Selection of Temperature for Bio-oil Production from Pyrolysis of Algae from Lake Blooms

A large abundance of biomass waste is generated from harmful algal blooms (HABs) which dramatically damages the environment. Algae from lake blooms was pyrolyzed in a fixed-bed reactor at 300-700 degrees C in order to evaluate the effect of temperature on the product distribution and bio-oil quality. Yields and compositions of bio-oil, char, and gases were analyzed. The results demonstrated that the maximum yield (59%) of algal bio-oil was obtained at 500 degrees C. The bio-oil from algal blooms was characterized with higher heating value (about 21 MJ/kg) and nitrogen content (2.68%) when compared with pine sawdust. Elevated temperatures improved the bio-oil quality by increasing its heating value and hydrocarbon content. However, excessively higher temperatures also lead to the formation of undesired products such as nitrogenous compounds and polycyclic aromatic hydrocarbons (PAHs).