Page 151 - Advances in bioenergy (2016)

The rationale for these analyses is the potential to produce bio-oil in small scale in a
distributed fashion in proximity to the biomass resource, thereby reducing the transportation
costs for raw biomass. The transporting of bio-oil to a central upgrading facility allows the
scale-up efficiencies to be attained. In addition, if the upgrading facility is close to a petroleum
refinery, which would be operating at even a larger scale, there is potential for additional
savings for by-product gas utilization for hydrogen production and other infrastructure

interactions. 26

Direct Fuel Blending Possibilities

Hydrotreated bio-oil products from bench-scale tests were collected and segregated to recover
sufficient material of appropriate quality (less than 0.5% residual oxygen) to distil a jet fuel
range product. This distillate was further treated to reduce the oxygen content from 0.2%
following hydroprocessing to 0.02% before blending. The upgraded fast pyrolysis product was
blended with synthetic paraffinic kerosene from vegetable oil to produce the first entirely
biomass-based turbine fuel. The cyclic and aromatic nature of the pyrolysis product provided
the appropriate jet fuel properties in combination with the straight chain aliphatics from the
lipids, and the fuel blend met the requirements for the engine manufacturer. The demonstration
of the fuel was the operation of an unlimited class hydroplane for a single test of three laps

around a 2.5-mile course. 23
The corrosion issue is also addressed by the deoxygenation of the bio-oil. Corrosion tests of
hydroprocessed bio-oil, as a pure component, confirm that the reduction to <0.5% residual

oxygen reduces the corrosion properties to a very low level. Based on 500 h exposure at 50°C,
the rate on carbon steel as well as the several stainless steels tested was negligible. 27

CONCLUSIONS

The use of fast pyrolysis to produce liquid products from solid biomass has been demonstrated
commercially. Catalytic hydroprocessing can be applied to the bio-oil product from fast
pyrolysis to deoxygenate the bio-oil and produce hydrocarbon products that can serve as
renewable transportation fuels. The process development of the hydroprocessing is just
moving to scale up from the laboratory. Larger quantities of product should be available in the
near future to allow extensive testing and validation of the fuel properties.

NOTES

* Correspondence to: dougc.elliott@pnnl.gov

REFERENCES

1. Bridgwater AV. Review of fast pyrolysis of biomass and product upgrading. Biomass
Bioenergy 2012, 38:68–94.