Canadian Company Dynamotive Takes Pyrolysis to Australia

Dynamotive Energy Systems is taking its method of fast pyrolysis and bio-oil upgrading to Australia, where it will be used to turn plantations of mallee (a type of eucalyptus) into bio-fuels, some suitable for use in aviation.

Pyrolysis oils present several challenges to overcome as they are typically high in water, solids and acids and do not meet the specifications of fossil fuels. Dynamotive R&D developed a process to upgrade pyrolysis oil that can potentially overcome these challenges and could provide an economically viable path to upgrade bio-oils to mobile fuels. _GCC

Dynamotive's process is continually being refined, and consists of a two-step basic approach:

Stage 1 (Hydroforming)
The first stage is hydro-reforming of biooil:
Stabilize it;
Render it miscible with hydrocarbon liquid;
Cause phase separation of the water in the BioOil;
Lower its viscosity;
Lower its corrosivity and;
Lower its oxygen content from ~50% in the raw biooil to around 10%.

Once BioOil is put through the Hydroforming process it becomes a product designated UBA. However, UBA still contains ~ 10% oxygen. It is not a pure hydrocarbon and needs further treatment to convert it to motor fuel grade products. The hydro-reforming reaction was carried out in an autoclave.

Stage 2 (Hydrotreating)
The second stage involves a conventional hydrotreatment over a commercial catalyst. Commercial hydrotreating catalysts are available that can steer the product towards diesel/gasoline/jet fuel etc. at somewhat higher severity conditions. _Dynamotive

Clearly everything revolves around the economics of the process. Stage 1 treatment can turn pyrolytic bio-oil into a partial substitute for fuel oil in stationary machinery. In order to turn the bio-oil into transportation fuels for land, sea, or air vehicles, hydrotreatment (stage 2) is required -- which adds another level of expense.

Clever chemical and industrial engineers are learning better ways to get the hydrogen used for hydrotreating from biomass waste itself, just as the non-condensing gases from the pyrolysis process are used for process heat to save fuel costs.

Pyrolysis can feed into multiple product lines, or it can be used as a pre-processing stage to facilitate inexpensive transport to a gasification and catalytic synthesis facility. Going the latter route adds further layers of expense to the process, but much higher value products can be created using more sophisticated synthetic processes.

It is the versatility of pyrolysis which is likely to place it close to the center of a building biomass to fuels infrastructure.