Rocks - raw material for manufacture of basalt fibers.

Basalt is magmatic (formed of deep silica-alumina melts) rock of the basic structure (the maintenance silica SiO2 makes 50 5 %), fallen asleep in the top layers of an earth's crust or on a surface.

By results of several thousand analyses of rocks of a 16-kilometer layer of the earth's crust accessible to geological studying, and under the average maintenance of chemical elements in an earth's crust prevalence of breeds in this layer which is expressed in a following proportion is established: igneous rocks - 95 %; metamorphic - 4 %; sedimentary - 1 %.

On analytical data igneous rocks consist of 2/3 parts of a granite and 1/3 parts of basalt. Thus, the maintenance of basalt in an earth's crust exceeds 30 %.

The basic minerals of which basalts consist, are: - plagioclase (silica-alumina, sodium and calcium); - pyroxene (chained silicates); - peridots - ore minerals (magnetite, ilmenite) and volcanic glass.

Basalts contain (on weight): 45-55 % SiO2; 10-20 % Al2O3 and up to 20 % FeO + Fe2O3 and MgO. Except for the cores oxide basalts contain practically all elements of the table of Mendeleyev, and, mainly, in the form of mineral connections. Completely crystal breeds of similar structure refer to dolerite, the basalts destroyed and changed by secondary processes are known as diabases and basalt porphyry. The deep analogue of basalt carries the name gabbro.

In SE STC "BAVOMA" are developed techniques of tests of rocks by definition of their suitability for manufacture of a various kind of basalt fibers. By experts have been investigated more than 500 deposits of rocks in various regions of the world. Analyzing obtained data, and spending additional tests, we can choose optimum sources of raw material in the set region for manufacture of all kinds of basalt fibers.

SE STC "BAVOMA" is the base organization in Ukraine in the field of standardization of raw material from rocks for manufacture of a various kind of basalt fibers.

Features of chemical and mineralogical structures of basalt define their ability to glass formation and fiberizating. Differences in chemical and mineralogical structure of basalts are reflected in their properties of melts, and, hence, and on a final kind of a fibrous material.

On the basis of the analysis of the data received as a result laboratory - technological researches more than 1000 tests of basalts of deposits of Ukraine, the CIS, Vietnam, Korea, Canada, Japan, etc. in the center are developed criteria of an estimation of suitability of rocks as unicomponent raw material for manufacture of a various kind of fibers with reference to existing technologies. The databank of rocks of various regions of the world, suitable for reception of basalt fibers is created.

Raw materials from rocks (according to 88.023.022-96) represents fragmented averages, the cores and metamorphizeing the ultrabasic rocks of a volcanic origin of type of basalt: basalt, gabbro, amphibolites, diabase, porphyry and others (further under the text raw material). Raw materials it is intended for its use in manufacture of canvases from basalt staple thin, superthin and thickened fibers according to .2.7-73.1-05434140-029-2002, the chemical compound of raw material corresponds to the requirements resulted in table 1.

Chemical compound of rocks suitable as unicomponent raw material for manufacture of a various kind of fibers

Table 1
The name of components Mass fraction, %
Coarse Continuous (Roving) Thin staple Superthin staple, Coarse
Dioxide of silicon (SiO2)48,0-53,047,5-55,043,0-51,046,0-52,0
Dioxide of titanium (TiO2)0,5-2,00,2-2,00,2-3,00,5-2,5
Oxide of aluminium (Al2O3)13,0-18,014,0-20,010,0-17,013,0-18,0
Oxide of iron (FeO+Fe2O3)8,0-15,07,0-13,510,0-18,08,0-15,0
Oxide of calcium (CaO) 6,5-11,07,0-11,08,0-13,06,05-11,0
Oxide of magnesium (MgO)3,0-10,03,0-8,54,0-15,03,5-10,0
Oxide of natrium and potassium(Na2+K2O) 2,0-7,52,5-7,52,0-5,02,0-7,5
Oxide of manganese (MnO), no more than0,50,250,40,5
Oxide of sulfur (SO3), no more than1,0 0,21,00,5
Losses of weight at burning (l.w.b.), no more than5,05,05,05,0
Free quartz, no more than3,02,03,03,0
module of viscosity v.1,9-2,52,3-2,71,7-2,01,8-2,4

The mineralogical structure of test of rocks is defined in transparent sections on a polarizing microscope at increase in 100+. The maintenance of the minerals composing rocks of type of basalt, fluctuate over a wide range. In tab. 2 boundary maintenances of minerals in rocks, suitable for manufacture of basalt fibers are resulted.

It is necessary to note, that calculation of suitability of rocks on chemical and mineralogical structure, has only preliminary character (for primary selection of laboratory tests), and in the further it is necessary to spend the laboratory researches-technological including research, both properties of rocks melts, and conditions of fiberizating and definition of physical and chemical characteristics of fibers.

Technical requirements to rocks for manufacture of basalt fibers.

Averages, the basic, and metamorphize the ultrabasic rocks of a volcanic origin (basalts, diabases, amphibolites, porphyry, etc.) should correspond to following requirements:

  1. Capacity of an equivalent doze of an ionizing radiation should not exceed the established norm (0,30 mkiloelectronvolt/hour)).
  2. The chemical compound should correspond to the requirements resulted in tabl.1.
  3. The weight of test for carrying out of laboratory-technological researches should make 8-10 kg. The size of fraction - 50-100 mm.
  4. In the presented test mechanical extraneous impurity in the form of metal, quartz, sandy-argillaceous and other breeds should not contain.
  5. Each test should be accompanied by the passport in which should be reflected a place of selection, a deposit, a way of selection (gross, handful, etc.), and also results of the chemical analysis lead by the Customer.

Mineralogical structure of rocks, suitable as Unicomponent raw material for manufacture of various kinds of fibers

Table 2
Minerals Boundary quantity of minerals, volume %
For thin staple fibers For superthin staple fibers For continuous fibers
plagioclase20-5520-5535-70
pyroxene0-455-401-35
ore0-120-120-12
peridot0-150-150-15
Natural glass0-252-450-50
quartz0-20-20-..
amphiboles0-300-150-10
biotite0-20-30-3
palagonite0-200-200-25
peach0-350-350-35
epidote-zeolite0-100-150-5
carbonate0-150-10 0-8

Physical and chemical properties of melts

Requirements are put in a basis of criteria of suitability for reception of fibers on mineralogical and chemical structures of rocks, conditions of fusibility and their properties of melts:

  • shear viscosity
  • temperature of the superior limit of crystallization,
  • wetting ability,
  • density of melt,
  • thermodynamic characteristics, etc.

Physical and chemical properties of rock melts, under condition of their sufficient uniformity and homogeneity, depend on concentration and a parity of the main things melt-generative oxides. The most important physical and chemical parameters of melts are viscosity and temperature of the superior limit of crystallization. Viscosity of rock melts depends on a chemical compound serving by initial basis for calculation of the acid-base of parameters, describing structural features of system.

On a chemical compound modules of acidity (MA) and modules of viscosity (MV) pay off. The module of acidity reflects the acid-base of the characteristic of rock, and the module of viscosity - viscosity characteristics of rock melts which are one of the main parameters of development of fibers.

Some properties of rock melts, suitable for manufacture of basalt fibers, are resulted in tabl.3.

Properties of rock melts

Table 3
Characteristics, °UnitValue
Melting temperature  °1100-1450
Temperature of the superior limit of crystallization °1200-1310
Limiting wetting angle of platinum-rhodium alloy by melt1350degree(5....8°)
1250degree(15....30°)
Density of melt1450kg/m32300-2600
1300kg/m32400-2700
Resistivity1450Ohm•m0,4-0,5
1300Ohm•m0,5-0,65
Modulus of elasticity1450-1300GPa16,9-25,4
Surface tension1450mN•m350-410
1300mN•m400-500
Shear viscosity1450dPa•s10-150
1300dPa•s70-1000
Volume viscosity1450-1300Pa•s30-1500
Adiabatic compressibility1450-1300Pa•s-11,5-6,0
Thermal/heat capacity J/kg•1300-1400
Thermodynamic properties:
Viscous flow thermal/heat capacity, no more than
Free activation enthalpy
Activation entropy
J/mole
J/mole
J/mole •K
310
180-220
30-40
phone/fax: (044)517-4818
phone: (044)517-0963