Developing an ATEX Process in Record Time

Solution conveys dusty peat pellets

3 Min Read
One of two repurposed potato wagons backing up against the pellet hopperImage courtesy of WWTec GmbH & Co. KG

When the request from Finland for handling peat pellets was received, WWTec GmbH & Co. KG (Germany) already had a full schedule for the entire calendar year. Of course, the project opportunity was still discussed to find the desired solution in consultation with the customer, who uses the pellets in an innovative way to manufacture eco-friendly activated carbon for air and water purification.

The peat pellets were to be conveyed from a storage hall to a reactor 300 m away. Normally, this is done via a pneumatic conveying line. However, a standby solution was still needed for downtime and maintenance work. It quickly became clear that a new machine could not be built for the desired process; the time objective and the personnel resources were simply too tight. In addition, at that time an extreme backlog in the supply chains due to COVID and other global crises led to unprecedented waiting times for standard components.

Many companies would probably have turned down this opportunity. The team at WWTec, however, has a gift for "inventing" solutions out-of-the-box. An employee with a connection to agricultural machinery came up with the idea of using repurposed potato belt wagons to transport the peat pellets from the warehouse to the silo. The wagons are loaded with a wheel loader in the warehouse, just as the hopper for the standard pneumatic process is being loaded. From there, the wagons are driven to the reactor silo where they reverse to a hopper with a filter and rotary valve. The conveyor belts move the material into the hopper and from there the pellets are pneumatically conveyed up into the silo. The required conveying and process air is produced with the system’s own compressors that are installed in an adjacent heated 20-ft standard container. Thus, the machine runs self-sufficiently and is independent of maintenance work on the existing conveying stream.



Two major challenges had to be overcome by WWTec to make this project work. Since the dust from peat pellets is explosive, the whole process had to be adapted and tested according to the ATEX directive for explosion protection. WWTec has an excellent partner in Bureau Veritas, who provides global support from development to acceptance and certification on site. Secondly, the project’s location is one of the coldest regions in Europe. Temperatures can drop to -40°C, and machines need to run throughout the year. Wherever possible, components for the equipment where selected to meet the required temperature limits. When no component within the limits was available and lead times for feasible solutions were too long, WWTec installed ATEX-approved heating to make the system winter-proof.

Cooperation between customer and WWTec was spot-on and drawings were exchanged to accommodate the equipment at the best spot on site. A bunker was dug for the hopper to be installed below ground level, so that the conveyor belts from the wagons feed directly into the openings of the hopper. Communication and signal exchange between the conveying unit and the plant was realized on site between WWTec’s and the customer’s personnel. With the described equipment from the second-hand market and from the existing WWTec rental equipment stock, this machine could be completed in record time during an economically difficult phase.

The customer is pleased with a flexible, mobile, and, above all, safe solution for handling peat pellets.

For more information on WWTec GmbH & Co. KG, call +49 (0) 2624 94 370 44 or visit

About the Author(s)

Powder Bulk Solids Staff

Established in 1983, Powder & Bulk Solids (PBS) serves industries that process, handle, and package dry particulate matter, including the food, chemical, and pharmaceutical markets.

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