Features

Diakont technicians prepare an NDE inspection robot for deployment into a diesel tank. Photos: Diakont

Robotics and remote systems have been used for supporting nuclear facilities since the dawn of the atomic age. Early commercial nuclear plants implemented varying levels of automation and remote operation, such as maintenance activities performed on the reactor pressure vessel and steam generators. Over the past several decades, there has been a steady progression toward incorporating more advanced remote operations into nuclear plants to improve their efficiency and safety. One of the primary forces driving the adoption of robotic tooling in U.S. nuclear power plants is money.

The economic model for the U.S. operating fleet has changed considerably over the past 10 to 12 years. Regulations in the nuclear industry have rarely decreased and, more often than not, have increased. This has led to nuclear plants in certain energy markets being hindered financially and thus needing to find ways to optimize their operations to do more with the resources they have. At the same time, the reliability and flexibility of robotics and automated systems have been increasing while their costs have been decreasing, making robotic systems much safer and more available to use. This has helped drive utilities to explore new ways of using robotics to overcome the obstacles they are facing. One of the obstacles that power plants have been tackling has been shortening the duration of their refueling outages to decrease their costs and increase their revenue.

Joe Dixon

Hubert Hafen

Wälischmiller Engineering (HWM), of Markdorf, Germany, has joined forces with NuVision Engineering (NVE) to form NuVision-Wälischmiller under parent company Carr’s Engineering. The NVE-HWM team develops, demonstrates, and deploys engineered remote systems and robotics to meet the high safety standards, quality requirements, and challenging demands of the nuclear industry.

HWM specializes in remote-handling and robotic solutions for hazardous applications. Since 1946, HWM has been delivering a range of remote-handling solutions, including precision manipulators, tools, and controllers, to the nuclear industry.

NVE, founded in 1971, is headquartered in Pittsburgh, Pa., with major operational facilities in Charlotte, N.C. The company delivers engineered solutions and services to its customers in the nuclear markets of commercial power, research, isotope production, and government cleanup sectors. NuVision develops, demonstrates, and deploys technology-based solutions that help extend the life and safe operation of power plants, improve new plant designs, and remediate government-owned legacy waste sites.

Joe Dixon is the robotics director at NVE. For nearly 20 years, he has provided solutions for the global nuclear industry and has conceived, designed, fabricated, deployed, and managed teams for advanced robotics, isotope production, scientific research, decommissioning, energy production, process maintenance, and remote handling. Having worked on large projects around the world, Dixon is one of the industry’s leaders in remote-handling and robotics technologies.

Hubert Hafen is the chief technology officer for HWM. With more than 30 years of experience in the nuclear industry, Hafen has served as chief engineer and project manager for a large number of international remote-handling projects, such as remote-handling equipment for the decommissioning of the Greifswald nuclear power plant in Germany, the decommissioning of the reprocessing plant in Karlsruhe, Germany, planning for the remote equipment for the ITER project, and several remote-handling projects in Japan, Russia, China, the United Kingdom, France, and Germany. His ability to present clients with problem solving has made him renowned in the robotics world.

Dixon and Hafen talked recently with Nuclear News editor-in-chief Rick Michal about what is new in robotics and remote-handling systems.

The U.K. National Nuclear Laboratory’s Colin Fairbairn (left) and Ben Smith (in pre-COVID days) work on the Box Encapsulation Plant (BEP) robots project at the NNL’s facility in Workington, Cumbria, U.K. Photos: UKNNL

Though robotics solutions have been used across many industries, for many purposes, Sellafield Ltd has begun to bring robotics to the U.K. nuclear industry to conduct tasks in extreme environments. The Sellafield site, in Cumbria, United Kingdom, contains historic waste storage silos and storage ponds, some of which started operations in the 1950s and contain some of the most hazardous intermediate--level waste in the United Kingdom. There is a pressing need to decommission these aging facilities as soon as possible, as some of them pose significant radiation risk.

You may have read the abbreviated version of this article in the November 2020 issue of Nuclear News. Now here's the full article—enjoy!

I have enjoyed a long and stimulating career in applied nuclear physics—specifically nuclear reactor physics, nuclear fusion plasma physics, and nuclear fission and fusion reactor design—which has enabled me to know and interact with many of the scientists and engineers who have brought the field of nuclear energy forward over the past half-century. In this time I have had the fortune to interact with and contribute (directly and indirectly) to the education of many of the people who will carry the field forward over the next half-century.

The Zephyr system uses probes for steam generator inspections. Photos: APS

The Palo Verde Nuclear Generating Station, a three-unit pressurized water reactor plant operated by Arizona Public Service Company, has started using an inspection technology relatively new to the nuclear industry. The technology, called smart pigs (an acronym for “piping inline gauges”), has previously been employed by oil and gas companies for inspecting and cleaning underground pipes. After testing and analyzing smart pig products from several companies, Palo Verde’s underground piping consultant, Dan Wittas, selected a smart pig suitable for navigating the tight-radius bends in the plant’s spray pond piping. The spray pond system consists of piping, a pump, and a reservoir where hot water (from the Palo Verde plant) is cooled before reuse by pumping it through spray nozzles into the cooler air. Smart pigs work by using the water’s flow through the piping to move an inspection tool within the pipe itself. The technology replaces the previous method of pipe inspection, in which various relatively small sections of piping were unearthed and directly inspected, and were considered to be representative examples of the overall piping condition. In contrast, the smart pigs obtain corrosion levels for the length of piping traveled through and allow a corrosion baseline to be established.

Reactor operators Craig Winder (foreground) and Clint Weigel prepare to start up the ATRC Facility reactor at Idaho National Laboratory after a nearly two-year project to digitally upgrade many of the reactor’s key instrumentation and control systems. Photos: DOE/INL

At first glance, the Advanced Test Reactor Critical (ATRC) Facility has very little in common with a full-size 800- or 1,000-MW nuclear power reactor. The similarities are there, however, as are the lessons to be learned from efforts to modernize the instrumentation and control systems that make them valuable assets, far beyond what their designers had envisioned.

One of four research and test reactors at Idaho National Laboratory, the ATRC is a low-power critical facility that directly supports the operations of INL’s 250-MW Advanced Test Reactor (ATR). Located in the same building, the ATR and the ATRC share the canal used for storing fuel and experiment assemblies between operating cycles.

On March 9, the Department of Energy’s Office of Environmental Management (EM) released its first strategic plan in several years. Titled “A Time of Transition and Transformation: EM Vision 2020-2030,” and called the Strategic Vision¹, the document outlines the past accomplishments in cleaning up legacy nuclear waste and provides a broad overview of the initiatives that EM plans to put into motion over the next decade, “laying the groundwork for a long-term plan to realize meaningful impact on the environmental cleanup mission.”²

Within the energy sector, the management of projects and megaprojects has historically focused on the planning and delivery of the construction of infrastructure [1–3]. Therefore, policies are more oriented to support the construction of infrastructure rather than its decommissioning. Globally, however, a number of facilities have reached or will soon reach their end of life and need to be decommissioned.

These facilities span the energy sector, including nuclear power plants, oil and gas rigs, mines, dams, etc., whose decommissioning present unprecedented technical and socioeconomic challenges [4–7]. Moreover, the cost of decommissioning and waste management of this array of infrastructure is estimated to reach hundreds of billions of dollars and, for most of these projects, keeps increasing, with limited cross-sectorial knowledge-transfer to mitigate the spiraling increase of these figures.

Cross-sectorial knowledge-transfer is one way to tackle this matter and improve the planning and delivery of decommissioning projects. The aim of our research has been to build a roadmap that is designed to promote the sharing of good practices between projects both within the same industry and across different industrial sectors, focusing specifically on major decommissioning and waste-management challenges.

To reach this aim, our research leverages on the experience of senior industry practitioners and their involvement in the decommissioning and waste management of infrastructure in different sectors. More specifically, this research addresses the following questions:

To what extent can lessons learned be transferred across industrial sectors?

What are the challenges that hinder successful cross-sectorial knowledge-transfer?

Six large trucks were used to push and pull the SONGS-1 reactor pressure vessel 400 miles through Nevada and into Utah with a maximum speed of 10 miles per hour over a 10-day period. Photo: EnergySolutions

July 14 marked a milestone in the decommissioning of the San Onofre Nuclear Generating Station (SONGS), as the Unit 1 reactor pressure vessel (RPV) completed a seven-week journey from Southern California to EnergySolutions’ Clive disposal facility in Utah. The approximately 670-ton RPV package, containing the pressure vessel from the previously decommissioned SONGS-1, pieces of radioactive metal, and grout for radiation shielding, left San Onofre on May 24, traveling by rail to a location outside Las Vegas, where it was transferred to a platform trailer to be transported the remaining 400 miles to Clive, about 75 miles west of Salt Lake City.

“This project was a very complex undertaking that required approvals and/or coordination with over two dozen federal, state, and local agencies and government entities,” said Todd Eiler, director of the EnergySolutions Projects Group, which handled the transport. “The coordinated effort with the rail lines and departments of transportation in California, Nevada, and Utah resulted in another safe and successful large component shipment managed by the EnergySolutions Projects Group.”

Radiation has benefited mankind in many ways, including its use as an energy source and an indispensable tool in medicine. Since the turn of the 20th century, society has sought ways to harness its potential, while at the same time recognizing that radiological exposures need to be carefully controlled. Out of these efforts, and the work of many dedicated professionals, the principles of justification, optimization, and limitation have emerged as guiding concepts.

Justification means that the use of radiation, from any radiation source, must do more good than harm. The concept of optimization calls for the use of radiation at a level that is as low as reasonably achievable (ALARA). Dose constraints, or limitation, are meant to assist in reaching optimization and protection against harm by setting recommended numerical levels of radiation exposure from a particular source or sources. Together, these three principles form the bedrock of the international radiation protection system that drives decision-­making and supports societal confidence that radiation is being used in a responsible manner.

The National Academies of Sciences, Engineering, and Medicine (NAS) has begun a new webinar series, with the first entry titled “What’s new in low-dose radiation.” The July 22 event kicked off the Gilbert W. Beebe Webinar Series—an extension of the Beebe Symposium, which was established in 2002 to honor the scientific achievements of the late Gilbert Beebe, NAS staff member and designer/implementer of epidemiologic studies of populations exposed to the atomic bombings of Hiroshima and Nagasaki as well as the Chernobyl accident.

Nuclear energy is faced with a number of challenges in a changing energy landscape, driven by the need to reduce carbon emissions to mitigate climate change. Renewable energy technologies are being considered as the solution to climate change and are increasingly being deployed across the world. However, renewable energy sources, particularly solar and wind, are highly variable, and deployment of these technologies has resulted in significant perturbances in the energy market, raising questions about grid stability and the adaptability of other sources to compete in a changing marketplace that prioritizes renewables. Nuclear plants, well suited for baseload operation, have demonstrated technical capability and flexibility to respond to the fluctuating demand; however, they have also discovered that the economics of such operating mode are not necessarily optimal to their financial security. On the other hand, despite contributing to the carbon emissions, the low cost of abundantly available natural gas and resultant low-cost electricity have exacerbated the economic pressure on nuclear technologies, raising questions about their survival and role in future energy systems¹.

Limerick Nuclear Power Plant

Refueling a nuclear reactor under normal circumstances can be a challenging endeavor, with hundreds of maintenance activities and inspections to perform in a short window of time, and more than a thousand supplemental workers on-site to complete the work safely and effectively. But these are anything but normal circumstances.

Around the world in the mid-March time frame, conditions were changing rapidly due to the COVID-19 pandemic, as was everyone’s understanding of it. For nuclear power plants, the pandemic meant dealing with new government regulations and restrictions that were put in place. “U.S.-based support of international clients was especially challenging,” said Mike Little, president and principal officer of Reston, Va.–based Dominion Engineering Inc. (DEI). “With border closures going into effect, we were not only focusing on the health and safety of our workers abroad, but also making sure they would be able to return home. Providing remote subject matter expertise from the U.S. through our international service partners was critical to successful job execution during this time.”

Mary Lou Dunzik-Gougar said she feels very fortunate to be taking on the role of president of the American Nuclear Society at this moment in history. “By that, I don’t mean at the time of the COVID-19 pandemic,” she quickly clarified. “I mean at a time when we are making exciting and transformational changes to the Society.”

These changes are described in the aptly named Change Plan 2020, which was developed by a group that included ANS past presidents Andy Klein, Gene Grecheck, and Bob Coward, with input from members, including Dunzik-Gougar, and was approved by the ANS Board of Directors at the November 2019 ANS Winter Meeting in Washington, D.C. Already, Change Plan 2020 has reshaped the way the Society interacts with its members, including a new, greatly improved website and an updated, more vibrant and informative Nuclear News magazine. The plan has also reorganized the Society to create, in the words of ANS’s new executive director and chief executive officer, Craig Piercy, a “more streamlined, less siloed organization that is better equipped to meet our members’ needs going forward.”

The Ghana Research Reactor-1, located in Accra, Ghana, was converted from HEU fuel to LEU in 2017. Photo: Argonne National Laboratory

In late 2018, Nigeria’s sole operating nuclear research reactor, NIRR-1, switched to a safer uranium fuel. Coming just 18 months on the heels of a celebrated conversion in Ghana, the NIRR-1 reboot passed without much fanfare. However, the switch marked an important global milestone: NIRR-1 was the last of Africa’s 11 operating research reactors to run on high-enriched uranium fuel.

The 40-year effort to make research reactors safer and more secure by replacing HEU fuel with low-enriched uranium is marked by a succession of quiet but immeasurably significant milestones like these. Before Africa, a team of engineers from many organizations, including the U.S. Department of Energy’s Argonne National Laboratory, concluded its conversion work in South America and Australia. Worldwide, 71 reactors in nearly 40 countries have undergone conversions to LEU, defined as less than 20 percent uranium-235. Another 31 research reactors have been permanently shut down.

As industry steps up its efforts to design, develop, and deploy advanced reactors, codes and standards must be developed to support these technologies. Toward that end, ANS and the Nuclear Energy Institute collaborated to host a virtual workshop on June 23 for industry partners to discuss the development of advanced reactor codes and standards.

NEI’s senior director of new reactors, Marc Nichol, welcomed more than 400 attendees to the online meeting, and ANS’s director of government relations, John Starkey, outlined the meeting logistics.

We often define noise as an unwanted disturbance, especially acoustic in nature. Neutron noise, by contrast, is a direct measure of the dynamics of a nuclear core. It can be used for core monitoring without disturbing plant operation and by using the existing core instrumentation. The European CORTEX project aims to develop an innovative core monitoring technique using neutron noise, while capitalizing on the latest developments in neutronic modeling, signal processing, and artificial intelligence.

With a new generation of nuclear reactors in the works, Idaho National Laboratory has embraced digital engineering (DE) as a means of achieving the same efficiencies that companies in the private sector have been able to realize in everything from concert halls to aircraft engines.

DE—using advanced technologies to capture data and craft design in a digitized environment—has been evolving since the 1990s. For Mortenson Construction, a worldwide construction firm, using virtual design and construction resulted in a cumulative 600 days saved over 416 projects and a 25 percent increase in productivity. By building digital twins for assets, systems, and processes, DE has avoided more than $1.05 billion in customer, production, and mechanical losses.

Leaders at INL recognized in 2018 that DE could be useful in the design and construction of new commercial and test reactors. Managing construction costs, timing, and performance will be essential to maintain U.S. competitiveness.