Performances of a producer gas from sewage sludge gasification enriched with ammonia in a spark-ignition engine

Abstract

Syngas (Synthetic Gas), producer gas or wood gas, are gaseous fuels that could be produced by the gasification of biomass. It is mainly composed of hydrogen and carbon monoxide with a smaller share of methane, all diluted by nitrogen and carbon dioxide. Although it contains carbon in its composition, it is considered as a low or zero carbon fuel as soon as it is made from biomass, which makes it a strong candidate for reducing the global warming impact of combustion engines. This work focuses on the combustion development and performances of a Spark-Ignition engine, fuelled with a synthetic producer gas enriched with ammonia, from a nitrogen-rich sample, typical of ammonia-enriched sewage sludge. Results show that, by replacing part of the producer gas by ammonia, the indicated work increases and the combustion development is slowed down. Last exhaust emissions measurement shows a decrease in CO and CO2 as a function of ammonia addition in the fuel thus showing that ammonia does not influence the combustion efficiency for the carbon species. Yet a noticeable increase of NOx is observed when adding ammonia to the fuel.