Abstract: A fuel comprising natural gas modified by the addition of hydrogen in appropriate proportions to produce a mixture with a burn rate that matches the burn rate of the gasoline is provided for burning in a gasoline engine without the need for modifications in engine timing, combustion chamber geometry, or other engine design parameters. A mixture of natural gas and nitrogen is also used to increase the knock limit on the power curve of fumigated diesel (compression ignition) engines and to increase the lean burn limit in spark ignition engines.

Abstract: A flame-type gas burner, having a burner head adapted to be attached to a source of supply of a fuel gas (specifically hydrogen) and one or more jet burner orifices in the head, has each jet orifice closely covered by sufficient steel wool, preferably stainless steel wool, from a mass of such wool contiguous to the burner head to significantly reduce formation of nitrogen oxides during combustion. Openings are provided in the assembly for flow of atmospheric combustion air through the mass of steel wool during burning of the gas. The gas burner itself may be any one of the many varieties of flame-type burners that are in common use for cooking, space heating and other utility purposes. A novel method of burning fuel gas is involved.