Design and operation of a conical spouted bed reactor pilot plant (25 kg/h) for biomass fast pyrolysis

• The spouted bed pyrolysis plant performs well in the continuous operation.
• A maximum bio-oil yield of 65.7% has been obtained operating at 480 °C.
• Temperature causes an increase in gas yield and a decrease in bio-oil and char.
• Bio-oil light fraction can be used as fuel.
• Bio-oil heavy organic fraction is suitable for the production of phenolic resins.

An original pyrolysis pilot plant provided with a conical spouted bed reactor has been designed and built for treating 25 kg/h of biomass. The scale-up of the process has been based on the previous knowledge acquired in both hydrodynamics and pyrolysis studies carried out at laboratory scale, as well as on the research conducted on 1:1 scale reactor made of methacrylate and operating at ambient conditions. The main components of the pyrolysis pilot plant are described and their performance is tested and assessed. Furthermore, preliminary results obtained by pyrolysing pinewood sawdust are presented. The pyrolysis plant operates in continuous mode for long periods without major operation problems. The excellent features of the spouted bed reactor (high heat transfer rates, short residence times, continuous char removal, etc.) allow obtaining high bio-oil yields. Thus, the maximum bio-oil yield is obtained at 480 °C, reaching a value of 65.8%, with the yields of gas and char being 18.8% and 15.4%, respectively. The bio-oil obtained has suitable features for its subsequent valorization.