Large-Diameter Dense Medium Cyclone Performance in Low-Density/High Near-Gravity Environment

Abstract

This article details the key outcomes for Australian Coal Association Research Program (ACARP) Project No. C20045, a Stage 2 project following on from Stage 1 ACARP project No. 17036. The primary purpose was to measure very large dense medium cyclone (DMC), that is, 1450 mm diameter, performance under a series of challenging conditions to generate data that start to deviate from acceptable performance. A range of feed solids loading/M:C ratios (3:1 to 6:1), feed pressure conditions (5D to 9D), low-density, high near-gravity (up to 42% +/−0.1 RD) separations were tested with the objective of identifying the point at which this DMC would begin to exhibit performance deterioration. The performance assessment also encompassed the nonmagnetics in the medium samples to assess the efficiency limits at very fine size fractions. The outcome of this assessment showed similar performance achieved that of both smaller diameter cyclones and from higher density, lower near-gravity separations determined on this same cyclone in the Stage 1 project. The performance of the cyclone only began to show deterioration at size fractions below a GMS of 1.0 mm and it is only in these size fractions where the reported “breakaway” particle size would appear to have relevance.

Keywords:

• Cyclone diameter
• Ep by size
• High near-gravity
• Large DMC
• Low-density
• Medium-to-coal ratio

Acknowledgements

The success of this project is a direct result of the efforts of the specialist sampling staff who completed the site sampling and sample preparations, as well as the excellent support from the testing laboratory. This combination has delivered a quality, public domain dataset to benefit all industry personnel. The test site personnel provided us support throughout the testing period, as well as making all of the critical production arrangements to deliver a consistent feed for the project.

Notes

Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/gcop.