Because the density of the media in heavy media separation cannot be very high, and the feed particle size is coarse, heavy media separation is mainly used as a pre-selection process when processing dense metallic ores to remove low-density individual gangue or surrounding rock mixed in during the mining process. For example, ores such as lead-zinc ore and copper-sulfur ore, where the useful minerals are aggregated, produce a large amount of individual gangue after medium crushing. Heavy media separation can remove this gangue, preventing it from entering the grinding process. Surrounding rock mixed in weakly magnetic iron ore and manganese ore can also be removed using heavy media separation (note: waste rock mixed in magnetite is mostly removed using magnetic pulleys, not heavy media). Heavy media separation is also used in the beneficiation of low-grade rare metal ores and non-metallic ores. Furthermore, in coal preparation plants, heavy media separation is used to separate the briquettes from lump coal.

The application of heavy media separation requires that the mineral particles to be separated have suitable lower and upper particle size limits.

Because very small mineral particles, especially those with a density close to that of the heavy media, have very low settling velocities, the separation process is slow, and the separation efficiency is greatly reduced. Therefore, in industrial production, to ensure fast separation speed and high accuracy, the lower particle size limit is limited; the particle size cannot be too small. Thus, fine particles are often screened out before heavy media separation. Currently, the lower particle size limit for heavy media separation of metallic ores is generally 2–3 mm. If a heavy media hydrocyclone is used, the lower particle size limit can be reduced by 0.5 mm.

The upper limit of the feed particle size is mainly determined by the equipment conditions and the dispersing characteristics of the ore. For metallic ore beneficiation, it is generally 70–100 mm. Heavy media separation is currently commonly used to process ores with coarse-grained or aggregated dispersals.

Heavy media separation can remove a large amount of individual gangue, significantly reducing the amount of ore entering the next process, thereby increasing the production capacity of the concentrator and saving concentrator costs. Because of these advantages, heavy media separation is often used as a pre-selection process in metal ore concentrators.