As countries around the world experience resurrection in nuclear power projects, where and how nuclear waste disposal questions are politically frightening about the questions of questioning questions. For example, the United States has stopped its only long -term underground nuclear waste reserves indefinitely. Scientists are using both modeling and experimental methods to study the effects of underground atomic waste disposal and eventually, they hope, create public belief in the decision -making process.
New research of scientists of MIT, Lawrence Berkeley National Lab and University of Orlens progress in that direction. The study suggests that the simulation of underground atomic waste interaction generated by new, high-performance-computing software, a research facility in Switzerland is well aligned with experimental results.
The study appears in the magazine, who was co-authored with MIT PhD student Dauran Sarsenbayev and Assistant Professor Haruko Venrite as well as Christoph TournaSat and Carl Stephell. owner,
“These powerful new computational devices, which combine with real world experiments on the Mont Terry Research Site in Switzerland, help us understand how radionuclides will flee into coupled underground systems,” Sarsenbayev, who is the first author of the new study.
Authors hope that research will improve confidence between policy makers and public in long -term security of underground nuclear waste disposal.
“This research – coupling both calculations and experiments – it is important to improve our confidence in waste disposal safety assessment,” says Venrite. “It is important to validate the disposal routes as an important source to deal with climate change with nuclear power and ensure energy security.”
Compare simulation with experiments
Settlement of atomic waste in deep underground geological structures is currently considered the safest long-term solution for managing high-level radioactive waste. For example, there has been a lot of effort in studying migration behavior of radionuclides from nuclear waste within various natural and engineer geological materials.
Since its establishment in 1996, the Mont Terry Research Site in Northern Switzerland has worked as an important test bed for an international union of researchers interested in studying Opelins Clay-a thick, water-tang mud stone abundant in areas with a tunnel.
“It is widely considered as one of the most valuable real -world experiment sites because it provides us with decades datasets around cement and clay interactions, and they are the major materials that are the major ingredients used for geological repository for engineer barrier systems and geological waste by countries around the world,” Sarsenbayeva explains.
For their studies, Sarsenbayev and Venrite collaborated with co-writers TournaSat and Staffael, who have developed a high-performance computing software to improve modeling of interactions between nuclear waste and engineer and natural materials.
To date, limited scientists in many challenges understand how nuclear waste reacts with cement-clan obstacles. For one thing, obstacles are made of irregularly mixed materials that are deep underground. Additionally, the existing class of the model is usually used to simulate radionuclide interactions with cement-black, do not take into account the electrostatic effects associated with negatively charged soil minerals in obstacles.
Tournassat and steefel’s new software accounts for electrostatic effects, allowing it the only one that can simulate those interactions in a three-dimensional location. A software called crunchoditti was developed with installed software known as crunchflow and was recently updated this year. It is designed to run on several high-demonstration computers at a time in parallel.
For the study, researchers saw a 13-year-old experiment, with initial attention to cement-clean rock interactions. Within several years, the mixture of both negative and positively charged ions was added to the borhole located near the center of the displaced cement. Researchers focus on a 1-gram-ride zone between radionuclides and cement-clashes, called “skin”. He compared his experimental results to software simulation, aligning two datasets.
“The results are quite important because earlier, these models will not fit field data very well,” says Sarsenbayev. “It is interesting that the fine phenomena between cement and soil in ‘skin’, changing over time with physical and chemical properties, can be used to cover experimental and simulation data.”
Experimental results showed that the model is successfully responsible for interacting between electrostatic effects associated with soil -rich formation and content in Mont terry over time.
Sarsenbayev says, “It all works for decades to understand what happens in these interfaces.” “It has been envisaged that this interface has mineral rainfall and porcill clogging, and our results strongly suggest.”
“This application requires freedom of millions of degrees as these multiberar systems require high resolution and much more computational power,” says Sarsenbayev. “This software is actually ideal for using Mont Terry.”
Assessing waste settlement schemes
The new model can now change the old model that has been used to protect and perform the protection and performance of underground geological repository.
“If the US eventually decides to dispose of nuclear waste in a geological reserves, these models can determine the most suitable materials to use,” says Sarsenbayev. “For example, the soil is currently considered a suitable storage material, but salt structures are another potential medium. These models allow us to see the fate of radionuclides on Millennia. We can use them to understand conversations over time that varies from months to many millions of years.”
Sarsenbayev says that the model is appropriately accessible to other researchers and future efforts can be focused on machine learning use to develop less computationally expensive surrogate models.
Further data from the experiment will be available later this month. The team is to compare those data with additional simulation.
“Our partners will originally receive this block of cement and soil, and they will be able to run experiments to determine the exact thickness of the skin along with all the minerals and procedures present in this interface,” Sarsenbayev says. “This is a very big project and takes time, but we wanted to share the initial data and this software as soon as possible.”
For now, researchers hope that their study leads to a long -term solution for storage of nuclear waste that can support policy maker and public.
“This is an interdisciplinary study that includes real -world uses, shown that we are able to predict the fate of radionuclides in sub -collecting,” says Sarsenbayev. “The motto of the Department of Atomic Sciences and Engineering of MIT ‘Science. System. Society.” I think it merges all three domains. ,
