Published on 14 June 2022.
Originally printed in Defense One
The prototype “particle beam cannon” recently completed by Chinese Academy of Sciences’ Institute of Modern Physics may sound like science fiction, but it is a novel new technology that promises to recycle dangerous waste produced by a nuclear reactor. A product of China’s huge investment in advanced nuclear-energy systems, the breakthrough could move the country toward energy independence and further cement its global leadership in climate-friendly technology.
In a typical fission reactor, atoms of heavy isotopes such as uranium-235 are broken apart, releasing energy. The process also releases extra neutrons, which collide with other atoms and break them apart in a chain reaction. The broken atoms are spent fuel that is cooled for a few years and then carefully stored for a few centuries. But a proposed new type of reactor built with this “cannon”—formally, a proton accelerator—could recycle this spent fuel, making it cheaper and safer to generate electricity.
As envisioned, an accelerator-driven system, or ADS, consists of three parts: the proton accelerator launches protons, the spallation target contains the heavy element to be split, and the sub-critical reactor contains the fuel which causes fission. The accelerator fires protons at a heavy element (most likely bismuth) surrounded by a blanket of spent fuel and fresh fissile material (most likely thorium-232 or uranium-238). The target splits apart, releasing neutrons that are absorbed by the spent fuel, turning it back into fissile heavy isotopes—that is, fresh nuclear fuel. Importantly, this process is self-terminating, and does not run the risk of a chain reaction or a meltdown. The Institute of Modern Physics’ completion of a prototype accelerator is a big step toward a working ADS, and a prime example of China’s huge investment in advanced nuclear energy systems paying dividends in new innovations.
Unlike numerous governments that have abandoned nuclear energy entirely, China sees fission as key to a more secure future. Nuclear power is more efficient than wind or solar, and unlike fossil fuels, it does not emit greenhouse gases and particulate air pollution. Ranked second in the world for daily oil consumption, China’s inexorable demand for ever more energy places it in a precarious position. Upwards of 70% of China’s petroleum comes from imports, primarily from the Middle East, and must transit numerous maritime chokepoints. China is slated to spend $440 billion between now and 2035 to build at least 150 more nuclear reactors. If China can continue to develop ADS technology, the waste from these plants can be put to good use and be recycled to produce even more energy for its growing needs.