Wolframite, an important strategic tungsten resource, is characterized by its brittleness, susceptibility to over-grinding, and concentrated fine particle size distribution. Traditional gravity separation and flotation processes suffer from poor recovery efficiency and significant metal loss in fine-grained wolframite. To address the challenge of efficient recovery of wolframite (especially fine tungsten slime), an experiment was conducted using an SLon Vertical Ring Pulsating High Gradient Magnetic Separator(VPHGMS) to verify the equipment’s adaptability and technological advantages in separating weakly magnetic wolframite.
I. Experimental Materials and Property
The experimental mineral sample is fine wolframite mud, with a WO3 grade of 0.25% after desulfurization. The tungsten phase is dominated by wolframite, accounting for 82.10%, while scheelite accounted for 16.72%. The particle size distribution is concentrated, with 90.78% of the tungsten metal content distributed in the -0.05mm fine-grained range, indicating a high degree of mudification.
|
WO3 |
Mo |
Cu |
Pb |
Zn |
S |
Al2O3 |
SiO2 |
CaO |
|
0.25 |
0.022 |
0.005 |
0.04 |
0.007 |
0.11 |
6.97 |
71.28 |
2.54 |
Table 1 Results of chemical analysis
|
Phase |
Wolframite |
Scheelite |
Tungsten Ochre |
Total |
|
Content/% |
0.1965 |
0.04002 |
0.00282 |
0.23934 |
|
Distribution Rate/% |
82.10 |
16.72 |
1.18 |
100.00 |
Table 2 Analysis results of tungsten phase
|
Particle Size/mm |
Yield/% |
WO3 Grade /% |
WO3 Distribution Rate / % |
|
+0.154 |
8.97 |
0.01 |
0.38 |
|
−0.154+0.076 |
28.90 |
0.036 |
4.45 |
|
−0.076+0.05 |
23.86 |
0.043 |
4.39 |
|
−0.05+0.038 |
9.48 |
0.19 |
7.70 |
|
−0.038+0.03 |
5.70 |
0.41 |
10.00 |
|
−0.03 |
23.09 |
0.74 |
73.08 |
|
Total |
100.00 |
0.23 |
100.00 |
Table 3 Analysis results of particle size distribution
II. Experimental Equipment and Process
Core experimental equipment: SLon VPHGMS and rapid micro-shaking table
III. Experimental Methods
The experiment employed a combined magnetic separation and gravity separation process:
1.Coarse particles arefirst removed using a cylindrical slag screen to avoid interfering with the separation;
2.Roughing isperformed using a SLon VPHGMS to recover weakly magnetic wolframite;
3.The magnetically separated rough concentrates are then subjected to secondary cleaning on a rapid micro-shaking table to improve the concentrate grade.
IV. Experimental Results
1.Small-scale laboratory experiment: Iron concentrate (tungsten concentrate); WO3 grade 37.53%; recovery rate 58.65%;
2.Industrial commissioning experiment: Tungsten concentrate; WO3 grade 33.63%;recovery rate 56.51%;
Among them, the SLon single-stage roughing magnetic separation operation can obtain a rough concentrate with a WO3 grade of 1.37% and a recovery rate of 80.54%, showing outstanding recovery effect on fine-grained wolframite.
V. Experimental Conclusions
1. The SLon VPHGMS has a strong capture capability for fine-grained weakly magnetic wolframite, whichis stable and reliable;
2. The combined magnetic separation and gravity separation process can significantly improve the recovery index of wolframite slime, and the concentrate grade and recovery rate are far superior to those of the single gravity separation process;
3. This equipment has advantages such as large processing capacity, strong adaptability, and resistance to clogging, and is suitable for industrial separation experiments and production applications of wolframite and tungsten slime.
