Flash pyrolysis of biomass and co-pyrolysis with biopolymers

The Kyoto Protocol, which is closely related to the climate change threat, together with the depletion of fossil fuels and materials in general urgently force society to become "renewable". Extensive research and projects dedicated to renewable energy sources such as water, wind, solar and biomass are therefore being earned out worldwide. A final solution satisfying the global demand for energy and raw materials has yet to emerge, however. A diversified portfolio of renewables offers increased potential nonetheless. One such technology able to satisfy a part of the demand for renewable energy and raw materials is the flash pyrolysis of biomass. Flash pyrolysis is defined as heating a material, biomass/waste in most cases, in the absence of oxygen, rather oxygen deficient, in order to produce a liquid, called bio-oil. Besides bio-oil, char (solid residue) and gases are produced as well. The most important features of flash pyrolysis are intermediate high temperatures, high heating rates and rapid cooling of the pyrolytic volatiles. Many commercial reactor configurations, especially designed for flash pyrolysis are available. For this research, the production of valuable bio-oil is put forward. Therefore, constructing a reactor that satisfies all the requirements of flash pyrolysis is defined as the preliminary goal. Flash pyrolysis breaks biomass, which mainly consists of three basic constituents (cellulose, hemicelluloses and lignin) containing high amounts of oxygen, into smaller molecules with water as an unavoidable reaction product. Generally, water is defined as detrimental for the applicability of biooil. The maximum water content of bio-oil is determined to be around 28%, while often higher water contents are reported. The bio-oil, stemming from willow, obtained in this research also shows a higher water content. Therefore, it is intended in this research to reduce the water content or the amount of pyrolytic water by countering its production or by consuming it during pyrolysis. The flash co-pyrolysis of biomass and biopolymers is proposed as an attractive solution. During this process, the biopolymer's ester bonds are supposed to react with the available water resulting in the production of acids and alcohols. For this research, willow has been chosen as the reference biomass material, while polylactic acid (PLA}, com starch, polyhydroxybutyrate (PHB), Biopearls, Eastar, Solanyl and potato starch are selected as the biopolymers under investigation.

Jaar van publicatie:2009

Toegankelijkheid:Open