The separation of fine, high density particles from a low‐density soil matrix using a hydrocvclone

Abstract

Tests were carried out to examine the performance of a 25 mm diameter hydrocyclone for separating fine (‐150 μm) particles. Mixtures of fine quartz and magnetite or ferrosilicon of similar size ranges were used to represent low density (e.g., soil) and high density (e.g., heavy metal contaminant) particles, respectively, as might be encountered in a waste remediation or recycling process. Separations were made using various cyclone geometries (e.g., cone angles, discharge openings) and operating conditions (e.g., solids concentration, flow rate). The products were analyzed for heavy metal content and then sized at 25 μm to determine the recoveries for both the total and the +25 μm fractions. The results indicated that there was a trade off between the recovery of low and high density components.

Key words:

• Water‐only cyclone
• soil washing
• autogenous cyclone
• waste remediation
• process recycling.