Canadian Bio-Oil from Pyrolysis, Since 1989

Pyrolysis can take biomass and turn it into liquid pyrolysis oil -- bio-oil -- , gas, and biochar. It happens at high temperature in the absence of oxygen. Pyrolysis has been around for a while, but as the cost of procuring petro-oil grows greater, pyrolysis and other bioenergy approaches will become more important. The advantage of pyrolysis over gasification, is that pyrolysis oil can be stored, piped, shipped, and otherwise used at leisure. Gasification products must be used promptly to prevent degradation.

During the production of bio-oil, solid biomass wood is blasted into a tornado of hot sand at the bottom of a conversion unit. In less than two seconds the wood is vaporized. It is then condensed and recovered as a liquid bio-oil.

Seventy-five percent of the solid wood biomass injected into the RTP system is transformed into high yields of espresso-like bio-oil. The liquid wood is not a tar. It is a pourable fluid, which Ensyn treats as its own version of crude oil, and is used as a resource to make other products, such as high value biochemicals, in the same way petroleum crude is used in a variety of applications.

The remaining 25 percent of the biomass is converted into non-condensable gas and charcoal. These byproducts are fed back into a reheater in order to keep the tornado of sand at the required processing temperature. More energy is in the gas and char than required to drive this process, so the reheater has a surplus of energy. Ensyn uses this surplus to dry the wet biomass that arrives at the facility and to supply other industrial heat requirements.

Since 1989, Ensyn’s RTP plants have been making liquid bio-oil from solid wood biomass through a patented fast pyrolysis thermal process. Liquid bio-oil can replace heating fuel, natural gas and coal in a vast array of boiler applications. The company produces renewable energy in the form of a liquid fuel as opposed to a gas or solid fuel, which enables what is known as “decoupling.” With decoupling, production can be separated by time and space from the actual use of the product. _Bioenergy

Pyrolysis will be an important method in the bioenergy industry. Providing sufficient feedstock for bioenergy production will be a challenge that will have to be faced over the next decade or two.

Speaking of bioenergy, the Johnny Walker distillery in Scotland is raising $100 million to add a biomass CHP plant to provide most of its own electricity and steam from the distillery's effluent. The project illustrates a growing trend toward producing useful energy from what was formerly considered bothersome garbage.