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Tapered fluidized-bed bioreactor: an improved device for continuous cultivation

Description: The bioreactor concept utilizing a tapered fluidized bed has shown considerable promise for use in bioprocesses where the biological agents can be immobilized on a fluidizable solid phase, but the operating characteristics of such a reactor are not yet fully understood. A simple mathematical model (steady state, plug flow conditions) has been developed and tested with experimental data, and calculated values compare favorably with experimental values. A more complete and presumably more valid m… more
Date: January 1, 1978
Creator: Pitt, Jr., W. W.; Hancher, C. W.; Scott, C. D. & Hsu, H. W.
Partner: UNT Libraries Government Documents Department
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Packed bed reactor treatment of liquid hazardous and mixed wastes

Description: We are developing thermal-based packed bed reactor (PBR) technology as an alternative to incineration for treatment of hazardous organic liquid wastes. The waste streams targeted by this technology are machining fluids contaminated with chlorocarbons and/or chlorofluorocarbons and low levels of plutonium or tritium The PBR offers several distinct advantages including simplistic design, rugged construction, ambient pressure processing, economical operations, as well as ease of scalability and ma… more
Date: January 1, 1992
Creator: Tennant, R.A.; Wantuck, P.J. & Vargas, R.
Partner: UNT Libraries Government Documents Department
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C-CAMP, A closed cycle alkali metal power system

Description: A concept is presented for a Closed-Cycle Alkali Metal (C-CAMP) power systems which utilizes the heat of reaction of an alkali metal and halogen compound to vaporize an alkali metal turbine fluid for a Rankine cycle. Unique features of the concept are (1) direct contact (heat exchange) between the reaction products and turbine fluid, and (2) a flow-through chemical reactor/boiler. The principal feasibility issues of the concept relate to the degree of cross-mixing of product and turbine fluid s… more
Date: January 1, 1988
Creator: Wichner, R. P. & Hoffman, H. W.
Partner: UNT Libraries Government Documents Department
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PREMATH: a Precious-Material Holdup Estimator for unit operations and chemical processes

Description: A computer program, PREMATH (Precious Material Holdup Estimator), has been developed to permit inventory estimation in vessels involved in unit operations and chemical processes. This program has been implemented in an operating nuclear fuel processing plant. PREMATH's purpose is to provide steady-state composition estimates for material residing in process vessels until representative samples can be obtained and chemical analyses can be performed. Since these compositions are used for inventor… more
Date: January 1, 1982
Creator: Krichinsky, A.M. & Bruns, D.D.
Partner: UNT Libraries Government Documents Department
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Influence of irrigation and weathering reactions on the composition of percolates from retorted oil shale in field lysimeters

Description: Major cations, anions, trace elements and dissolved organic C were measured in percolate from retorted oil shale collected from irrigated lysimeters in the field at Anvil Points, Colorado, over a two year period. The investigations indicated that chemical equilibrium was not established over the monitoring period and major changes occurred in percolate composition as a function of applied water volume and water residence time in the shale. Field and laboratory studies indicated that several fac… more
Date: April 1, 1979
Creator: Garland, T. R.; Wildung, R. E. & Harbert, H. P.
Partner: UNT Libraries Government Documents Department
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Liquid metal reactions under postulated accident conditions for fission and fusion reactors

Description: Sodium and lithium reactions are considered in the context of a postulated breach of a coolant boundary. Specific topics addressed are coolant-atmosphere and coolant-material reactions which may contribute to the overall consequence of a postulated accident scenario, and coolant reaction extinguishment and effluent control which may be desirable for containment of the spilled coolant.
Date: April 1, 1980
Creator: Muhlestein, L.D.
Partner: UNT Libraries Government Documents Department
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Engineering aspects of hydrogen production from photosynthetic bacteria

Description: Certain photosynthetic bacteria (PSB), for example, Rhodopseudomonas capsulata, evolve hydrogen when placed in an anaerobic environment with light and a suitable organic substrate. An engineering effort to use such bacteria for large-scale hydrogen production from sunlight is described. A system to produce 28,000 m/sup 3//day (1 x 10/sup 6/ ft/sup 3//day) of hydrogen has been designed on a conceptual level and includes hydrogen cleanup, substrate storage, and waste disposal. The most critical c… more
Date: February 1, 1982
Creator: Herlevich, A. & Karpuk, M.
Partner: UNT Libraries Government Documents Department
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Operation of the radioactive acid digestion test unit

Description: The Radioactive Acid Digestion Test Unit (RADTU) has been constructed at Hanford to demonstrate the application of the Acid Digestion Process for treating combustible transuranic wastes and scrap materials. The RADTU with its original tray digestion vessel has recently completed a six-month campaign processing potentially contaminated nonglovebox wastes from a Hanford plutonium facility. During this campaign, it processed 2100 kg of largely cellulosic wastes at an average sustained processing r… more
Date: January 1, 1980
Creator: Blasewitz, A. G.; Allen, C. R.; Lerch, R. E.; Ely, P. C. & Richardson, G. L.
Partner: UNT Libraries Government Documents Department
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The application of time-resolved luminescence spectroscopy to a remote uranyl sensor

Description: Time resolved luminescence spectroscopy is an effective method for the determination of a wide range of uranyl concentrations in aqueous samples. We have applied this technique to the development of a remote sensing device using fiber optic cables coupled with a micro flow cell in order to probe for uranyl in aqueous samples. This sensor incorporates a Nafion membrane through which UO{sub 2}{sup 2+} can diffuse in to a reaction/analysis chamber which holds phosphoric acid, a reagent which enhan… more
Date: January 1, 1991
Creator: Varineau, P. T.; Duesing, R. & Wangen, L. E.
Partner: UNT Libraries Government Documents Department
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Determination of direct-acting mutagens and clastogens in oil shale retort process water

Description: Shale oil products contain various metabolically active and photoactive genotoxic components. In addition, preliminary observations indicated that retort process water contain direct-acting mutagens which cause significant increases in 6-thioguanine resistance (6TG/sup R/) mutants in Chinese hamster ovary (CHO) cells. However, we have been unable to demonstrate the occurrence of direct-acting mutagens in these process waters when tested in the standard Ames/Salmonella assay. In this report resu… more
Date: January 1, 1982
Creator: Chen, D.J.; Okinaka, R.T.; Strniste, G.F. & Meyne, J.
Partner: UNT Libraries Government Documents Department
open access

KINETIC MODELING OF A FISCHER-TROPSCH REACTION OVER A COBALT CATALYST IN A SLURRY BUBBLE COLUMN REACTOR FOR INCORPORATION INTO A COMPUTATIONAL MULTIPHASE FLUID DYNAMICS MODEL

Description: Currently multi-tubular fixed bed reactors, fluidized bed reactors, and slurry bubble column reactors (SBCRs) are used in commercial Fischer Tropsch (FT) synthesis. There are a number of advantages of the SBCR compared to fixed and fluidized bed reactors. The main advantage of the SBCR is that temperature control and heat recovery are more easily achieved. The SBCR is a multiphase chemical reactor where a synthesis gas, comprised mainly of H2 and CO, is bubbled through a liquid hydrocarbon wax … more
Date: September 1, 2008
Creator: Gribik, Anastasia; Doona Guillen, PhD & Daniel Ginosar, PhD
Partner: UNT Libraries Government Documents Department
open access

Inhalation toxicology of oil shale-related materials

Description: An effort was made to integrate industrial hygiene studies and chemical analyses with inhalation toxicology experiments in order to identify the pulmonary hazards that may arise from an oil shale industry. Results indicate that raw shale dusts cause very little epithelial or fibrotic reaction. Retorted shales elicit inflammatory reaction with varying degrees of fibrosis and epithelial hyperplasia. The shale dusts appear as agglomerations rather than as individual particles, with a peribronchiol… more
Date: January 1, 1979
Creator: Holland, L.M.; Spall, W.D. & Garcia, L.L.
Partner: UNT Libraries Government Documents Department
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A 1-D model for highly sensitive tubular reactors

Description: We consider the steady state operation of wall-cooled, fixed-bed tubular reactors. In these reactors the temperature rise ..delta..T must normally be limited to small fractions of the adiabatic temperature rise ..delta..T/sub ad/, both to avoid runaway and maintain product selectivity. Yet ..delta..T/..delta..T/sub ad/ << 1 can only occur if eta = t/sub dif//t/sub reac/ << 1, where t/sub dif/ is the timescale on which heat escapes the reactor by ''diffusing'' to the cooled walls, and t/sub reac… more
Date: January 1, 1987
Creator: Hagan, P. S.; Herskowitz, M. & Pirkle, J. C.
Partner: UNT Libraries Government Documents Department
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Extraction of plutonium from lean residues by room temperature fluoride volatility

Description: The use of dioxygen difluoride (FOOF) and KrF/sub 2/ for the recovery of Pu from lean residues by conversion to gaseous PuF/sub 6/ is being investigated. The greater stability of PuF/sub 6/ at room temperature allows much more extensive removal of Pu from contaminated wastes, when compared to the high temperature fluoride volatility process. The process also requires fewer additive chemicals than aqueous processes, thus minimizing the amount of material that must be disposed of as radioactive w… more
Date: January 1, 1989
Creator: Campbell, G. M.; Foropoulos, J.; Kennedy, R. C.; Dye, B. A. & Behrens, R. G.
Partner: UNT Libraries Government Documents Department
open access

Mechanistic model for void distribution in flashing flow

Description: A problem of discharging of an initially subcooled liquid from a high pressure condition into a low pressure environment is quite important in several industrial systems such as nuclear reactors and chemical reactors. A new model for the flashing process is proposed here based on the wall nucleation theory, bubble growth model and drift-flux bubble transport model. In order to calculate the bubble number density, the bubble number transport equation with a distributed source from the wall nucle… more
Date: January 1, 1987
Creator: Riznic, J.; Ishii, M. & Afgan, N.
Partner: UNT Libraries Government Documents Department
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Spontaneous emergence of a metabolism

Description: Networks of catalyzed reactions with nonlinear feedback have been proposed to play an important role in the origin of life. We investigate this possibility in a polymer chemistry with catalyzed cleavage and condensation reactions. We study the properties of a well-stirred reactor driven away from equilibrium by the flow of mass. Under appropriate non-equilibrium conditions. The nonlinear feedback of the reaction network focuses the material of the system into a few specific polymer species. The… more
Date: January 1, 1990
Creator: Bagley, R.J. & Farmer, J.D. (Los Alamos National Lab., NM (USA) Santa Fe Inst., NM (USA))
Partner: UNT Libraries Government Documents Department
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Biological denitrification of high-nitrates wastes generated in the nuclear industry

Description: Biological denitrification appears to be one of the most effective methods to remove nitrates from wastewater streams (Christenson and Harremoes, 1975). However, most of the research and development work has been centered on removal of nitrates from sewage or agricultural drainage waters, nitrate nitrogen concentration usually less than 50 g/m/sup 3/. Work was initiated at Oak Ridge National Laboratory (ORNL) in 1974 to test the use of biological nitrification in the removal of high concentrati… more
Date: January 1, 1980
Creator: Francis, C.W.
Partner: UNT Libraries Government Documents Department
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Cost comparison of solar detoxification with conventional alternatives for the destruction of trichloroethylene

Description: The purpose of this analysis is to compare the cost of solar waste detoxification processes with conventional alternatives for the treatment of trichloroethylene (TCE) in air. The solar processes that were evaluated are high flux photothermal oxidation (PHOTOX), high flux thermal catalytic reforming (SOLTOX), and low flux photocatalytic oxidation (PHOCAT). The high flux processes, PHOTOX and SOLTOX, were based on dish concentrator technology. The low flux photocatalytic process was based on par… more
Date: December 1, 1991
Creator: Glatzmaier, G.C.
Partner: UNT Libraries Government Documents Department
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Microwave production of hydrogen and sulfur from hydrogen sulfide wastes

Description: A waste-treatment process is being developed that uses cold'' microwave plasma-chemical reactions to split hydrogen sulfide into elemental hydrogen and sulfur. A clean sulfur product can be recovered and sold, while product gases are purified and separated into seams containing hydrogen, hydrogen sulfide for recycle, and the process purge containing carbon dioxide and water. Experiments with pure hydrogen sulfide at 0.5 to 1.5 L/min flow rates and microwave powers of 400 to 1000 W confirmed tha… more
Date: January 1, 1992
Creator: Harkness, J. B. L. & Doctor, R. D.
Partner: UNT Libraries Government Documents Department
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Explosive engineering problems from fragmentation tests in oil shale at the Anvil Points Mine, Colorado

Description: During 1981 and 1982, an extensive oil shale fragmentation research program was conducted at the Anvil Points Mine near Rifle, Colorado. The primary goals were to investigate factors involved for adequate fragmentation of oil shale and to evaluate the feasibility of using the modified in situ retort (MIS) method for recovery of oil from oil shale. The field test program included single-deck, single-borehole experiments to obtain basic fragmentation data; multiple-deck, multiple-borehole experim… more
Date: January 1, 1985
Creator: Dick, R.D.; Fourney, W.L. & Young, C.
Partner: UNT Libraries Government Documents Department
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Incorporation of chemical kinetic models into process control

Description: An important consideration in chemical process control is to determine the precise rationing of reactant streams, particularly when a large time delay exists between the mixing of the reactants and the measurement of the product. In this paper, a method is described for incorporating chemical kinetic models into the control strategy in order to achieve optimum operating conditions. The system is first characterized by determining a reaction rate surface as a function of all input reactant conce… more
Date: July 8, 1981
Creator: Herget, C.J. & Frazer, J.W.
Partner: UNT Libraries Government Documents Department
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Oxidation of hazardous waste in supercritical water: A comparison of modeling and experimental results for methanol destruction

Description: Recent experiments at Sandia National Laboratories conducted in conjunction with MODEC Corporation have demonstrated successful clean- up of contaminated water in a supercritical water reactor. These experiments targeted wastes of interest to Department of Energy production facilities. In this paper we present modeling and experimental results for a surrogate waste containing 98% water, 2% methanol, and parts per million of chlorinated hydrocarbons and laser dyes. Our initial modeling results c… more
Date: March 17, 1991
Creator: Butler, P. Barry; Bergan, Nina E.; Bramlette, T. Tazwell; Pitz, William J. & Westbrook, Charles K.
Partner: UNT Libraries Government Documents Department
open access

Solar reforming of methane in a direct absorption catalytic reactor on a parabolic dish

Description: The concept of solar driven chemical reactions in a commercial-scale volumetric receiver/reactor on a parabolic concentrator was successfully demonstrated in the CAtalytically Enhanced Solar Absorption Receiver (CAESAR) test. Solar reforming of methane (CH{sub 4}) with carbon dioxide (CO{sub 2}) was achieved in a 64-cm diameter direct absorption reactor on a parabolic dish capable of 150 kW solar power. The reactor was a catalytic volumetric absorber consisting of a multi-layered, porous alumin… more
Date: January 1, 1990
Creator: Muir, J.F.; Hogan, R.E. Jr.; Skocypec, R.D. (Sandia National Labs., Albuquerque, NM (USA)) & Buck, R. (Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Stuttgart (Germany, F.R.). Inst. fuer Technische Thermodynamik)
Partner: UNT Libraries Government Documents Department
open access

Solar reforming of methane in a direct absorption catalytic reactor on a parabolic dish: 2, Modeling and analysis

Description: The CAtalytically Enhanced Solar Absorption Receiver (CAESAR) experiment was conducted to determine the thermal, chemical, and mechanical performance of a commercial-scale, dish-mounted, direct catalytic absorption receiver (DCAR) reactor over a range of steady state and transient (cloud) operating conditions. The focus of the experiment is on global performance such as receiver efficiencies and overall methane conversion; it was not intended to provide data for code validation. A numerical mod… more
Date: January 1, 1991
Creator: Skocypec, R.D.; Hogan, R.E. Jr. & Muir, J.F.
Partner: UNT Libraries Government Documents Department
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