In support of the Plutonium Recycle Program at Hanford, the properties of PuO2 are being investigated. This paper reports sintering studies on PuO2 and PuO2-UO2 mixtures and solid solutions; melting studies on PuO2 and UO2; thermal expansion data to 1000 C; and irradiation data on PuO2-UO2 mixtures. The existence of a continuous series of solid solutions formed during sintering has been established for the system UO2-PuO2. A linear relation between lattice parameter and composition exists. Extensive sinterability data on the isomorphous compound UO2 and PuO2 and their intermediate compositions has been obtained. The effect on sintered density of temperature, time, and concentration for both physical additions of PuO2 and additions of UO2-PuO2 solid solutions to UO2 have been studied. Evaluation data are supported by microscopic examination and X-ray diffraction.

The current concepts for reprocessing of non-production reactor fuels at Hanford and other AEC sites were reviewed at the AEC Symposium on "Chemical Processing of Irradiated Fuels from Power, Test and Research Reactors" held at Richland on October 20 and 21, 1959. A report on the symposium will be issued early in 1960 in Bulletin TID-7583. Current planning calls for location of the receiving and storage, mechanical treatment, dissolution, clarification and solution storage facilities at the Uranium Recovery Plant. Dissolver solution is to be piped to the Redox Plant for separation and decontamination of the uranyl and plutonium nitrates. The decontaminated uranium product will be shipped as a uranyl nitrate solution to another AEC site for calcination. No further treatment of the plutonium nitrate is planned in the present project.

For many years effort has been directed toward the development of means for the practical utilization of the heat evolved from the radioactive decay of certain fission and irradiation products. Fission products, in view of their availability in the plentiful, high-level wastes resulting from the processing of irradiated, nuclear reactor fuels have been most intensively studied for applications where their heat of decay might be converted into useful energy such as electricity for the operations of certain devices in place of chemical batteries . In addition other materials having desired radioactive properties may be produced by neutron bombardment of readily available elements.

It is desirable that a reactor exhibit a self-regulating effect. If this were not true any disturbance to the reactor would result in a continual increase in the magnitude of the disturbance and the reactor would be unstable. In this investigation the reactor is considered to have two reactivity feed-backs: metal temperature and water temperature reactivity effects. These two variables through a metal temperature coefficient and water temperature coefficient determine not only the reactor stability but also determine many operational characteristics.

Relatively frequent agitator failures in HAPO Separations Plants have interfered with process continuity, contributed to process difficulties, and resulted in considerable maintenance expense. Predominantly the failures have been because of gear-reduction drive unit break-down or because of metallic fatigue and degeneration of the shaft-paddle assemblies. A simplified, slow-speed, direct drive agitator, previously described in HW-52755, proved to be quite durable and satisfactory during extended testing, operating without incident for over 10,000 hours. Subsequent operation of the agitator in the Redox Plant has been equally smooth. Total operating time (combined test and production use) is now in excess of 21,000 hours. Since the slow speed agitation principle has been adequately demonstrated at Redox and Purex canyon applications. This report describes the development and testing of such a "universal" agitator.

This is the sixth in a series of interim reports describing various phases of the study of fuel element rupture kinetics and mechanisms. Previous reports issued are: No. 1- Experimental Methods and Procedures, HW-61378, No. 2- Coextruded Rod Elements with Pinhole Defects, HW-61379, No. 3 - Mechanism of the Uranium-Water Reaction, HW - 61799, No. 4 Coextruded Tube Elements with Pinhole Defects and Various Annular Spacings, HW- 62348, No. 5- Comparison of In-Reactor and Ex-Reactor Ruptures, HW-62766. This work is being done in cooperation with the Fuel Element Design Operation of the Hanford Laboratories Operation. J. W. Goffard has been particularly helpful in supplying samples and useful discussions of the results.

The current interest in a tube-in-tube type Zircaloy-2 clad UO2 fuel element for use in the power reactors provided the incentive for a study of the dissolution of cladding from an annular space. The objectives of the study were to compare the estimated rate of dissolution in the annuli with rates on fully exposed metal. Because of an interest from the design standpoint, heat balance data from the study are reported.

The importance of maintaining high purity water for in-reactor reactor recirculation facilities is well known. High Purity water reduces corrosion and minimizes radiation to a tolerable level. The Coolant Testing Unit utilizes various resins to maintain the water quality in the in-reactor test facilities. The purposes of this report are: (1) to explain the processes of water conditioning for loop make-up water and special conditioning for loop clean up water; (2) to discuss the utilization and specifications of the resins; (3) to summarize the performance of these resins and the various problems encountered in their uses; (4) to show how some of these problems may be minimized or possibly be eliminated.

A preliminary evaluation of the autoclave corrosion behavior of a series of U-low C alloys and a series of U-low Zr alloys prepared by Fuels Fabrication Development Operation has been made. The corrosion testing was conducted by Coatings and Corrosion Operation by the experimental methods and procedure outlined in HW-61378.

The majority of two-phase flow problems involving equations of state are solved by use of point-wise utilization steam table values. In this manner, problems involving the use of the various flow equations of continuity, momentum and energy are generally forced into iterative solutions. Considerable effort towards the development of an analytical expression for the state equation seems indicated so as to simplify the analysis of two-phase problems, particularly apparent in the analysis of systems undergoing phase transformation as demonstrated by the significant difference between simple theory and experimental critical flow determinations. The assumption of homogeneous, equilibrium mixture is indicated as a first attack upon the problem.

The first series of tests in the KER-REP-1 loop proved that a fission product contaminated loop could be decontaminated to a safe level for contact maintenance. Since a good decontamination process was available, there was much that could be improved about this process. Further testing of this process and several variations of other processes have been scheduled. The evaluation of these processes includes specific decontamination factors, process corrosion, and loop activity reduction factors (loop decontamination factors).

The chromium-nickel-manganese alloys are a group of austenitic stainless steels which were developed during the Korean War to conserve nickel. These alloys are very similar to their corresponding 300 Series grades in mechanical, physical and corrosion properties. A portion of the nickel in the 300 Series grades has been replaced by approximately 2% manganese for each percent of nickel replaced. Two compositions, AISI 201 and AISI 202, are recognized as standard grades. Two other compositions, AISI 204 and AISI 204-L, have been produced in limited quantities to replace AISI 304 and AISI 304-L. Experience with the 200 Series steels indication they are every bit as good as the grades for which they were once alternates. In some shapes, such as rod and sheet, the cost per pound is considerably lower than the corresponding 300 Series grades.

This document describes required laboratory space and lists major equipment items necessary for a routine water quality laboratory in the P. R. T. R. Building. During discussions with R. D. Widrig and V. L. Rooney about the analytical sample program for the Plutonium Recycle Test Reactor, the author was asked to summarize equipment and space needs for a water control laboratory to provide routine analytical coverage on some of the water systems. Based upon 1706-KE-KER experience, some operating personnel may be used to provide analytical coverage on those routine analyses that are needed on around-the-clock basis with a savings of both time and money.

The utilization of gloves wherein heavy element additives have been included is a significant means of reducing exposure to hands and, consequently, increasing allowable working time in operations which require direct contact with low energy isotopes - such as plutonium. The number of such gloves available has been limited considerably by the feasibility of fabrication and the practicality of application. The following study was made on two basic gloves - the first, a heavy zinc-neoprene coated glove and the second, a lead loaded neoprene glove available in two thicknesses. Included in the study was a standard 30 gauge neoprene glove.

On July 31, 1959, an autoclave ruptured while being used for thermal cycling studies of Plutonium Recycle Test Reactor (PRTR) plutonium-aluminum fuel elements. Since stand-in materials were being used in this test, no contamination was involved. This accident could lead to inference of greater hazards associated with PRTR fuel designs than had previously been postulated. An ad hoc technical investigation committee was appointed by the Manager Reactor and Fuels Research and Development, to study the autoclave failure. The committee was charged with developing a sound technical explanation of the accident and/or recommending experimental programs to test hypotheses of the physical and chemical processes leading to the rupture of the autoclave.

Considerable interest has developed in the use of ion-exchange in the nuclear energy field in the last decade. Aside from the obvious use of providing demineralized coolant water for reactors, the projected uses of ion-exchange include the recovery of fission products from aquaeous waste streams and the separation and purification of fissionable materials from spent reactor fuels. The latter process may be incidental to the over-all operation, as is the case with the Purex anion exchange facility, or it may be the prime separation process, as may be the case in the recovery of Pu or U from spent power reactor (PRTR) fuel elements.

The first series tests in the KER-REP-1 loop proved that a fisssion product contaminated loop could be decontaminated to a safe level for contact maintenance. The second series of tests ere scheduled for a more thorough evaluation of these processes includes specific decontamination factors, process corrosion rates, loop activity reduction factors (loop decontamination factors), and any preferential decontamination which may be present.

Design Test Request PR-20 Calandria Characteristics, outlined the need for experimental data concerning the performance of the calandria under transient conditions. Test data was required to confirm that the moderator dump system would drop the level the required 24 inches in less than one second. The original calandria dump chamber design was modified until the criteria was met. This information is recorded in HW-58333, Interim Report, Design Test PR-20, Calandria Characteristics, which lists the drop for the first 24 inches only.

The purpose of this program is to determine the effects of neutron radiation and reactor gaseous atmospheres on the structural integrity of candidate materials for the PRTR gas-cooled loop. An exploratory investigation is being conducted to select a high temperature resistant alloy for the fabrication of tubes and supporting appliances for the PRTR gas-cooled loop. In addition to a low neutron cross section, the material must be able to withstand the operating conditions outlined in Table 1.

The Atomic Energy Commission has assigned the Hanford Atomic Products Operation the responsibility of providing the technology and facilities for the interim reprocessing of slightly enriched uranium fuels discharged from power and propulsion reactors. The fuel from the various reactors vary greatly in physical dimensions and in the composition of the core and cladding. For the purposes of chemical reprocessing, the fuels may be divided into the three main categories of aluminum, Zircaloy or stainless steel clad elements. The fuels may be sub-divided by the nature of the core material; e.g. metallic uranium, uranium dioxide, uranium-molybdenum alloys uranium-aluminum alloys, etc.

For purposes of an earlier consideration of the effects of in-reactor test loops on PRTR operation and program, the design of the high pressure, H20 cooled fuel test loop was assumed to be similar to that for the high pressure, gas cooled loop. Detailed design criteria for the H20 loop have recently been completed so that this assumption is no longer necessary. Therefore, to insure that the effects of all proposed in-reactor loops are fully evaluated with respect to Plutonium Recycle Program objectives, the present study has been carried out. Much of the qualitive discussion in the original analysis is still considered valid. Thus, rather than repeating the entire analysis as it pertains to the H20 loop, only those departures resulting from differences between the assumed design and the scope design are presented.

The Fermi age of thermal neutrons in a lattice containing both water and graphite in some sort of weighted average of the age in water and in graphite independently, with correction for volumes of non-moderating elements or voids. The correct weighting function has been in question during design calculations for the NPR. This paper presents a very simple and direct approach to the problem, resulting in a weighting equation which seems to be theoretically sound. Unfortunately, simple theories cannot be guaranteed to give good results in complicated systems; nevertheless, it appears that the weighting dunction derived here is to be preferred over methods involving empirical relationships which are of doubtful validity in the NPR geometry.

The basic scheme for processing power reactor fuels at Hanford includes the removal of inert endfittings ("hardware") from the active sections of the fuels. Within Hanford Laboratories, research and development studies have been in progress on various types of saws which might be used for hardware cutoff. In the initial phase of the program, high-speed saws were investigated; more recently, studies on low speed saws have been conducted. This report summarizes the high speed saw studies and includes information on abrasive wheels, diamond wheels and metal "friction" blades which cut by actually melting metal ahead of the saw blade. At the completion of the low speed saw testing program currently in progress, basic saw types will be compared and the saw type to be included in the reprocessing complex will be selected.

Zircaloy-2 has a strong tendency to absorb oxygen and nitrogen at elevated temperatures. These gas impurities are extremely harmful, causing brittleness and loss of corrosion resistance. The production of ductile corrosion-resistant welds by present methods required shielding of the weld metal by an inert gas atmosphere or by a vacuum. The alternative to an inert gas atmosphere or a vacuum is reduction of the welding time to a few milliseconds of time to prevent gas absorption.