Autogenous Mill
Working Principle of an Autogenous Mill The grinding process of an autogenous…
In several lead‑zinc flotation tailings sites in western and northern Guangdong Province, spiral chute gravity separation is used to recover pyrite from the tailings. The mineral composition, single‑mineral analysis of pyrite, multi‑element analysis, and sieve analysis of the lead‑zinc flotation tailings from northern and western Guangdong are shown in Tables 4‑49 to 4‑52, respectively.
Table 4‑49 Mineral composition
| Northern Guangdong lead‑zinc tailings | Western Guangdong lead‑zinc tailings |
|---|---|
| Pyrite with small amounts of galena and sphalerite | Pyrite with small amounts of lead‑zinc minerals, hematite, and limonite |
| Gangue minerals mainly sericite, quartz, calcite, chlorite, with minor dolomite, etc. | Gangue minerals: quartz, feldspar, kaolin, sericite, dolomite, calcite, etc. |
Table 4‑50 Single‑mineral analysis of pyrite from northern Guangdong (%)
| Component | S | Fe | Pb | Zn | Cu | Total |
|---|---|---|---|---|---|---|
| Mass fraction | 52.73 | 43.35 | 0.49 | 0.071 | 0.005 | 96.85 |
Table 4‑51 Multi‑element analysis of northern Guangdong lead‑zinc tailings (%)
| Component | S | As | SiO₂ | Al₂O₃ | CaO | Ag (g/t) |
|---|---|---|---|---|---|---|
| Mass fraction | 30.5 | 0.21 | 16.33 | 2.80 | 7.21 | 64.0 |
Table 4‑52 Sieve analysis results
| Particle size fraction/mm | the northern part of Guangdong Province | the western part of Guangdong Province | ||||
| 产率/% | 品位/% | 分布率/% | 产率/% | 品位/% | 分布率/% | |
| +0.2 | 7.06 | 14.85 | 3.73 | 一 | 一 | |
| -0.20+0.10 | 27.00 | 23.22 | 22.31 | 7.16 | 2.32 | 0.71 |
| -0.10+0.076 | 12.25 | 33.54 | 14.62 | 30.18 | 14.37 | 18.68 |
| -0.076+0.043 | 18.87 | 35.92 | 24.12 | 24.55 | 31.85 | 33.68 |
| -0.043+0.030 | 6.08 | 38.85 | 8.41 | 17.65 | 32.85 | 24.96 |
| -0.030 | 28.74 | 26.21 | 26.81 | 20.46 | 24.93 | 21.97 |
| 合 计 | 100.00 | 31.46 | 100.00 | 100.00 | 23.22 | 100.00 |
Through testing, a single pass of the lead‑zinc tailings through a spiral chute (process flow shown in Figure 4‑33) yields a pyrite concentrate with a grade of 39.75%–44.80% and a recovery of 58%–74%.
Figure 4‑33 Process flow of spiral chute separation
