Recently, a number of processes producing the synthesis gas from the natural gas by partial oxidation are reported, and some of them are developed to the industrial scale. The authors have interest in such partial oxidation through combustion reaction in an engine combustion chamber considering it as a sort of reactor, and performed some calculations to ascertain the extent of gas conversion with this process.
Since the natural gas consists of almostly methane, we assumed the resultant gas of partial oxidation of it with oxygen would contain carbon-monoxide, carbon-dioxide, steam, hydrogen, methane and oxygen. Thence, applying the material balance, heat balance and equilibrium relations among those resultant gaseous components, we could find necessary figures, such as adiabatic combustion temperature, exhaust gas temperature, its composition, thermal efficiency and the power output that could be recovered from the engine.
It is shown that extreme rich mixture near the upper limit of inflammability gives suitable gas composed of essentially hydrogen and carbon-monoxide, and the sum of them reaches up to 86-88% having the ratio of the former to the latter as high as 1.8. At the same time, although thermal efficiency is rather low as 6.5-7.0%, owing to the extreme rich mixture condition, available power output amounts to 0.65-0.70kWh per normal cubic meter of fee methane.
Such an engine process manufacturing the synthesis gas with additional gain of power seems to be very hopeful as far as theoretical calculation is concerned.
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