Catalytic pyrolysis of biomass for improved liquid fuel quality

Project Information

Grant agreement ID: JOR3950081

Start date 1 January 1996

End date 30 June 1998

Funded under

• Specific programme for research and technological development, including demonstration in the field of non-nuclear energy, 1994-1998

Total cost € 0,00

EU contribution No data

Coordinated by

FEDERAL RESEARCH CENTRE FOR FORESTRY AND FOREST PRODUCTS
Germany

Deliverables

Catalytic Pyrolysis Of Biomass For Improved Liquid Fuel Quality

The main part of the work comprised the use and evaluation of catalysts in fast pyrolysis aimed at improving the quality of the liquids in terms of stability. More than 50 catalysts were tested in screen experiments using micro-scale and bench-scale fast pyrolysis apparatus. Four modes of operation were used: co-feeding the catalyst together with the biomass, replacing the sand fluid bed with a catalytic one (in bed), including catalysts in the primary reactor (ex bed) and close-coupling catalysts in a secondary reactor. Commercial FCC catalyst was also tested in a circulating fluidised bed and a rotating cone reactor showing that the catalyst was too active leading to a reduced oil and increased gas yields. The experiments revealed that thermally expanded slate, a cheap construction material, gave the best quality liquids as measured by initial viscosity, stability and water content. Therefore, larger scale experiments were conducted with this type of material using lab-scale and pilot plant scale fluid bed reactors and a rotating cone reactor. The results show that laboratory results could be transferred. However, difficulties in the fluid bed reactors were observed due to the different fluidisation behaviour of slate. Substantial technical improvements of the pilot plants with fluid bed reactor and rotating cone reactor could be made in the course of the project. Both oxidants and anti-oxidants have been used for liquid modification. The addition of a 10% wt /wt aqueous solution phenol was found to result in the best quality pyrolysis liquid. This chemically modified pyrolysis liquid was more stable and had a lower water content than regular pyrolysis liquid. A process has been tested for the use of biomass pyrolysis liquid product as a partial substitute for formaldehyde-based resins in the production of composite panel. The technology was proven at the lab scale. The pyrolysis oil can be used as such to replace up to 20% of the UF/PF binder in composite board production with no significant impairment of the board strength properties. Conclusions The use of catalysts in fast pyrolysis is a suitable measure to improve the stability of liquids with respect to viscosity and water content. The understanding of the catalyst’s behaviour in fast pyrolysis is not yet understood. Selectivity, reactivity and specificity have still to be investigated. Models for various fast pyrolysis reactor configurations were developed and allow the prediction of the yields of the three main products oil, gas, and char. However, the performance of the models should be further improved. One of the most important result from the project was the addition of crude pyrolysis liquids to adhesives to substitute expensive phenol in resin formulations.