Rotary drum dryer Indirect

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GRELBEX indirect rotary kilns allow for the industrial calcination of all powdered solids by indirectly exposing them to hot gases. They are designed for reliable operation, low maintenance, maximum efficiency, and high industrial availability. These performance criteria make our rotary dryers a wise choice for drying powdered solids. OPERATION Indirect rotary kilns consist of a cylinder (drum ) that rotates slowly and steadily on two supports (belts). This cylinder is driven by an electric or hydraulic motor. The cylinder is enclosed in a casing that heats the calender either with a flame or by circulating hot air within the casing. As the drum rotates, the product advances and comes into contact with the hot surface of the calender. As it is agitated, it loses its moisture. In this specific case, the drying process can be carried out under oxidizing, reducing, or inert conditions. These kilns are suitable for varying throughputs (from hundreds of kg to several tens of tons per hour) with relatively high processing temperatures (from 300 to over 1600°C) and can handle solids with fairly fine particle sizes. They are particularly well-suited for processing mineral materials, plant-based materials, or fragile products. It is important to optimize this equipment. Numerous options exist for partially recovering energy from the drying airflow after the process (partial recycling, condensation, cooling, separation, etc.). APPLICATIONS: Chemical Industry • Calcination of carbonates, sulfates, or hydroxides • Thermal decomposition of air-sensitive or flue gas-sensitive compounds. • Controlled solid-gas reactions: for example, reduction, sulfation, or selective oxidation. • Catalyst processing: activation, regeneration, or drying of catalytic supports. Fine Chemicals Industry • Drying of heat-sensitive powders or granules without contamination. • Pyrolysis for the production of organic intermediates. • Devolatilization of high-purity polymers or resins. Energy Recovery • Pyrolysis of industrial waste, sludge, or biomass to produce usable gases and charcoal. • Carbonization of organic materials (activated carbon, biochar, etc.). • Thermal neutralization of hazardous residues (without direct emission of harmful gases). • Pilot-scale pyrolysis, gasification, or calcination processes. Materials Industry (ceramics, cement, glass, etc.) • Precalcination of fine raw materials sensitive to contamination. • Heat treatment of advanced ceramic powders (Al₂O₃, SiC, TiO₂…).