The objective of this study was to characterize the particle size distributions (PSDs) of chromite ores comminuted by different devices, i.e., subjected to different breakage modes and to compare the performances of the PSD functions selected. Different PSDs were obtained for five different mineralogical samples of chromite ores by jaw, cone and hammer crushing and ball mill grinding. The PSDs of the products were characterized to find the most suitable model by Gates–Gaudin–Schuhmann (GGS) and Rosin–Rammler (RR) functions. It was found that the PSDs of all chromite types in single‐pass devices, i.e., jaw and cone crushing were better described by the GGS model than RR model. The RR model gave the best results for all ore sample PSDs generated by retention type systems, i.e., hammer crushing and ball mill grinding. Both distribution functions gave higher R2 values as the size distribution became uniform. The results of piecewise regression were found very useful to improve the performance of GGS distribution in terms of correlation coefficients for samples from a hammer crusher and ball mill.

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In this study, the application of conventional flotation and floc-flotation methods to the wastewater containing suspended particles have been investigated. The experiments were carried out in two stages in the Jameson flotation Cell. The results obtained from the two methods were compared. The effect of flotation time and polymer type on the fine particle removal efficiency and residual turbidity was also determined. As a result of experimental studies, it was found that higher particle removal recovery and lower residual turbidity were obtained by floc-flotation compared to conventional flotation. Increasing flotation time increased fine particle floatability and decreased residual turbidity. In 1st stage of the experiments, 96.6% of the floatability recoveries and 304 NTU residual turbidity value was obtained with the combination of anionic polymer (SPP 508) and anionic surfactant (Aero 845) at the end of the 10 minutes flotation time. After 10 minutes of 2nd stage experiments, over 98% of floatability recoveries were obtained by floc flotation. The residual turbidity value of wastewater was decreased from the initial turbidity value of 12000 NTU to 78 NTU by anionic polymer, to 39 NTU by cationic polymer, and 27 NTU by a nonionic polymer.

Bu çalışmada; flokülant tipi ve miktarı, katı oranı oranı ve tane boyutu parametrelerinin flokülasyona işlemine etkisi kuvars numunesi kullanılarak belirlenmiştir. Önce, sabit katı oranı ve tane boyutunda hazırlanan atık su numuneleriyle anyonik, katyonik, noniyonik (iyonlaşmayan) flokülantlar kullanılarak flokülant tipinin ve miktarının etkisi araştırılmıştır. En iyi sonucu anyonik flokülantın verdiği tespit edildikten sonra, katı oranı ve tane boyutunun etkisi belirlenmiştir. Sabit tane boyutunda, artan katı oranı için daha fazla flokülant gerekmektedir. Sabit katı oranında, tane boyutu azaldıkça süspansiyonların kalan bulanıklığı da artmaktadır. Anyonik flokülant (SPP 508) kullanılarak sabit katı oranında (%0.06)-20 µm boyutu için 0.06 mg/L dozaj ile temizlenmiş suyun en düşük bulanıklık değeri 210 NTU'dan 9.6 NTU'ya kadar düşerken,-5 µm boyutu için 0.12 mg/L dozaj ile 430 NTU'dan 19.3 NTU'ya indirilebilmektedir.