The biased subdivision of slurry feed to a number of unit operations (e.g., cyclones) in parallel results in each unit to operate under different separation density, volumetric flowrate, feed pressure, and feed concentration. Consequently, some of the units may operate under sub-optimal conditions, leading to reduced operating efficiencies of sizing and cleaning units. The objective of this work is to identify factors causing biased slurry subdivision in multi-port distributors and to improve the understanding of the complex two-phase flows involved. A number of experimental investigations were carried out on a pilot-plant scale experimental system. The bias with regard to solids concentrations and particle size distributions of substreams was found to decrease with increasing the feed flowrate to the distributor. This bias also results in significant variations in the feed distribution and the performance of the hydrocyclones. Increasing the solids concentration in the slurry feed decreases the bias. There is also a strong dependence of the degree of bias on the density of particles in the slurry. The biased slurry subdivision is mainly caused by non-unifrom solids segregation induced by low line velocity, which reduces the suspension forces on the particles and increases the residence time of particles in the distributor. It has been demonstrated from the experiments that the low line velocity is due to the large diameter of the distributor. Experimental results show that unbiased slurry subdivision can be achieved using a #x2018;slim#x2019; distributor.
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