Page 135 - Advances in bioenergy (2016)

hydrocarbon product was found to remain nearly identical.

2
A new IH pilot unit, capable of continuously converting approximately 50 kg/day of feedstock,
was designed and constructed. Beginning in 2012, Marker and others presented initial results
of continuous, long-term testing, carried out in the 50 kg/day, continuously operated pilot
plant. 27-31 Long-term performance of catalysts was examined, and the stability of the process
was demonstrated over significant periods of time on stream. Earlier work had been carried
out in the context of experiments lasting no more than a few hours, where at most a few

kilograms of biomass were converted. As shown in Figure 5.2, continuous testing of the 50
kg/day pilot unit has demonstrated consistent yields of liquid hydrocarbons over almost 700 of
hours of operation.

2
Table 5.1 Liquid Yields and Feedstock Flexibility Associated with the IH Process 23

Wood Lemna (Minor Aquaflow Bagasse Blue Marble Corn
Duckweed) Micro-Algae Macro-Algae Stover
Feed %C 49.7 46.3 43.1 43.1 34.0 40.2

Feed %H 5.8 5.8 6.1 5.0 4.43 5.0

Feed %O 43.9 35.7 20.4 35.3 23.6 35.7
Feed %N 0.11 3.7 6.5 0.34 4.6 1.0

Feed %S 0.03 0.3 0.7 0.10 1.9 0.05

Feed %Ash 0.5 8.2 23.1 16.2 29.4 18.1

Feed %H/C 1.40 1.50 1.70 1.39 1.56 1.49
Typical %C + Liquid 25– 30 46 30 35 21
4
Yield (MAF) 28
C + gallon/ton MAF 82 100 157 100 119 67
4

%Oxygen <1% <1% <1% <1% <1% <1%
TAN # <1 <1 <1 <1 <1 <1

Reproduced with permission from Terry Marker.

As long as feedstock composition (in this case, maple and pine), operating conditions, and
catalyst composition were held constant, the liquid hydrocarbon product composition remained
consistent. Considerable technical challenges were addressed; many of these were associated
with the introduction of solid feedstocks into pressurized process vessels along with the
recovery of a solid char product. It was shown that the pilot plant consistently operated in a
way that would allow the required hydrogen for hydrotreating to be produced via reforming of
the light, noncondensable hydrocarbon vapors. While a reformer was not integrated into the 50

kg/day pilot plant, the composition of the process vapor was documented, and found to be
compatible with commercially available reformers.

31
2
A detailed technoeconomic analysis of the IH process was developed by Roberts et al. This