Tungsten Ore Beneficiation Process

Tungsten ore mainly includes wolframite, scheelite, and spodumene-wolframite ore. Although all are tungsten ores, their beneficiation processes differ. Currently, the grade of global tungsten ore is decreasing year by year, and easily mined and beneficiated wolframite is becoming increasingly scarce, while difficult-to-process scheelite and spodumene-wolframite ore are gradually taking center stage. How to beneficiate scheelite? How to beneficiate wolframite? Wolframite is easy to beneficiate and is mostly processed using gravity separation. Scheelite is relatively more difficult to beneficiate, and processes include gravity separation and flotation. Different raw ores require different equipment. Recommended beneficiation equipment for scheelite and ferruginous tungsten ore is as follows:

Scheerungsten Ore - Gravity Separation, Flotation

Coarse-grained Scheelite - Gravity Separation, Flotation

Key Separation Techniques: Achieving high recovery rate and high-quality tungsten concentrate

Scheerungsten Ore Beneficiation Equipment Process Flow:

1. During coarse grinding, xanthate-based collectors are added to float various sulfides;

2. In the gravity separation stage, shaking table separation is used to obtain a portion (or all) of qualified tungsten concentrate;

3. The gravity separation tailings are floated with oleic acid-based collectors to obtain a crude concentrate containing 10%-25%, which is then sent for hydrometallurgical treatment.

Recommended beneficiation equipment for coarse-grained scheelite: Wet grate ball mill, linear vibrating screen, 6S shaking table, XCF type flotation machine.

Fine-grained scheelite - Gravity separation and flotation processes

Key beneficiation stages: Roughing and cleaning stages

Roughing stage - Maximizes the grade of the rough concentrate

Cleaning stage - Separates calcium-bearing gangue minerals from scheelite to obtain qualified tungsten concentrate.

Fine-grained scheelite processing flow:

1. Use sodium sulfide, cyanide, chromate, etc. to suppress associated sulfide minerals; use water glass, tannin, sodium polymetaphosphate, chromate, etc. to suppress gangue minerals. Then adjust the pH of the pulp to 9.5-10 with water glass or sodium carbonate, and 11-12 for cleaning;

2. Use the "lime-flotation" method. Adjust the pulp with lime, add sodium carbonate and water glass, and finally collect with oleic acid and naphthenic acid;

3. Use a large-volume water glass heating cleaning method, that is, add a certain amount of water glass to the low-grade rough concentrate, heat, cook, stir, dewater, adjust the pulp, and then clean multiple times to obtain a higher-grade tungsten concentrate.

Recommended fine-grained scheelite beneficiation equipment: Straight-cylinder energy-saving overflow ball mill, SF type flotation machine, JJF type flotation machine, high-efficiency stirred tank.

Wollastonite - Gravity Separation Process

Key Separation Techniques: Early jigging, shaking table tailings rejection

Wollastonite beneficiation equipment process flow:

1. Roughing: In the first stage of the fine-grained stage of the roughing section, a jig is used, followed directly to the cleaning operation.

2. Gravity Separation: A multi-stage jig, multi-stage shaking table, and middlings regrinding gravity separation process is adopted.

After fine crushing, qualified ore is classified by a vibrating screen and then subjected to multi-stage jiging to produce jig gravity separation raw sand. The coarse-grained jig tailings are regrinded in a mill, while the fine-grained jig tailings are classified and then subjected to multi-stage shaking table separation to produce shaking table gravity separation raw sand. The shaking table tailings are discharged into the tailings dam, the shaking table middlings are returned for regrinding and re-separation, and the jig and shaking table gravity separation raw sand enters the cleaning operation.

Fine Separation: Multiple separation processes, including combined flotation-gravity or combined flotation-gravity-magnetic separation, are employed, with associated elements recovered in the fine separation stage.

Sulfide ores are removed through coarse and fine flotation (a combination of flotation and shaking table beneficiation) and mechanical flotation. The flotation- and mechanically flotated sulfide ores are combined and then separated through sulfide ore flotation. The flotation- and mechanically flotated wolframite is further separated by gravity separation to produce wolframite concentrate. If the wolframite concentrate contains scheelite and cassiterite, these are separated into wolframite concentrate, scheelite concentrate, and tin concentrate through gravity flotation or a combined gravity flotation-magnetic separation process.

Fine Sludge Treatment: Xinhai typically performs desulfurization first, and then, depending on the properties of the fine sludge material, recovers tungsten minerals through gravity separation, flotation, magnetic separation, electrostatic separation, or a combination of several processes, while simultaneously utilizing associated metal minerals.

Recommended Wolframite Beneficiation Equipment: Self-centering vibrating screen, 6S shaking table, jig, SF type flotation machine.

Wolf-scheelite and scheelite coexisting ores - High-intensity magnetic separation and flotation processes

For coexisting smelt and scheelite ores, especially fine-grained polymetallic ores with smelt and scheelite intergrowth, a mixed flotation process is typically used for recovery.

Key beneficiation step: Separating scheelite and wolf-scheelite from coexisting complex polymetallic ores.

Process flow for wolf-scheelite coexisting ores:

1. Mixed flotation of sulfide ores - mixed flotation of wolf-scheelite and scheelite - heated cleaning of scheelite - high-intensity magnetic separation of scheelite tailings - gravity separation of wolf-scheelite;

2. Mixed flotation of sulfide ores - high-intensity magnetic separation of wolf-scheelite and scheelite - flotation of scheelite - flotation of wolf-scheelite.