Doctor of technical sciences Bektybaev A.D., candidate of technical sciences, associate
professor, Oryngojin E.S.,
Mining engineer Kapanov S.T., mining engineer Azizov
F.E.
The Republic of Kazakhstan
Mining Institute after D.A. Kunaev, Almaty
MTD «Vostoknedra»,
Ust-Kamenogorsk
«Semei-Komir» Ltd.,
Semipalatinsk
THE STUDY OF COAL QUALITY IN THE
COURSE OF DEVELOPMENT OF THE FIELDS KARAJYRA IN THE EASTERN KAZAKHSTAN
In the Eastern Kazakhstan there is coalfield Karajyra situated 130 km to the south-west from the city of
Semipalatinsk in Jana-Semei region. The area of the field covers 21,4 km2.
The rocks composing the mantles
and coal-bearing sediment are mainly represented with mudstones, siltstones,
sandstones, conglomerates, coals, coaly rocks, clays, sands, loams and clay
sands.
Under the soil and vegetation
layer not more than 0,35 m thick, there are almost everywhere loams and in the
south-eastern part - sands. The thickness of loams varies from 1,0 to 6,0 m.
Prevalent thickness of sands is 1,0-4,0 m. In the eastern part of the field
almost everywhere there are Neogene clays. Their thickness varies from 1,0 to
39,0 m.
The quality of the coals and
their tectonic properties of the field Karajyra are mainly characterized with
the core of the wells of core boring. The studies of all core samples have been
done by the laboratories JSC «Centrgeolanalit» (Karaganda). For special studies
of coals the specialized institutes have been attracted: the Institute for
combustible minerals (IGI, Moscow), the Institute for enrichment of solid
combustible minerals (IOTT, Lyubercy), the Ural branch of heat engineering
scientific and research institute (UralVTI, Chelyabinsk), the Eastern
coal-chemical scientific and research institute (VUHIN, Ekaterinburg), the
Eastern scientific and research institute for safety of operations in mining
industry (VostNII, Kemerovo), Scientific and research and research and
development institute for issues of development of Kansko-Achinskiy coal basin
(KATEKNIIugol, Krasnoyarsk), the Kazakh state scientific and research and
research and development coal institute (KazNIIugol, Karaganda), the Institute
for organic synthesis and coal fuel chemistry of AS RK (IOSU, Karaganda), the
Kazakh scientific and research institute of energetics (KazNIIenergetika,
Almaty).
The main parameters of coal
quality are: ash content, humidity, lump size (grade), content of sulphur,
devolatilization, combustion heat, content of mineral admixtures. For the rest
of the parameters only average norms are set used for general characteristics
of quality [1].
On the site of primary
development, coal strata II and I are mainly composed of semiglittering coals
(59-63%), to smaller extent of semidull (21%) and mat (9-11%) ones. Glittering
and mat ash coals are present in small quantity (1-2%). Mineral inclusions in
coals are mainly syngenetic, are presented with pelitomorphic clay substance
available mainly in the form of lenses, with spherulites of siderite, calcite,
less often with grains of pyrite and quartz.
According to the option of
conditions approved by the project 1 m - 25% combustible rock is assumed to be
coal with the ash content of up to 40%, coaly mudstones – with ash content of
40,1-60,0%, weak coaly – with ash content of 60,1-70,0%.
Combustion heat (GOST 147-74) of
coals varies to small extent. The highest combustion heat of coals by layers
varies from 23,68 mJ/kg (5656 kkal/kg) for the layer II1+2 up to
25,11 mJ/kg (5998 kkal/kg) for the layer II3, in average amounting
up to 24,73 mJ/kg (5908 kkal/kg). According to the highest combustion heat of
humid ash-free fuel, in conformity with the GOST 25543-88 coals refer to the
stone one (more than 24 mJ/kg).
Coal washability (GOST 10100-84)
has been studied by means of core stratum industrial samples, each stratum
individually. In conformity with GOST, the extent of cal washability is
difficult and very difficult and depends on the ash content of ordinary coal.
Sinterability (GOST 9318-79,
GOST 1186-87). Coals of the field are non-coking. In all strata interceptions
the thickness of stratum, Roga index and the index of free swelling are equal
to zero.
Grade composition (GOST
25543-88). Coals of the field belong to the coals with long flame. The
indicator of reflection of vitrinite in all tested strata interceptions is more
than 0,40%, combustion heat of humid ash-free fuel is more than 24 mJ/kg.
According to the content of nonplastics components (1-5%) the coal is
vitrinite.
Moisture (GOST 8858-76,
11014-75, 8719-70). Maximum moisture capacity
varies from 11,1 to 25,1%, amounting in average for the field and the
site of primary development 16,7%.
Devolatilization (GOST 6382-80)
in ordinary coal varies from 44,6 to 49,4%, at the average value of 46,8%.
Sulfure (GOST 2059-75). The
coals are low sulfur. The content of sulfur in ordinary coal varies from 0,20
to 0,67% at the average value of 0,37%.
Phosphorus (GOST 1932-82).
Phosphorus content in coals is low, it varies from 0,01 to 0,106% at the
average value of 0,042%.
Literature:
1.
P.I. Tomakov, V.V. Mankevich. Open mining of coal and ore fields. Editorial
house MGGU. – Moscow, 2000.