Application Of Hydrocyclones In Tailings Dry Stacking

In tailings dry stacking, hydrocyclones are used in combination with thickeners and high-frequency dewatering screens to reduce the moisture content of tailings to below 15%.

Tailings Dry Disposal Process

The tailings slurry is concentrated by a hydrocyclone, achieving an underflow concentration of 65%-70%. The underflow is then directly dewatered by a dewatering screen, with the overflow containing less than 16% moisture. This overflow is then transported by belt conveyor to a dry stockpile for dry stacking. The underflow is returned to the hydrocyclone feed, forming a simple closed-loop system with the dewatering screen, maximizing the output of dry material from the dewatering screen. Furthermore, the overflow from the hydrocyclone enters a deep cone thickener and filter press for further concentration and dewatering to achieve complete tailings dry disposal.

Application of hydrocyclones in tailings dry stacking

1. Tailings pre-concentration

Hydrocyclones are commonly used for tailings pre-concentration because they require little floor space and have a fast concentration rate. Hydrocyclone pre-concentration can increase the concentration of tailings from 10% to 40% to 45% to 70%, resulting in a high sediment yield. For tailings in metal mines, hydrocyclones can achieve a sediment concentration of over 60%, with a sediment yield of 40% to 70%. Using hydrocyclones for tailings concentration and dewatering operations can improve tailings technology and expand production.

2. Tailings enrichment and recovery

A good recovery rate can be obtained by using a short cone hydrocyclone. In a semi-industrial test of recovering copper and gold from tailings using hydrocyclones, a single enrichment of the total tailings using a short cone hydrocyclone can achieve a yield of 9%, copper grade of 0.18% to 0.25%, and gold grade of 0.08 to 0.16 g/t, with properties similar to the sediment of the original ore, and an enrichment ratio of 2.8 times.

3. Tailings filling

Tailings backfilling involves first dewatering the tailings to a concentration of approximately 70% tailings sand, then subjecting it to special treatment before reinjecting it into the mined-out mine. This is a backfilling method currently used in many mines.