Increasingly stringent legislation controls emissions from internal combustion engines to the point where alternative power sources for vehicles are necessary. The hydrogen fuel cell is one promising option, but the nature of the gas is such that the conversion of other fuels to hydrogen on board the vehicle is necessary. The conversion of methanol, methane, propane, and octane to hydrogen is reviewed. A combination of oxidation and steam reforming (indirect partial oxidation) or direct partial oxidation are the most promising processes. Indirect partial oxidation involves combustion of part of the fuel to produce sufficient heat to drive the endothermic steam reforming reaction. Direct partial oxidation is favored only at high temperatures and short residence times but is highly selective. However, indirect partial oxidation is shown to be the preferred process for all fuels. The product gases can be taken through a water–gas shift reactor, but still retain ∼2% carbon monoxide, which poisons fuel-cell ca...

Onboard fuel conversion for hydrogen-fuel-cell-driven vehicles

A comparative study of non-thermal plasma assisted reforming technologies

On-board generation of hydrogen-rich gaseous fuels—a review

The power generation system and method of the present invention employ a solid oxide fuel cell which reforms fuel to a degree which is controlled by the amount of fuel introduced to the solid oxide fuel cell. The effluent is directed preferably through a heat exchanger and then into an engine. This hybrid system more efficiently produces energy, both mechanical and electrical, over conventional systems.

Power generation system and method

Fuel reforming in internal combustion engines

A process and apparatus is described for producing a hydrogen rich gas by injecting air and hydrocarbon fuel at one end of a cylindrically shaped chamber to form a mixture, igniting the mixture to provide hot combustion gases, by partial oxidation of the hydrocarbon fuel. The combustion gases move away from the ignition region to another region where water is injected to be turned into steam by the hot combustion gases. The steam which is formed mixes with the hot gases present to yield a uniform hot gas whereby a steam reforming reaction with the hydrocarbon fuel takes place to produce a hydrogen rich gas.

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Hydrogen rich gas generator

A hydrogen generator provides hydrogen rich product gases which are mixed with the fuel being supplied to an internal combustion engine for the purpose of enabling a very lean mixture of that fuel to be used, whereby nitrous oxides emitted by the engine are minimized. The hydrogen generator contains a catalyst which must be heated to a pre-determined temperature before it can react properly. To simplify the process of heating up the catalyst at start-up time, either some of the energy produced by the engine such as engine exhaust gas, or electrical energy produced by the engine, or the engine exhaust gas may be used to heat up air which is then used to heat the catalyst.

/pdf/start-up-system-for-hydrogen-generator-used-with-an-internal-3vyrr14cp0.pdf

Start up system for hydrogen generator used with an internal combustion engine

On-board hydrogen generator for a partial hydrogen injection internal combustion engine

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 H/sub 2/, CO, CO/sub 2/, and hydrocarbons. An atmospheric burner was operated with gasoline over the same equivalence ratio range of 1.5 to 2.2, and the resulting product gases were then burned in the CFR engine to test the second stage of combustion. Emissions of NO/sub x/, 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.

D. J. Cerini

Papers

Hydrogen rich gas generator

Start up system for hydrogen generator used with an internal combustion engine

On-board hydrogen generator for a partial hydrogen injection internal combustion engine

Two-Stage Combustion for Low Emissions without Catalytic Convertors