Techno-economic analysis of liquid fuel production from woody biomass via hydrothermal liquefaction (HTL) and upgrading

• Bench-scale hydrothermal liquefaction (HTL) and hydrotreating tests were conducted.
• A techno-economic analysis was conducted for the HTL and upgrading systems.
• A state-of-technology case was evaluated based on the best available test data.
• A goal case was evaluated considering potential process improvements.
• Sensitivity analyses were conducted for alternative configuration and selected parameters.

Techno-economic analysis (TEA) was implemented to evaluate the feasibility of developing a commercial large-scale woody biomass HTL and upgrading plant. In this system, woody biomass at 2000 dry metric ton/day was assumed to be converted to bio-oil via HTL and further upgraded to produce liquid fuel. Two cases were evaluated: a state-of-technology (SOT) case with HTL experimental testing results underpinning the major design basis and a goal case considering future improvements for a commercial plant with mature technologies. Process simulation and cost analysis were conducted. The annual production rate for the final hydrocarbon product was estimated to be 42.9 and 69.9 million gallon gasoline-equivalent (GGE) for the SOT and goal cases, respectively. The minimum fuel selling price (MFSP) was estimated to be $4.44/GGE for the SOT case and $2.52/GGE for the goal case. For advancing from the SOT to the goal case, the assumption of reducing the organics loss to the water phase led to the largest reduction in the production cost. Alternative configuration of small scale distributed HTL plants was evaluated. Sensitivity analysis identified key factors affecting the goal case and its cost uncertainties resulting from the assumed uncertainties in selected parameters.