This paper presents the separation performance and liquid flow characteristics of a miniaturized uniflow hydrocyclone in removing micron and sub-micron heavy metal particles from water. This new laboratory hydrocyclone is designed based on the idea of improving the separation efficiency besides the simplifying of geometry and fluid flow. Furthermore, the hydrocyclone device is downscaled to enhance the separation of the fine particles. Instead of traditional hydrocylones, there is only one swirling flow of liquid and both outlet ports are in the same direction. Small values of Eu number disclose low energy requirement in this arrangement. The effects of feed flow rate and solid content were studied. The results show good separation efficiency ranging from 0.69 to 0.9 for varying flow rate of 15 to 45 ml/s. There is a point at which the highest separation performance is obtained besides satisfying energy consumption, determined as high-performance point of separation. Also, experiments with varying solid content from 0.1 to 4g/l disclose that the solid content has a slight effect on separation performance, below 3 g/l but it may causes significant changes, above that solids concentration. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.