Multi-Input, Multi-Harmonic Nonlinear Phase Resonance Simulations with Harmonic Balance.
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This presentation was given at the ASTM [Virtual] Workshop on Decarbonization: A Gap Analysis of LCA Standards for Industry on October 10, 2023. It discusses concerns about available life cycle data due to a lack of standards and shows how NETL has approached data development for two key areas that satisfy these concerns: electricity and natural gas.
EnergySolutions and its team partners, NAC International, Exelon Nuclear Partners, Talisman International, TerranearPMC, Booz Allen Hamilton and Sargent and Lundy, have carried out a study to develop concepts for a Consolidated Storage Facility (CSF) for the USA's stocks of commercial Used Nuclear Fuel (UNF), and the packaging and transport provisions required to move the UNF to the CSF. The UNF is currently stored at all 65 operating nuclear reactor sites in the US, and at 10 shutdown sites. The study was funded by the US Department of Energy and followed the recommendations of the Blue Ribbon Commission on America's Nuclear Future (BRC), one of which was that the US should make prompt efforts to develop one or more consolidated storage facilities for commercial UNF. The study showed that viable schemes can be devised to move all UNF and store it at a CSF, but that a range of schemes is required to accommodate the present widely varying UNF storage arrangements. Although most UNF that is currently stored at operating reactor sites is in water-filled pools, a significant amount is now dry stored in concrete casks. At the shutdown sites, the UNF is dry stored at all but two of the ten sites. Various types of UNF dry storage configurations are used at the operating sites and shutdown sites that include vertical storage casks that are also licensed for transportation, vertical casks that are licensed for storage only, and horizontally orientated storage modules. The shutdown sites have limited to nonexistent UNF handling infrastructure and several no longer have railroad connections, complicating UNF handling and transport off the site. However four methods were identified that will satisfactorily retrieve the UNF canisters within the storage casks and transport them to the CSF. The study showed that all of the issues associated with the transportation and storage of UNF from all sites in the US can be accommodated by adopting a staged approach to the construction of the CSF. Stage 1 requires only a cask storage pad and railroad interface to be constructed, and the CSF can then receive the UNF that is in transportable storage casks. Stage 2 adds a canister handling facility, a storage cask fabrication facility and an expanded storage pad, and enables the receipt of all canistered UNF from both operating and shutdown sites. Stage 3 provides a repackaging facility with a water-filled pool that provides flexibility for a range of repackaging scenarios. This includes receiving and repackaging 'bare' UNF into suitable canisters that can be placed into interim storage at the CSF, and enables UNF that is being received, or already in storage onsite, to be repackaged into canisters that are suitable for disposal at a geologic repository. The study used the 'Total System Model' (TSM) to analyze a range of CSF capacities and operating scenarios with differing parameters covering UNF pickup orders, one or more CSF sites, CSF start dates, CSF receipt rates and geologic repository start dates. The TSM was originally developed to model movement of UNF to the Yucca Mountain repository and was modified for this study to enable the CSF to become the 'gateway' to a future geologic repository. The TSM analysis enabled costs to be estimated for each scenario and showed how these are influenced by each of the parameters. This information will provide essential underpinning for a future Conceptual Design preparation. (authors)
The CEA has developed many compact characterization tools to follow sensitive operations in a nuclear environment. Usually, these devices are made to carry out radiological inventories, to prepare nuclear interventions or to supervise some special operations. These in situ measurement techniques mainly take place at different stages of clean-up operations and decommissioning projects, but they are also in use to supervise sensitive operations when the nuclear plant is still operating. In addition to this, such tools are often associated with robots to access very highly radioactive areas, and thus can be used in accident situations. Last but not least, the radiological data collected can be entered in 3D calculation codes used to simulate the doses absorbed by workers in real time during operations in a nuclear environment. Faced with these ever-greater needs, nuclear measurement instrumentation always has to involve on-going improvement processes. Firstly, this paper will describe the latest developments and results obtained in both gamma and alpha imaging techniques. The gamma camera has been used by the CEA since the 1990's and several changes have made this device more sensitive, more compact and more competitive for nuclear plant operations. It is used to quickly identify hot spots, locating irradiating sources from 50 keV to 1500 keV. Several examples from a wide field of applications will be presented, together with the very latest developments. The alpha camera is a new camera used to see invisible alpha contamination on several kinds of surfaces. The latest results obtained allow real time supervision of a glove box cleaning operation (for {sup 241}Am contamination). The detection principle as well as the main trials and results obtained will be presented. Secondly, this paper will focus on in situ gamma spectrometry methods developed by the CEA with compact gamma spectrometry probes (CdZnTe, LaBr{sub 3}, NaI, etc.). The radiological data collected is used to quantify the activity of hot spots and can also then be entered in 3D models of nuclear plants to simulate intervention scenarios. Recent developments and results will be presented regarding this. Finally, thanks to a large amount of feedback, the interest of using complementary measurements will be discussed. In fact, the recent use of 3D simulation codes requires very accurate knowledge of nuclear plant radiological data. The use of coupled devices such as imaging devices, (gamma and alpha cameras), gamma spectrometry, dose rate mapping, collimated / un-collimated measurements and many other physical values gives an approach to the radiological knowledge of a process or plant with the lowest possible uncertainty. In line with this, the paper will conclude with the future developments and trials that could be assessed in that field of application. (authors)
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One example special case for Final Status Surveys (FSSs) occurs at Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA) sites at which the radioactive materials are from the processing of uranium or thorium ores for their source material content. At these sites, EPA's Health and Environmental Protection Standards for Uranium and Thorium Mill Tailings, in 40 CFR 192, are applicable. Also, 40 CFR 192 may be invoked at non-UMTRCA sites through the CERCLA as an Applicable or Relevant and Appropriate Requirement (ARAR) due to the presence of radium (Ra)-226 or Ra-228, even though the source of residual radioactive material was not a uranium or thorium mill tailings facility. However, the regulatory requirements in these standards infringe on some of the recommendations in the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM). Specifically, the soil cleanup standards for Ra-226 or Ra-228 are specified as averages over an area of 100 square meters (m{sup 2}). Note that in the 40 CFR 192 rulemaking, an averaging area of 100 m{sup 2} was used as a reasonable footprint for a home. One goal of the 40 CFR 192 standards was to protect future homes from indoor radon, and the specified averaging area was a component implemented for the protection of health. In addition, 40 CFR 192 is silent regarding elevated measurement criteria (EMC)-type requirements for smaller areas of elevated radioactive material within the 100-m{sup 2} footprint. At UMTRCA sites and CERCLA sites where UMTRCA is an ARAR, the following approach for FSSs is acceptable: - Survey units (SUs) may be classified, as appropriate, and survey activities may be adjusted accordingly for Class 1, Class 2, or Class 3 SUs. - Class 1 soil SUs should provide for evaluation of portions that are no greater than 100 m{sup 2} in size, consistent with the 40 CFR 192 standards. - Class 2 and 3 soil SUs are not expected to exceed the 40 CFR 192 soil cleanup standard, so they do not require evaluation of portions that are no greater than 100 m{sup 2} in size. - Compliance with 40 CFR 192 can be demonstrated through analysis of soil samples or composite soil samples from each SU, in conjunction with gamma radiation scanning or in situ gamma radiation measurements of each SU. When appropriate, these gamma radiation scans or in situ measurements correlated to soil sampling may be used in place of soil sampling. - By demonstrating that the average over 100 m{sup 2} meets the 40 CFR 192 soil cleanup standard, the EMC criteria for small elevated areas of activity are not required for the purposes of MARSSIM, but may be developed. These minor modifications to the standard MARSSIM radiological survey approach are acceptable for UMTRCA sites or CERCLA sites where UMTRCA is an ARAR. (authors)
Previous work focused on the use of automated variance reduction parameters for use in a fixed source reactor shielding problem to solve for ex-core particle transport results. The current work assesses that strategy in light of a fully-coupled Monte Carlo problem run as a critical system with parallel processing and the use of moderate variance reduction parameters set manually. The results from the two strategies compare well. Also, results are compared between the MCNP, Virtual Environment for Reactor Applications (VERA) and Shift computer codes. Shift and VERA deliver similar results and compare well to MCNP. (authors)
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Gypsum has been used for thousands of years in building and construction applications, starting with the pyramids in ancient Egypt, to “Plaster of Paris” in the midcenturies, and to the now-ubiquitous drywall in modern-day houses. Production of gypsum drywall boards takes several steps with high energy and water consumption. The current state of the art in industry is a process that begins by mining gypsum and reducing its particle size by milling. These gypsum particles undergo calcination to convert the gypsum (calcium sulfate dihydrate) into stucco (calcium sulfate hemihydrate). The stucco is mixed with additives and enough water to form a slurry that can be poured onto a conveyor belt and molded into the desired geometry. The stucco reacts with the water, converting back into gypsum. The remaining water is then dried from the board to form the final product. While only ~20 wt. % of water is needed for the conversion of stucco to gypsum, significant excess water is needed to ensure sufficient fluidity of the slurry for processibility. This is due to the low quality of the stucco particles produced in high throughput calcination units, which disintegrate upon mixing with water, thereby reducing the fluidity and processability of the slurry. This project aims to produce high-quality stucco particles by dielectric calcination. In doing so, particle integrity can be maintained through the slurry formulation step, and particle size distribution of the stucco can be adjusted to increase fluidity with less excess water. With less water remaining unreacted in the board, significant energy can be saved in drying the product. The project aims to 1) develop a dielectric calcination method to TRL 3, 2) determine optimal and practical particle size distributions to minimize excess water in the slurry, and 3) reduce the energy consumption of the drying process.
The Advanced Scale Up Reactor Experiment (ASURE) facility at NETL is being designed to be a fuel-flexible multi-purpose reactor that can be used for pyrolysis/gasification or evaluation of other high pressure “circulating fluidized bed” (CFB) chemical processes. The initial system design calculations for pyrolysis/gasification are presented in this work showing the expected performance of the ASURE facility when used as a biomass conversion reactor. Several other areas of application include gasification of any carbonaceous fuel including biomass, coal, plastics, and other waste materials. The reactor can therefore be used to produce SYNGAS of various compositions and hydrogen as well as other high value chemicals resulting from a typical tuned gasification process. This paper discusses an ASPEN model of the facility, focusing on the riser of the CFB reactor and the solids recirculation loop. The ASPEN model divides the riser into two sections. A bottom section which receives ash, char and sand which have been recirculated from a return loop. In this section an inert fluidization gas, (N2 or CO2), is introduced which acts as the primary mover of the solids through the system. The bottom section is equipped with a restricted air feed so that the recirculated char can be partially oxidized. This oxidation process along with the inventory of recirculating sand are used to effectively control the temperature in the following two chemical conversion sections of the reactor which are the pyrolysis zone followed by a tar cracking zone. Fresh fuel is added to the pyrolysis zone and undergoes drying and devolatilization. The products ash, char, volatile matter, and water vapor exit the pyrolysis zone and enter the reaction block for tar cracking. Steam and CO2 gasification reactions will be incorporated into the tar cracking zone, however at the design operating temperature, conversion from these reactions is expected to be essentially zero. The unit when completed in 2026 will test mixtures of biomass, plastics, and waste coal. This paper presents the basic ASPEN engineering design model for this project and provides preliminary sensitivity studies to determine how the various parts of the reactor will perform.
This document represents a contribution of the United States early career collider physics community to the 2025--2026 update to the European Strategy for Particle Physics. Preferences with regard to different future collider options and R&D priorities were assessed via a survey. The early career community was defined as anyone who is a graduate student, postdoctoral researcher, untenured faculty member, or research scientist under 40 years of age. In total, 105 participants responded to the survey between February and March 10th, 2025. Questions were formulated primarily to gauge the enthusiasm and preferences for different collider options in line with the recommendations of the United States' P5 report, relevant to the European Strategy Update.