ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
Latest Magazine Issues
Apr 2024
Jan 2024
Latest Journal Issues
Nuclear Science and Engineering
May 2024
Nuclear Technology
Fusion Science and Technology
Latest News
Glass strategy: Hanford’s enhanced waste glass program
The mission of the Department of Energy’s Office of River Protection (ORP) is to complete the safe cleanup of waste resulting from decades of nuclear weapons development. One of the most technologically challenging responsibilities is the safe disposition of approximately 56 million gallons of radioactive waste historically stored in 177 tanks at the Hanford Site in Washington state.
ORP has a clear incentive to reduce the overall mission duration and cost. One pathway is to develop and deploy innovative technical solutions that can advance baseline flow sheets toward higher efficiency operations while reducing identified risks without compromising safety. Vitrification is the baseline process that will convert both high-level and low-level radioactive waste at Hanford into a stable glass waste form for long-term storage and disposal.
Although vitrification is a mature technology, there are key areas where technology can further reduce operational risks, advance baseline processes to maximize waste throughput, and provide the underpinning to enhance operational flexibility; all steps in reducing mission duration and cost.
Marius Zamfirache, Anisia Bornea, Ioan Stefanescu
Fusion Science and Technology | Volume 71 | Number 4 | May 2017 | Pages 590-594
Technical Note | doi.org/10.1080/15361055.2016.1273698
Articles are hosted by Taylor and Francis Online.
ICSI Rm. Valcea is the leading research institute involved in the Romanian heavy water detrititiation program. ICSI has built a Tritium Removal Facility which is an experimental pilot plant for deuterium and tritium separation - its main objectives being to demonstrate detritiation technology followed by implementation at the CANDU nuclear power plant in Cernavoda.
Within isotope separation installations using a cryogenic distillation process, the required gas purity must be high to avoid the risk of impurity condensation. A preferred and recommended purification process is solidifying impurities over a large material area heat exchanger device. Such a system is usually a regenerative type to ensure continuous operation. Gas Purification is achieved either by means of reversible heat exchangers or thermal regenerators.
Reversible exchangers and regenerators have a periodic operation, a warm period and a cold period. During the warm period, the heat exchanger or regenerator mass heat up cooling the purified gas, while in the cold period, the cold waste gas heat up the exchanger or the regenerator.
Essentially, the impurity solidification purification process is the same for both the reversible exchanger and regenerator, but because of their differences the process description will be different and so also the design method. Due to periodic operation of a regenerative system the process is unsteady, its description utilizing highly complex mathematics. For this reason it is of particular interest to have a very well developed mathematical description of non-stationary heat exchange processes, incorporating simultaneous mass and heat exchange processes taking place in the regenerative systems.
This paper presents a conceptual scheme of a purification unit consisting of two stages (the first being a drying system followed by an advanced cryogenic purification). A theoretical analysis of the second stage of the process will be developed. Due to cyclic operation (cooling, retention, cleaning) the process is carried-out in the non-stationary regime, thus the mathematical description is complex but needed to design such a system.
Also presented is a theoretical analysis of the purification of an impurity-laden gas, using the calculation model developed with the proposed regenerative system.