The process of hydraulic transport through pipelines, world-wide well known for the trans- port of fine-grain solids is also being used to a greater extent in mining for the handling of 1rimarily coarse-grain solid - water mixtures r the removal of, for instance Coal and waste mixtures after coal winning rising hydraulic monitors, lings for backfilling underground and :her tailings and flotation waste to A large-scale test unit was taken into service at the Bergbauforschung GmbH (Mining P',search Company) in Essen-Kray, GFR, to urther improve this technology. The unit was :fanned and built by Krupp Industrie- and +hibau of Duisburg in cooperation with i r<1 auforschung gmbh. the paper deals in detail with the demands -)n this test unit and the technical results ltained on it and with the planned experimental>