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This paper presents the concept of gasified diesel fuel as a potential solution to the diesel engine emissions problem, especially the particulates. The concept employs two-stage combustion. During the first stage of combustion diesel fuel is partially oxidized with air in a catalytic reactor and converted to a hydrogen-rich gas. During the second stage of combustion the hydrogen-rich gas is mixed with additional air and burned to completion in the engine. The first stage reaction is catalytic and when carried out at an air-fuel mass ratio of 5.2, it does not produce soot or particulates. The subsequent combustion of the hydrogen-rich gas in the engine does not form soot or particulates. The conversion of diesel fuel to a hydrogen-rich gas is an exothermic reaction. The energy released during the process can be recovered in a Rankine engine heat recovery unit to prevent a net loss in fuel economy.

This paper presents the concept of methanol decomposition using engine exhaust heat, and examines its potential for use in the operation of passenger cars, diesel trucks, and diesel-electric locomotives. Energy economy improvements of 10-20% are calculated over the representative driving cycles without a net loss in power. Some reductions in exhaust emissions are also projected.

The concept of using two-stage combustion in a spark ignition engine has been tested in a single cylinder CFR engine. The engine was operated over an equivalence ratio range of 1.5 to 2.2 to evaluate the first stage of combustion. The product gas was analyzed for H2, CO, CO2, and hydrocarbons. An atmospheric burner was operated with gasoline over the same equivalence ratio range of 1.5-2.2, and the resulting product gases were then burned in the CFR engine to test the second stage of combustion. Emissions of NOx, HC and CO of 0.1, 0.1, and 5 gm/IHP-hr were measured respectively. The engine indicated efficiency for the two-stage mode was essentially the same as for the single-stage mode.

The first engine dynamometer test results are presented for a modified fuel system based on hydrogen enrichment for a V-8 I.C. engine. The engine burns mixtures of gasoline and hydrogen under ultralean conditions to yield extreme low NOx emissions with increased engine efficiency. The hydrogen is produced in a compact onboard generator from gasoline and air. The hydrogen-rich product gas is cooled and mixed with the normal combustion air in a modified carburetor. The engine then operates in the conventional manner on atomized gasoline with spark ignition, but with hydrogen-enriched air and with a high spark advance of 40-50° BTDC. The engine thus receives two charges of fuel: a charge of gaseous fuel from the hydrogen generator, and the normal gasoline charge. The results on hydrogen enrichment are compared with the 1973 V-8 baseline stock engine with emission controls, and the same engine without controls and operated at a maximum efficiency under lean conditions.

A compact onboard hydrogen generator has been developed for use with a hydrogen-enriched gasoline internal combustion engine. The unit uses gasoline and air in a partial oxidation reactor to produce a gaseous product containing hydrogen, carbon monoxide, minor amounts of methane, carbon dioxide and water, and nitrogen. A study of the theoretical equilibrium product composition has indicated an optimum operating point at an air/fuel ratio of 5.15, where a hydrogen/fuel mass ratio of 0.136 can be obtained under soot-free conditions. This is based on a gasoline with an atomic hydrogen to carbon ratio of 1.92. Both thermal and catalytic reactors have been tested. The thermal unit requires a reaction temperature of 2400°F to obtain 80% of the theoretical hydrogen yield. Soot formation tends to be a problem. The catalytic reactor yields close to theoretical yields at an operating temperature of 1800°F without any soot formation. A commercial nickel catalyst is used.