into a flat base (see Fig. 6) and is made of a heat-abrasion-resistant material, for example, chromium-aluminum-zirconium composition. Execution of the cone-shaped distributor stimulates the gathering of the charge and its location on the bottom in the form of a thin layer, while the cone-shaped part of the distributor interacts with the mouth of the loading shaft when the charge is converging, and the flat base with gas torches.

On the loading shaft (11) of the shaft (9), a stimulator for the descent of the charge of vibrational or shock action (not shown) is installed.

The invention is as follows.

Example 1

In the furnace (1) for the vannonless melting of the charge, made according to the invention, load the basalt charge with a fractional composition of 2 ... 30 mm. The loading is carried out through the loading barrel (11) of the water-cooled shaft (9), while the barrel (11) is pre-lowered into the furnace until it stops in a pitched hearth (2). The barrel (11) is filled with a charge and slowly returned to the shaft (9) using a lifting device, leaving a pile pile (13) in the form of a cone on a sloping hearth (2) - a support for the charge column (14). According to the invention, the perimeter of the lower base of the support cone of the charge pile (13) should not go beyond the limits of the melting zone, conditionally determined by the projections of the flights of the melting gas burners (7) on the pitched hearth (2) - heat spots (15) (see figure 2). After returning to the shaft (9), the loading shaft (11) is fixed in place and the position found is not changed while the charge is used with a given angle of repose. The loss of charge in the loading shaft (11) spent on the formation of the support cone is made up from the consumable cube (not shown) after installing it over the loading shaft. On this, the operation of forming a self-regulating charge system for the charge of the melting zone is completed.

As an embodiment of the proposed method, the charge column (14) and the support cone (13) are formed close to the wall of the furnace with a slope (Fig. 1).

After the self-feeding system is formed, they start heating and hatching the furnace, include melting burners (7), as well as shielding and overheating (8) with a gradual increase in their thermal power.

The shedding of the slopes as the base of the sacrificial cone is melted in the proposed invention is the basic principle of thin-layer loading and melting of the charge on heat spots.

The optimum melting mode is achieved by placing at least 1/3 of the area of the flame spots inside the perimeter of the base of the charge pile. It has been experimentally established that when the area of flame spots is less than 1/3, the rate of smelting of the base of the expendable cone is minimal.

Correction of the melting zone in this case can be achieved by changing the angle of inclination of the melting burners (figure 3). The first sign of the started melting of the charge is a thin-jet intermittent outflow of the melt from the production drain pan (3) in the hearth (2). As the furnace warms up, the fullness of the jet increases, the melt is formed into a stable monostroy, reaching a maximum. The higher the thermal stress in the melting zone, the higher the melt yield. If it is necessary to obtain a melt with maximum overheating without changing the flow rate, they do this by increasing the power of the shielding burners (8), without changing the thermal regime of the melting burners (7).

According to the invention, the area of the lower base of the support cone of the charge column can, within certain limits, be adjusted (decreasing or increasing) by raising and lowering the loading barrel using a jack mechanism (see Fig. 4).

To avoid overheating and / or slagging of the mouth of the boot shaft, fan air is supplied to the shaft.

To ensure the timely arrival of the mixture onto the hot spots, the loading barrel (11) from above is constantly fed from a replaceable tube (not shown) with a capacity designed for three to four hours of operation of the furnace in the optimal mode of melt delivery.

At angles of repose of less than 45, uncontrolled avalanche descents of the mixture to heat spots are possible. To avoid this, a thin-layer layout of the charge is proposed when loading the charge (12) installed on the bottom (2) under the loading barrel (11) and made in the form of a massive body with constant or variable taper, smoothly turning into a flat base. In this case, the conical part of the spreader (12) interacts with the mouth of the loading barrel (11), and the base interacts with the torches of gas burners (7). To monitor the thermal voltage of the melting zone above the arched tuyeres, remote infrared thermometers (16) focused on heat spots (15), in particular Kelvin KB Dipol pyrometers developed by the Technological Center for Unique Instrumentation of the Russian Academy of Sciences, were installed for temperature measurement.

In the technology of waveless melting of the charge, high-speed burners with a high-temperature shock-jet torch are used. The principle of burning gas in these burners eliminates (unnecessarily) the content of carbon monoxide in the combustion products, which, in turn, allows the use of spent heat in the process, for example, for an open basement or drying.

The loading method of the furnace “charge column” expands the possibilities of melting without melting on the pitched hearth, in particular, solves the problem of protecting the pitched hearth from erosion and burning through the proposed self-regulating supply of the charge to the fire spots.

The formation of the charge column "under the wall" should be considered as an option to protect the base of the walls of the melting zone.

Example 2

Mineral wool waste smelting

The production of mineral wool and products based on it is an independent large-capacity technology. To obtain melt and fiber in mineral wool production, high-performance coke ovens are used - cupola furnaces with a debit of up to 4.0 tons / hour, and multi-roll centrifuges. At the same time, the design and regulatory loss of the melt during processing into fiber is 25%. In practice, as the centrifuge rolls wear out, losses reach 40-45% (Goryainov KE et al. Technology of heat-insulating materials and products. M: Stroyizdat. 1982, p. 158). Mineral wool production waste is a fibrous-lumpy mixture consisting of slag layers of various sizes and geometries, vitrified sand ("kings") and cotton wool, which is usually treated with a toxic, polymerized binder. Mineral wool waste has a low bulk density (150-300 kg in m ³ ), is prone to caking, compaction and hovering in storage bins.

Due to the technological features of the melting of the charge in cupola furnaces, the use of fiber lump waste for remelting is impossible. Existing bath furnaces used in mineral wool production, due to the shortcomings noted above, are also unsuitable for the disposal of fiber-lumpy waste. In this situation, to solve the problem of disposal of fiber-lumpy waste, the most promising, according to the authors, are trenchless melting furnaces, in particular, according to the proposed method with column loading. It is necessary to fulfill one requirement: to increase the density and flowability of waste. To do this, the waste before loading into the furnace is subjected to hugging and / or crushing on wheeled runners.

Claims (12)

1. A method of gangless melting of rocks and mineral wool production waste in a gas furnace on a pitched hearth, comprising a thin-layer charge loading onto heat spots with a temperature of 1700 ± 250 ° C, formed by shock-jet heating at a gas plume impact rate with a hearth of 30-250 m / with continuous gravitational selection of the melt for production, characterized in that a constant volume of charge is formed on the pitched hearth of the furnace, consisting of a melted part - a charge pile in the form of a truncated cone, the larger base of which is located the wife on a sloping hearth, and the feeding part in the form of a charge column, the lower part of which is associated with a smaller base of the truncated cone, while the charge is melted provided that fire spots are placed along the perimeter of the larger base of the truncated cone with self-regulating replenishment of the melted part of the cone due to settling of the charge column under its own weight. 2. The method according to claim 1, characterized in that the mixture is melted by placing at least 1/3 of the area of the flame spots inside the perimeter of the larger base of the truncated cone. 3. The method according to claim 1, characterized in that the loading on the heat spots is carried out continuously by shedding the mixture from the slopes of the lost part of the cone. 4. The method according to claim 1, characterized in that the amount of charge in the charge column provides at least one hour of uninterrupted delivery of the melt in the absence of loading. 5. The method according to claim 1, characterized in that a constant volume of the charge with a feed charge column is formed close to the wall of the gas furnace. 6. The method according to claim 1, characterized in that the mineral wool waste is loaded and / or crushed before being loaded into the furnace. 7. A device for melting without rocks and mineral wool production, including a gas furnace with a ceramic pitched bottom, a water-cooled lined arch made of sheet steel and equipped with technological lances for installing gas burners, temperature sensors and charge loading, a drain tray for dispensing melt, characterized in that, at least over one of the tuyeres for loading the charge, a vertical water-cooled shaft is installed using a connecting flange, moreover, in the coak shaft ialno walls movably mounted barrel boot made of a refractory material. 8. The device according to claim 7, characterized in that at least a portion of the loading barrel is made of siliconized graphite. 9. The device according to claim 7, characterized in that the loading barrel is equipped with a vibration exciter for the descent of the charge. 10. The device according to claim 7, characterized in that on the pitched hearth under the boot barrel, an additional charge distributor is installed in the form of a massive cone-shaped body made of highly refractory material. 11. The device according to claim 7, characterized in that above the tuyeres for temperature sensors at least one remote non-contact temperature meter, oriented to heat spots, is installed. 12. The device according to p. 12, characterized in that an infrared thermometer is installed as a non-contact temperature meter.

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