Title:
Combustion of Vapours from Pyrolysis of Residual Forest Biomass in a Pilot-scale Auger Reactor: Process Analysis and Gaseous Emissions
Author(s):
Tarelho, L.A.C., Santos, M.C., Marques, C.C., Silva, F.G.C.S., Matos, M.A.A.
Document(s):
Paper
Abstract:
It was successfully demonstrated the autothermal operation of an integrated prototype of pyrolysis system for production of biochar. The prototype is composed of a pyrolysis Auger reactor integrated with a combustion reactor for pyrolysis vapors. The integrated prototype was designed to a biomass processing capacity of up to 10 kg/h, and was tested with a biomass feed rate from 3.0 to 4.7 kg/h, using residual forest biomass (RFB) from acacia, gorse, broom and giant reed. The solids residence time in the pyrolysis Auger reactor was between 17 and 18 minutes. For the conditions tested, the biochar yield was in range 0.19 to 0.27.kg/kg biomass (dry basis). The combustion of pyrolysis vapors was characterized as very stable, and with temperatures up to 1100.ºC at the location of the pyrolysis vapors combustion flame, and decreasing along the combustion chamber towards the exit. Temperatures along the length of the combustion chamber were in range from 1100ºC to 300ºC, and were influenced by the excess air and biomass type used. An efficient combustion of pyrolysis vapors was observed, as reflected by relatively low concentrations of CO in the combustion gas at the exhaust, with average values below 90 mg/Nm3 (6% O2, dry gas). Relatively high concentrations of NO (expressed as NO2, up to 1196 mg NO2/Nm3, 6% O2, dry gas) and HCl (up to 483 mg HCl/Nm3, 6% O2, dry gas) were observed in the combustion flue gas for some biomass types.
Keywords:
biomass, combustion, emissions, pyrolysis
Topic:
Biomass Conversion to Intermediate Bioenergy Carriers and Sustainable Biofuels
Subtopic:
Pyrolysis
Event:
32nd European Biomass Conference and Exhibition
Session:
5CO.7.2
Pages:
656 - 665
ISBN:
978-88-89407-24-0
Paper DOI:
10.5071/32ndEUBCE2024-5CO.7.2
Price:
FREE
