GREEK BAUXITE DESCRIPTION
The Greek bauxite deposits appear in Central Greece (Parnassos-Ghiona Zone) and are of karstic-Mediterranean type. There are three horizons of which only two, the middle and, especially, the upper horizons, are exploited having the following typical composition:
|Chemical composition||Middle horizon
|Al2O3 %||52 - 56||56 - 60|
|Fe2O3 %||20 - 22||20 - 25|
|SiO2 %||8 - 12||2 - 3|
|TiO2 %||2.2 - 2.8||2.0 - 3.0|
|L.O.I. %||12 -14||12 - 13|
|Organics %||< 0.03||< 0.03|
The mineralogical composition is the following:
|Boehmite 10 - 30%
Diaspore 20 - 50%
Hematite 20 - 25%
|Anatasse 2 -3%
Calcite 1 - 5%
Kaolinite 0 - 5%
Quartz 1 - 2%
The proven deposits are in the order of 70 million tonnes and the proven and probable reserves around 150 million.
Parnasse bauxite is mined in the mountain region of Parnassos and Ghiona (about 200 km north-west of Athens) at an average altitude of 800m.
The ore is extracted by surface and underground mining (by the method of room and pillar), and production reached 800.000 tonnes in 1999.
The underground mining is considerably performed by S&B. The newest machinery and techniques are used so as the product has the best properties.
BENEFICIATION AND LOADING
Bauxite is transported to Itea, a town in Fokis Prefecture, (about 30 km to the south of the mines) where the crushing, screening and loading installations are located. In addition, in Itea are located a beneficiation plant and the quality control laboratory.
"Run-of-Mine" bauxite is sorted according to its chemical composition, crushed and screened into the following fractions: 100-200mm, 50-100mm, 30-50mm and 0-30mm.
For finer classification, when required, wet sieving technics are employed.
The different granulometric fractions of different qualities are then placed in designated stockpiles ready to be blended to form material of required specifications.
The CaO content of the bauxite can be reduced to less than 0.3% by means of the beneficiation plant that employs the dynamic heavy media method for separation.
The bauxite is loaded from the private loading facilities, which have the following specifications
ZDROJ: http://www.sovereign-publications.com, kráceno