Thermal reactivity of mixtures of VDDT lubricant and simulated Hanford Tank 241-SY-101 waste

To predict whether the Polywater G lubricant residue remaining in the velocity, density, and temperature tree (VDTT) and the waste in Tank 241-SY-101 (101SY) will be chemically compatible with wastes in 101SY when two VDTTs are removed from 101SY, the Pacific Northwest National Laboratory measured the thermal reaction sensitivity of the lubricant residue. This residue is a simulated 101SY waste containing the organic surrogate trisodium hydroxyethyl-ethylenediaminetriacetate (Na{sub 3}HEDTA) and two simulated potential waste and lubricant residue mixtures containing 10 and 90 percent lubricant residue. These studies using accelerating rate calorimetry found that the residue did not react at a rate exceeding 0.1 J/min/g mixture up to 190 degrees C with simulated 101SY waste containing Na{sub 3}HEDTA as the organic surrogate. Also, the dried lubricant residue did not decompose exothermically at a rate exceeding 0.1 J/min/g. Using guidelines used by the chemical industry, these results indicate that the lubricant residue should not react as a significant rate with the waste in 101SY when added to the waste at 60 degrees C or when the mixture cools to the waste`s temperature of 48 degrees C

Power Histories for Fuel Codes

Computations of power history effects on the pre-loss-of-coolant accident (LOCA) conditions of generic pressurized water reactor (PWR) and boiling water reactor (BWR) fuel rods were performed at Pacific Northwest Laboratory using the U.S. Nuclear Regulatory Commission (NRC) code FRAPCON-2. Comparisons were made between cases where the fuel operated at a high ( 11 LOCA-limited") power throughout life (20,000 MWd/MTU) and those where the fuel was at a lower power for most of its burnup and ramped to the high power at 10,000 or 20,000 MWd/MTU burnup. The PWR rod was calculated to have more cladding creepdown during the lower power cases, which resulted in slightly lower centerline temperatures (as much as 100{degrees}C). This result was insensitive to the method used to increase the power during the ramps (i.e., by increasing the average rod power or by changing the peak-to-average (P/A} ratio of the axial power shape). The calculations also indicate that the highest fuel centerline temperatures were reached at startup. The BWR rod, however, demonstrated a substantial dependence on the power history. In this case, the constant high-power rod released considerably more fission gas than the lower power cases (21% versus 0.4%), which resulted in temperature differences of up to 350°C. The hiqhest temperature was reached at end-of-life (EOL) in the constant high-power case

A Unique Concept for Liquid Level and Void Fraction Detection in Severe Fuel Damage Tests

This report describes a direct-contacting liquid level and void fraction detection system that is being developed by Pacific Northwest Laboratory. The measurement technique could be used in the severe fuel damage tests that will be conducted at the Power Burst Facility, Idaho Falls, Idaho, and at the ESSOR reactor, Ispra, Italy. The detection system could also be retrofitted for commercial operating reactors to provide definitive thermal-hydraulic information. The technique can provide unambiguous, real-time data on liquid level and void fraction during normal reactor operation as well as during shutdown and accident conditions

Assessment of Cosmic Background Attenuation at Building 3425 (Underground Laboratory)

Specifications for the Underground Facility (building 3425) in the Radiation Detection and Nuclear Sciences complex presently under construction at Pacific Northwest National Laboratory mandate a 30 meters water equivalent shielding for cosmic background attenuation at the 30-foot underground depth of the laboratory. A set thickness of a specified fill material was determined; however a smaller thickness of a higher density material was used for the earthen bunker. Questions arose as to whether this altered configuration met the required shielding specifications. A series of measurements were made to address this concern using a 4”x4”x16” NaI(Tl) detector (Scionix Holland, 3.5N-E2-X). Cosmic ray data were taken at the surface, and at several locations within the underground facility in order to obtain an experimental value for the attenuation of the cosmic radiation. This experimental result was compared with the contracted attenuation

User's guide for GAPCON-THERMAL-2: A computer program for calculating the thermal behavior of an oxide fuel rod

This report is being published as a user's manual for GAPCON-THERMAL-2 and provides a general description of the code and instructions for its use. The GAPCON-THERMAL-2 code was developed for the Regulatory Staff, NRC, to use as a tool in estimating fuel-cladding gap conductances and fuel stored energy and represents a modification of the GAPCON-THERMAL-1 code. The goal of the modifications was to reduce uncertainties associated with calculating power history and burnup effects and yet retain a relatively flexible and fast running code for parametric studies. 15 references (auth

A portable neutron coincidence counter

Pacific Northwest National Laboratory has designed and constructed a prototype portable neutron coincidence counter intended for use in a variety of applications, such as the verification and inspection of weapons components, safety measurements for novel and challenging situations, portable portal deployment to prevent the transportation of fissile materials, uranium enrichment measurements in hard-to-reach locations, waste assays for objects that cannot be measured by existing measurement systems, and decontamination and decommissioning. The counting system weighs less than 40 kg and is composed of parts each weighing no more than 5 kg. In addition, the counter`s design is sufficiently flexible to allow rapid, reliable assembly around containers of nearly arbitrary size and shape. The counter is able to discern the presence of 1 kg of weapons-grade plutonium within an ALR-8 (30-gal drum) in roughly 100 seconds and 10 g in roughly 1000 seconds. The counter`s electronics are also designed for maximum adaptability, allowing operation under a wide variety of circumstances, including exposure to gamma-ray fields of 1 R/h. This report provides a detailed review of the design and construction process. Finally, preliminary experimental measurements that confirm the performance capabilities of this counter are discussed. 6 refs., 18 figs., 3 tabs

Review of the algal biology program within the National Alliance for Advanced Biofuels and Bioproducts

In 2010, when the National Alliance for Advanced Biofuels and Bioproducts (NAABB) consortium began, little was known about the molecular basis of algal biomass or oil production. Very few algal genome sequences were available and efforts to identify the best-producing wild species through bioprospecting approaches had largely stalled after the U.S. Department of Energy's Aquatic Species Program. This lack of knowledge included how reduced carbon was partitioned into storage products like triglycerides or starch and the role played by metabolite remodeling in the accumulation of energy-dense storage products. Furthermore, genetic transformation and metabolic engineering approaches to improve algal biomass and oil yields were in their infancy. Genome sequencing and transcriptional profiling were becoming less expensive, however; and the tools to annotate gene expression profiles under various growth and engineered conditions were just starting to be developed for algae. It was in this context that an integrated algal biology program was introduced in the NAABB to address the greatest constraints limiting algal biomass yield. This review describes the NAABB algal biology program, including hypotheses, research objectives, and strategies to move algal biology research into the twenty-first century and to realize the greatest potential of algae biomass systems to produce biofuels