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Title: Hydrothermal Processing of Macroalgal Feedstocks in Continuous-Flow Reactors

Journal Article · · ACS Sustainable Chemistry & Engineering
DOI:https://doi.org/10.1021/sc400251p· OSTI ID:1129301

Wet macroalgal slurries have been converted into a biocrude by hydrothermal liquefaction (HTL) in a bench-scale continuous-flow reactor system. Carbon conversion to a gravity-separable oil product of 58.8% was accomplished at relatively low temperature (350 °C) in a pressurized (subcritical liquid water) environment (20 MPa) when using feedstock slurries with a 21.7% concentration of dry solids. As opposed to earlier work in batch reactors reported by others, direct oil recovery was achieved without the use of a solvent, and biomass trace mineral components were removed by processing steps so that they did not cause processing difficulties. In addition, catalytic hydrothermal gasification (CHG) was effectively applied for HTL byproduct water cleanup and fuel gas production from water-soluble organics. Conversion of 99.2% of the carbon left in the aqueous phase was demonstrated. Finally, as a result, high conversion of macroalgae to liquid and gas fuel products was found with low levels of residual organic contamination in byproduct water. Both process steps were accomplished in continuous-flow reactor systems such that design data for process scale-up was generated.

Research Organization:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC05-76RL01830
OSTI ID:
1129301
Report Number(s):
PNNL-SA-97137; EB5706000
Journal Information:
ACS Sustainable Chemistry & Engineering, Vol. 2, Issue 2; ISSN 2168-0485
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English