Moltex Energy Canada has been granted a patent for its used nuclear fuel recycling process in Canada. The patent covers Moltex’s process for converting any uranium oxide fuel into molten salt reactor fuel, known as WAste To Stable Salt (WATSS). Using this process, used fuel is converted into several parts. Transuranics – the long-lived, man-made elements – along with some uranium and fission products are extracted into a salt.
This salt is the fuel for Moltex’s Stable Salt Reactor – Wasteburner (SSR-W) design, avoiding the need for high-purity separations. The SSR-W and some other reactors could use this fuel, converting it to energy while destroying long-lived waste products created by nuclear fission. This would significantly reduce waste stockpiles.
Uranium, close to its natural state and considered intermediate or low-level waste, is a major by-product of the process that can have other uses. According to Moltex, the small by-product of the fission products can be disposed directly or used as a heat source for remote applications, until it has decayed and then contains valuable stable elements.
Conventional reprocessing either directly produces pure plutonium, or can be altered to produce pure plutonium. The WATSS process is unable to produce pure plutonium, making the process inherently safer. Moltex says this also makes the process simpler and less expensive.
“This patent is testament to Moltex’s commitment to innovation and to finding improvements in existing nuclear energy processes,” said Rory O’Sullivan, CEO, Moltex. “Waste is one of the most important considerations in the nuclear industry, and Moltex’s process offers an elegant and cost-effective solution to safely reducing waste stockpiles.” The patent is one of over 600 patents granted to Moltex co-founder and chief scientist Dr Ian Scott.
Moltex says it is developing “three unique technologies”: the SSR-W; the WATSS process; and GridReserve thermal energy storage tanks, enabling the SSR-W to act as a peaking plant. Moltex was selected by NB Power to progress development of its reactor technology in New Brunswick with the goal of deploying first-of-a-kind SSR-W, WATSS and GridReserve units at the Point Lepreau NPP site by the early 2030s.
Moltex says the SSR-W “has reached a technology readiness level that inspires confidence in its feasibility and economic viability, allowing the technical team to reallocate resources toward the optimisation of the WATSS process”.
Image: Cutout of a stable salt reactor core
