Experimental Investigation of a Simulated Byproduct Fuel Mixture From the Cl-ODH Process in a Spark-Ignition Engine

Abstract

Abstract The study investigates a fuel mixture with ethane and methane as active species and a high dilution of CO2 for application in a spark-ignition (SI) engine. The simplified fuel mixture used is a byproduct of a chemical looping based oxidative dehydrogenation (Cl-ODH) process to convert ethane to ethylene. The byproduct gas mixture has a concentration of 41% CO2, 40% ethane, and 5% methane by weight along with other minor compounds. Varying mixtures of ethane and methane were selected and combined with between 42 to 46 percent by weight CO2 to evaluate the viability and efficiency of this fuel to operate in existing internal combustion engines as a means for reducing emissions and improving the process efficiency of the Cl-ODH process. An experimental test stand was built based on a 13 hp gasoline generator with modified gas induction. The engine was also instrumented for data acquisition from the engine. A gas metering and mixing system was installed to precisely control the mass of gases induced into the engine. Various instrumentation was installed on the engine to monitor in-cylinder pressure, temperature at various locations, emissions, and fuel and airflow rates. Varying loads were applied and flow rates of the gases were induced to simulate different mixtures. It was found that under a high load, the mixed gas was able to generate comparable thermal efficiency and power to gasoline. But under no load or a part load condition the indicated thermal efficiency was found to be lower than that of gasoline. Further, the mixed gas also resulted in lower CO and NOx emissions compared to gasoline. The application of this work is an alternative fuel for existing engines that with little modification can operate effectively and benefit the overall process of ethylene generation.