Combustion of Fuel Hydrates

University Of California-Irvine, Irvine CA

Investigators

Abstract

AWARD Abstract Proposal Title: Combustion of Fuel Hydrates Principal Investigator: Dunn-Rankin, Derek . Institution: University of California-Irvine Proposal No: CBET-0932415 This research focuses on the combustion science involved in burning gas hydrates, a major potential energy resource. Gas hydrates are ice-like crystalline solids that encapsulate guest gas molecules like methane. A significant storehouse of methane is in the form of methane hydrates on the sea floor and in the arctic permafrost. These fuel hydrates represent an important intersection of energy and environmental concerns. Methane has a beneficial potential impact on climate change as a fuel because it makes less CO2 than any other hydrocarbon, but if released, its negative impact is significant because unreacted methane is a powerful greenhouse gas. Combustion of hydrate deposits is being considered both to release the natural gas and for direct energy conversion. In addition, hydrates are being examined as efficient forms for storage and transport of natural gas. The potential fire hazards of such uses can be significant. This project will measure the combustion properties of methane, propane, and mixed gas hydrates. Although there is a broad scientific literature and understanding of the physical properties of hydrates and their formation kinetics, there is very little research on their combustion properties. Sample photographs of burning fuel hydrates demonstrate flammability, but these photographs contain none of the important standard combustion-behavior information. Fuel gas hydrates will be molded into pellets mounted on thin supports or dispersed as a snow. The hydrates will then be ignited for measuring key combustion properties such as surface regression rate, water melted versus evaporated, flame standoff distance, combustion temperatures and the formation of soot. The results will be contrasted with the classical results for the combustion of single-component droplets and porous-sphere diffusion flames. One of the key differences between conventional fuels and a hydrate form is that for hydrates the internal kinetics controlling gas release and diffusion to the surface are likely to be important. Beyond the focused contribution to graduate education and research, the project will reach and encourage younger students through three programs at the University of California Irvine: LSAMP (Alliance for Minority Participation), UROP (Undergraduate Research Opportunities), and COSMOS (Summer Science Camp). At least one LSAMP student will participate on the project each year, and undergraduate research is an integral part of the work. The burning ice experiments developed in this project will be used in the precollege UCI COSMOS program, a summer residential activity for talented high school students interested in science and technology.