THE EFFECT OF GRINDING MEDIA PERFORMANCE ON WET MILLING OF CALCITE

This study aimed to conduct systematic research on the design of high-density zircon (ZrO2) grinding media (0.2-1 mm) in a laboratory-scale media mill (750 ml) for wet grinding of calcite (CaCO3, d50= 5.4 µm). Sub-micron grinding experiments were carried out by using different amounts of finer grinding media (25%, 50% and 75%) and different size ratio of finer-coarser media (0.2 and 0.5). Besides, the surface areas (Sbw, m2 /kg) of grinding media on grinding performance were investigated. If the best experimental results are compared (M1 and M4), it is found that the Sbw of the bimodal media (M4) is 75% larger compared to that of monosized media (M1). The experimental results were analyzed based on product size (d50, d80), cumulative undersize curves and specific surface area (SW, m2 /g). The findings showed that only the finer grinding media was not very effective at 600 rpm.

Kalsitin Yaş Öğütülmesinde Öğütücü Ortam Performansının Etkisi

Bu çalışmada, kalsitin (CaCO3, d50=5,4 µm) yaş öğütülmesi üzerine laboratuvar ölçekli bilyalı değirmende (750 ml) yüksek yoğunluğa sahip zirkon (ZrO2) bilya (0,2-1 mm) tasarımıyla sistematik bir çalışma amaçlanmıştır. Farklı miktarda ince bilya (%25, %50 ve %75) ve farklı ince-iri bilya oranları (0,2 ve 0,5) kullanılarak mikron-altı öğütme gerçekleştirilmiştir. Ayrıca, öğütücü ortamın yüzey alanlarının (Sbw, m2 /kg) öğütme performansına etkisi araştırılmıştır. En iyi deney sonuçları karşılaştırıldığında (M1 ve M4), karışık bilya boyut dağılımının (M4) yüzey alanı, tek tip bilya boyut dağılımının (M1) yüzey alanından %75 daha fazladır. Deneysel sonuçlar ürün boyutu (d50, d80), kümülatif elek altı eğrisi ve spesifik yüzey alanı (SW, m2 /g) dikkate alınarak değerlendirilmiştir. Sonuçlar, sadece ince boyutlu öğütücü ortamın 600 devir/dk hızda çok fazla etkili olmadığını gösteriyor.

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