Reducing the biased slurry feed subdivision in vertical pipe T-junctions using partition wall and stratifier

Abstract The biased subdivision of slurry feed to a number of unit operations in parallel has been recognised as a problem to be solved in coal and mineral processing industry. This biased subdivision results in each unit (e.g. cyclones, spirals and flotation units) in a multi-unit system to operate with different separation density, particle size distribution and solids concentration. Consequently, some of the units may operate under conditions far from favourable ones, leading to a significant decrease in the operating efficiencies of the sizing and cleaning units in coal preparation plants. The objective of this work is to develop new and more robust approaches or devices far unbiased slurry subdivision. New slurry flow splitters have been proposed by modifying simple T-type splitters with a partition wall or a stratifier. A series of experiments were carried out with a vertical pipe having a T-junction to compare the performance of various approaches to slurry splitting. Effects of flowrate, particle size, density, solids concentration and branch orientation were studied, and the results show that new splitters are very effective in reducing the degree of biased subdivision of slurry flows in vertical T-junctions. Pressure drops in the flow splitters were also measured and compared.