Results of an experimental investigation into the extent of methane conversion when introduced in extremely small concentrations down to around a fraction of one percent by volume into the intake of a swirl chamber diesel engine are presented. Such an approach represents effectively an unconventional dual fuel engine operation with exceptionally lean gaseous fuel mixtures but combined with unusually very large diesel fuel pilot quantities.
It is to be shown that for wide ranges of gas admission concentrations, diesel fuel quantity injected, load and speed that much of the methane added did get oxidized in the indirect injection engine to an extent from 53% to 80%, to appear in the form of carbon dioxide while contributing at the same time to the power output. Such methane admission tended to increase carbon monoxide exhaust emissions slightly, indicating that part of the methane may not have been fully oxidized. However, among the methane converted by engine combustion, about 80% is converted completely to carbon dioxide.
It is suggested that such an approach converts the highly strong greenhouse gas methane into carbon dioxide, a much weaker greenhouse gas. Moreover, such an approach appears more effective than attempts made to dispense of any fugitive methane gas discharges into the compressor intake air of an industrial gas turbine. The implication of such performance results to dual fuel engine combustion is also highlighted.