Operational Efficiency Transformation at Holzindustrie Hassel with STELA Drying Technology

by | Mar 20, 2024


New management at Holzindustrie Hassel aimed to enhance the efficiency and the operational stability of their sawmill  facility with the integration of a pellet plant. This strategic move was designed to diversify their operations and optimize the use of byproducts. A critical requirement for this expansion was to implement a smart drying solution capable of effectively reducing the moisture content in the byproducts.

The success of this integration hinged on finding a technology that not only dried the materials efficiently but also worked in harmony with the biomass boiler planned for the facility. The drying solution needed to ensure that the byproducts were sufficiently dry to produce high-quality pellets.


The transformation at Holzindustrie Hassel was marked by the integration of a holistic plant layout, central to which was a compact STELA Dryer Type BTU RecuDry. This comprehensive system included a silo for wet chip storage, a sophisticated hot water boiler system fueled by sawmill residues like bark, and a state-of-the-art low temperature drying process powered by the boiler’s thermal energy.

The STELA BTU RecuDry 1/6200-18 belt dryer, with a processing length of 60 feet and the capability for future extension to 120 feet, became the linchpin of this setup. Designed for remarkable energy efficiency, the dryer uses an advanced air-to-air heat recovery system, reducing energy consumption by 35-55% compared to traditional systems and lowering emissions. This efficiency is highlighted by its specific energy use of 720 kW/mt (2.2MMBTU/st) for water evaporation, significantly enhancing the plant’s sustainability profile.

Overview of the Holzindustrie Hassel sawmill + pellet mill integration.


Through the integration of the STELA low temperature belt drying technology, Holzindustrie Hassel achieved a substantial leap in operational efficiency. The byproducts enter the dryer with a moisture content of approximately 50% and exit at an optimal 10%. The process not only stabilized pellet production, increasing product quality, but also strategically eliminated byproduct management problems through the seamless integration of wet silos and the integrated pellet plant. Furthermore, the installation of dry silos acted as effective buffers, allowing for maintenance activities without halting production, thereby ensuring a continuous and efficient workflow. Remarkably, the entire build-out of the plant, from concept to the start of pellet production, was completed in a span of just 13 months.


The Holzindustrie Hassel case study exemplifies how pellet plant integration with low temperature belt drying technology can greatly enhance sawmill operations. By adopting the STELA Dryer Type BTU RecuDry, Holzindustrie Hassel achieved very consistent drying results while enhancing its production efficiency and sustainability. This success story demonstrates the potential for similar facilities to optimize their operations, showcasing STELA’s role in delivering cutting-edge, energy-efficient solutions to the wood processing industry.



About Holzindustrie Hassel

With a heritage spanning over a century, Holzindustrie Hassel is driven by a profound passion for wood – a sustainable and adaptable resource. The company excels in crafting a broad array of wood products, from sawn timber to custom solutions and high-quality pellets, securing its position as a trusted partner for mid-sized businesses. Holzindustrie Hassel, is synonymous with innovation, quality, and dependability.