I'm hoping those of you out there with some graphite/geological knowledge may be able to give me an opinion on the results listed below. It is a saprolite deposit. All honest opinions would be greatly appreciated.
Table 1: Concentrates from High and Low-Grade Composites
Column 1
Column 2
Column 3
Column 4
Column 5
Column 6
Column 7
0
SizeFraction
High Grade Comp
Low Grade Comp
1
Mass
TC
LOI
Mass
TC
LOI
2
µm
%
%
%
%
%
%
3
500
28.4%
98.31
99.49
1.0%
98.52
99.04
4
300
21.3%
98.95
99.35
21.7%
98.52
99.04
5
180
15.4%
98.65
99.25
30.0%
98.92
98.63
6
150
6.6%
99.12
99.28
12.0%
97.29
98.36
7
106
7.0%
98.98
99.21
10.7%
97.11
98.44
8
75
6.0%
99.00
99.20
7.6%
98.17
98.31
9
-75
15.4%
96.53
96.27
17.0%
98.17
97.48
10
Calc Head
100.0%
98.37
98.88
100.0%
98.26
98.45
TC = Total Carbon by LECO, LOI = Loss on Ignition at 1000oC
The flotation test work, based on a standard graphite process flowsheet developed by IMO, demonstrated that coarse high purity graphite flakes can be produced from this standard flowsheet. Photos of +500 µm from the high-grade concentrate shown in Figure 1 reveal flake dimensions to be often in excess of 2 mm.
Figure 1: Micrographs of High Grade +500 µm Flake Graphite (picture 1 of 2)
Figure 1: Micrographs of High Grade +500 µm Flake Graphite (picture 2 of 2)
The process flowsheet included rougher flotation, followed by several regrind and cleaner flotation stages.
Flotation testwork based on IMO's standard graphite process flowsheet resulted in a high-grade concentrate from both low and high-grade composites as shown in Table 1 following.
High recovery of large flake (> 180 µm) was achieved from both high grade (65% mass) and low grade (53% mass) composites showing potential for recovery of high flake bearing premium concentrates throughout the deposit. Grades of each composite are as follows:
High Grade Composite Total Carbon Head Grade = 15.7%
Low Grade Composite Total Carbon Head Grade = 2.6%
