Comparison of different methods for the determination of moisture content in biomass

The purpose of this study was to compare different methods for the determination of moisture in biomass. Twenty different biomass materials from various places in Europe were investigated for total moisture using oven drying in air at three different temperatures (80, 105 and 130 °C), distillation with xylene, and freeze drying. In addition, the materials were used for the comparison of different methods for the determination of moisture in the analysis sample. In all cases CEN TC335 Solid Biofuels—Methods for determination of moisture content—Oven dry method was used as the reference method. Significant differences were obtained between the oven-drying methods in air at various temperatures. Similar results were found for some materials when comparing the reference method with xylene distillation and freeze-drying methods. In some cases the discrepancies were explained by the loss of volatile organic compounds during the oven-drying step at elevated temperatures. Small differences were found in the comparison of methods for the determination of moisture in the analysis sample.