More than 2000 hours of gas engine operation with producer gas from biomass as fuel has been conducted on the gasification CHP demonstration and research plant, named “Viking” at the Technical University of Denmark. The gas engine is an integrated part of the entire gasification plant. The excess heat from the exhaust gas is utilised for drying and pyrolysis of the biomass in the gasification system, and the engine directly controls the load of the gasifier. Two different control approaches have been applied and investigated: one where the flow rate of the producer gas is fixed and the engine operates with varying excess of air due to variation in gas composition and thus stoichiometry, and a second where the excess of air in the exhaust gas is fixed and the flow rate of produced gas from the gasifier is varying. The interaction between the gas engine and the gasification system has been investigated. The engine and the plant are equipped with continuously data acquisition that monitors the operation including the composition of the producer gas and the flow. Producer gas properties and contaminations have been investigated. No detectable tar or particle content was observed, this was confirmed by three different measuring methods. An analysis of engine operation at varying load has been carried out. Standard emissions, load and efficiency have been measured at varying operating conditions ranging from 90% to 50% load. Relatively high emission of unburned CO was seen at all operating conditions when compared to the current regulation for CO emissions. Measurements of the PAH showed that there were no detectable PAH in exhaust gas from the engine when it is operated on producer gas. The emissions of aldehydes were measured to be significantly lower for producer gas operation than for natural gas.
Proceedings of Powertrain & Fluid Systems Conference & Exhibition: Sae Technical Paper, 2005
Main Research Area:
Investigation of Continuous Gas Engine Chp Operation on Biomass Producer Gas, 2005