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Schneider, Erich

Publications and source records attributed to Schneider, Erich.

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Advanced Fuel Cycle Cost Basis Report: Supporting Document 7 Presentation: Du and RU Disposal Costs [Slides]

Worldwide DU and RU in various chemical forms are some of the largest legacy products of the nuclear industry (defense & power) in both mass and volume. Chemical forms include U metal or alloy, UF6, UO2, UO3, U3O8, and UF4. Most of this material is now in above ground storage. Due to chemical stability and low water solubility oxides are the preferred form for safe storage and ultimate disposal. Long term U disposal in large amounts presents more of a potential radioactivity problem than its conversion and temporary storage. Now a near term problem with freshly-mined uranium ore, radon emanation will eventually be a long-term problem for both DU and RU dispositioned in large quantities at a specific location.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2017

Investigations into the Reusability of Amidoxime-Based Polymeric Adsorbents for Seawater Uranium Extraction

The ability to re-use amidoxime-based polymeric adsorbents is a critical component in reducing the overall cost of the technology to extract uranium from seawater. This report describes an evaluation of adsorbent reusability in multiple re-use (adsorption/stripping) cycles in real seawater exposures with potassium bicarbonate (KHCO3) elution using several amidoxime-based polymeric adsorbents. The KHCO3 elution technique achieved ~100% recovery of uranium adsorption capacity in the first re-use. Subsequent re-uses showed significant drops in adsorption capacity. After the 4th re-use with the ORNL AI8 adsorbent, the 56-day adsorption capacity dropped to 28% of its original capacity. FTIR spectra revealed that there was a conversion of the amidoxime ligands to carboxylate groups during extended seawater exposure, becoming more significant with longer the exposure time. Ca and Mg adsorption capacities also increased with each re-use cycle supporting the hypothesis that long term exposure resulted in converting amidoxime to carboxylate, enhancing the adsorption of Ca and Mg. Shorter seawater exposure (adsorption/stripping) cycles (28 vs. 42 days) had higher adsorption capacities after re-use, but the shorter exposure cycle time did not produce an overall better performance in terms of cumulative exposure time. Recovery of uranium capacity in re-uses may also vary across different adsorbent formulations. Through multiple re-use the adsorbent AI8 can harvest 10 g uranium/kg adsorbent in ~140 days, using a 28-day adsorption/stripping cycle, a performance much better than would be achieved with a single use of the adsorbent through very long-term exposure (saturation capacity = 7.4 g U/kg adsorbent). A time dependent seawater exposure model to evaluate the cost associated with reusing amidoxime-based adsorbents in real seawater exposures was developed. The cost to extract uranium from seawater ranged from $610-830/kg U was predicted. Model simulation suggests that a short seawater exposure cycle (< 15 days) is the optimal deployment period for lower uranium production cost in seawater uranium mining.

Kuo, Li-Jung↗
DOE OSTI2017

Developing the User Experience for a Next Generation Nuclear Fuel Cycle Simulator (NGFCS)

This project made substantial progress on its original aim for providing a modern user experience for nuclear fuel cycle analysis while also creating a robust and functional next- generation fuel cycle simulator. The Cyclus kernel experienced a dramatic clari cation of its interfaces and data model, becoming a full- edged agent-based framework, with strong support for third party developers of novel archetypes. The most important contribution of this project to the the development of Cyclus was the introduction of tools to facilitate archetype development. These include automated code generation of routine archetype components, metadata annotations to provide re ection and rich description of each data member's purpose, and mechanisms for input validation and output of complex data. A comprehensive social science investigation of decision makers' interests in nuclear fuel cycles, and speci cally their interests in nuclear fuel cycle simulators (NFCSs) as tools for understanding nuclear fuel cycle options, was conducted. This included document review and analysis, stakeholder interviews, and a survey of decision makers. This information was used to study the role of visualization formats and features in communicating information about nuclear fuel cycles. A exible and user-friendly tool was developed for building Cyclus analysis models, featuring a drag-and-drop interface and automatic input form generation for novel archetypes. Cycic allows users to design fuel cycles from arbitrary collections of facilities for the rst time, with mechanisms that contribute to consistency within that fuel cycle. Interacting with some of the metadata capabilities introduced in the above-mentioned tools to support archetype development, Cycic also automates the generation of user input forms for novel archetypes with little to no special knowledge required by the archetype developers. Translation of the fundamental metrics of Cyclus into more interesting quantities is accomplished in the Cymetric python package. This package is speci cally designed to support the introduction of new metrics by building upon existing metrics. This concept allows for multiple dependencies and encourages building complex metrics out of incremental transformations to those prior metrics. New archetype developers can contribute their own archetype-speci c metric using the same capability. A simple demonstration of this capability focused on generating time-dependent cash ows for reactor deployment that could then be analyzed in di erent ways. Cyclist, a dedicated application for exploration of Cyclus results, was developed. It's primary capabilities at this stage are best-suited to experienced fuel cycle analysts, but it provides a basic platform for simpler visualizations for other audiences. An important part of its interface is the ability to uidly examine di erent slices of what is fundamentally a ve-dimensional sparse data set. A drag-and-drop interface simpli es the process of selecting which data is displayed in the plot as well as which dimensions are being used for

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2017

Uranium from Seawater Cost Analysis: Recent Updates

While it is not meant to be a direct competitor with conventionally mined uranium, seawater uranium has significant potential to sway policy makers and the public toward the long term viability of nuclear power. Given the large mass of uranium contained within the ocean and its continual replenishment by freshwater run-off and the ocean floor, seawater uranium can be considered for all practical purposes a renewable resource. In addition to this assurance of supply security placing nuclear power on equal footing with other renewable energy generation technologies, seawater uranium removes a key uncertainty by establishing a cost ceiling on uranium based fuels. Given the evolving nature of this technology, this paper aims to provide an update of the economic model to reflect recent progress. This analysis will reference a passive collection system currently under development by Oak Ridge and Pacific Northwest National Labs. This system consists of a polymer modified to contain amidoxime functional groups, a ligand with high uranium affinity. The adsorbing material is then braided into long segments so it may be moored to the bottom of the ocean where it passively collects uranium for a period on the order of weeks to months. Upon completion of its soaking campaign adsorbent is winched to the surface by work boats so the uranium may be eluted off the braids. After a chemical rinse the braids may then be redeployed for another soaking campaign and uranium elution. The adsorbent can be redeployed as many times as is economically feasible, which is a function of the degradation the material suffers upon each reuse. Noteworthy experimental progress has tightened the gap separating estimates of the optimistic and pessimistic case uranium production cost relative to the most recent analysis. It has been demonstrated before that significant uncertainty in adsorbent performance, and thus recovery cost, arises primarily from variability in adsorbent degradation upon reuse and the effects of marine biofouling on uptake. While the underlying recovery mechanism remains, significant changes have been made regarding the method of adsorbent synthesis, propagating to improvements in adsorbent durability. Additionally, further experimentation regarding the area of marine biofouling has tightened the range of expected adsorbent performance when placed in true marine conditions.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2017

Cost Analysis of Wind and Uranium from Seawater Acquisition symbiotic Infrastructure using Shell Enclosures

At current consumption rates, global conventional reserves of uranium, estimated to be 7.6 million tonnes, could be depleted in a little over a century. As these reserves decrease, extraction of uranium is expected to shift to lower quality sites, resulting in higher extraction costs and greater environmental impact. Fortunately, the ocean contains approximately 4.5 billion tonnes of uranium, as uranyl ions at low concentrations of about 3 ppb. Uranium from seawater is a widely studied topic due to the long term security it can assure the nuclear fuel cycle. Additionally, harvesting uranium from seawater could reduce some of the environmental impacts associated with the recovery of land-based uranium. Seawater uranium is meant to create a cost ceiling that provides economic stability and potential savings, not to act as a direct competitor to terrestrial uranium. A recent review of uranium recovery technologies by found uranium adsorption by chelating polymers to be the most promising in terms of adsorbent capacity, environmental footprint, and cost. In this technology, chelating polymers are deployed in seawater and remain submerged until the amount of captured uranium approaches the adsorption capacity. Then, an elution bath is used to strip metal ions, such as uranium, off the adsorbent polymer. A polymer may be immersed in a number of elution baths before it is regenerated by an alkali wash to free its functional groups, allowing for the reuse of the polymer. The output from the elution process undergoes purification and precipitation typical for mined uranium to produce yellowcake. Offshore systems for the extraction of uranium from seawater have been developed since the early 2000's. The system currently studied by a nationwide consortium of national laboratory and university partners utilizes continuous adsorbent polyethylene fibers that are braided around a porous polypropylene float which can be made into long lengths. However, because this deployment scheme requires the adsorbent be brought to a mother-ship for the elution process and redeployed afterward, it has significant practical and economic deployment challenges. Detailed economic analysis have identified the adsorbent production and mooring as the most expensive components of the recovery process. Based on these results, proposed an alternative deployment method that is attached to an offshore wind turbine and continuously takes the adsorbent, that is fabricated into a belt, from the ocean through an elution process and before submerging it back into the sea. However, it has been found that adsorbents with high tensile strength and durability often have very low uranium adsorption properties. Hence, the Wind and Uranium from Seawater Acquisition symbiotic Infrastructure (WUSABI) previously studied, which requires the adsorbent into a belt held in tension, could face difficulties in an ocean environment. Instead, the design, further referred to in this paper as WUSABI-Koosh, utilized a two-part system to decouple the mechanical and chemical needs of an adsorbent for seawater harvesting of uranium. In these designs, the uranium adsorbent material with high adsorbent capacity is enclosed in a hard permeable outer shell with sufficient mechanical strength and durability for use in an offshore environment and chemical resilience against elution treatments. The integration of the design of a uranium harvesting system into an offshore wind turbine tower is pursued because the development of offshore wind or uranium harvesting by themselves bears a high capital cost for the structures, but if the mooring function can be shared, the overall cost for each will be lower. Furthermore, initial design analysis and prototyping of these symbiotic systems has proven they are technically feasible. This paper presents preliminary cost analysis for comparison to uranium recovery via alternative deployment schemes.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2017

Use of NAA to Detect Uptake of Uranium and other Elements in Adsorbents

A consortium of national lab and university partners, led by Oak Ridge (ORNL) and Pacific Northwest (PNNL) National Laboratories, has been working on the development of fibers with the ability to passively adsorb uranium out of seawater. In experiments by PNNL, the adsorption capacity of these fibers was observed to decrease by up to 30% as an effect of marine biofouling. In order to increase the cost-effectiveness of the process, the project ultimately aims to mitigate the effect of fouling by adding antimicrobial agents such as Ag nanoparticles to the adsorbents. To work towards this goal, a method of producing fiber surrogates for the specialized uranium adsorbents was established. This enabled researcher to complete fouling trials at a faster rate and lower cost. Additionally, the project has proven Neutron Activation Analysis (NAA) to be a viable process for measuring the uptake in fibers. The technique stands out because of its ability to measure low concentrations of uranium and other elements with high sensitivity.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2017

Steam Accumulator Storage Integration into a Nuclear Power Plant

The growth of non-dispatchable renewables benefits technologies with flexible load capabilities. Baseload technologies must accept low prices and revenues during low-demand periods that arise with increasing frequency as renewables deployment grows. For this reason, generators such as combined cycle gas turbines threaten to out-compete baseload, and nuclear power plants are facing early retirement. If utilities are to consider future nuclear power plants to be attractive investments they must excel at roles other than baseload generation. Energy storage offers a means to avoid times of low prices and capitalize on times of high prices, as well as for nuclear to participate in ancillary markets and provide grid stability and regulation services. This paper explores the use of steam accumulators to store energy for a pressurized water reactor (PWR). The discharging steam from the accumulator provides heat to a feedwater heater, replacing steam, which bleeds off of the high-pressure turbine during normal operation. The utilization of the accumulator as a heat source for the feedwater heater increases the electrical power output of the PWR during discharge, as more electricity can be produced for a constant thermal input from the steam generator. This study first presents the proposed layout of the steam accumulator integrated into a PWR and the base case values used. Next a brief overview of the thermodynamic model governing the charging and discharging processes of the accumulator is presented. An economic model describes the capital cost estimation and revenue potential for the system. These models are evaluated at varying values of energy, power, and pipe lengths. Results show the relationship between energy, power, and accumulator size, and their effect on net annual revenue and storage efficiency. The cases presented here provide direction for future work for optimizing the size and power output of the accumulator.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Cost and Systems Analysis of Innovative Fuel Resources Concepts

Economically recovered uranium from seawater can have a transformative effect on the way policy makers view the long-term viability of uranium based fuel cycles. Seawater uranium, even when estimated to cost more than terrestrially mined uranium, is integral in establishing an economic backstop, thus reducing uncertainty in future nuclear power costs. While a passive recovery scheme relying on a field of polymer adsorbents prepared via radiation induced grafting has long been considered the leading technology for full scale deployment, non-trivial cost and logistical barriers persist. Consequently, university partners of the nation-wide consortium for seawater uranium recovery have developed variants of this technology, each aiming to address a substantial weakness. The focus of this NEUP project is the economic impacts of the proposed variant technologies. The team at University of Alabama has pursued an adsorbent synthesis method that replaces the synthetic fiber backbone with a natural waste product. Chitin fibers suitable for ligand grafting have been prepared from shrimp shell waste. These environmental benefits could be realized at a comparable cost to the reference fiber so long as the uptake can be increased or the chemical consumption cost decreased.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Theoretical neutron damage calculations in industrial robotic manipulators used for non-destructive imaging applications

Our paper describes how to use MCNP to evaluate the rate of material damage in a robot incurred by exposure to a neutron flux. The example used in this work is that of a robotic manipulator installed in a high intensity, fast, and collimated neutron radiography beam port at the University of Texas at Austin's TRIGA Mark II research reactor. Our effort includes taking robotic technologies and using them to automate non-destructive imaging tasks in nuclear facilities where the robotic manipulator acts as the motion control system for neutron imaging tasks. Simulated radiation tests are used to analyze the radiation damage to the robot. Once the neutron damage is calculated using MCNP, several possible shielding materials are analyzed to determine the most effective way of minimizing the neutron damage. Furthermore, neutron damage predictions provide users the means to simulate geometrical and material changes, thus saving time, money, and energy in determining the optimal setup for a robotic system installed in a radiation environment.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2016

A Higher Fidelity Cost Analysis of Wind and Uranium from Seawater Acquisition symbiotic Infrastructure

The vastness of the worlds oceans makes the low concentration of naturally existing uranium, 3.3 ppb, appealing as a recoverable natural resource. Although ample uranium is available currently through conventional means, uranium from seawater is a widely studied topic due to the long term security it can assure the nuclear fuel cycle. It is important to mention that seawater uranium is not meant to act as a direct competitor to terrestrial uranium, but instead create a cost ceiling that provides economic stability and potential savings. Additionally, seawater uranium could circumvent some of the environmental impacts associated with recovery of any land based resource. The system currently studied by a nation-wide consortium of national lab and university partners involves the passive recovery of uranium using polymer based adsorbents. High Density Polyethylene fibers undergo a radiation induced graft co-polymerization process involving amidoxime, to attract uranium, and a polar co-monomer to increase hydrophilicity. After further chemical conditioning adsorbent fibers are braided into 60 meter strands for marine deployment. Braids are moored to the ocean floor for the duration of their soaking campaign. After sufficient seawater exposure they are winched up so the adsorbed uranium may be eluted off the braids. This deployment and elution process is repeated multiple times before the adsorbent's ultimate disposal, where its lifetime is dictated by the degradation it suffers with each re-cycle. Previous economic analyses have identified the adsorbent production and mooring as the most expensive components of the recovery process. Therefore, a later publication by Picard et al. proposed an alternative deployment method in an effort to reduce seawater uranium production cost. The Wind and Uranium from Seawater Acquisition symbiotic Infrastructure (WUSABI) couples uranium recovery with off shore wind to reduce mooring capital cost. The uranium harvesting structure attached to the underwater base of the wind turbine supports elution tanks and an adsorbent pulley system. This allows for a nearly autonomous mooring and elution procedure as adsorbent is in constant motion, reaching the elution tanks at the end of its soaking campaign. Although the original publication did include a short economic section, further analysis was carried out to provide a higher fidelity production cost estimate for uranium recovered by this system. Sufficient detail was provided regarding the capital and operating costs of the novel uranium harvesting units. The adsorbent production and uranium elution and purification steps however were estimated by simpler methods, for example applying a previously reported cost for producing a unit mass of adsorbent. This methodology, although satisfactory for the zeroth-order approximation desired in the original publication, overlooks many of the complexities and feedbacks embedded in the full cost model, which are necessary to provide a more accurate estimate. Perhaps more importantly, given the constant updates regarding adsorbent synthesis and performance this value quickly become outdated. Syncing an improved estimate for the WUSABI harvesting units with the existing economic analysis for adsorbent production and elution, which evolves in tandem with the technology, provides a more robust production cost estimate that will remain current over time. In addition to the updates and higher level of detail provided in this independent analysis, consistency in methodology allows for accurate comparison of uranium production costs across recovery methods. (authors)

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2016

An Economic Model of a Steam Accumulator Storage System for Nuclear Power Plants

The growth of non-dispatchable renewables benefits technologies with flexible load capabilities. Baseload technologies must accept low prices and revenues during low-demand periods that arise with increasing frequency as renewables deployment grows. For this reason, generators such as combined cycle gas turbines threaten to out-compete baseload, and nuclear power plants are facing early retirement. If utilities are to consider future nuclear power plants to be attractive investments they must excel at roles other than baseload generation. Energy storage offers a means to avoid times of low prices and capitalize on times of high prices, as well as for nuclear to participate in ancillary markets and provide grid stability and regulation services. This work explores the design of a steam accumulator system that can store energy from a nuclear plant. An economic model is created to determine the market conditions that will produce a profitable system. An energy storage capacity of 500 MWh is chosen as a base case, but the energy to power ratio (E/P ratio) is varied in sensitivity analyses while holding energy fixed. This paper first presents the proposed size and layout of the steam accumulator system. Next, it provides an overview of the thermodynamic model, which is used to determine the system size for base case conditions. An economic model is presented with sensitivity analyses, which show the effect of price volatility on net revenue. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2016

Uranium from Seawater Cost Analysis: Recent Updates

Uranium from seawater can act as an economic backstop by putting an effective ceiling on the cost of recovering uranium. Although it is not meant to be a direct competitor with conventionally mined uranium there is significant effort, by a consortium of five national labs and ten universities, to improve the recovery process. Accurately predicting the cost associated with this method of uranium production is an important factor in determining a cost ceiling for uranium fuels and assuring supply security for uranium based nuclear fuel cycles. Given the evolving nature of this technology, this paper aims to provide an update of the economic model to reflect recent progress. The recovery system analyzed here is a passive collection process under persistent development by Oak Ridge and Pacific Northwest National Labs (ORNL and PNNL). The process relies on an amidoxime based uranium adsorbents constructed by co-grafting an amidoxime precursor and a hydrophilic comonomer onto a high density polyethylene (HDPE) backbone. After further chemical processing the adsorbent fibers are braided into 60 meter segments. The braids are then sent out to sea where they are moored to the bottom of the ocean. Upon realization of their soaking campaign the braids are winched up so the uranium may be eluted off the adsorbent. The acidic chemicals used in the elution process require an alkaline regeneration procedure to be applied to the adsorbent before it can be redeployed for another campaign. The deployment and elution process is repeated as many times as economically feasible, as dictated by the severity of degradation suffered by the braid due to the elution process and exposure to seawater. A large number of design and deployment parameters influence the final uranium production cost. Some are strongly affected by the chemical technologies, such as uranium uptake and degradation rate, while others are operational parameters, such as number of adsorbent uses and length of soaking campaign. Still others are both intrinsic and affected by operational choices, such as the ocean temperature and degree of oceanic biofouling. Recent experiments have been focused on improved characterization of the effect of: oceanic temperature, a novel elution method, adsorbent degradation rates, and oceanic biofouling, and they will therefore be the focus of this paper. The degradation results presented here are likely to represent a worst case scenario. Since chemically similar adsorbents were able to achieve a much lower degradation rate with the previous acidic elution process it is very possible that modifications can be made to the new adsorbents to ameliorate the degradation suffered, especially with the new bicarbonate elution process, which is believed to be less harsh. Similarly, the 30% loss in uptake suffered as a result of biofouling is likely an upper-bound. The experiments were conducted in full light and at 20 deg. C. In reality however the braids will be submersed approximately 100 meters beneath the surface, potentially subject to a temperature gradient that may influence biofouling patterns. Also the light reaching the adsorbent surface may not be as intense as in laboratory conditions due to seawater turbidity and shadows cast by nearby braids. In light of these factors, it is appropriate to present a range of costs, reflecting the best and worst case scenarios of all of the parameters considered here. Table II shows the updated parameter ranges and uranium production costs. Ongoing work, particularly into the mitigation of biofouling and degradation, is expected to tighten this cost range and reduce the predicted cost. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2016

Value of Information in Fuel Cycle Decision-making

Transitions between nuclear fuel cycles with uncertain key parameters (e.g., SNF and HLW disposal costs, fast reactor capital costs) have been examined using a decision-making under uncertainty methodology. The methodology explicitly incorporates uncertainties in key parameters into the decision-making process by constructing a stochastic model and embedding uncertainties as bifurcations in the decision-tree. The framework of this methodology allows for interpretation using a real options valuation or game theoretic approach, reviewed in. The work presented here extends the decision-making under uncertainty framework to calculate the value of information, which may be used to inform a game against nature. These games against nature have been applied to resource allocation problems, where scarce resources are allocated to maximize expected payoffs. More broadly, the value of developing alternative technologies may be considered under the same framework, where an investment portfolio for technology deployment may be developed. Here, the value of information is taken as the value of reducing uncertainty in key parameters, and these values may be substituted for the traditional payoff matrix when considering allocating scarce resources. Games against nature may provide a unique perspective on R and D funding decisions when considering transitions between nuclear fuel cycles. By determining the value of reducing uncertainties (of gaining information on probability distributions) scarce resources may be allocated in such a way to maximize their utility. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2016

An Integrated Fuel Depletion Calculator for Fuel Cycle Options Analysis

Bright-lite is a reactor modeling software developed at the University of Texas Austin to expand upon the work done with the Bright [1] reactor modeling software. Originally, bright-lite was designed to function as a standalone reactor modeling software. However, this aim was refocused t couple bright-lite with the Cyclus fuel cycle simulator [2] to make it a module for the fuel cycle simulator.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2015

Uranium Removal from Seawater by Means of Polyamide 6 Fibers Directly Grafted with Diallyl Oxalate through a Single-Step, Solvent-Free Irradiation Process

In order to test the effectiveness of oxalate-based polymeric adsorbents in the recovery of uranium from seawater, diallyl oxalate (DAOx) was grafted onto nylon 6 fabrics by exposing the fabric, immersed in pure liquid DAOx or in a surfactant-stabilized dispersion of DAOx in water, to electron beam or gamma radiation. Following drying and weighing to determine the degree of grafting (DoG), the presence of oxalate in the fabrics was verified using XPS. Zeta potential measurements showed the fabric surfaces to be negatively charged. The fabrics were tested by rotating them for 7 days in a rotary agitator with actual seawater spiked with 0.2 or 1.0 mg∙L -1 uranium. The fraction of uranium in the solution which was removed due to uptake on the fabrics was found to rise with increasing DoG at both uranium concentrations. EDS measurements were used to map the distribution of adsorbed uranium on the polymeric fibers.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗