Summary of the Hanford Site Environmental Report for Calendar Year 2006 (open access)

Summary of the Hanford Site Environmental Report for Calendar Year 2006

This booklet summarizes the Hanford Site Environmental Report for Calendar Year 2006.
Date: September 15, 2007
Creator: Hanf, Robert W.; Poston, Ted M. & Dirkes, Roger L.
Object Type: Report
System: The UNT Digital Library
Surface CO2 leakage during the first shallow subsurface CO2release experiment (open access)

Surface CO2 leakage during the first shallow subsurface CO2release experiment

A new field facility was used to study CO2 migrationprocesses and test techniques to detect and quantify potential CO2leakage from geologic storage sites. For 10 days starting 9 July 2007,and for seven days starting 5 August 2007, 0.1 and 0.3 t CO2 d-1,respectively, were released from a ~;100-m long, sub-water table (~;2.5-mdepth) horizontal well. The spatio-temporal evolution of leakage wasmapped through repeated grid measurements of soil CO2 flux (FCO2). Thesurface leakage onset, approach to steady state, and post-release declinematched model predictions closely. Modeling suggested that minimal CO2was taken up by groundwater through dissolution, and CO2 spread out ontop of the water table. FCO2 spatial patterns were related to well designand soil physical properties. Estimates of total CO2 discharge along withsoil respiration and leakage discharge highlight the influence ofbackground CO2 flux variations on detection of CO2 leakagesignals.
Date: September 15, 2007
Creator: Lewicki, J. L.; Oldenburg, C.; Dobeck, L. & Spangler, L.
Object Type: Article
System: The UNT Digital Library
Framework for managing wastes from oil and gas exploration and production (E&P) sites. (open access)

Framework for managing wastes from oil and gas exploration and production (E&P) sites.

Oil and gas companies operate in many countries around the world. Their exploration and production (E&P) operations generate many kinds of waste that must be carefully and appropriately managed. Some of these wastes are inherently part of the E&P process; examples are drilling wastes and produced water. Other wastes are generic industrial wastes that are not unique to E&P activities, such as painting wastes and scrap metal. Still other wastes are associated with the presence of workers at the site; these include trash, food waste, and laundry wash water. In some host countries, mature environmental regulatory programs are in place that provide for various waste management options on the basis of the characteristics of the wastes and the environmental settings of the sites. In other countries, the waste management requirements and authorized options are stringent, even though the infrastructure to meet the requirements may not be available yet. In some cases, regulations and/or waste management infrastructure do not exist at all. Companies operating in these countries can be confronted with limited and expensive waste management options.
Date: September 15, 2007
Creator: Veil, J. A.; Puder, M. G. & Division, Environmental Science
Object Type: Report
System: The UNT Digital Library
Dense Membranes for Anode Supported all Perovskite IT-SOFCs (open access)

Dense Membranes for Anode Supported all Perovskite IT-SOFCs

Innovative wet chemical synthetic techniques were employed to obtain highly ionic conducting dense perovskites, mixed conducting porous perovskites, and electronically conducting perovskite membranes to be as electrolyte, cathode, anode, and interconnect for assembling all perovskite IT-SOFC system. Processing conditions were optimized to obtain well sintered LSM, LSF, LSCF, LNF, and LCF for SOFC cell and stacks working at 600-800 C. Series of nanocrystalline bulk and thin films of La{sub 0.8}Sr{sub 0.2}Ga{sub 0.83}Mg{sub 0.17}O{sub 2.815}, LaSr{sub 0.2}Fe{sub 0.8}O{sub 3}, LaSr{sub 0.2}Co{sub 0.8}Fe{sub 0.2}O{sub 3}, La{sub 0.8}Ni{sub 0.7}Fe{sub 0.3}O{sub 3}, LaCr{sub 0.7}Fe{sub 0.3}O{sub 3} were prepared at very low temperatures and characterized using XRD, SEM, HRTEM, XPS, EXAFS, and EIS techniques. The influence of preparation techniques on the microstructure, grain-size and consequently on the electrical transport properties were investigated. Processing conditions, sintering temperature (1200-1500 C) and time severely affected the grain size (< 0.1 {micro}m to 10 {micro}m) and the resistance in all grain-boundary (3 k{Omega} to175 k{Omega}). Through investigations of A and B site doping in perovskite materials, we have reduced cathode-electrolyte interfacial resistance, will be very effective for the SOFCs operating {approx} 750 C. Epitaxial films of LiFeNiO{sub 3}, for SOFCs cathode were deposited on LaAl{sub 2}O{sub 3}, MgO, and …
Date: September 15, 2007
Creator: Bobba, Rambabu
Object Type: Report
System: The UNT Digital Library