The feasibility of removing and recovering cesium-137 from various HAPO process solutions by precipitation of Cs2ZnFe(CN)6 has been demonstrated previously. Pilot plant studies of calcination and steam hydrolysis of non-radioactive Cs2ZnFe(CN)6 precipitates by members of the Process Equipment Development Operation are currently in progress. In support of these pilot plant studies, experiments were performed to determine the extent, if any, to which cesium volatilizes during calcination and hydrolysis of Cs2ZnFe(CN)6 precipitates containing cesium-137. Experimental procedures and results are presented in this report.

This report discusses the mathematical and statistical questions concerned with the estimation of a leak rate from data collected during a reactor containment vessel pressure test such as that performed on the PRTR vessel in May, 1959. A mathematical method is suggested in Section 3 for the construction of a total number of gas molecules in the containment vessel time series using vessel absolute pressure and temperature readings at several positions within the vessel. A formula for the precision of the series is given in terms of the individual instrument precisions. The question of accuracy and its relationship to the temperature gradient within the vessel is also considered.

The work described was undertaken to provide data for nuclear safety studies concerning NPF reprocessing equipment. The original objective was to determine the uranium density and water (hydrogen) content of UO2-H2O mixtures ranging from compact centrifuge cakes to dilute slurries. The scope was later expanded to include mixtures of UO2 with hydrocarbon oil and mixtures of UO3-H2O.

The need for criticality control in the proposed reprocessing of slightly enriched non-production fuels at Hanford has led to the development of a geometrically "safe", vertical tube, recirculating dissolver. A study of the nitric acid dissolution of uranium dioxide in a pilot plant dissolver of this type is reported here. The study was pointed toward the comparison of uranium dioxide dissolution rates in a batch and a recirculating dissolver and the definition of hydraulic problems associated with the recirculation of nitric acid, by air lift, technique through beds of reacting uranium dioxide.

The result of a leak in a PRTR process tube between the flow monitor and the heated section would be to increase the flow through the monitor, but to decrease the flow through the heated section. The concern for the case of small leaks is whether the increase in flow through the flow monitor is sufficient to cause a high flow tip and a reactor scram for the condition where the flow through the heated section is reduced to the point to cause excessive fuel element temperatures.

The components for the present aluminum clad, Al-Si bonded, internally and externally cooled (I & E), uranium fuel elements are composed of impact extruded cans and spire caps as shown in Figure 1. This type of component requires two impact extrusions; however, in December, 1957, J. E. Ruffin proposed another design of component in which there was only one impact extrusion. For this component, Figure 2, the spire was impact extruded as a part of the can.

A study and tests of the feasibility and best method of reaming rear face Parker fittings has been made. Flow increase of 8 percent, based on maintaining the same front header pressure, can be obtained at B, D, and F reactors by reaming the rear Parker fittings to .610 inch and using existing rear face hardware. Tests indicate mechanical strength will not be significantly reduced, high frequency vibration will not be increased, and that methods of reaming are available.

The fabrication processes applied to nuclear fuels are subject to severe limitations because of the conditions imposed by the reactor environment. The combined problems of neutrons fluxes, high heat fluxes, corrosion by the coolant , and embrittlement by hydriding or similar reactions may be minimized through establishing rigorous materials and fabrication specifications for fuel and cladding.

Powder metallurgy is rapidly gaining importance as a means of fabricating nuclear fuel elements and other reactor components. It provides a convenient method for forming metals, unusual combinations of metals, and metal-ceramic combinations. The unique features of this technique which make it desirable for nuclear engineering purposes are the following:

In many cases of analysis of two-phase flow in systems, considerable computation or program time could be saved if the critical pressures ratio were known. If a reservoir or plenum pressure is fixed, the usual computational procedure involves the assumption of several critical pressures and the generation of several momentum terms to find the applicable critical pressure ratio and thereby the critical flow. The formulation of an equation of state make it possible to compute critical pressure ratios directly.

The amount of dry air or inert gas supplied to a "one pass" glove box ventilation system is proportional to the glove box inleakage. Most glove boxes in the 234r5 Building are equipped with sundry attachments, each contributing to the inleakage. No individual leak rate date is available for these auxiliary components in the "as installed" condition. Nor is the effect of time upon the leak rates known. Knowledge of these values, or at least an indication of the order of magnitude of the leakage attributable to each item, would provide a basis for analyzing glove box ventilation problems and for establishing criteria for new glove box designs.

Late in 1958 it became apparent that some fuel elements were failing in the Hanford reactors as a result of water entering through the weld. The mode of entry appeared to be first through a void in the weld, then through a non-wet area or a train of voids in the braze, and finally to the uranium core. Defective closures of a similar nature were also typical of many fuel elements which have failed in the autoclaving operation as shown in Figure 1.

The multi-purpose dissolver was designed to provide: 1. A critically safe vessel for dissolving uranium metal of enrichments up to one percent U-235. 2. A vessel which can be charged with fuel elements up to 10 feet long. 3. An off-gas arrangement which will eliminate return of ammonia to the dissolver during the Zirflex decladding process. 4. A vessel in which small charges can be dissolved without using extra chemicals. 5. A by-pass routing around the silver reactor during cladding removal.

Space has been reserved near the southeast corner of the 100-N Area for the 122-N Decontamination Facility. Previous correspondence between Burns and Roe, Inc and General Electric bae discussed various facilities which might be needed in the building. The concepts of the decontamination processes are under active development by research groups at Hanford. At present, there are several workable processes known; each one has one or more fairly serious drawbacks.

This is the second of two reports describing the phases of a study of the wear and galling of autoclaved Zircaloy-2 by various fuel element support materials. The first report (1) showed that increasing contact area between the autoclaved Zircaloy-2 support and the autoclaved Zircaloy-2 process tube will not significantly improve the fuel support performance, and that a large flat contact area between the fuel supports and the process tube would be impractical to endeavor to achieve and maintain. It also showed that metals softer than Zircaloy-2 do not scratch the process tube but that loss of these metals by abrasion into the reactor coolant might be a problem.

A coolant line rupture during operation of a high temperature gas cooled graphite moderated reactor would present a serious hazard. The reactor would immediately depressurize and a great deal of air would be introduced into the coolant stream. As the air passed over the graphite moderator a runaway oxidation reaction would probably ensue unless an adequate safety system were available. This investigation was designed to evaluate chlorine as a reactor safeguard to be used to control a runaway reaction. Throughout this study, a small amount of chlorine in an air stream has demonstrated the ability to substantially reduce the oxidation rate of graphite. This has been the case even where the principal oxidizing agent was molecular oxygen or ozone.

Measurements of k∞, f, p, and ∈ have been performed in the PCTR in support of the EGCR Program. The values listed below were obtained for the 21.875-inch cell used in the PCTR measurements. They are for a nonabsorbing (helium or vacuum) atmosphere.

This report summarizes the research and development work carried out during June, July, and August, 1959, for Budget Activity 2790- Separations Development for Non-Production Reactors. The effort on Activity 2790 - Separations Development for Non-Production Reactors. The effort on Activity 2790 will enable Hanford to begin reprocessing in January, 1962, the fuel elements from power reactors which employ depleted or slightly enriched uranium fuels.

This report summarizes experimental results obtained for the General Electric Company under terms of Design, Development and Research Contrast DDR-33. A discussion of the results, the manner in which they were obtained and their probable accuracy are included. Suggested improvements or modifications of properties of this nature be contemplated.

Various methods and procedures for preparing uranium dioxide bodies for metallographic examination and study have been utilized by various investigators. Unfortunately, these methods are not in general satisfactory for use on irradiated uranium dioxide. Since radiation damage studies on irradiated uranium dioxide require use of electron microscopy, and reveal structure by virtue of surface relief. This report covers an investigation of etching methods compatible with radiometallurgy and electron microscopy requirements.

A study of the nuclear safety in the storage and transportation of PRTR fuel elements has been made. This study was based on 7-rod clusters of plutonium-aluminum allow fuel elements containing 1.8 per cent Pu by weight. Each cluster is 7 feet 4 inches in length and contains 270 grams plutonium. Drawings of the "New Fuel Storage Pit" (H-3-11030) have been reviewed for nuclear safety. Nuclear safety criteria for the design of a lead shielded fuel transfer cask as well as criteria for the storage of these fuel elements outside the facilities mentioned in the above drawings have also been reviewed. For water moderated systems, a homogeneous model of plutonium, aluminum, and water was used t evaluate the critical parameters. These results should be conservative. At the conclusion of an experimental program to determine criticality parameters of PU-Al alloys in light water, a theoretical approach will be developed to calculate such criticality parameters.

Water treatment systems for preparing and maintaining high purity water in out-of-reactor or in-reactor test oops are becoming increasingly important. In out0of-reactor experiments the presence of ionic impurities in the water has a marked influence on film formation and corrosion rates. It is therefore , imperative that these impurities be maintained at the lower practical concentration.

Fused uranium dioxide has desirable characteristics for fabricating high density nuclear fuel elements by swaging. Methods of preparing dense uranium dioxide particles being investigated at HAPO include are arc fusion, and sintering and crushing of low density powder. This paper reports the results of exploratory experiments to prepare fused uranium dioxide by induction heating of low density powder in graphite crucibles.

Recently proposals for justifiable additions to the Plutonium Recycle Test Reactor Complex were presented to the Atomic Energy Commission at their request. In addition to a critical reactivity measuring facility in the fuel element storage basin, the following in-reactor loops were proposed: 1. A high pressure, H2O cooled fuel test loop. 2. A rupture loop to investigate fuel element failures. 3. One or more materials testing loops.