The 6th International Conference on Biomass Energy (ICBE2018)

381 / 2018-08-01 15:22:15

Continuous anaerobic digestion of aqueous products of hydrothermal liquefication of corn straw

Plenary track > E.Gaseous Biofuel

Hydrothermal liquefaction (HTL) has been well studied for the bio-oil production from lignocellulosic biomass. One critical challenge of HTL is its high concentration of organics, complex components, fermentation inhibitors especially under higher HTL temperature (around 300 oC). Here we report the anaerobic digestion (AD) process performance of HTL aqueous products (HTL-ap) at thermophilic (55 oC) and mesophilic conditions (37 oC) via an up-flow anaerobic sludge bed reactor (UASB). Increased digestion temperature in fact decreased COD removal efficiency on the steady-state with stabilized at 45.0 % COD removal efficiency and methane yield of 84 mL CH4/g COD while the mesophilic reactors stabilized at 61.6% COD removal efficiency and methane yield was 194 mL CH4/g COD. One specific approach, known as LC-OCD-OND were used to characterize the fraction assignation such as humic substances, biopolymers, building blocks, low molecular weight organic acids and neutrals, hydrophobic organic carbon. Bacterial metabolism analysis was also used to understand the production of biogas difference of mesophilic and thermophilic digestion respectively and the presence of different metabolites indicate the different metabolomic pathways of the different groups of bacteria.