The low-temperature belt dryers with RecuDry® heat recovery technology from STELA Laxhuber, Massing/Germany, have been a successful model for years. More than 50 systems with RecuDry® technology have been commissioned by the Lower Bavarian company in recent years as part of new construction or replacement investments in pellet plants.
A recent example is the pellet plant at the Josef Ziegler sawmill and planing mill in Stein near Plößberg/Germany, which went into operation in the summer. A type 3002 belt dryer equipped with RecuDry® Advanced technology was installed there, which requires around 50% less thermal energy than a comparable standard dryer. ‘This is a very energy-efficient drying process. Thanks to the extremely low waste heat level (50 to 60°C), we can use RecuDry technology at its highest level,’ says Tobias Latein, sales manager at STELA Laxhuber. Another advantage is that the exhaust air from pellet production is used to generate energy in the belt dryer. Thanks to a special STELA-Laxhuber solution, the belt dryer can also serve as a filter.
In the STELA RecuDry® system, the proven drying technology is divided into two modules: the RecuDry® module and the condensation module. In the RecuDry® module, the drying air is optimally enriched with moisture through recirculation and reheating. The resulting high-energy air is used in the condensation module to heat the fresh air. The use of an air-to-air heat exchanger recovers a large part of the energy used, enabling particularly efficient drying. The preheated process air is then brought to the required drying temperature via a water-glycol circuit. The belt speed or throughput time of the 3 m wide belt varies depending on the moisture content. "Our belt dryers are customised to suit any space requirements. In the case of the Josef Ziegler sawmill, we had to integrate the belt dryer into an existing sawmill with very limited space. We were responsible for the project planning, installation and commissioning of the belt dryer. We also supplied the control system for the dryer and pelletising," emphasises Latein.
Author/credits: Matzku Phillip, Belt dryer with 50% energy savings, Holzkurier, issue 44 2025
