Recent development of hydrothermal liquefaction for algal biorefinery

Conventional HTL is unsuitable for high value product recovery but this could be overcome using a two-stage sequential hydrothermal liquefaction (SEQHTL) process which operates at reduced temperature and pressure to aid recovery of thermolabile products prior to generating bio-oil.

“The conventional HTL is unsuitable for high value product recovery but this could be overcome using a two-stage sequential hydrothermal liquefaction (SEQHTL) process which operates at reduced temperature and pressure to aid recovery of thermolabile products prior to generating bio-oil [108].”

Different approaches are discussed in recent scientific literature to improve economic issues, such as using co-HTL to cover algal reduced productivity in colder seasons or algal cultivation costs and previously extracting valuable compounds from algae then converting residual biomass into biofuel.

“Different approaches are also discussed in the recent scientific literature and aim to improve the economic issues, such as using the co-HTL process to cover algal reduced productivity in colder seasons [87, 88] or algal cultivation costs [89] and previously extracting valuable compounds from the algae and then converting the residual biomass into biofuel [90–92].”

Other studies focus on TEA and LCA for different scenarios to conciliate biorefinery approaches and improve the viability of algae to biofuel production in environmental, economic, and technological aspects.

“Other studies also focus on TEA and LCA for different scenarios to conciliate biorefinery approaches and to improve the viability of algae to biofuel production in terms of environment, economics, and technology aspects [91, 106, 108, 111].”