Fast pyrolysis of macroalga Saccharina japonica in a bubbling fluidized-bed reactor for bio-oil production

Fast pyrolysis of Saccharina japonica alga in a fixed-bed reactor for bio-oil production

“…This difference in the bio-oil yields might be attributed to the different reactor setups and the different reaction conditions. As reported in our previous work [6], the liquid yield obtained from the fast pyrolysis of S. japonica in a fluidized-bed reactor decreased rapidly from 44.99 to 26.67 wt% as the temperature increased from 350 to 500°C; this was caused by the agglomeration between tar, char and fluidizing bed material at high temperatures due to high amount of inorganics and alginate in macro-algal biomasses, hindering the bubbling fluidization and heat transfer between the fluidized-bed material and biomass particles. Fast pyrolysis of S. japonica in the fixed-bed reactor seems unaffected by the agglomeration of tar and char at hightemperature pyrolysis because the feed material was fixed in reaction bed during process.…”

“…The higher heating value (HHV) of the bio-oil was calculated based on Dulong's equation [6,32] [13,29]. Terrestrial biomasses also show similar HHVs.…”

“…The region that represents protons on the carbon atoms of aromatic groups (including heteroaromatics) appears in between 6.0 and 8.5 ppm. The heteroaromatics in the pyrolysis bio-oils of macro-algae consisted of O-containing organic compounds (such as 2-furanmethanol and 2-furyl methyl ketone, which were derived from the decomposition of carbohydrates) [25] and N-containing organic compounds (such as pyridinone and indole, which were derived from the decomposition of proteins) [3,6,17]. For this chemical shift, the sig- nals were higher at 350°C than those at 450°C.…”

“…In our previous work, we investigated the fast pyrolysis of Saccharina japonica in a bubbling fluidized-bed reactor under various temperatures (between 350 and 500°C). The highest bio-oil yield of 44.99 wt% was obtained at a pyrolysis temperature of 350°C [6]. However, higher pyrolysis temperatures induced aggregation of the tar and char, resulting in an increase in the char yield with a rapid decrease in the bio-oil yield.…”

“…Pyrolysis is widely used for the treatment of waste biomass materials for the production of bio-oil due to its reasonable cost and simple operation [2]. Various types of pyrolysis reactors have been utilized for bio-oil production such as fixed-bed [3][4][5], bubbling fluidized-bed [6][7][8], vacuum [9,10], vortex [11], rotating cone [12], and free-fall [13][14][15] reactors. Whilst the pyrolysis of terrestrial biomass has received a great deal of attention using wood [7,16], agricultural crops, and their waste (including rice straw [17], corn stover [18], switchgrass [19], and palm fiber [20]), not as much research has been conducted on the pyrolysis of marine biomass.…”