Making oleophilic, buoyant, flowing, absorbent cellulosic granules capable of e.g. mopping-up oil spills on water

摘要

Moist fibrous material with 0.5%-25% resin and/or wax is comminuted. The feedstock is first compressed to a plug and internal pressure is raised to 60 bar. Rapid heating reaches 75 deg C, preferably 100 deg C. The process chamber is evacuated. Comminution follows, exerting shear stresses. Freshly-exposed surfaces, are pressure-coated with softened, partially-hydrated hydrophobic materials. The coating is rendered stable and homogenous by suitable machines, loosening up the product and drying to water content below 25%, preferably 15% or less.