James G. Hansel

Control of exhaust emissions from methane-fueled internal combustion engines

Nitrogen oxides and carbon monoxide are removed from the exhaust of an internal combustion engine which operates on a methane-containing fuel by reacting the carbon monoxide, nitrogen oxides, and oxygen in the exhaust gas with methane in the presence of a catalyst comprising a crystalline zeolite having a silicon to aluminum ratio of equal to or greater than about 2.5 which is exchanged with a cation selected from the group consisting of cobalt, nickel, iron, chromium, rhodium, gallium, and manganese. Methane for the reaction is provided as a portion of the methane-containing fuel.

Development of a Dimethyl Ether (DME)-Fueled Shuttle Bus

Dimethyl Ether (DME) is a potential ultra-clean diesel fuel. Its unique characteristics require special handling and accommodation of its low viscosity and low lubricity. In this project, DME was blended with diesel fuelto provide sufficient viscosity and lubricity to permit operation of a 7.3 liter turbodiesel engine in a campus shuttle bus with minimal modification of the fuel injection system. A pressurized fuel delivery system was added to the existing common rail injection system on the engine, allowing the DME-diesel fuel blend to be circulated through the rail at pressures above 200 psig keeping the DME in the liquid state. Fuel exiting the rail is cooled by finned tubed heat exchangers and recirculated to the rail using a gear pump. A modified LPG tank (for use on recreational vehicles) stores the DME- diesel fuel blend onboard the shuttle bus. A small cylinder of helium is used to provide a blanket of inert gas above the fuel mixture to keep the DME in the liquid state and to push the mixture to the fuel rails. A significant challenge is posed by the rapid increase in DME vapor pressure with increasing fuel temperature. As the fuel mixture passes through the rail, it is heated by the surrounding surfaces in the cylinder head. The target for maximum fuel rail temperature was set at 50°C, which corresponds to a DME vapor pressure of 150 psig. Refueling was accomplished by mixing the diesel fuel and DME onboard the bus, with diesel fuel delivered from the existing diesel tank and DME delivered by 1000 Ib cylinders at a small refueling station. The shuttle bus operates on the Faculty/Staff loop at the University Park campus of the Pennsylvania State University.

Oxygen compatibility of high-surface-area materials

High-surface-area metallic structured packings are finding increasing use in the cryogenic distillation of air. An experimental program was performed to determine the oxygen compatibility of selected metals under the high-surface-area-to-volume ratios and adiabatic conditions encountered in commercial use. Under some conditions brass packing unexpectedly had a higher relative flammability than aluminum, which is contrary to reported test results using metal rods and strips. This is due, we believe, to the specific geometric and adiabatic configuration of the packing material which appears to enhance the propagation of combustion in brass. Aluminum flammability in gaseous oxygen has been shown to be very dependent upon argon dilution and, in the presence of liquid oxygen, strong energy releases have been observed, similar to those experienced with aluminum powder and liquid oxygen. Copper was found to be nonpropagating in all tested oxygen purities. These findings suggest that results from oxygen compatibility tests on rods and strips cannot be used reliably for ranking the suitability of materials in high-surface-area-to-volume ratio and adiabatic configurations.

Oxygen fireflooding: combustion tube tests with light, medium, and heavy crude oils

Oxygen fireflooding as a means of enhanced oil recovery is receiving increased evaluation in the laboratory and in pilot field tests. As in the case of air fireflooding, the combustion tube can play an important role in understanding some of the parameters of oxygen fireflooding for a variety of crude oils. A total of five light, medium, and heavy crude oils was evaluated in a combustion tube primarily at 750 and 2000 psig and with oxygen concentrations between 21% (air) and 95%. As was reported in a previous paper, which was concerned with a light oil only, the overall characteristics of the combustion with oxygen appear to be superior to the characteristics with air. For light and medium crude oils, when the combustion conditions are marginal (e.g., at low temperature for which the kinetics appear to control the coke combustion) the apparent kinetics and the quality of the combustion were substantially improved when oxygen enrichment was utilized.