PRELIMINARY STUDY ON GASIFICATION BIOCHAR FOR THE REDUCTION OF SWINE SLURRY NITROGEN RELATED GREENHOUSE GASES EMISSIONS

The objective of this study is the evaluation of the best methodology for applying biochar from gasification in the reduction of nitrogen based GHGs emissions, in swine slurry in an open slurry-lagoon. European regulations and fundings are spurring in the direction of reducing equivalent greenhouse gases emissions, especially those derived from nitrogen. Swine farms are among the main culprits of nitrogen-derived greenhouse gas emissions. In the Emilia-Romagna region, in Italy, it is customary to accumulate slurry from large swine farms in open-air tanks, favoring important nitrogen emissions. Biochar, whether from pyrolysis or gasification, has already consistently demonstrated its ability to reduce and retain nitrogen emissions. However, a simple and economical method for applying this material on a large scale has not yet been defined. In this study, with a pilot-scale approach, we want to investigate three methodologies for applying biochar. To do this, 12 reactors of 1 m3 in volume each, were used to study three theses plus the control case, out of three repetitions. The theses considered are biochar used on floating grates (Th1), biochar used inside a contact filter (Th2), biochar used inside a nitrifying-denitrifying filter (Th3). The results confirm the effectiveness of using biochar for reducing greenhouse gas emissions from swine slurry. The combination of a nitrifying-denitrifying process with a substrate such as biochar, has guaranteed the best performance in terms of reducing greenhouse gas emissions. Furthermore, this has made it possible to obtain a final slurry aided with biochar that can be used as a soil amendment.