APPLICATION OF THE HEAP BIOOXIDATION TECHNOLOGY FOR REFRACTORY GOLD CONCENTRATES

Öz

Rapid depletion of free-milling and oxide gold ores worldwide has forced the mining industry to turn to refractory gold deposits. Hence, research companies have examined novel methods for gold recovery, and advances have been made toward the extraction of gold from many different types of refractory ores. GEOCOAT® technology (heap biooxidation), a proprietary process developed by GeoBiotics, Inc., incorporates elements of two successful and commercially proven processes: heap leaching and biooxidation. The process involves coating of ground gold bearing sulfide minerals concentrate onto relatively coarse inert rock and then bio-heap oxidation of this coated material. In this study, initially the use of biotechnologies in the mining industry was introduced. Detailed information about heap biooxidation process was presented; experiments carried out at laboratory scale and at pilot plant scale by using this technology were summarized; and then commercial plant for heap biooxidation of refractory gold bearing pyrite concentrate was introduced.

Anahtar Kelimeler

• Heap Biooxidation,biomining processes,biohydrometallurgy

YIĞIN BİYOOKSİDASYON TEKNOLOJİSİNİN REFRAKTER ALTIN KONSANTRELERİNE UYGULANMASI

Öz

Dünya çapında öğütmeyle serbestleşebilen ve oksitli altın cevherlerinin hızla tükenmesi, madencilik endüstrisini refrakter altın yataklarına yöneltmiştir. Bunun sonucu olarak araştırma şirketleri altın üretimi için yeni yöntemleri incelemeye başlamışlar ve altının refrakter cevherlerin çok farklı türlerinden kazanımı yönünde atılımlar yapmışlardır. GeoBiotics Şirketince geliştirilen tescilli bir proses olan GEOCOAT® teknolojisi (yığın biyooksidasyonu); işletme ölçekte kendini kanıtlamış ve başarılı iki proses olan yığın liçi ve biyooksidasyon yöntemlerini birleştirmektedir. Yöntem; altın içeren öğütülmüş sülfürlü mineral konsantrelerinin göreceli olarak daha iri inert cevher tanelerinin üzerine kaplanmasını ve daha sonra bu kaplanmış malzemenin biyo-yığın oksidasyonunu içermektedir. Bu çalışmada ilk olarak madencilik endüstrisinde biyoteknolojinin kullanımı tanıtılmıştır. Yığın biyooksidasyonu prosesi hakkında detaylı bilgiler verilmiş, bu teknolojinin kullanımıyla laboratuar ve pilot tesis çapta yürütülen deneyler özetlenmiş ve daha sonra refrakter altın içeren pirit konsantresinin yığın biyooksidasyonunun gerçekleştirildiği ticari tesis tanıtılmıştır.

 

Anahtar Kelimeler

• Yığın biyooksidasyonu,biyomadencilik prosesleri,biyohidrometallurji

Kaynakça

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