Production of bio-jet fuel from corncob by hydrothermal decomposition and catalytic hydrogenation: Lab analysis of process and techno-economics of a pilot-scale facility.

Highlights • Process design and techno-economics of pilot bio-jet fuel facility were studied. • Yields of furfural, LA, intermediate, bio-jet fuel were 59.5%, 34.4%, 75% and 51%. • 47.6% energy and 31% carbon of carbohydrate in corncob is recovered in bio-jet fuel. • TCP, OPEX and MSFB (no tax) was $3.96 MM, $1.18/L and $1.45/L for a 1.3 ML/a facility. • Economies of scale on MSFB is obvious when the discount rate increases and taxes impose. Abstract Process design and techno-economic analysis of a pilot bio-jet fuel production facility were investigated using Aspen plus software and net present value method (NPV). This process include two-step hydrothermal decomposition of corncob to furfural (steam stripping of hemicellulose) and Levulinic acid (LA, acidic hydrolysis of cellulose), oxygenated precursor production via aldol condensation reaction of furfural and LA, and the subsequent hydro-processing for oxygen removal. Lab experiments on the major area of the process were carried out. The yields of furfural, LA, oxygenated precursor and bio-jet fuel-range hydrocarbons (C 8 –C 15 ) were 59.5% (based on hemicellulose), 34.4% (based on cellulose), 75% (based on furfural and LA input) and 51 wt% (based on precursor) respectively. These values were used as the input information for the process simulation of a first-of-a-kind pilot facility for 1.3 ML/a bio-jet fuel production using this pioneering technology. The mass and energy analysis from Aspen plus model shows that the bio-jet fuel yield was 0.125 tonne/tonne dried corncob. 31.0% of carbon atoms and 47.6% of potential energy from carbohydrate compounds of corncob leave as bio-jet fuel. The estimated consumption of water, steam and electricity is relatively high of 12.3 kg, 63.7 kg and 1.22 KW h respectively due to small simulation scale and lack of process optimization. The total capital cost was ca. $3.96 MM for the 1.3 ML/a facility, of which 28% of equipment investment is spent for oxygenated precursor production. The total operation expense (OPEX) is $1.18/L bio-jet fuel, including variable and fixed costs. Expenses on corncob, catalytic catalyst and H 2 contribute 23%, 19% and 16% respectively. Single point sensitivity analysis of the major breakdown of OPEX shows that catalyst lifetime is the priority factor. Economy of scale of minimum selling price of bio-jet fuel (MSPB) for different capacity facilities (1.3 ML/a, 6.5 ML/a and 13 ML/a) was investigated using different discount and tax rates, of which the lowest MSPB was $0.74/L with a subsidy of $0.31/L at 10% discount rate. [ABSTRACT FROM AUTHOR]