Nuclear clean-upNew Materials Could Help Clean-Up Chernobyl and Fukushima

Materials which could be used to help clean-up the Chernobyl and Fukushima nuclear power stations have been developed by engineers at the University of Sheffield.

The materials, produced by Dr. Claire Corkhill and her team from the University’s Department of Materials Science and Engineering, in collaboration with scientists in Ukraine, can simulate the Lava-like Fuel Containing Materials (LFCMs) that are obstructing decommissioning efforts at the nuclear disaster sites.

Published in the journal Nature Materials Degradation, the development is the first time a close approximation of a real LFCM has ever been achieved.

LFCMs are a mixture of highly radioactive molten nuclear fuel and building materials that fuse together during a nuclear meltdown.

During the Chernobyl and Fukushima nuclear accidents, radioactive materials mixed with fuel cladding and other building materials in the reactors and are now incredibly difficult and dangerous to remove from the sites. If left untreated, the LFCMs pose an ongoing radiological safety risk to the local environment.

Sheffield notes that in the case of Chernobyl, the mixture of molten fuel, cladding, steel, concrete and sand formed nearly 100 tons of highly radioactive glass-like lava, which flowed through the nuclear power plant and has solidified into large masses.

The masses present a highly dangerous risk to personnel and the environment in the surrounding area and could remain a hazard for decades, even millennia, unless something can be done to stabilize or remove them. However, very few samples of these meltdown materials are available to study and the masses are often too hazardous for people or even robots to get close to in order to better understand the behavior of the materials.

Dr. Corkhill said: “Understanding the mechanical, thermal and chemical properties of the materials created in a nuclear meltdown is critical to help retrieve them, for example, if we don’t know how hard they are, how can we create the radiation-resistant robots required to cut them out?”

In the new research published today (30 January 2020), the University of Sheffield engineers at the NucleUS Immobilization Science Laboratory (ISL) report their development of small batches of low radioactivity materials that can be used to simulate LFCMs.

These simulated materials have been used to analyze the thermal characteristics and corrosion kinetics of LFCMs, which produced results that are very close to those of real LFCM samples reported by previous studies.