Extrusion International 3-2026

20 Extrusion International 3/2026 INDUSTRY NEWS Measuring Moisture in Bulk Solids With the launch of the DewTector®, Coperion introduc- es an innovative moisture measuring device designed to provide reliable, automated online measurements of sur- face moisture content in bulk materials, particularly plastic pellets. The patent-pending device offers an economical, simple and reliable method to help plastic manufacturers and recyclers monitor moisture levels more ef ciently. It addresses a critical challenge faced by processors in main- taining both product quality and maintaining compliance with industry standards. The DewTector uses a straightforward approach ─ it in - troduces a partial ow of bulk solids into a pressure-tight product chamber. The system determines the moisture content by analyzing the moisture released into the air- ow. As the air absorbs moisture, it is analyzed by a hy - grometer that measures only water content. This target- ed detection ensures reliable results unaffected by other substances or changes in material composition. The sys- tem neither requires extensive calibration, nor the use of chemicals for different materials or recipes, making it easy to operate and maintain. The system achieves an accuracy of +5% to −15% across moisture levels ranging from sev - eral thousand ppm to a few hundred ppm, with up to ten measurements per hour. Challenges of Moisture Measurement in Plastics Plastic manufacturers often face the challenge of mois- ture entering their nal products, which can originate from various sources such as insuf cient drying, defective water separators, leaking wash nozzles, or environmental factors like rain and condensation. If moisture levels go undetect- ed, it can lead to costly product complaints and reputation- al damages. Additionally, processors must adhere to strict moisture content limits to ensure high-quality output, and the recycling sector requires dry input materials for effec- tive processing. Traditionally, moisture measurement has been labor- intensive and prone to inaccuracies, often relying on sporadic manual assessments of relative humidity in bags and containers. Existing automated methods, such as capacitive and microwave resonance techniques are typically complex, expensive, and require extensive cali- bration for different formulations, making them imprac- tical for many users. By simplifying moisture measurement and reducing the labor and time spent on manual sampling and analy- sis, the DewTector enhances operational efficiency while providing accurate, real-time data critical for process control. Coperion GmbH www.coperion.com DewTector in a typical bypass line con guration. Its compact design, with a height of only 184 mm (ange to ange), simpli es process integration (Images: Coperion GmbH, Weingarten, Germany) A cross-sectional view of the DewTector's product chamber, illustrating the air ow. The direct measurement approach using a hygrometer eliminates the need for complex calibrations for each formulation