Today, anyone who produces wood pellets must consider much more than just the raw material. Energy efficiency, sustainability, robust processes, flexible material flows, and automated plant operation are all becoming increasingly important. Many companies are therefore faced with the same question: How can production be set up so that it works technically and remains economically viable in the long term? It is a question that Ennstal Pellets asked itself and answered with our help.
Ennstal Pellets relied on a classic ring die plant for a long time. The plant incurred high energy costs, required additional dry grinding, and was also located 45 km away from the sawmill, making it logistically impractical and unsustainable. Therefore, it was clear to the management that a new solution was needed. The requirements were that it be compact and energy-efficient and located directly at the sawmill site.
Ennstal Pellets achieved this step by switching to Amandus Kahl's flat die technology. The new plant has been fully integrated into ongoing operations and now enables the energy-optimized production of domestic fuel pellets for the regional market.
Flat die as the key to efficient wood pelleting
The biggest advantage of flat die technology is that dry grinding is no longer necessary. While the old plant required an additional crushing step, the new pellet mill processes dried sawdust directly, reducing energy consumption by up to 35 kWh per ton. Additionally, this technology offers several other efficiency advantages:
- Less space is required thanks to the compact design.
- Simplified integration into existing plants.
- Less maintenance is required thanks to the robust technologys.
- Lower investment and operating costs thanks to efficient processes.
Together, these features ensure a consistently efficient production process. The dried sawdust is stored temporarily in the dry chip silo before being transported to the screen via a discharge system. There, splinters are removed, and impurities and foreign matter are separated using the heavy-particle separator. A belt weigher continuously records the product flow, providing accurate data for operation and internal calculations. An online moisture measurement system measures the moisture content of the product continuously. If the wood material lacks sufficient binding properties, starch can be added upstream of the mixing conditioner. The optional automatic addition of water helps achieve an ideal pellet moisture content of approximately 10 to 12%. After a retention time in the agitator bin, during which the added water is absorbed until the product is fully saturated, the product is fed into the mixing screw via a dosing screw with a frequency converter. Water can also be added here if necessary. Then, the product is fed into the KAHL flat die pellet mill. The result is high-quality ENplus pellets, which are kept at a consistent quality in the connected cooler and concrete pellet silo.
Machines for the cycle: Zero waste wood pelleting
Another advantage is the complete utilization of raw materials. The fines produced during the process are separated by a rope-and-pulley conveyor, then returned to the dry chip silo to be reprocessed. This means that no waste is produced.
“It was important to us to implement a solution that is truly sustainable. The fact that we can reuse all residual materials in the process provides clear ecological and economic advantages,” explains Rupert Klausbauer, Managing Director of Ennstal Pellets.
In addition, the specially configured grinding plant can process dry oversized material and splinters, as well as wet wood chips. This increases flexibility in the use of materials and enables consistent, efficient use of all wood components – in line with the zero-waste principle.
Smart technology for maximum energy savings
Technologically, the new plant is also in a league of its own. The electronic automatic pellet mill regulation system (EAPR) is the focus. It monitors all process parameters and precisely controls operation. Two additional systems contribute significantly to energy and cost efficiency:
- Distamat: The automatic roller gap control unit ensures consistent pellet quality by continuously monitoring and adjusting the roller gap during operation.
- Eco Roll technology: The Eco Roll is highly energy-efficient, reducing consumption to only 40 to 45 kWh per ton of softwood. It also offers several additional advantages, including less wear and tear, a longer service life, and up to 25% more production capacity.
A true partner in machinery
Amandus Kahl designed the complete plant and installed it during ongoing operations. This means greater efficiency, more reliable planning, and a stable production base for the future for Ennstal Pellets.
“With the new plant, we are saving on transport routes and gaining efficiency and planning reliability,” summarizes Rupert Klausbauer. “In addition to the technology, cooperation was particularly important to us. Amandus Kahl provided competent, customer-oriented advice, and we feel very well supported by their customer service. This gives us the security to move forward with a reliable partner.”
