Bingöl (Yedisu), Diyarbakır (Hani ve Ergani) ve Elazığ (Alacakaya) Kromlarının Zenginleştirilmesi

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.

Anahtar Kelimeler

• Bingöl (Yedisu) krom cevheri, Diyarbakır (Hani ve Ergani) krom cevheri, Elazığ (Alacakaya) krom cevheri, sallantılı masa ile zenginleştirme

Enrichment of Bingöl (Yedisu), Diyarbakır (Hani ve Ergani) ve Elazığ (Alacakaya) Chromite

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.

Anahtar Kelimeler

• Bingöl (Yedisu) chromite, Diyarbakır (Hani and Ergani) chromite, Elazığ (Alacakaya) chromite, concentration with shaking table.