Quarterly report discussing fuel cell research and development work at Argonne National Laboratory (ANL). This report describes efforts directed toward (1) investigating alternative concepts for components of molten carbonate fuel cell stacks and (2) improving our understanding of component behavior.

The aqueous biphasic extraction (ABE) process for soil decontamination involves the selective partitioning of solutes and fine particulates between two immiscible aqueous phases. The biphase system is generated by the appropriate combination of a water-soluble polymer (e.g., polyethylene glycol) with an inorganic salt (e.g., sodium carbonate). Selective partitioning results in 99 to 99.5% of the soil being recovered in the cleaned-soil fraction, while only 0.5 to 1% is recovered in the contaminant concentrate. The ABE process is best suited to the recovery of ultrafine, refractory material from the silt and clay fractions of soils. During continuous countercurrent extraction tests with soil samples from the Fernald Environmental Management Project site (Fernald, OH), particulate thorium was extracted and concentrated between 6- and 16-fold, while the uranium concentration was reduced from about 500 mg/kg to about 77 mg/kg. Carbonate leaching alone was able to reduce the uranium concentration only to 146 mg/kg. Preliminary estimates for treatment costs are approximately $160 per ton of dry soil. A detailed flowsheet of the ABE process is provided.

This report discusses the results of the environmental protection program at Argonne National Laboratory-East (ANL) for 1990. To evaluate the effects of ANL operations on the environment, samples of environmental media collected on the site, at the site boundary, and off the ANL site were analyzed and compared to applicable guidelines and standards.

A technique for incorporating automatic transformations into processes such as the application of inference rules, subsumption, and demodulation provides a mechanism for improving search strategies for theorem proving problems arising from the field of program verification. The incorporation of automatic transformations into the inference process can alter the search space for a given problem, and is particularly useful for problems having broad rather than deep proofs. The technique can also be used to permit the generation of inferences that might otherwise be blocked and to build some commutativity or associativity into the unification process. Appropriate choice of transformations, and new literal clashing and unification algorithms for applying them, showed significant improvement on several real problems according to several distinct criteria.

The bilinear cyclic stress-strain parameters for Types 304 and 316 stainless steel are described. The bilinear properties of solution-annealed and aged Type 304 stainless steel (heat 9T2796) and solution-annealed Type 3l6 stainless steel (heat 8092297) under cyclic-loading conditions at a strain rate of 8.6 x 10⁵ s⁻¹, total strain range between 0.2 and 0.8 percent, and temperatures from 22 to 593 degrees C were determined. The dependence of bilinear parameters on maximum strain epsilon and temperature is discussed.

In this report it is shown that a burner placed in a combustible fluid can have a stabilizing effect on a plane flame. A mathematical model is derived in which the flame is modeled as a surface of discontinuity in the flow field. Jump conditions for the fluid variables, as well as an expression for the flame speed, are obtained from an asymptotic analysis of the detailed structure of the flame. The model is applied to investigate the linear stability of a plane flame. Stable behavior is shown to exist for certain regimes of the parameters: Lewis number, burner strength, heat release and inflow velocity.

By means of the unsteady-flow theory and a bilinear mathematical model, a theoretical study was conducted of the chaotic dynamics associated with the fluid-elastic instability of loosely supported tubes. Calculations were performed for the RMS of tube displacement, bifurcation diagram, phase portrait, power spectral density, and Poincare map. Analytical results show the existence of chaotic, quasi-periodic, and periodic regions when flow velocity exceeds a threshold value.

Report describing the research and development activities related to reactor fuels and fast-reactor programs conducted by the Argonne National Laboratory Chemical Engineering Division.

A fused fluoride process for dissolution of zirconium-uranium fuel alloys is being developed. The alloy is dissolved in an equimolar sodium fluoride-zirconium fluoride melt at 600°C by sparging the system with hydrogen fluoride. The uranium is volatilized from the melt as the hexafluoride by a sparging operation with fluorine or bromine pentafluoride vapor. This product is then decontaminated and purified by fractional distillation.

An analysis has been made of the combined motion of fuel and coolant due to fuel-coolant interactions following a massive fuel failure in a high-ramp overpower transient. The motion of fuel and coolant was described using a two-fluid model formulation in which the mixture of sodium liquid and vapor and of fission gas, on the one hand, and the fuel particles, on the other, were treated as two superimposed continua. The method of solution employed a numerical procedure called the ACE method, a modified version of the IMF technique.

The COMMIX-1AR/P computer code is designed for analyzing the steady-state and transient aspects of single-phase fluid flow and heat transfer in three spatial dimensions. This version is an extension of the modeling in COMMIX-1A to include multiple fluids in physically separate regions of the computational domain, modeling descriptions for pumps, radiation heat transfer between surfaces of the solids which are embedded in or surround the fluid, a k-{var epsilon} model for fluid turbulence, and improved numerical techniques. The porous-medium formulation in COMMIX allows the code to be applied to a wide range of problems involving both simple and complex geometrical arrangements. The basic equations, underlying assumptions, and solution techniques are presented for the entire computer code, covering both old and new features.

In 1978, a conceptual design of a 100 MW-h load-leveling battery system having Li alloy/FeS cells was developed as a result of a joint effort between ANL and Rockwell International. Most of this cost was contributed by the submodule structure and the charge equalization scheme, which was the same as that developed for electric-vehicle batteries.

Report issued by the Argonne National Laboratory over "the use of an electromagnetic field to control the laminar film condensation of a vapor whose liquid is electrically conducting" (p. 7). This report includes tables, and illustrations.

A plutonium-aluminum alloy containing 4 atom per cent aluminum showed no attack after exposure to purified NaK for one month at 400 C in the absence of any oxide. The same specimen and other plutonium alloys, including pure plutonium, showed marked deterioration in shorter exposure in the presence of oxide films from a welded stainless steel container. Pure uranium was resistant even in the presence of such oxides.

Report concerning the corrosion of several ternary zirconium alloys using distilled water at 350 degrees Celsius or ssteam heated to 540 degrees Celsius and 600 psi.

Report issued by the Argonne national Laboratory discussing a technical and economic evaluation of a direct-cycle light-water boiling reactor designed for natural circulation and internal steam-water separation. The reference 100-Mw(e) reactor power plant design evolved from the study should have the best chance (compared to similar plants) of approaching the 8 to 9 mill/kwh total power-cost level. This report includes tables, and illustrations.

The creep-fatigue life results for five different heats of Type 304 stainless steel at 593 degrees C (1100 degrees F), generated under push-pull conditions in the axial strain-control mode, are presented. The life predictions for the various heats based on the linear-damage rule, strain-range partitioning method, and damage-rate approach are discussed. The appropriate material properties required for computation of fatigue life are also included.

Borosilicate glass is to be used for permanent disposal of high-level nuclear waste in a geologic repository. Mechanistic chemical models are used to predict the rate at which radionuclides will be released from the glass under repository conditions. The most successful and useful of these models link reaction path geochemical modeling programs with a glass dissolution rate law that is consistent with transition state theory. These models have been used to simulate several types of short-term laboratory tests of glass dissolution and to predict the long-term performance of the glass in a repository. Although mechanistically based, the current models are limited by a lack of unambiguous experimental support for some of their assumptions. The most severe problem of this type is the lack of an existing validated mechanism that controls long-term glass dissolution rates. Current models can be improved by performing carefully designed experiments and using the experimental results to validate the rate-controlling mechanisms implicit in the models. These models should be supported with long-term experiments to be used for model validation. The mechanistic basis of the models should be explored by using modern molecular simulations such as molecular orbital and molecular dynamics to investigate both the glass structure and …

A complete set of optical oscillator strengths and electron-impact cross sections for the argon atom is presented in tabular form. A large variety of experimental data and theoretical calculations was studied, and various checks based on theory (including the constraint of sum rules) were critically performed. Data were analyzed mainly by a semi-empirical method that stresses the close relation of photoabsorption with electron-atom collisions.

ANL has decontaminated and decommissioned (D and D) seven radiologically contaminated surplus facilities at its Illinois site: a ''Hot'' Machine Shop (Building 17) and support facilities; Fan House No. 1 (Building 37), Fan House No. 2 (Building 38), the Pangborn Dust Collector (Building 41), and the Industrial Waste Treatment Plant (Building 34) for exhaust air from machining of radioactive materials. Also included were a Nuclear Materials Storage Vault (Building 16F) and a Nuclear Research Laboratory (Building 22). The D and D work involved dismantling of all process equipment and associated plumbing, ductwork, drain lines, etc. After radiation surveys, floor and wall coverings, suspended ceilings, room partitions, pipe, conduit and electrical gear were taken down as necessary. In addition, underground sewers were excavated. The grounds around each facility were also thoroughly surveyed. Contaminated materials and soil were packaged and shipped to a low-level waste burial site, while nonactive debris was buried in the ANL landfill. Clean, reusable items were saved, and clean metal scrap was sold for salvage. After the decommissioning work, each building was torn down and the site relandscaped. The project was completed in 1985, ahead of schedule, with substantial savings.

Report of highlights of Argonne program on the development of lithium/metal sulfide batteries. These batteries are being developed for electric-vehicle propulsion and for stationary energy-storage applications.

The purpose of this work was to study reagents which might be effective in dissolving uranium oxide produced during slug failures in water-cooled reactor systems. An aspect of this problem which has subsequently become of primary importance is the solubility or transportability of the oxide in pure water.

Various types of austenitic stainless steel (SS) were aged for up to 2500 h at a temperature of 600C to determine whether the resultant microstructural changes would affect the ultrasonic velocity and attenuation and thus the reliability of ultrasonic in-service inspections. Samples of Type 304 and 316 SS as well as 308, 308CRE, and 316 weld metal were examined. Velocity variations were less than 1%, and attenuation variations at frequencies below 10 MHz were not significant except in the anomalous case of one Type 316 SS weldmetal sample. That change may be due to unexpected microstructural changes associated with aging. The variation in the samples attributed to aging is therefore not expected to have a deleterious effect on ultrasonic in-service inspection of stainless steel reactor components.

Performance of improved Ni/Fe electric vehicle batteries was measured at ambient temperatures of 0, 25, and 50 C for a range of overcharge levels, open-circuit stand times, and charge and discharge rates. Tests in which charges and discharges were performed at different battery operating temperatures showed that the discharge capacity of a Ni/Fe battery is directly related to its operating temperature, but its charge acceptance is decreased at 0 and 50 C by approx. 6% from that obtained at 25 C. The decline in battery efficiency at high temperatures is the result of increased self-discharge losses. In the first 0.5 h after charge, the Ah self-discharge loss at 50 C is twice (6%) that at 0 and 25 C (approx. 3%), corresponding to an increase in initial self-discharge rate from approx. 8 to 16 A. The increased self-discharge rate apparently occurs during the latter part of charging and, thereby, causes the 6% decline in charge acceptance. A decrease in battery efficiency also resulted at 50 C (6% coulombic and 4% energy efficiency loss) when the charge current was reduced from the 3-h to the 6-h rate. In comparison, low temperatures impact battery internal resistance and IR-free voltage more than high …