Less air, more wood: Liebherr shreds waste wood directly on-site
The Liebherr facility in Nenzing generates 350 to 400 metric tons of waste wood annually. To process this material efficiently, WEIMA supplied a customized system solution consisting of a shredder, conveyor technology, and dust extraction. A WEIMA WLK 1500 single-shaft shredder shreds the bulky packaging and dunnage wood before it is removed. AL-KO designed a solution tailored specifically to this application to ensure safe and clean dust extraction. The project demonstrates how collaboration between strong partners results in a high-performance, comprehensive solution.
WEIMA WLK 1500 Single-Shaft Shredder with AL-KO Extraction System at Liebherr
Waste wood generated during production and delivery
Liebherr-Werk Nenzing GmbH in Vorarlberg manufactures machinery for specialized civil engineering, hydraulic cable excavators, and crawler cranes. Many supplied components arrive at the plant on wooden pallets or in wooden packaging. Even within the production area, wooden shims protect painted surfaces and components from direct contact with the floor. After use, the material is often no longer needed. As a result, the site generates approximately 350 to 400 metric tons of waste wood annually.
Bulky wood scraps result in high transportation costs
In the past, wood scraps were simply disposed of as-is in waste containers. There was a lot of empty space between the large, bulky pieces, so the available container volume was not fully utilized. This resulted in frequent pickups and high transportation costs. For Jürgen Wachter, Head of Industrial Engineering and Project Manager for the wood shredding plant, the solution was clear: “We then came to the decision that a shredding plant would allow us to reduce transportation costs while also contributing to CO₂ savings.”
Compact Shredding and Extraction in a Confined Space
The project had to take two key constraints into account: Space was limited, and Liebherr required a coordinated safety and explosion protection plan.
At the heart of the system is a A WEIMA WLK 1500 single-shaft shredder. Wood scraps are first collected in bins in the workshops. A forklift regularly transports them to the system and tips the material directly into the feed hopper. After shredding, the wood chips are transported to a container via a screw conveyor from Steiner GmbH & Co. KG. A metal separator reliably removes nails and other metallic foreign objects from the material stream. Larger pieces of wood are retained by the 50-mm screen mesh, resulting in wood chips of a more uniform size.
Less air in the container
Shredding significantly reduces the volume of the material, thereby allowing for much more efficient use of the container. Instead of bulky pieces of wood with large air pockets, the container can now be filled compactly and almost completely with wood chips. The shredded material contains no unwanted fine particles and very little dust.
Effective dust extraction at two locations
Fine dust is generated during every shredding operation. An AL-KO extraction system keeps the surrounding area clean and helps prevent the formation of an explosive atmosphere. The POWER UNIT 250 extraction system, with a maximum airflow rate of 4,900 m³/h, captures the dust at two points. A circumferential extraction ring, developed in collaboration with WEIMA, is located at the feed hopper. A second collection point is situated at the material discharge point above the container. The extracted chips and dust are collected in a container. Since this is purely a waste product, the dust can be sent for recycling as usual.
The collaboration went very well, even though there were many details to work out beforehand. WEIMA coordinated the various departments and partners involved. Today, we have a very compact system here that works perfectly. We’re very pleased with it
A Coordinated Comprehensive Solution
Implementing the project required collaboration among several companies and departments. The result is a compact system that fits into the limited space available and meets the required safety standards.
Since the system went into operation this year, Liebherr has been shredding the waste wood generated directly on-site. The reduction in volume allows for more efficient use of transport containers. The number of required pickups and the associated costs are decreasing. Instead of simply disposing of the wood, the wood chips produced are sold and put to new use—including as a raw material for the production of new particleboard.