Example of Nickel Ore Beneficiation
The Jinping Baimazhai Nickel Mine belongs to the kenex group. This mine…
(1) Quality requirements for chromium ore for metallurgical use
① Metallurgical chromium ore is classified into concentrates according to different processing methods (beneficiation and natural ore). (G) and block (K) Two categories. The concentrate is divided into 5 grades according to the different Cr₂O₃ contents, and its chemical composition should conform to the provisions of Table 4-28 .
Table 4-28 Grade and concentrate chemical composition (YB/T 5277—2005)
| Card Number | Chemical composition (mass fraction) | |||||
| Cr₂O₃ / % | Cr₂O₃/FeO | SiO₂/% | MgO/% | S/% | P/% | |
| ≥ | ≤ | |||||
| G-50A | 50.0 | 3.2 | 4.0 | 14.0 | 0.020 | 0.008 |
| G-50B | 3.0 | 6.0 | ||||
| G-50C | 2.5 | 6.0 | ||||
| G-48 | 48.0 | 2.5 | 8.0 | 14.0 | 0.020 | 0.008 |
| G-45 | 45.0 | 1.7 | 8.0 | 18.0 | 0.020 | 0.010 |
② Lump ore is divided into three grades according to the different Cr₂O₃ contents , and its chemical composition should conform to Table 4-29. Regulation.
Table 4-29 Grade and chemical composition of lump ore (YB/T 5277—2005)
| Card Number | Chemical composition (mass fraction) | ||||
| Cr₂O₃ / % | Cr₂O₃ / FeO | Al ₂ O ₃ /% | S/% | P/% | |
| ≥ | ≤ | ||||
| K-45 | 45.0 | 3.0 | 10.0 | 0.020 | 0.008 |
| K-42 | 42.0 | 2.8 | 12.0 | 0.020 | 0.008 |
| K-38 | 38.0 | 2.5 | 15.0 | 0.020 | 0.010 |
③ The moisture content of metallurgical chromium ore shall not exceed 10%.
④ The particle size of chromium ore for metallurgical use shall not exceed 300 mm .
⑤ No foreign matter is allowed to be mixed into metallurgical chromium ore.
(2) Quality requirements for chromium ore used in refractory materials The quality requirements for chromium ore used in refractory materials are shown in Table 4-30.
Table 4-30 Quality Requirements for Chromite Ore for Refractory Materials
| Taste class | Ore chemical composition /% | use way | ||
| Cr₂O₃ | SiO₂ | CaO | ||
| Grade A | ≥35 | ≤3 | ≤2 | Natural refractory materials |
| Grade II | 30～32 | ≤11 | ≤3 | Chrome bricks, chrome-magnesium bricks |
Note: Regardless of whether it is Grade I or Grade II, the ore size must be between 50 and 300 mm, and no ore larger than 5 to 8 mm is allowed. Clamped stones.
(3) Quality requirements for chemical grade chromium ore In the chemical industry, chromium ore is mainly used to directly produce dichromic acid. Salt is then used as a raw material to produce other chromium compound products. Its chemical composition requirements… Cr₂O₃≥30 %,
Cr₂O₃ / FeO ≥2 ～ 2.5, SiO₂ trace amount. General industrial indicators of chromite are shown in Table 4-31.
Table 4-31 General industrial indicators of chromite unit:%
| kind type | Cr₂O₃ | Average permissible content of harmful impurities | Concentrate ore content | ||||
| Boundary grade | Industrial quality | SiO₂ | P | S | |||
| Primary ore | Rich ore | ≥25 | ≥32 | ≤10 | ≤0.07 | ≤0.05 | |
| Low-grade ore | 5-8 | 8-10 | one | one | one | one | |
| Colluvial deposits (placer deposits) | ≥1.5 | ≥3 | one | one | one | >6 | |
Note: Minimum mineable thickness: 0.3–0.5 m for rich ore. 1 m of lean ore ; Thickness of interbedded rock removed: 0.3–0.5 m for rich ore. Lean ore: 0.5–1 m; Metallurgical Chromium ore or concentrate: Pyrometallurgical Cr₂O₃/FeO ≥ 2; Chromium ore or concentrate for refractory materials: SiO₂≤10 %, CaO≤3%, Fe₂O₃≤14%;
Chromium ore or concentrate for chemical use : SiO₂ ≤8%, Al ₂ O ₃ ≤15%.
(4) Quality requirements for cast stone grade chromium ore The chromium ore used to produce diabase cast stone has the following chemical composition requirements. Cr ₂O₃≥10% ～ 20%, SiO₂≤10 % In addition, chromium ore is also used in the foundry industry to produce chromium magnesite . Mineral products.