Graphite ore is divided into earthy graphite ore and flake graphite ore. Earthy graphite, also called aphanitic graphite ore, features small graphite crystals with a dull, earthy surface and relatively poor industrial performance. While the raw ore grade is typically high (60-80%), its flotation-ability is poor, with minimal grade improvement after flotation. Ores with less than 65% grade are generally not mined, while grades between 65-80% can be used after sorting.

Flake graphite ore contains graphite in scale or leaf shapes with lower raw ore grades (typically 3-5%, maximum 20-25%). This type has excellent flotation-ability, reaching over 90% grade after processing, making ores with just 2-3% grade viable for mining. Flake graphite's superior properties make it ideal for high-grade carbon products. Selection criteria should consider both ore grade and type when determining flotation suitability.

The beneficiation production line for amorphous graphite ore typically includes:

• Coarse crushing: Primary crushing using jaw crushers
• Medium and fine crushing: Hydraulic cone crushers and hammer crushers
• Grinding: Ball mills and specialized grinding equipment
• Flotation: SF-type and XJK-type flotation machines
• Dehydration: Dehydration screens, centrifugal dehydrators, and filters
• Classification: Spiral classifiers for effective graphite classification
• Drying: Industrial dryers for final processing

With medium-hard to soft graphite ore (typically 2-10% grade), crushing processes are simplified, often using three-stage, two-stage, or single-stage open circuit systems. Weathered ores from small/medium mines may bypass crushing for direct ball mill processing.

Flotation typically employs multi-stage closed-circuit processes with concentrate regrinding achieving ~80% recovery rates. While some operations test middling ore regrinding, results remain inconclusive. Smaller facilities using open/semi-open flotation processes often see reduced recovery rates (40-50%) due to excessive waste tailings points.

While aphanitic graphite ore has high grade, its complex sorting requires specialized methods including flotation (most common), electric separation, and gravity separation. Flotation performance excels with scale graphite, using kerosene/diesel as collectors and No. 2/4 oil as foaming agents in China. International operations may incorporate additional agents like heavy oil, petroleum derivatives, or specialized esters, sometimes in combination.

• Compact, high-end equipment layout minimizes footprint and civil construction costs
• High automation with remote computer control reduces labor/material investments
• Safe, stable operation with ultra-low failure rates and minimal environmental impact
• Concentrate grade improvements up to 10 percentage points enhance industrial value

Standard configurations include jaw crushers for coarse crushing (crystalline/amorphous ores), cone/hammer crushers for medium/fine crushing, wet/grid ball mills, JJF/XCF/XJB flotation machines, and hydrocyclones/belt filters for dehydration.