Graphite Ore Dressing Processing Methods

Crystalline Graphite

Crystalline graphite products, primarily flake graphite, offer excellent flotation performance, with high yields of large flakes and high grade. Collectors and frothers, both commonly used in the beneficiation process, are both common and inexpensive. The flotation process has the following characteristics: First, during the flotation stage, because hard gangue minerals can significantly damage graphite flakes, a multi-stage flotation process is often employed. Tailings can be removed at the end of each stage, minimizing damage. Second, multiple concentration stages are crucial. Because the ore obtained from the re-concentration stage generally has a lower grade and does not meet national standards, multiple concentration stages are crucial. Furthermore, using multiple re-grinding stages simultaneously improves the separation of graphite crystals from other impurities and effectively preserves fully separated graphite crystals.

Cryptocrystalline Graphite

Crystalline graphite has very small particles, surrounded and embedded in clay. Similar to clay, it is powdery and difficult to separate. Therefore, the beneficiation process typically requires relatively large amounts of collectors and foaming agents, resulting in low beneficiation efficiency and difficult recovery. Cryptocrystalline graphite ore also typically contains organic matter, which can cause chemical reactions during flotation, making separation difficult.

Graphite Purification

Graphite products obtained after flotation and concentration generally have a grade exceeding 95%, but their flakes still contain numerous impurities, making purification even more challenging under these conditions. Current purification methods include chemical and high-temperature methods. Chemical methods, as the name suggests, utilize impurities to react with a separation gas to achieve separation. High-temperature separation methods utilize graphite's high-temperature resistance, allowing impurities to evaporate at temperatures of several thousand degrees Celsius, which graphite can withstand, thereby achieving graphite purification.

Graphite beneficiation process

(1) General beneficiation process for crystalline graphite

Different experimental processes directly affect product performance and production costs. Therefore, a reasonable flotation process is crucial to improving concentrate yield and grade. The characteristics of flake graphite in the flotation process are mainly reflected in the following two aspects: first, the large flakes must be protected from damage, and second, the graphite crystals and gangue minerals must be fully separated.

(2) General beneficiation process for cryptocrystalline graphite

The beneficiation process of cryptocrystalline graphite is relatively difficult. Characteristics such as small particle size and high organic matter content will affect the beneficiation process. Generally, hand selection is used, but the beneficiation efficiency of hand selection is low. In special cases, flotation process will be selected. Generally, tailings are not discarded to improve the recovery rate.