|Abstract in English:|
Fiber sorghum [( L. (Moench.)] is recognized as having potential as an energy crop to allocate towards biogas or bioethanol production. However, due to the considerable amount of biomass produced, the harvesting presents some drawbacks. In Italy the cultivation of fiber sorghum is concentrated in the North where the harvesting occurs at the end of summer, on plants having, on average, 70% of moisture. For allowing the storage in bales, a product with at least 30% of moisture is required. Drying time of non-conditioned plants in open field may be too long, exposing the mowed biomass to adverse climatic conditions that may negatively affect the drying time and the success of the subsequent baling.
The work presents the first results of a new mower-conditioner designed by CREA-ING (Rome-ITALY) able to guarantee high efficiency in stem conditioning. The experimental tests were conducted in northern Italy where the performance of the machine was analyzed. Importantly, the mechanical action of conditioning apparatus determined a deeper cracking along the stem. As a result, the time required to reach the minimum moisture threshold (30%) for baling was reduced to 72 h hafter mowing. After just 5 days from conditioning, the moisture content was around 20%. To our knowledge, compared with the data of the available literature, this is the best result on drying time. Moreover, the regression analysis showed that for this specific study, none of the tested climatic parameters resulted in a decrease of moisture content in the sorghum biomass, thus confirming that the drying is mainly due to the conditioning action.