Pyrolysis of Broiler Manure: Char and Product Gas Characterization

Value-added materials produced from broiler manure can be a renewable alternative to its problematic disposal. Pyrolysis of broiler manure (litter and cake) produces char, bio-oil, and biogas. In this study broiler manure chars were characterized for their ability to adsorb selected metal ions. Char yields for pelletized broiler manure slowly pyrolyzed at 700 and 800 °C for 1 h ranged between 29.6% and 33.5%. Surface areas for the broiler litter and cake decreased with pyrolysis temperature with 238 and 318 m2/g and 199 and 261 m2/g for 700 and 800 °C, respectively. Broiler manure chars removed significantly more metal ions from solution (up to 0.91 mmol/g Cu2+ and 0.96 mmol/g Zn2+) when compared to chars produced from coal, wood, or coconut shells (up to 0.0 mmol/g Cu2+ and 0.10 mmol/g Zn2+). Composition of the biogas generated during fast pyrolysis between 700-900 °C, as a measurement of its energy potential, was also determined. The major components of the noncondensable gas produced during fast pyrolysis of broiler manure, included CO, CO2, low molecular weight hydrocarbon gases, and H2. Except for CO, noncondensable gases increased with pyrolysis temperature.