MAPPING SPECULAR HEMATITE ORE BENEFICIATION ROUTES TO INDUSTRIAL APPLICATION STANDARDS

Abstract

The purpose of this study is to determine the appropriate method for micaceous iron ore processing and production per-industrial application standards. After identifying the characteristics of the samples (with XRF, XRD, mineralogical analyzes), gravity and magnetic separation tests were carried out. Quartz and hematite are the main minerals of micaceous hematite ores. Silica grade as the major impurity varies from 10% to 68%. The total iron content of the samples also varies from 15% to 62%. A jig and shaking table did not provide a good result in micaceous hematite beneficiation to achieve the standard of its specific applications. Gravity concentration by the spiral in the size range of -200 and -300 μm has led to the production of iron concentrates with a grade of 62.34% and 64.84%, respectively. The recovery values for the two experiments are 13.50% and 12.60%, respectively. Therefore, the spiral did not provide a good result in the micaceous iron ore beneficiation. High-intensity magnetic separation (1.2 T) has resulted in a product with a grade and recovery of 65.98% and 88.35%, respectively. The experimental design utilizing the Taguchi method considering the increasing of grade or recovery priority indicated that for micaceous iron beneficiation with a priority of recovery increasing, the feeder frequency, roll speed, and adjustable gate angle should be at 6.5 Hz, 95 rpm, and 20°, respectively. However, for micaceous iron beneficiation with a priority of grade increasing, the feeder frequency, roll speed, and adjustable gate angle should be at 2.5 Hz, 135 rpm, and 60°, respectively.

Alternate abstract:

Svrha je ovoga istraživanja odrediti prikladnu metodu za oplemenjivanje liskunaste željezne rude te izrada standarda primjenjivih u industriji. Nakon utvrđivanja karakteristika uzoraka (s XRF, XRD, mineraloškim analizama) provedena su ispitivanja gravitacijskom i magnetskom separacijom. Kvarc i hematit glavni su minerali liskunastih hematitnih ruda. Udio silicija kao glavne nečistoće varira od 10 % do 68 %. Ukupni sadržaj željeza u uzorcima također varira od 15 % do 62 %. Plakalica i koncentracijski stol nisu dali dobre rezultate u obogaćivanju liskunastoga hematita za postizanje standar-da njegove specifične primjene. No, gravitacijska koncentracija spiralom veličine zrna -200 i -300 μm rezultirala je kvali-tetom koncentrata željeza od 62,34 odnosno 64,84 %. Vrijednosti iskorištenja bile su 13,50 odnosno 12,60 %. Stoga ni spirala nije dala dobar rezultat u obogaćivanju liskunaste željezne rude. Visokointenzivna magnetska separacija (1,2 T) rezultirala je kvalitetom koncentrata od 65,98 % i iskorištenjem od 88,35 %. Eksperimentalni dizajn prema Taguchiju s obzirom na povećanje kvalitete ili iskorištenja pokazao je da za povećanje iskorištenja frekvencija dodavača, brzina bub-nja i kut separacijskoga noža trebaju biti na 6,5 Hz, 95 o/min i 20°. Međutim, za obogaćivanje liskunaste željezne rude s prioritetom povećanja kvalitete koncentrata frekvencija dodavača, brzina bubnja i kut separacijskoga noža trebaju biti 2,5 Hz, 135 o/min, odnosno 60°.