Sammendrag
This article deals with the techno‐economic analysis of
biomass to liquid fuel (BTL) production under Norwegian
conditions. The study goal is to produce transportation fuel via
Fischer‐Tropsch synthesis with combined heat production and
electricity as a co‐product. The biorefinery is fed by 150 MW
(HHV basis) of biomass as woodchips or torrefied woodchips.
The biorefinery design is based on high temperature entrained
flow gasification followed by catalytic Fischer‐Tropsch
synthesis. Process modelling software (Aspen Plus) is utilized
to determine the mass and energy streams. Product yield,
energy efficiency and annual wood savings are evaluated
through process simulation and modelling. Economic analysis
is performed by a custom built spreadsheet model to estimate
the capital investment and operating costs. A 20 year discount
cash flow analysis is developed to estimate the cost of
production of fuel. All costs are adjusted to 2012. The total
permanent investment cost requirement for the wet and dry
torrefaction is $888.48 million whereas for the raw case
$906.8 million. The breakeven price of the BTL process yields a
positive net financial value (NPV) above 61 US $/GJ, 51 US $/GJ
and 48 US $/GJ for the selected configurations of raw, dry and
wet torrefaction, respectively. The decrease in fuel production
cost using wet and dry torrefied materials are due to the FT
product yield improvement and improved overall efficiency of
the process.
Keywords: Wet torrefaction, Dry torrefaction,
Gasification, Fischer‐Tropsch, Techno‐economics
biomass to liquid fuel (BTL) production under Norwegian
conditions. The study goal is to produce transportation fuel via
Fischer‐Tropsch synthesis with combined heat production and
electricity as a co‐product. The biorefinery is fed by 150 MW
(HHV basis) of biomass as woodchips or torrefied woodchips.
The biorefinery design is based on high temperature entrained
flow gasification followed by catalytic Fischer‐Tropsch
synthesis. Process modelling software (Aspen Plus) is utilized
to determine the mass and energy streams. Product yield,
energy efficiency and annual wood savings are evaluated
through process simulation and modelling. Economic analysis
is performed by a custom built spreadsheet model to estimate
the capital investment and operating costs. A 20 year discount
cash flow analysis is developed to estimate the cost of
production of fuel. All costs are adjusted to 2012. The total
permanent investment cost requirement for the wet and dry
torrefaction is $888.48 million whereas for the raw case
$906.8 million. The breakeven price of the BTL process yields a
positive net financial value (NPV) above 61 US $/GJ, 51 US $/GJ
and 48 US $/GJ for the selected configurations of raw, dry and
wet torrefaction, respectively. The decrease in fuel production
cost using wet and dry torrefied materials are due to the FT
product yield improvement and improved overall efficiency of
the process.
Keywords: Wet torrefaction, Dry torrefaction,
Gasification, Fischer‐Tropsch, Techno‐economics