Search

Traditional confinement practices limit exposure to sunlight and vitamin D synthesis, and vitamin insufficiency occurs even with dietary supplementation. The aim of this study was to determine the effect of limited sun exposure on serum concentration of vitamin D and the expression of vitamin D synthesizing enzymes in the liver and kidney of pigs on a vitamin D sufficient diet. White-pigmented grower pigs (29.7 ± 2.3 kg) fed 15% CP diet ad libitum providing >1,200 IU vitamin D3/kg of feed were exposed to sunlight for 1 h each day at solar noon for 14 d at the spring equinox (March pigs, n = 10) or summer solstice (June pigs, n = 5) and again before slaughter in June (March pigs) and September (June pigs). Blood for the analysis of 25(OH)D was collected before and after sunlight exposure. Traditionally housed pigs served as controls. After initial sun exposure, blood samples were collected from June pigs daily for 5 d and weekly for 8 wk to determine vitamin D3 and 25(OH)D decay, respectively. Kidney and liver samples were collected from the June pigs at slaughter after sun exposure for analysis of messenger RNA expression of vitamin D binding protein and synthesizing/degrading enzymes. Average daily gain (ADG) was not influenced (P > 0.5) by sunlight exposure. June pigs had fewer days on feed, lower (P = 0.003) ADG and were slaughtered at a lighter (P < 0.001) weight. Exposure to sunlight increased (P < 0.001) 25(OH) vitamin D for all pigs. March pigs, obtained from a Midwest producer, had lower (P < 0.001) concentration of 25(OH)D than June pigs born on-farm. Initial sunlight exposure increased serum concentration of 25(OH)D in March pigs by 200% and June pigs by 67%. Serum concentration of vitamin D3 was decreased (P < 0.05) by 72 h with 25(OH)D decreased (P < 0.05) by wk 4 after exposure. Expression of vitamin D binding protein, vitamin D synthesizing CYP2R1, CYP27A1, CYP2D25, or degrading enzyme CYP24A1 were not influenced (P ≥ 0.19) by sunlight exposure. Expression of CYP27B1 was decreased (P = 0.04) in the kidney but tended to be increased (P = 0.06) in the liver after sun exposure. These results suggest limited sun exposure can efficiently increase serum concentration of vitamin D in growing pigs with varying levels of vitamin sufficiency. The lack of major changes in vitamin synthesizing enzymes suggests the 14-d exposure period did not saturate the capacity of slaughter-weight pigs to synthesize vitamin D.

This report provides a collection of annotated bibliographies for documents prepared under the Hanford High-Level Waste Vitrification (Plant) Program. The bibliographies are for documents from Fiscal Year 1983 through Fiscal Year 1995, and include work conducted at or under the direction of the Pacific Northwest National Laboratory. The bibliographies included focus on the technology developed over the specified time period for vitrifying Hanford pretreated high-level waste. The following subject areas are included: General Documentation; Program Documentation; High-Level Waste Characterization; Glass Formulation and Characterization; Feed Preparation; Radioactive Feed Preparation and Glass Properties Testing; Full-Scale Feed Preparation Testing; Equipment Materials Testing; Melter Performance Assessment and Evaluations; Liquid-Fed Ceramic Melter; Cold Crucible Melter; Stirred Melter; High-Temperature Melter; Melter Off-Gas Treatment; Vitrification Waste Treatment; Process, Product Control and Modeling; Analytical; and Canister Closure, Decontamination, and Handling

Studies are being conducted by the Hanford Waste Vitrification Plant (HWVP) Project on ways to increase the waste processing capacity within the current Vitrification Building structural design. The Phase 1 study on remote systems concepts identification and extent of capacity increase was completed. The study concluded that the HWVP capacity could be increased to four times the current capacity with minor design adjustments to the fixed facility design, and the required design changes would not impact the current footprint of the vitrification building. A further increase in production capacity may be achievable but would require some technology development, verification testing, and a more systematic and extensive engineering evaluation. The primary changes included a single advance melter with a higher capacity, new evaporative feed tank, offgas quench collection tank, ejector venturi scrubbers, and additional inner canister closure station,a smear test station, a new close- coupled analytical facility, waste hold capacity of 400,000 gallon, the ability to concentrate out-of-plant HWVP feed to 90 g/L waste oxide concentration, and limited changes to the current base slab construction package.

The Hanford Waste Vitrification Plant (HWVP) is being designed for the Department of Energy to immobilize pretreated radioactive high-level waste and transuranic waste as glass for permanent disposal. Laboratory studies were conducted to characterize HWVP slurry chemistry during selected processing steps, using pretreated Neutralized Current Acid Waste (NCAW) simulant. Laboratory tests were designed to provide bases for determining the potential for hazardous gas generation, making chemical adjustments for glass redox control, and assessing the potential for rapid exothermic reactions of dried NCAW slurry. Offgas generation rates and the total moles of gas released as a function of selected pretreated NCAW components and process variables were measured. An emphasis was placed on identifying conditions that initiate significant H{sub 2} generation. Glass redox measurements, using Fe{sup +2}/{Sigma}Fe as an indicator of the glass oxidation state, were made to develop guidelines for HCOOH addition. Thermal analyses of dried NCAW simulant were conducted to assess the potential of a rapid uncontrollable exothermic reaction in the chemical processing cell tanks.

A key element of the Hanford waste management strategy is the construction of a new facility, the Hanford Waste Vitrification Plant (HWVP), to vitrify existing and future liquid high-level waste produced by defense activities at the Hanford Site. The HWVP mission is to vitrify pretreated waste in borosilicate glass, cast the glass into stainless steel canisters, and store the canisters at the Hanford Site until they are shipped to a federal geological repository. The HWVP Technical Manual (Manual) documents the technical bases of the current HWVP process and provides a physical description of the related equipment and the plant. The immediate purpose of the document is to provide the technical bases for preparation of project baseline documents that will be used to direct the Title 1 and Title 2 design by the A/E, Fluor. The content of the Manual is organized in the following manner. Chapter 1.0 contains the background and context within which the HWVP was designed. Chapter 2.0 describes the site, plant, equipment and supporting services and provides the context for application of the process information in the Manual. Chapter 3.0 provides plant feed and product requirements, which are primary process bases for plant operation. Chapter 4.0 summarizes the technology for each plant process. Chapter 5.0 describes the engineering principles for designing major types of HWVP equipment. Chapter 6.0 describes the general safety aspects of the plant and process to assist in safe and prudent facility operation. Chapter 7.0 includes a description of the waste form qualification program and data. Chapter 8.0 indicates the current status of quality assurance requirements for the Manual. The Appendices provide data that are too extensive to be placed in the main text, such as extensive tables and sets of figures. The Manual is a revision of the 1987 version.

Numerous studies (Section 8) have,addressed the Theological properties of simulated process slurries at the Savannah River Laboratory for the Defense Waste Processing Facility and at Pacific Northwest Laboratory`(PNL) for the Hanford Waste Vitrification Plant (HWVP). These studies were reviewed to summarize existing data applicable to HWVP design. The reviewers determined that the existing data provide important information on the effects of feed variability, solids loading, temperature, formating, pH, and scale-up. However, these data cannot serve as a basis for fundamental slurry transport calculations because data are not reported in sufficient detail over a range of shear rates and in appropriate terms to be sufficient for transport calculations.

Extensive surface pressure measurements were obtained on a hypersonic vehicle configuration at Mach 8 for the purpose of computational fluid dynamics code validation. Experiments were conducted in the Sandia National Laboratories hypersonic wind tunnel. All measurements were made for laminar flow conditions at a Reynolds number (based on model length) of 1.81 x 10{sup 6} and perfect gas conditions. The basic vehicle configuration is a spherically blunted, 10{degree} half- angle cone, with a slice parallel to the axis of the vehicle. To the aft portion of the slice could be attached flaps of varying angle; 10, 20, and 30{degree}. Surface pressure measurements were obtained for angles of attack from -10 to +18{degree}, for various roll angles, at 96 locations on the body surface. All three deflected flap angles produced separated flow on the sliced portion of the body in front of the flap. Because of the three-dimensional expansion over the slice, the separated flow on the slice and flap was also highly three- dimensional. The results of the present experiment provide extensive surface pressure measurements for the validation of computational fluid dynamics codes for separated flow caused by an embedded shock wave.

The noble metals Pd, Rh, and Ru that are present in the Hanford high-level waste will be processed into a melter feed for vitrification and permanent disposal. The treatment of waste slurry with HCOOH, a step in producing a melter feed, results in the production of H{sub 2} and NH{sub 3} due to the catalytic activity of the noble metals. The presence of H{sub 2} and NH{sub 3} could lead to hazardous conditions in a treatment facility. This study determined the relationship between noble metals concentration and H{sub 2} and NH{sub 3} production for application in future pilot-scale studies and prediction of catalytic activity for a waste with known noble metals concentration. Hydrogen production increased as noble metals concentration increased until a saturation level was reached. Ammonia production increased with noble metal concentration. Due to the limited number of tests, these relationships require confirmation.

The Hanford Waste Vitrification Plant (HWVP) is being designed for the Department of Energy to immobilize high-level and transuranic wastes as glass for permanent disposal. Pacific Northwest Laboratory is supporting the HWVP design activities by conducting laboratory-scale studies using a HWVP simulated waste slurry. Conditions which affect the slurry processing chemistry were evaluated in terms of offgas composition and peak generation rate and changes in slurry composition. A standard offgas profile defined in terms of three reaction phases, decomposition of H2CO3, destruction of NO2-1, and production of H2 and NH3 was used as a baseline against v/hich changes were evaluated. The test variables include nitrite concentration, acid neutralization capacity, temperature, and formic acid addition rate. Results to date indicate that pH is an important parameter influencing the N2O/NOx generation ratio; nitrite can both inhibit and activate rhodium as a catalyst for formic acid decomposition to CO2 and H2; and a separate reduced metal phase forms in the reducing environment. These data are being compiled to provide a basis for predicting the HWVP feed processing chemistry as a function of feed composition and operation variables, recommending criteria for chemical adjustments, and providing guidelines with respect to important control parameters to consider during routine and upset plant operation.

The design of a slurry-fed electric gas melter and an examination of the performance and condition of the construction materials were completed. The joule-heated, ceramic-lined melter was constructed to test the applicability of materials and processes for high-level waste vitrification. The developmental Liquid-Fed Ceramic Melter (LFCM) was operated for three years with simulated high-level waste and was subjected to conditions more severe than those expected for a nuclear waste vitrification plant.

This document describes a conceptual high-level waste immobilization facility. The facility would have the capability to calcine and then vitrify high-level liquid waste (HLLW). The vitrification would be accomplished in a canister which is seal-welded, checked for integrity, and decontaminated for movement to storage. Included in the facility would be the capability to repair faulty canister-lid seal welds, overpack failed canisters, and treat the process off-gas and cell ventilation air prior to release to the fuel reprocessing plant (FRP) atmospheric protection system (APS). The nuclear waste vitrification facility (NWVF) would be an integral part of the FRP structure. The operations of the facilities would be centered in the waste vitrification cell (WVC) which performs most of the facility functions. The cell is a reinforced concrete hot cell, lined with stainless steel. Most operation and maintenance activities would be performed remotely using a crane equipped with an impact wrench or yoke. The major facility equipment includes a feed tank, spray calciner, two melters, weld-inspection stations, canister storage rack, and a canister decontamination cubicle. Installation and removal of equipment in the cell would be done through shielding doors. The air lock system of the canister decontamination cubicle would permit placement and removalmore » of the canister. Activities in the cell may be observed through four shielding glass windows and/or up to three periscopes. The operating, service, and pipe galleries which house operating personnel and equipment necessary for cell operations are located adjacent to the cell.« less

A study was performed to assess radionuclide leak-detection systems for use in locating a capsule leaking strontium-90 or cesium-137 into a water-filled pool. Each storage pool contains about 35,000 L of water and up to 715 capsules, each of which contains up to 150 kCi strontium-90 or 80 kCi cesium-137. Potential systems assessed included instrumental chemical analyses, radionuclide detection, visual examination, and other nondestructive nuclear-fuel examination techniques. Factors considered in the assessment include: cost, simplicity of maintenance and operation, technology availability, reliability, remote operation, sensitivity, and ability to locate an individual leaking capsule in its storage location. The study concluded that an adaption of the spent nuclear-fuel examination technique of wet sipping be considered for adaption. In the suggested approoch, samples would be taken continuously from pool water adjacent to the capsule(s) being examined for remote radiation detection. In-place capsule isolation and subsequent water sampling would confirm that a capsule was leaking radionuclides. Additional studies are needed before implementing this option. Two other techniques that show promise are ultrasonic testing and eddy-current testing.

This technical manual summarizes process and equipment technology developed at Pacific Northwest Laboratory over the last 20 years for vitrification of high-level liquid waste by the Spray Calciner/In-Can Melter process. Pacific Northwest Laboratory experience includes process development and demonstration in laboratory-, pilot-, and full-scale equipment using nonradioactive synthetic wastes. Also, laboratory- and pilot-scale process demonstrations have been conducted using actual high-level radioactive wastes. In the course of process development, more than 26 tonnes of borosilicate glass have been produced in 75 canisters. Four of these canisters contained radioactive waste glass. The associated process and glass chemistry is discussed. Technology areas described include calciner feed treatment and techniques, calcination, vitrification, off-gas treatment, glass containment (the canister), and waste glass chemistry. Areas of optimization and site-specific development that would be needed to adapt this base technology for specific plant application are indicated. A conceptual Spray Calciner/In-Can Melter system design and analyses are provided in the manual to assist prospective users in evaluating the process for plant application, to provide equipment design information, and to supply information for safety analyses and environmental reports. The base (generic) technology for the Spray Calciner/In-Can Melter process has been developed to a point at which it ismore » ready for plant application.« less

The striated rootlets of different protists are extremely diverse and, on the basis of structural organization, can be assigned to no fewer than four major types. In light of this extreme variation in fine-structure is it reasonable to expect that all striated rootlets may share common protein species? Using the flagellar rootlet of Naegleria gruberi strain NB-1 as reference, we compared rootlet size, structure, and protein composition to another Naegleria strain, another amoebo-flagellate, Tetramitus rostratus, and to the ciliate Tetrahymena pyriformis. Although differing in size and distribution in the cells, the rootlets of all three amoebo-flagellates appeared very similar in structure, periodicity, and in the presence of a common 170 000 Dalton subunit. Kinetodesmal fibres of Tetrahymena differed markedly in detailed fine-structure, in periodicity, and in the apparent absence of the 170 000 Dalton subunit as tested either by SDS gel electrophoresis or by indirect immunofluorescence staining using a specific antiserum directed against the NB-1 major rootlet protein. Consideration of literature describing striated rootlet structure in a wide variety of ciliated and flagellated cells led to the speculation that striated rootlets arose subsequent to primitive flagella and likely evolved along two major pathways: a narrow-period rootlet similar to those discussed above, which developed from the microtubule rootlets of algal flagellates, and a wide-band, contractile rootlet which originated from the primitive interbasal body connector prominent in both algal and protozoan species.

In hydrothermal environment tests, three simulated high-level waste (HLW) glasses, supercalcine, and SYNROC exhibit similar leaching behavior. Releases from the glasses are lowest at temperatures below 250/sup 0/C (the expected repository temperature range). Corrosion tests of candidate metallic-container materials in 250/sup 0/C Hanford ground water are under way and a group of polymers that shows good resistance to 200/sup 0/C water in autoclave tests is undergoing gamma irradiation. Methods of reducing melt-foaming in ceramic melters were investigated. Inclusion of monoxides of iron, nickel and manganese in the calcine significantly improved melt quality and reduced foaming. The addition of cornstarch to the melt, which inhibits foaming in laboratory studies, continues to be evaluated. A successful pilot-scale test of the Spray Calciner/In-Can Melter process was done using simulated waste representing the combined contents of the neutralized and Thorex waste tanks at the Western New York Nuclear Service Center. Flexibility of the process for handling high-sodium waste was demonstrated.

Federal regulations require that high-level liquid waste (HLLW) be converted to a solid for custody in a Federal repository. The Spray Solidification/In-Can Melting process has been developed and is being demonstrated for commercial application. The bases used are similar to those of the NFS plant and to anticipated regulations for waste canister receipt at a Federal repository. The reference NFS flowsheet combines plant HA Column Wastes, Low-Level Wastes, and various HLLW process recycle streams to produce a borosilicate glass. After the canister is filled and sealed, the lid weld will be inspected and decontaminated. Equipment and instrumentation for feed supply to the calciner, calcination, melting, welding, weld inspection, canister decontamination, and in-cell canister storage are being designed and demonstrated. Preliminary facility layouts, equipment design data, and instrumentation needs are provided for major process equipment systems. Additional demonstration work is being performed to verify and complete the plant scale equipment design, including full-scale nonradioactive equipment testing, nonradioactive facility mockup for equipment remote operation and maintenance demonstration, and pilot plant production of waste glass from commercial fuel HLLW. The technology for spray calcination and in-can melting is ready for commercial application. Required additional work is described. A preliminary evaluation is made ofmore » materials that may be released from the process from normal and abnormal operations in the facility. 34 figures, 20 tables. (DLC)« less