*2.4. Ultimate Analysis*

Proximate and ultimate analysis provided information on the major categories that are important for the thermal conversion of biomass such as moisture, Volatile Matter (VM), ash, carbon etc. The moisture content of the samples was measured by drying according to the procedure UNE-EN ISO 18134-1: 2015; the nitrogen, carbon and hydrogen percentages were determined according to the UNE-EN ISO 16948: 2015 standard, the VM by the UNE-EN ISO 18123: 2015, the sulfur by UNE-EN ISO 16994: 2015, and the oxygen by di fference. The measurement was conducted by the Centre for Research & Technology Hellas/Chemical Process and Energy Resources Institute (CERTH/CPERI), Athens branch. The proximate and ultimate analysis data for untreated and torrefied barley straw are presented in Table 2. The torrefaction conditions were for the optimal heating value.


**Table 2.** Composition of untreated and torrefied barley straw.
