Moltex Energy Canada Inc has started pre-licensing consultation with the Canadian Nuclear Safety Commission in relation to the development of its Waste to Stable Salt (WATSS) process for converting spent uranium oxide fuel into molten salt reactor fuel.

The innovative process extracts valuable materials and radioactive byproducts from spent nuclear fuel in oxide form, including Candu, light water reactor and certain fast reactor fuels, such as mixed oxide (MOX) fuels. It accomplishes this in a single, streamlined twenty-four-hour chemical process, with a versatile pretreatment step that the company says can accommodate exotic, experimental, or advanced reactor fuels.

The extracted transuranic elements are concentrated to create molten salt fuel, while fission products are removed. This reduces the volume of the waste dramatically but also transforms spent nuclear fuel into clean, dispatchable energy, permanently eliminating long-lived transuranic elements like plutonium, Moltex says. Coupled with the company’s Stable Salt Reactor-Wasteburner (SSR-W) reactor technology, the process enables the creation of a closed fuel cycle.

Moltex states that it has now signed a Service Level Agreement with the Canadian Nuclear Safety Commission (CNSC), which “lays out a framework for engagement and discussions with the regulator to receive feedback on key topical areas such as safety, security and safeguards, to ensure that regulatory requirements are suitably taken into account at every stage of the development”.

Moltex added, “This framework will in turn allow the CNSC to facilitate engagement with the International Atomic Energy Agency to ensure that the WATSS facility and associated fuel cycle will be compatible with the application of international obligations under the treaty on the non-proliferations of nuclear weapons, and ensure best practices are incorporated into the design as early as possible.”

Last month, Moltex announced that its WATSS process had been successfully tested on spent nuclear fuel bundles from a “commercial reactor in Canada” through hot cell experiments carried out by Canadian Nuclear Laboratories (CNL) which has the only facilities in Canada equipped to handle spent nuclear fuel. The experiments demonstrated that the process can extract ninety percent of the transuranic material from spent nuclear fuel in twenty four hours, with greater efficiency over longer periods of time, the company said.

The company intends to deploy the first WATSS unit at NB Power’s Point Lepreau site in New Brunswick. Molex also plans to deploy the first SSR-W by the early to mid-2030s. The commercial-scale demonstration facility will recycle an anticipated two hundred and sixty spent nuclear fuel bundles from existing Candu pressurized heavy water reactors and create recycled fuel for the entire sixty-year operating life of one three-hundred-megawatt demonstration SSR-W. Moltex said it is now progressing with the engineering design and safety analysis of the commercial facility.

Olivier Gregoire is the Licensing Manager at Moltex. He said, “We appreciate the opportunity to get early feedback on the design from the CNSC to ensure we are designing a facility that meets the highest standards. “Early engagement minimizes the risk of late-stage additions to the design which can create needless cost increases. This engagement will streamline site specific licensing.”

Moltex Energy Limited is the U.K.-based parent company of MoltexFlex Limited and Moltex Energy Canada Inc. Earlier this month, it was announced that the company had entered administration. When a company enters administration, it means that the company is insolvent and unable to pay its debts. Offers are currently being requested to acquire the business and assets of Moltex Energy Limited and/or shares in the company’s subsidiaries. The deadline for such offers is the 7^th of May.

Molex Energy

A research team led by GE Hitachi Nuclear has successfully tested an innovative new building block made of steel-concrete composite that is purported to significantly reduce the cost of building nuclear reactor containment structures.

In 2021, the U.S. Department of Energy’s National Reactor Innovation Center (NRIC) awarded a cost-shared, multi-year project to GE Hitachi Nuclear Energy (GEH) and other stakeholders for the first project of the Advanced Construction Technology Initiative (ACTI). The purpose of this cost-shared public-private partnership is to help demonstrate several technologies that, when combined, could reduce the construction costs of building new reactors by more than ten percent and significantly lower the scheduling risks and uncertainties associated with constructing them.

As part of the initiative, GEH is working on the development of its Diaphragm Plate Steel Composite (DPSC), a modular steel-concrete composite. The DPSC design has several advantages over conventional steel concrete composite techniques, such as reinforcing concrete with two continuous steel plates connected using adjoining plates with circular concrete flow holes.

The design of the composite features reinforced concrete with two continuous steel plates, allowing for enhanced durability and flexibility. These modules can be manufactured off-site, shipped, and assembled quickly, significantly reducing labor costs and construction timelines. The modules are connected to form structural walls, floors, or mat foundation sections. DPSC test samples were recently tested at Purdue University’s Bowen Laboratory in Lafayette, Indiana.

The modules can also be manufactured to have different plate material on either side of a wall to improve meeting certain corrosion requirements in nuclear power plants.

Researchers filled the modular plates with concrete to simulate a reactor containment wall. They subjected the structure to various loading conditions to mimic real-life situations that a reactor building might experience, such as an earthquake.

Luke Voss is the program manager at the Idaho National Laboratory. He said, “The DPSC system tests at Purdue exceeded our expectations. We are very excited and enthusiastic about the use of this construction technology to help save time and money in the deployment of new nuclear reactors.”

Sean Sexstone is the Executive Vice President, Advanced Nuclear, GE Hitachi. He commented, “The successful design, fabrication and testing of DPSC modules demonstrates the potential of this advanced fabrication and construction technology to lead to cost savings and improved project schedules in the deployment of small modular reactors.”

The data collected during the demonstration will be utilized to support licensing of the modules for use in future reactor containment construction.

The National Reactor Innovation Center is currently reviewing a proposal from GEH to construct a portion of a reactor containment building using the DPSC design for the walling system to further test the technology. The demonstration would also create a digital twin of the civil structure and utilize non-destructive evaluation techniques that were developed in Phase 1 of the project.

GEH intends to implement this technology in its first four BWXR-300 small modular reactors in Darlington, Ontario, Canada. A construction license was granted to Ontario Power Generation earlier this month for this purpose.

National Reactor Innovation Center