What this application covers
Coal washing plants — also called coal preparation plants — clean raw run-of-mine coal by removing rock, shale, and other non-coal material to produce a saleable product at the required ash, moisture, and size specification. A typical plant routes feed through raw-coal handling, sizing, dense-medium and water-based cleaning, dewatering, and tailings management. Each section has its own equipment scope, and the integration points between sections — surge capacity, transfer chutes, water and medium balance — are where most engineering effort is focused.
Step by step
Raw coal feed and sizing
Run-of-mine coal is received, broken to a manageable top size, and screened into size fractions matched to the cleaning circuits.
Coarse coal cleaning
Coarse fractions are cleaned by dense-medium baths or vessels, or by jigs, separating clean coal from rejects.
Fine coal cleaning
Fine fractions are cleaned by dense-medium cyclones, spirals, teeter-bed separators, or flotation.
Dewatering
Cleaned coal is dewatered on screens and centrifuges; ultra-fine product on filter presses if recovered.
Medium and water recovery
Dense medium (magnetite) is recovered by wet drum magnetic separators; process water is clarified and recycled.
Tailings management
Tailings are dewatered by filter press, thickener, or paste plant for stackable or pumpable disposal.
Technical Buying Considerations
Equipment buying decisions for coal washing plants are driven by feed coal characterization (size distribution, washability, contaminant types), required product specification, water balance, and tailings disposal route. Capital decisions usually involve trade-offs between fines recovery and tailings volume reduction; both sides should be evaluated together rather than as isolated equipment purchases.