Öz
Bu çalışmada Bingöl (Yedisu), Diyarbakır (Hani ve Ergani) ve Elazığ (Alacakaya) kromlarının
zenginleştirilmesi araştırılmıştır. Bu amaçla deneysel çalışmalar Bingöl-Yedisu, Diyarbakır-Hani- Ergani ve
Elazığ-Alacakaya bölgelerinden alınan krom örnekleri üzerinde yapılmıştır. Öncelikle krom örneklerinin
karakterizasyon çalışmaları ve elek analizleri yapılmıştır. Daha sonra farklı boyutlarda sınıflandırılan krom
örnekleri sallantılı masa ile zenginleştirilmiştir. Yapılan çalışmalar sonucunda %45,24-46,33 Cr2O3 içeren
konsantreler %87,70-89,10 verim değerleri ile elde edilmiştir.
Öz
Chromium is one of the modern industry’s essential
element and important raw material in the
production of special steel and ferrochrome alloys.
Around 90% of mined chromite ore is converted into
different grades of ferrochrome by the metallurgical
industry. Stainless steel industry consumes about
80% of ferrochrome produced (mainly highcarbon/charge
grade).
Chrome ores are divided in three classes according
to their grades and uses- (a) metallurgical grade, (b)
chemical grade and (c) refractory grade chromites.
Metallurgical chromite has Cr2O3 contents of 44-
56% with Cr/Fe ratios more than 2.5. Its widespread
use in metallurgical industry is attributed to its
capability of enhanced properties such as resistance
to corrosion, creep and impact strengths and
hardenability.
Chemical-grade chromite contains large amounts of
iron which after results in Cr/Fe ratio of close to 1.
Refractory grade chromites contain relatively large
quantities of Al2O3 (greater than 20%) and with a
Cr2O3 + Al2O3 level more than 60%. Chromium is
used in refractories to enhance thermal shock and
slag resistance, volume stability and structural
strength.
Chromite ores usually are of high enough grade to
be sold directly. Sometimes simple hand sorting and
washing are sufficient to upgrade the run-of-mine
ores. On the other hand, low grade and finely
disseminated ores have to be upgraded by the use of
concentration techniques which can be classified as
follows: (a) gravity concentration, (b) magnetic
separation, (c) electrostatic separation, and (d)
flotation and selective flocculation. In selection of
these methods, mineralogical, physically and
chemically properties of ores are firstly important.
In additional, reservoir, grade and production speed
of mining methods are effected to selection of
beneficiation methods.
Most of the chromites can be concentrated by
gravity concentration techniques owing to the
difference in specific gravity between the chromite
and the gangue minerals which are usually olivine
and serpentine. Shaking tables, jigs, spirals and
Reichert cones are widely used for this purpose.
In this study upgrading of Bingöl (Yedisu),
Diyarbakır (Hani ve Ergani) and Elazığ (Alacakaya)
chromite was investigated. For this purpose,
experimental studies were made on the chromite
samples taken from Bingöl-Yedisu, DiyarbakırHani-
Ergani and Elazığ-Alacakaya regions.
Firstly, the chromite samples were crushed to under
3 mm particle size. After the samples were classified
into different size fractions and microscopic
inspections of the size fractions were made.
Concentration experiments were carried out by
using a laboratory type standard Wilfley shaking
table (Wilfley Mining Machinery Co.,
Ltd.Wellingborough, UK. As a result, it was found
that the concentrates containing 45.24-46.33%
Cr2O3 content with 87.70-89.10% recovery was
achieved.
Ayrıntılar
| Diğer ID | JA98BA42PT |
|---|---|
| Bölüm | Makaleler |
| Yazarlar | |
| Yayımlanma Tarihi | 1 Aralık 2014 |
| Gönderilme Tarihi | 1 Aralık 2014 |
| Yayımlandığı Sayı | Yıl 2014 Cilt: 5 Sayı: 2 |