Title:
New Concept for Two-Stage Combustion in a Wood Stove with Combustion Retort
Author(s):
Nussbaumer, T., Odermatt, P.
Document(s):
Paper
Abstract:
The project presents an innovative combustion concept for log wood in a wood stove consisting of a retort for the gasification and a subsequent combustion chamber for the gas phase oxidation. The wood logs are gli-ding from the fuel hopper into the retort by gravity enabling combustion at a low heat output rate of 7.4 kW during a long combustion period of 4 hours at high combustion quality. CO emissions of less than 500 mg/m3 and particle emissions of 15 mg/m3 at 13 Vol.-% O2 are achieved including the start-up phase from the fuel ignition. The principle can be applied for natural draught and enables an operation without intervention from the fuel ignition to the end. CFD was applied to optimise the air injection and the combustion design. The results show that beside high turbu-lence, a high impulse ratio between secondary air and the main gas flow is favourable. Since both induce an increased pressure drop, respective measures are limited for natural draught however. Hence a homogeneous distribution of the secondary air into the main stream is advantageous. Tests to validate the combustion concept were performed by measuring O2, CO2, CO, VOC, CH4, NMVOC, particulate matter and efficiencies.
Keywords:
emissions, modelling, modeling, wood stove, two-stage combustion, low heat input
Topic:
R&D on Biomass Conversion Technologies for Heating, Electricity and Chemicals
Subtopic:
Solid biofuel combustion for small and medium scale applications
Event:
21st European Biomass Conference and Exhibition
Session:
2CO.4.3
Pages:
555 - 561
ISBN:
978-88-89407-53-0
Paper DOI:
10.5071/21stEUBCE2013-2CO.4.3
Price:
FREE
