National Nuclear Security Administration– The MOX Project
In 2000, the United States and Russia signed a bilateral agreement stipulating that each country would commit to eliminating 34 metric tons of surplus military plutonium produced during the Cold War by recycling it as fuel for civil nuclear applications. The U.S. Department of Energy decided on a program for the long-term disposition of the weapons-grade plutonium by converting the materials to nuclear fuel for use in commercial reactors. The resulting used fuel is rendered useless for weapons purposes.
The Department of Energy’s National Nuclear Security Administration signed an agreement with an AREVA and SHAW joint venture for the design, construction, and operation of this facility, MOX Fuel Fabrication Facility (MFFF).
MOX Fuel Fabrication Facility
Located on the Savannah River Site near Aiken, South Carolina, the MOX (mixed oxide) Fuel Fabrication facility is a major component in the United States program to rid itself of excess weapons-grade plutonium.
The MFFF will take excess weapons-grade plutonium, remove its impurities, and mix it with uranium oxide to form MOX fuel pellets to be inserted in to reactor fuel assemblies. These assemblies will then be sent to commercial nuclear power plants where they will be used in nuclear reactors to generate electricity.
The design for the MOX facility based on AREVA’s recycling technology that has been used successfully for almost two decades. AREVA’s MELOX and La Hague facilities in France currently supply MOX fuel to over 30 nuclear reactors world wide, and the expertise and know-how from these facilities will provide this basis for the MFFF technology and design.
Construction of the MOX Facility
The MFFF consists of two major sections, the Aqueous Polishing section and the MOX section. In the seven-layer aqueous polishing section, weapon-grade material is cleaned and purified, before it is sent to the MOX section. The MOX area is where the fabrication of the fuel takes place. This involves blending polished plutonium and depleted uranium to form the fuel pellets which are hardened, sized and loaded into fuel rods. The rods are then used to build fuel assemblies of the MOX fuel to be shipped to commercial utilities.
The Nuclear Regulatory Commission (NRC) will license and oversee the facility. AREVA’s design is being customized to ensure that the facility meets all U.S. federal safety and security requirements. It will also be a hardened facility, similar to a nuclear reactor. Security will be equal to the security measures currently in place at the Savannah Rive Site. A Perimeter Intrusion Detection and Assessment System will encircle the facility for additional protection.
When operational, the facility will be capable of turning 3.5 metric tons of weapon-grade plutonium into MOX fuel assemblies annually. The facility will be licensed for 20 years, with operations expected to continue into the 2030s.
Preliminary numbers for construction of the 600,000 ft2 facility (including support facilities) indicate the use of over 170,000 yd3 of concrete, 35,000 tons of reinforcing steel, 23,000 instruments, 1000 tons of Heating Vents and Air conditioning 500,000 linear feet of conduit, 47,000 linear feet of cable tray, 3,000,000 linear feet of power and control cable, and 80 miles of piping.
What is MOX fuel?
Mixed Oxide (MOX) fuel is a mixture of approximately 95 percent uranium oxide and 5 percent plutonium oxide. The MOX Fuel Fabrication Facility will blend the 5 percent of plutonium oxide (PuO2) with the 95% of uranium oxide (UO2) powder to make a mixed oxide powder.
This powder is milled to ensure uniform distribution of the plutonium, and to adjust the particle size of the MOX powder. The MOX powder is made into small pellets about the size of a pencil eraser. These pellets are pressed into shape, baked at high temperatures, and ground down to approximately 1/3 inch in diameter and 4/10 inch in length, the required dimensions of reactor fuel rods.
The finished pellets are loaded into fuel rods through an open end. An end plug is then inserted into the open end of the fuel rod and the rod is welded shut. The fuel rods are inspected, decontaminated, and bundled together to form fuel assemblies. Each fuel assembly is then prepared for transportation to a commercial nuclear power plant, where it is used as fuel in a nuclear power reactor.
Simply put, Shaw AREVA MOX Services, LLC, takes nuclear weapons-grade plutonium and reduces it down to usable fuel to power America.