Quality of biochar and fuels obtained in the process of slow pyrolysis of chicken manure

Abstract

© 2019 ETA-Florence Renewable Energies. In recent years, pyrolysis of different kinds of biomass is the object of intensive research. The products of this recycling method are pyrolysis fuels as well as biochar. Significant properties and the quality of pyrolysis products depend on pyrolysis conditions (the peak pyrolysis temperature, the duration of the pyrolysis) as well as on the type of material pyrolyzed. The aim of this study was to estimate the quality of biochar and of the two fuels (semi-liquid tar and liquid condensate) that were obtained in the process of slow pyrolysis of chicken manure by 400 ⁰C peak temperature that lasted for 6 durations (from 20 to 120 min). Total C and N content did not differ significantly in the biochar samples and ranged between 48.52 and 53.40%, correspondingly. Biochars obtained during 40-100 min were less toxic than the others. Calorific values of tars ranged between 26.4 and 31.7 MJ kg-1, while the highest value was revealed for 80-min sample with the lowest asphaltenes content (~25%). Calorific values of liquid condensates ranged between 1.5 and 4 MJ kg-1, while the highest value was revealed for 80-min sample most likely due to the lowest water content (89%).