Temperature influence on the fast pyrolysis of manure samples: char, bio-oil and gases production

Abstract

Abstract. Fast pyrolysis characterization of three dry manure samples was studied using a pyrolyzer. A heating rate of 600°C/s and a holding time of 10 s were selected to reproduce industrial conditions. The effect of the peak pyrolysis temperature (600, 800 and 1000°C) on the pyrolysis product yield and composition was evaluated. Char and bio-oil were gravimetrically quantified. Scanning electron microscopy (SEM) was used to analyse the char structure. H2, CH4, CO and CO2 were measured by means of gas chromatography (GC). A decrease in the char yield and an increase of the gas yield were observed when temperature increased. From 800°C on, it was observed that the char yield of samples Dig R and SW were constant, which indicated that the primary devolatilization reactions stopped. This fact was also corroborated by GC analysis. The bio-oil yield slightly increased with temperature, showing a maximum of 20.7 and 27.8 wt.% for samples Pre and SW, respectively, whereas sample Dig R showed a maximum yield of 16.5 wt.% at 800°C. CO2 and CO were the main released gases whereas H2 and CH4 production increased with temperature. Finally, an increase of char porosity was observed with temperature.

Biomass Fast Pyrolysis Using a Novel Microparticle Microreactor Approach: Effect of Particles Size, Biomass Type, and Temperature

“…Figure thus represents the effect of temperature on the amount of pyrolysates produced for the different biomass types. Although a straight line through the data provides a good fit ( R 2 = 0.97), the collective data suggests an inflection between 500 and 900 °C that might relate to char decomposition , and the secondary tar reactions. , Furthermore, these results are in good qualitative agreement with the yield of gas at different reactor temperatures for other biomass types reported in vastly different studies. − The MSMR experiments are inherently dynamic; i.e., events are always non-isothermal. For constant reactor temperature, small particles heat faster.…”