Treatment of granulated organic manure based on bird droppings by hydrothermal carbonization and torrefaction methods

Abstract Hydrothermal carbonization (HTC) and torrefaction are modern low-temperature methods of converting different types of biomass into biocoil. In both processes temperature significantly affects the product distribution and character of solid product. The heating values of HTC biocoil was much higher than torrefacted biochar and 40% higher compared to the initial raw materials (15.68 MJ/kg for raw materials, 22.3 MJ/kg for HTC 210 °C). Biomass has increased carbon content. The maximun one has biochar obtained at 210 °C (55% higher compared to the initial raw materials). The energy densification ratio and energy yield was also higher in HTC process compared to torrefaction process. Hydrochar has less ash that biochar obtained by torrefaction due to washing part of inorganic into the liquid phase.