XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3483
cycloning stages is sent to a thickener. Depending on the
thickener technology applied, the flowsheet can achieve
very high-water recovery rates. The thickener underflow is
pumped either to the TSF for storage or further thickened
to produce paste tailings.
The Cavex ® DE hydrocyclone, used for the primary clas-
sification, produces the stream represented by stream 2 in
Figure 6. This stream can be used either as sand fill for dam
construction (stream 2b) or as feed for further classification
(stream 4). An indicative mass balance is given in Table 6.
The combination of applied technologies makes this
flowsheet well-suited for large scale operations in moder-
ate climates. The application of self-draining sands favors
long term stability as it maintains the draining capacities of
the stack. This improved drainage capacity increases over-
all water recovery and helps maintain safe saturation levels
within the dam.
1 3
Fresh Tailings
Water 9
Water
2
4
5
6
7
8
10
11
2b
Figure 6. Proposed flowsheet using Cavex® DE hydrocyclone with sands reclassification
Table 6. Operational data balance of Cavex® DE hydrocyclone with sands reclassification
Tailings Flowsheet
Option N°4
1
Fresh
Tailings
2 and 2b
Cavex® DE
Hydrocyclone
Sands
3
Cavex® DE
Hydrocyclone
Fines
4
Cavex® DE
Hydrocyclone
Feed
5
Cavex® 2
Hydrocyclone
UF
6
Cavex® 2
Hydrocyclone
OF
7
Thickener
Feed
8
Thickener
UF
9
Thickener
OF
Solid Flow t/h 3,000 1,350 1,650 1,350 1,080 270 1,920 1,920 0
Solid Flow m3/h 1,111 500 611 500 400 100 711 711 0
Liquid Flow t/h 5,571 474 5,097 1,350 420 930 6,027 1,571 4,456
Liquid Flow m3/h 5,571 474 5,097 1,350 420 930 6,027 1,571 4,456
Slurry Flow t/h 8,571 1,824 6,747 2,700 1,500 1,200 7,947 3,491 4,457
Slurry Flow m3/h 6,683 974 5,708 1,850 820 1,030 6,738 2,282 4,456
Cw [%]35.0 74.0 24.5 50.0 72.0 22.5 24.2 55.0 0.0
Cv [%]16.6 51.3 10.7 27.0 48.8 9.7 10.6 31.2 0.0
S.G. Solid t/m3 2.70 2.70 2.70 2.70 2.70 2.70 2.70 2.70 2.70
Liquid Density t/m3 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00
Slurry Density t/m3 1.28 1.87 1.18 1.46 1.83 1.17 1.18 1.53 1.00
Make-Up m3/t 0.26
Water Recovery [%]70%
cycloning stages is sent to a thickener. Depending on the
thickener technology applied, the flowsheet can achieve
very high-water recovery rates. The thickener underflow is
pumped either to the TSF for storage or further thickened
to produce paste tailings.
The Cavex ® DE hydrocyclone, used for the primary clas-
sification, produces the stream represented by stream 2 in
Figure 6. This stream can be used either as sand fill for dam
construction (stream 2b) or as feed for further classification
(stream 4). An indicative mass balance is given in Table 6.
The combination of applied technologies makes this
flowsheet well-suited for large scale operations in moder-
ate climates. The application of self-draining sands favors
long term stability as it maintains the draining capacities of
the stack. This improved drainage capacity increases over-
all water recovery and helps maintain safe saturation levels
within the dam.
1 3
Fresh Tailings
Water 9
Water
2
4
5
6
7
8
10
11
2b
Figure 6. Proposed flowsheet using Cavex® DE hydrocyclone with sands reclassification
Table 6. Operational data balance of Cavex® DE hydrocyclone with sands reclassification
Tailings Flowsheet
Option N°4
1
Fresh
Tailings
2 and 2b
Cavex® DE
Hydrocyclone
Sands
3
Cavex® DE
Hydrocyclone
Fines
4
Cavex® DE
Hydrocyclone
Feed
5
Cavex® 2
Hydrocyclone
UF
6
Cavex® 2
Hydrocyclone
OF
7
Thickener
Feed
8
Thickener
UF
9
Thickener
OF
Solid Flow t/h 3,000 1,350 1,650 1,350 1,080 270 1,920 1,920 0
Solid Flow m3/h 1,111 500 611 500 400 100 711 711 0
Liquid Flow t/h 5,571 474 5,097 1,350 420 930 6,027 1,571 4,456
Liquid Flow m3/h 5,571 474 5,097 1,350 420 930 6,027 1,571 4,456
Slurry Flow t/h 8,571 1,824 6,747 2,700 1,500 1,200 7,947 3,491 4,457
Slurry Flow m3/h 6,683 974 5,708 1,850 820 1,030 6,738 2,282 4,456
Cw [%]35.0 74.0 24.5 50.0 72.0 22.5 24.2 55.0 0.0
Cv [%]16.6 51.3 10.7 27.0 48.8 9.7 10.6 31.2 0.0
S.G. Solid t/m3 2.70 2.70 2.70 2.70 2.70 2.70 2.70 2.70 2.70
Liquid Density t/m3 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00
Slurry Density t/m3 1.28 1.87 1.18 1.46 1.83 1.17 1.18 1.53 1.00
Make-Up m3/t 0.26
Water Recovery [%]70%