NEWS - Biomass

Moisture measurement of biomass: methods at a glance

As a renewable, environmentally friendly energy source, biomass has become an indispensable part of modern energy production. The exact determination of the water content is crucial for the quality, calorific value and storability of the raw material. Emissions, ash content and bulk density also depend significantly on the moisture content.

But how can the moisture content of biomass be measured precisely and efficiently? Schaller Messtechnik 's EN ISO/IEC 17025 accredited test laboratory provides a practical overview of common measurement methods.

1. Laboratory method - The reference for moisture measurement

The classic drying oven method according to DIN EN ISO 18134-2 is considered the gold standard: the biomass is dried for at least 12 hours at a defined temperature until a constant mass is achieved. The water content is precisely calculated from the mass loss.

Advantages:

• High measurement accuracy
• Standard-compliant and comparable
• Reference for other procedures

Disadvantages:

• Time consuming
• Complex handling
• Risk of defects due to evaporation of other ingredients (e.g. resins)

2. Electronic rapid measurement methods - fast, mobile & practical

Electrical measuring methods have proven their worth for rapid on-site use. They allow the water content to be determined quickly without time-consuming sample preparation.

1. a) Conductance-based methods

This method utilizes the increasing electrical conductivity of biomass with increasing water content. The probe is inserted directly into the material - the measurement takes place in real time.

Advantages:

• Very fast results
• No sample loss
• Easy to use

Disadvantages:

• Strong temperature dependence
• Requires exact temperature compensation

1. b) Dielectric processes

Here, the measurement is based on the dielectric constant of water. High-frequency measurement signals are used to determine the moisture over large quantities of biomass.

Advantages:

• Lower temperature dependency
• Suitable for large sample quantities
• Non-invasive

Conclusion: The right method for the right purpose

All measuring methods have their strengths and weaknesses. The choice of the right method depends on the intended use: while maximum precision is required in the laboratory, high-speed measuring devices score points in mobile use thanks to their speed and ease of use.

Recommendation:
Regardless of the method, compliance with applicable standards should always be ensured. This is the only way to ensure standardized, reproducible and comparable moisture measurement. The laboratory method remains the indispensable reference - but modern measuring devices offer an ideal supplement for everyday practice.