Metal fuel development

Koyama, T., Sakamura, Y., Ogata, T., and Kobayashi, H. (2009) Pyroprocess and metal fuel development for closing actinide fuel cycle with reduced waste burden. Proceedings of GLOBAL 2009, Paris, France, September 2009, Paper 9247. 

Lee, C.B., et al., 2013. Status of SFR metal fuel development. In International Conference on Fast Reactors and Related Fuel Cycles (FR13), Paris, France. 

Another reactor that was approved for development was a land-based prototype submarine propulsion reactor. Westinghouse Electric Corp. designed this pressurized water reactor, using data collected by Argonne. Built at NRTS, the reactor used enriched uranium, the metal fuel in the form of plates. A similar reactor was installed in the submarine l autilus. 

A more recently developed pyrometaHurgical process is that of the proposed integral fast reactor, which would use metallic fuel (U—Pu—Zr alloy) and a molten salt electrorefiner as follows ... 

Small arms ammo can be so severely affected by moisture that a special indicating lacquer was developed for 20mm rounds which changes color from grey to black on w exposure (Ref 59) Effect of Moisture on Pyrotechnics Pyrot formulations usually contain finely powdered metal fuels such as Mg, Al, Fe, Cu, etc, all of which can react with moisture to yield H2. This effect has been dubbed gassing in pyrot circles, and is the major problem associated with the storage of hermetically sealed ammo of this... 

Military propellants are based on relatively powerful oxidisers and fuels of high calorihc value in order to develop an improved thrust or impulse. Thus the most commonly-used oxidisers are potassium perchlorate, ammonium perchlorate or more esoteric compounds such as hydrazinium nitroformate. Metallic fuels include aluminium, magnesium and beryllium, while binders are mainly hydrocarbons such as polybutadiene, polyisobutylene, polyurethane or poly(vinyl chloride) (PVC) as presented in Table 3.2. 

Powdered metal flames have been extensively studied at Temple University. Conway and Grosse (20G) report the development of a torch using powdered metal as a fuel. A history of past work in this field is included. For successful results powders less than 200-mesh must be used. Branstetter, Lord, and Gerstein (16G) have used metal fuels, both powders and wire, in a 2-inch-diameter ram-jet-type combustor. 

With the use of fuels that produced hotter flames, earlier flame photometers became useful for analyzing elements beyond the alkali and alkaline earth metals. The development of atomic absorption spectrophotometers in the late 1960s provided the analytical chemist with a better tool for many of these applications. Later developments in high-temperature flame photometry narrowed the analytical applications of low-temperature flame photometry even further. The utility of the flame photometer to the clinical chemist, however, was not diminished until the development... 

The three types of nonaqueous processes on which most development work has been done are (1) pyrometallurgical processes, involving high-temperature processing of metallic fuels (2) pyrochemical processes, involving high-temperature processing of oxide or carbide fuels and (3) fluoride volatility processes, in which elements in fuel are converted to fluorides, which are then separated by fractional distillation. 

Fractional crystallization. Volatile metals with much lower boiling points than uranium, such as magnesium (1103°C), zinc (906°C), and cadmium (767°C), have been extensively studied as solvents for separating constituents of irradiated metal fuel by fractional crystallization, followed by evaporation of the solvent metal from the separated fractions. For example, in liquid magnesium, the solubility of plutonium or thorium is high, but uranium is very low. A process of this type was developed at Argonne National Laboratory [P6] for concentrating plutonium in the uranium metal blanket of a breeder reactor from 1 percent to 40 percent. 

Brookhaven made engineering-scale studies of a process in which uranium metal fuel was dissolved in a liquid interhalogen compound such as BrFa. The reaction was difficult to control work was terminated after an explosion [B18], Brookhaven later developed the Nitrofluor process [B19], in which fuel was converted to UF4 and PuFs by a liquid mixture of HF and oxides of nitrogen. After dissolution, UF4 was converted to UFg by BrFa and distilled off. Finally, PuFs was converted to PuF by fluorine and distilled off. 

Electrolytic dissolution in nitric acid has been used at the Savannah River [B22] and Idaho Qiemical Processing plants [AlO, All] to dissolve a wide variety of fuels and cladding materials, including uranium alloys, stainless steel, aluminum, zircaloy, and nichrome. The electrolytic dissolver developed by du Pont [B22], pictured in Fig. 10.4, uses niobium anodes and cathodes, with the former coated with 0.25 mm of platinum to prevent anodic corrosion. Metallic fuel to be dissolved is held in an alundum insulating frame supported by a niobium basket placed between anode and cathode and electrically insulated from them. Fuel surfaces facing the cathode undergo anodic dissolution in a reaction such as... 

Fuel systems for LMRs are well developed. Oxide, carbide, nitride or metal fuel have been demonstrated and provide many options for addressing the long life requirement for the fuel. Metal fuels, in particular, offer promise of improved safety characteristics. 

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