Investigators are studying hydrogen purification by membrane technology as a means to make the coal-to-hydrogen route economically attractive. To allow prediction of membrane performance and to facilitate comparisons between membrane and other technologies (cryogenic distillation, pressure swing adsorption), they developed a mathematical model to describe the permeation process inside a membrane module. The results of this model were compared with available experimental data (separation of CO{sub 2}/O{sub 2}/N{sub 2} mixtures). The model was first used to calculate the gas permeabilities from one set of mixed-gas experiments; the resulting permeabilities were then used to predict the results of the other mixed-gas experiments. The agreement between these predictions and the experimental data was good. However, model predictions using gas permeabilities obtained in pure gas experiments did not agree with the mixed gas experimental data. This disagreement is believed to be due to plasticization of the membrane by contact with CO{sub 2}. These results indicate that data obtained from experiments with mixed-gas feeds are necessary to adequately predict membrane performance when CO{sub 2} is present. The performance of different system configurations, including one and two stages of membrane modules, was examined. The different configurations examined were single module (SM), single module with recycle …

Investigators are studying hydrogen purification by membrane technology as a means to make the coal-to-hydrogen route economically attractive. To allow prediction of membrane performance and to facilitate comparisons between membrane and other technologies (cryogenic distillation, pressure swing adsorption), they developed a mathematical model to describe the permeation process inside a membrane module. The results of this model were compared with available experimental data (separation of CO{sub 2}/O{sub 2}/N{sub 2} mixtures). The model was first used to calculate the gas permeabilities from one set of mixed-gas experiments; the resulting permeabilities were then used to predict the results of the other mixed-gas experiments. The agreement between these predictions and the experimental data was good. However, model predictions using gas permeabilities obtained in pure gas experiments did not agree with the mixed gas experimental data. This disagreement is believed to be due to plasticization of the membrane by contact with CO{sub 2}. These results indicate that data obtained from experiments with mixed-gas feeds are necessary to adequately predict membrane performance when CO{sub 2} is present. The performance of different system configurations, including one and two stages of membrane modules, was examined. The different configurations examined were single module (SM), single module with recycle …

The K-700 Power House area, initially built to supply power to the K-25 gaseous diffusion plant was shutdown and disassembled in the 1960s. This shutdown was initiated by TVA supplying economical power to the diffusion plant complex. As a result of world wide over production of enriched, reactor grade U{sup 235}, the K-27 switch yard and switch house area was placed in standby in 1985. Subsequently, as the future production requirements decreased, the cost of production increased and the separation technologies for other processes improved, the facility was permanently shutdown in December, 1987. This Site Characterization Report is a part of the FY-88 engineering Feasibility Study for placing ORGDP Gaseous Diffusion Process facilities in 'Permanent Shutdown'. It is sponsored by the Department of Energy through Virgil Lowery of Headquarters--Enrichment and through Don Cox of ORO--Enrichment Operations. The primary purpose of these building or site characterization reports is to document, quantify, and map the following potential problems: Asbestos; PCB containing fluids; Oils, coolants, and chemicals; and External contamination. With the documented quantification of the concerns (problems) the Engineering Feasibility Study will then proceed with examining the potential solutions. For this study, permanent shutdown is defined as the securing and/or conditioning of …

A series of mass transfer studies were conducted for the extraction of solute from droplets falling in an electric field. The experiments were planned such that the dispersed phase resistance was controlling. In one series of experiments single drops were formed from a charged nozzle and allowed to fall through a continuous, dielectric phase. The drop size and velocity were correlated by means of a simple force balance. Drop mass transfer coefficients were calculated for the drop free fall period and were compared to predictions based upon literature correlations for an oscillating droplet in-the absence of an electric field. Droplet size and velocity were approximately predicted by a staple force balance whereas the mass transfer coefficient was approximately 25--250% higher than that predicted. Droplet extraction efficiencies Increased about 20--30% in the presence of electric fields up to 2 kv/cm. For the same field, the drop diameter decreased 30--50% and the terminal velocity increased by up to 50%. The enhancements for the toluene-water system can be ascribed to increases in terminal velocity and decreases in drop diameter. The mass transfer model for freely falling drops proposed by Skelland and Wellek roughly predicts the moderate mass transfer efficiency increases (about 18% at …

A series of mass transfer studies were conducted for the extraction of solute from droplets falling in an electric field. The experiments were planned such that the dispersed phase resistance was controlling. In one series of experiments single drops were formed from a charged nozzle and allowed to fall through a continuous, dielectric phase. The drop size and velocity were correlated by means of a simple force balance. Drop mass transfer coefficients were calculated for the drop free fall period and were compared to predictions based upon literature correlations for an oscillating droplet in-the absence of an electric field. Droplet size and velocity were approximately predicted by a staple force balance whereas the mass transfer coefficient was approximately 25--250% higher than that predicted. Droplet extraction efficiencies Increased about 20--30% in the presence of electric fields up to 2 kv/cm. For the same field, the drop diameter decreased 30--50% and the terminal velocity increased by up to 50%. The enhancements for the toluene-water system can be ascribed to increases in terminal velocity and decreases in drop diameter. The mass transfer model for freely falling drops proposed by Skelland and Wellek roughly predicts the moderate mass transfer efficiency increases (about 18% at …

Weekly report of the Texas Agricultural Statistics Service on broiler chick numbers in Texas and compared with other states. It includes compiled statistics across six consecutive weeks, from the week ending December 5 to the week ending January 9, during 1986, 1987, and 1988 for broiler eggs set, chicks hatched, and chicks placed.

The {sup 235}U content in fuel tubes (g{sup 235}U/ft) is directly proportional to the {sup 235}U concentration (g{sup 235}U/cc) in the U-Al core alloy. In order to prepare enriched uranium metal, aluminum, and U-Al scrap for U-Al production melts, the overall alloy composition (wt % U-Al) must be calculated for the desired {sup 235}U concentration (g{sup 235}U/cc) and uranium enrichment (*wt % {sup 235}U). This memorandum documents an alternative equation for calculation of U-Al alloy casting compositions in Building 321-M. This equation confirms the results of another, undocumented equation that has been used in the past.

Results are presented for control rod worth experiments in the axially heterogeneous assembly ZPPR-17, a part of the JUPITER-III program. From the earlier metal-fuel ZPPR-15 program, results are given for measurements and calculations of neutron spectra and sodium voiding in several configurations.

This report discusses the reauthorization of most Federal elementary and secondary education programs, which the 100th Congress is currently considering, as well as the creation of several new programs. Issues have included: (1) Federal versus ~tate/local priorities in the use of funds; (2) use of formula grants or competitive grants to allocate funds; (3) services for eligible nonpublic school children; (4) relationship between Federal programs and State-level school reform activities; and (5) information about programs and participants for the Congress.