Investigation of Hydrocyclone Function in the Process of Solid Particles Separation in Stone-Cutting Industry

At the present, treatment and recycling of stone cutting industry wastewater is performed by old settling basin method and filter press method which need so much water, therefor, in this method a new method is proposed and investigated based on hydraulic centrifugal force by using a hydrocyclone. The effect of operational parameters such as pressure, concentration and type of particle samples have been studied on a hydrocyclone efficiency with a diameter of 24 mm. The experiments were designed by using Design Expert 7 software based on response surface method (RSM). Analysis of experimental data was conducted based on composite central design method (CCD). Experiments were conducted in 22 series with different conditions. In this study, stone powder particles were collected from wastewater of stone cutting plants. Two stone powders samples were achieved from Granite and Travertine stones with densities of 2720 and 2550 kg/m3 with particle sizes of less than 200 μm. Particles sizes were measured by Particles Size Analysis method and particles shape were determined by using (SEM). The results demonstrated that the separation efficiency for both of samples is proportional with pressure so that the more the input pressure, the more the separation efficiency. On the other hand, increasing the concentration causes a decrease in separation efficiency. Based on the results, the more the input pressure, the more the flow rate, however concentration in the investigated range has no significant effect on flow rate. The best separation efficiency was achieved in the pressure 2.63 bar and concentration 1.6 weight percent for Travertine sample with a value of 90.31 percent and for Granite sample in the pressure 3 bar and concentration 3 weight percent with a value of 91.45 percent.