RU2263640C2 - Raw for preparing mineral fiber - Google Patents

Abstract

FIELD: mineral materials.

SUBSTANCE: invention relates to raw used in preparing mineral fiber with the enhanced content of Al₂O₃. The raw charge for preparing mineral fiber comprises the following components, wt.-%: leukogabbro, 10-45; troctolite, 3-20; dolomite, 5-30; one or some rocks taken among the group: gabbro, diabase, basalt, peridotite, 7-58. Mineral fiber is prepared by melting the raw in indicated charge and by forming fibers from prepared melt. Invention provides improving curing indices of melt and reducing energy consumption of the process.

EFFECT: improved preparing method.

8 cl, 5 tbl

Description

The present invention relates to raw materials for producing mineral fibers, especially mineral fibers having a high content of Al ₂ O ₃ . The invention also relates to a method for producing such fibers using the raw materials according to the invention.

Aluminum is a desirable component in mineral wool fiber because it improves the temperature resistance of the mineral fiber and mineral wool made from it. When aluminum is included in an amount of about 15 to 25% by weight, calculated from Al ₂ O ₃ , the fiber also exhibits improved solubility in biological fluids. In the manufacture of mineral fiber during the production of mineral wool, bauxite has traditionally been used as the main source of aluminum. However, from the point of view of melting behavior and melt characteristics, bauxite is not an optimal raw material for introducing aluminum into the melt. In a smelting furnace, bauxite as such does not melt, but burns, and aluminum dissolves in the silicate melt, first forming oxides. This is a slow and energy consuming process.

Leucogabbro is a light rock containing aluminum, which can be found in many countries and on all continents; large deposits can be found, for example, in Canada, Greenland, Norway and Finland. These types of rock typically contain from 25 to 35% by weight of Al ₂ O ₃ .

The main mineral of leukogabbro is plagioclase. Plagioclase is an aluminum-containing solid silicate solution, the mineral composition of which extends from albite (NaAlSi ₃ O ₈ ) to anorthite (CaAl ₂ Si ₂ O ₈ ), and the mineral composition contains Al ₂ O ₃ in an amount ranging from 20 to 36 mass%.

Mineral wool feed feeds also typically contain ferrous and trivalent iron oxides, as well as magnesium oxide. Iron and magnesium have a beneficial effect on the temperature stability of the fiber. Typical amounts of iron to be included in the fiber are up to about 10% by weight, but iron can be replaced to some extent with magnesium.

Troctolite is a rock rich in iron and magnesium. Troctolite typically contains more than 35 volume% of the olivine mineral rich in iron and magnesium, with the remaining mineral being mainly plagioclase with smaller amounts of other minerals. Olivine is a solid silicate solution containing iron and / or magnesium, the composition of the mineral extending from magnesium-rich forsterite to iron-rich fayalite. Depending on the type of troctolite, troctolite may contain iron in an amount exceeding about 10 wt.% And even more, about 40 wt.%. In turn, the magnesium content can vary from about 5 wt.% To 20 wt.%. Thus, troctolite is a potential source of iron and magnesium for inclusion in the loading of minerals for the manufacture of mineral fibers.

The mineral wool feed feed also typically contains flux components to control and control the viscosity of the mineral melt. Such fluxes are usually compounds containing calcium and magnesium. In addition, dolomite rock is used as a flux component and as a source of calcium and magnesium. However, dolomite has the disadvantage that when used in large quantities in the feed, it tends to form foam, which is an undesirable characteristic in the melt under the conditions of fiber production. In addition, dolomite leads to the release of carbon dioxide from the melt, which is undesirable from the point of view of environmental protection. Moreover, such a release also inevitably means energy loss during production.

US Pat. No. 6,156,683 describes manually prepared fibers with a specific composition that can have low liquidus temperatures while maintaining adequate viscosity. US 5,932,500 relates to MMV fibers that have a specific solubility rate at certain pH values.

An object of the present invention is to provide a feed composition for the production of mineral fiber, which is not only optimal in terms of the chemical composition of the melt and therefore the fabricated fiber, especially with regard to the aluminum and iron / magnesium content, but which also gives a melt with good melting properties and melt characteristics. Another objective of the invention is to propose a feedstock feed, where some of the dolomite included for flux formation is replaced with minerals containing calcium and magnesium, making it possible to produce a melt with less energy input and less environmental stress. In an alternative embodiment, the invention makes it possible to obtain a melt with an increased content of calcium and magnesium without simultaneously increasing the load on the environment in the form of increased emission of carbon dioxide.

These goals are achieved according to the invention by loading the raw materials according to the invention, which contains leucogabbro, troctolite and dolomite in the following amounts

- leukogabbro from 10 to 45 wt.%

- troctolite from 3 to 20 wt.% and

- dolomite from 5 to 30 wt.%.

More specifically, the loading of raw materials according to the invention contains

- leukogabbro from 25 to 45 wt.%

- troctolite from 5 to 20 wt.% and

- dolomite from 5 to 30 wt.%.

In addition, the loading of raw materials may contain a certain amount of one or more rocks of materials selected from the group of basic and ultrabasic rocks consisting of gabbro, diabase, basalt and peridotite. Such an amount typically ranges from 7 to 58% by weight.

As used herein, the term “leucogabbro” refers to a rock that contains more than 65% by volume of the plagioclase mineral. Preferably, the anorthite content in the plagioclase mineral should be at least 50 mol%.

The term "troctolite" as used herein is intended to include any troctolite rock that contains more than 50 volume% olivine material. Preferably, the content of fayalite in the olivine mineral should be at least 35 mol%. Preferably, the range should be from 35 to 65 mol%.

In addition to the main components mentioned above, it is also possible to include reusable mineral materials, such as excess fibers and non-fiber-forming material, so-called pearls or waste from various industrial processes, such as flotation processes, slag, glass and / or cementitious products, etc. .d.

Using leucogabbro as a source of aluminum, better melt behavior of the feed is obtained, for example, higher viscosity and lower surface tension compared to using bauxite as a source of aluminum. This is due to the fact that in leucogabbro, aluminum is bound in the form of a salt with silicate, i.e. in the form of aluminum silicate. Therefore, there is no need to subject the raw materials to calcination or the formation of silicate, as in the case of bauxite, when it is necessary to calcine aluminum hydroxide. Thus, an aluminum-containing mineral melts more easily and with less energy than traditional materials.

Similar advantages in melt properties are also achieved by using troctolite as a source of iron and magnesium instead of traditional materials. Particularly valuable advantages are obtained when compared to using conventional iron-containing sources, such as iron ores, where iron is mainly bound in the form of hydroxides and sulfides as the sole source. Such inclusions without exception mean losses in the form of reduced metallic iron, which is collected in the lower part of the furnace, and / or energy losses in the form of water vapor generation, and / or environmental stress in the form of sulfur emissions.

Thus, using rocks consisting of leucogabbro and troctolite, in combination with the loading of raw materials, it is possible to introduce into the melt, and thus into the fiber, aluminum and iron / magnesium in the desired amounts for this purpose. In addition, the properties of the melt of the mineral charge can be influenced, and the minerals containing the silicate-bonded metal are provided for a smooth melting process to obtain a melt with a viscosity range suitable for spinning the fiber. In addition, energy losses can be avoided.

Using a feed of raw materials according to the invention, it is possible to produce a mineral fiber typically having the following composition, wt.%:

SiO ₂ 38-48 Al ₂ O ₃ 12-20 CaO 10-20 MgO 5-20 FeO 4-12 Na ₂ O + K ₂ O 0-4 TiO ₂ 0-4 Other components 0-4

More specifically, such fibers can have the following composition, wt.%:

SiO ₂ 42-46 Al ₂ O ₃ 14-17 CaO 10-20 MgO 5-20 FeO 4-12 Na ₂ O + K ₂ O 0-4 TiO ₂ 0-4 Other components 0-4

The feed can be placed in an electric furnace where it is melted using electrodes that are introduced into the feed. Alternatively, the feed can be placed in a cupola where coke is typically used as fuel. Typically, the feed is loaded into the furnace in granular form, and the particle size is typically in the range from a few millimeters to, for example, fifteen centimeters. In one embodiment, at least some of the feed is in bulk form, but it is also contemplated that some of the feed may be in the form of pieces. In particular, predominantly fayalite-rich troctolite in the form of pieces can be used without any serious melting problems in the smelter.

According to one embodiment of the invention, the raw material is brought into loose form and pressed into briquettes of a suitable shape and size using traditional methods and equipment for briquetting, for example, a method of pressing under vibration. Preferably, the briquettes contain a binder for raw materials, such as cement, clay, water glass, or organic binders, such as molasses. A method of manufacturing briquettes, essentially known to the person skilled in the art.

The present invention also relates to a method for producing mineral fiber, comprising obtaining a melt from a feed of raw materials, including leucogabbro, troctolite and dolomite in the following amounts

- leukogabbro from 10 to 45 wt.%

- troctolite from 3 to 20 wt.% and

- dolomite from 5 to 30 wt.%

and forming fibers from the melt thus obtained.

The method for producing fiber can be any method of spinning a fiber from a mineral melt known in the art. One suitable method utilizes a cascade type spinner. In this method, a stream of molten mineral material is produced for sequential feeding of a series of successive spinning rotors. During this process, the molten mass is effectively pulled into a fiber of suitable length and thickness.

Preferably, the feed loading includes

- leukogabbro from 25 to 45 wt.%

- troctolite from 5 to 20 wt.% and

- dolomite from 5 to 30 wt.%.

In addition, the loading of raw materials may include from 7 to 58 wt.% One or more basic and ultrabasic rocks selected from the group consisting of gabbro, diabase, basalt and peridotite.

The invention will be further described with reference to the following examples, which will in no way limit the invention.

EXAMPLE 1

Raw materials are made from finely ground and mixed rocks indicated in the following tables 1, 2 and 3, in the quantities shown, expressed as% by mass.

Table 1 Loading Mass% Mass% Mass% Mass% Mass% Leykogabbro 40 31 32,5 35.5 34.5 Peridotitis 30.5 17.5 32 33.5 Troctolite 13.5 thirteen 14.5 13.5 thirteen Gabbro 16 25 Dolomite 16 22.5 28 19 19 Amount 100.0 100.0 100.0 100.0 100.0

table 2 Loading Mass% Mass% Mass% Leykogabbro 28 28.5 28.5 Troctolite 9.5 14.7 13.5 Diabase 37.5 15,5 32,5 Dolomite 25 13.5 25.5 Centrifuge waste 17 Cement 6.4 Olivine 4.4 Amount 100.0 100.0 100.0

Table 3 Loading Mass% Mass% Mass% IV Mass% V Mass% VI Leykogabbro 25 25 10 fifteen 25 Basalt 28.5 28.5 Troctolite 12 thirteen 4 6 10 Metagabbro 45 45 31 Gabbro 16 15,5 Dolomite 18.5 eighteen 16 17 19 Peridotitis 25 17 fifteen Amount 100.0 100.0 100.0 100.0 100.0

Additional tests are carried out, where they make three downloads according to the invention (downloads I, II and III), as well as download (comparisons), where bauxite is used instead of leucogabbro as an aluminum source. The viscosities of the melts are measured, and the value for the load I is the average of two measurements, and the values for the load II and III are the average of eight and six measurements, respectively. Values for bauxite loading are based on an average of 18 measurements. The results are presented in the following table 4.

The viscometer in this case only measures relative viscosities to compare the viscosities of different melts. The measurements are carried out in a simple device, which includes a conical shape reservoir for producing a melt, the reservoir being in communication with a vertical barrel attached to its bottom. First, the melt flows a short distance through the vertical shaft and then flows into a horizontal pipe connected to and communicating with the vertical shaft. Depending on the viscosity of the melt, the melt flows at such a distance in the horizontal well until it hardens upon cooling. The lower the melt viscosity, the farther the solution flows into the pipe before cooling. The horizontal pipe has a measuring rod at its other end that can be inserted into the pipe opening. Then measure the distance traveled by the melt before hardening, as the depth of introduction of the measuring rod into the pipe until it runs into the hardened melt. Thus, a higher value of the insertion depth in mm means a higher melt viscosity and vice versa.

Table 4 Download (wt.%) I II III Comparisons Peridotitis eighteen 17 17 21 Metagabbro nine 14.5 16 46 Dolomite 19 twenty 21 15,5 Leykogabbro 38 34 34 Troctolite 16 14.5 12 Blast furnace slag 10 Bauxite 7.5 Viscosity 100 mm 108 mm 98 mm 80 mm

From the results it can be noted that when leucogabbro is used as the source of aluminum, instead of bauxite, a relatively significant increase in viscosity is obtained, while the loadings I, II and III are relatively the same.

The following table 5 shows the composition of the downloads I, II and III, as well as the composition of the load comparison. In addition, fiber compositions made from batches IV, V and VI of Table 3 are included.

Table 5 Composition (wt.%) I II III Comparisons IV V VI SiO ₂ 42.1 42,2 42,2 42,4 46.2 45.5 43.7 Al ₂ O ₃ 17,2 16.7 16.9 16.6 14.2 15.1 16,0 CaO 17.1 17.3 17.9 17.5 15.6 16,2 17.1 MgO 13.3 13,4 13,2 12.5 12.9 12,4 12.7 FeO 6.9 6.9 6.5 6.8 7.0 6.9 6.8 Na ₂ O + K ₂ O 2.1 2.1 2.1 2.6 2,8 2.6 2,4 TiO ₂ 1,1 1,1 1,0 1,2 1,1 1,1 1,1 Other components 0.2 0.3 0.2 0.4 0.2 0.2 0.2

Claims (8)

1. Loading of raw materials for the production of mineral fiber, including leukogabbro, troctolite and dolomite in the following amounts, wt.%: Leykogabbro 10 - 45 Troctolite 3 - 20 Dolomite 5 - 30 and also from 7 to 58 wt.% of one or more rocks selected from the group consisting of gabbro, diabase, basalt and peridotite. 2. The loading of raw materials according to claim 1, including, wt.%: Leykogabbro 25 - 45 Troctolite 5 - 20 Dolomite 5 - 30 3. The loading of raw materials according to any one of the preceding paragraphs, in which the plagioclase mineral in leukogabbro contains at least about 50 mol% of anorthite. 4. Loading of raw materials according to any one of the preceding paragraphs, in which the olivine mineral in troctolite contains at least about 35 mol.% Fayalita. 5. The loading of raw materials according to any one of the preceding paragraphs, at least in part, in the form of briquettes, compressed from bulk raw materials. 6. A method of producing mineral fiber, comprising obtaining a melt from a feedstock containing leucogabbro, troctolite and dolomite in the following amounts, wt.%: Leykogabbro 10 - 45 Troctolite 3 - 20 Dolomite 5 - 30 as well as from 7 to 58 wt.% one or more rocks selected from the group consisting of gabbro, diabase, basalt and peridotite, and the formation of fibers from the obtained melt. 7. The method according to claim 6, in which the download includes, wt.%: Leykogabbro 25 - 45 Troctolite 5 - 20 Dolomite 5 - 30 8. The method according to any one of paragraphs.6 and 7, in which the load, at least in part, is in the form of briquettes, pressed from bulk raw materials.