Moisture of Bulk Solids
Moisture content measurement ✓ Testing methods ✓ Flow properties impact ✓ Storage considerations ✓ Powder & granulate handling
Mechanisms
Moisture affects flow behaviour via several mechanisms: capillary forces (liquid bridges), van‑der‑Waals forces, electrostatic effects and changes in surface tension. These effects modify interparticle cohesion and can either improve or impede flow. The magnitude of the effect depends strongly on particle size, shape, surface texture and the moisture distribution within the sample.
Recommended measurements
For a practice‑relevant assessment we recommend:
- Yield locus measurements at multiple consolidation stresses to determine the flow limit depending on moisture content.
- Wall friction tests with relevant wall materials and moisture states.
- Moisture content determination using calibrated methods (drying oven, halogen moisture analyzer or equivalent).
Online evaluation — example
Comparison of the yield locus for a sample at different moisture contents (each measured at three consolidation stresses).
Practical recommendations
- Monitor moisture fluctuations in-process and identify critical areas.
- If cohesion increases, consider drying, dosage changes, material treatment or vibration assistance.
- Perform regular measurements (yield locus, wall friction, moisture) for quality assurance.
Professional moisture & flowability analyses
Our laboratory performs standard‑compliant moisture, yield locus and wall friction tests and provides practical, application‑oriented recommendations.
- ✓ Standard‑compliant test procedures
- ✓ Meaningful evaluation reports
- ✓ Tailored recommendations