Hydrous pyrolysis of digestate as alternative to post composting in a biowaste anaerobic digestion facility

摘要

1.The substitution of composting stage with hydrous pyrolysis process allows a series of advantages. 2.The calculations indicate that HTC allows a higher energy recovery with a limited environmental burden. In fact, the amount of gas emission is negligible if compared with the real produced by the post-composting stage. 3.The liquid effluent production is quite similarfor both the cases while the fresh water consumption can be minimized if the recovery and recycling of water inside the process is carried out, in accordance with the best available technologies criteria. 4.Apart of the discussed items, it should be also taken into account that the reaction time for HTC is much less than needed for composting (3-6 hours against 90 days) and that the operations are carried out in closed vessels with a total containment of odors losses and fugitive emissions. 5.Moreover, the space needed also decreases as a consequence of the high reaction rate.