Dioxide pellets

Modop [Mobil Oil Direct Oxidation Process] A process for removing residual sulfur-containing gases from the tail gas from the Claus process. The catalyst is titanium dioxide pelletized with calcium sulfate. Developed in the 1980s by Rhone-Poulenc, Procatalyse, and Mobil Oil. Three plants were operating in Germany in 1995 and one in the United States. European Patents 60,742 78,690. 

T0141 Carbon Dioxide Pellet Surface Cleaning—General T0142 Carlo Environmental Technologies, Inc., Medium-Temperature Thermal Desorption (MTTD)... 

T0134 CAE Alpheus, Inc., Carbon Dioxide Blasting T0139 Cancrete Environmental Solutions, Inc., Depocrete T0I4I Carbon Dioxide Pellet Surface Cleaning—General... 

Carbon Dioxide Pellet Surface Cleaning — General... 

In a 1992 report for the U.S. Department of Energy (DOE) facility at Rocky Flats, it was estimated that the cost of operating the Alpheus carbon dioxide pellet system in a mixed waste removal application would be approximately 297 per hour. It was estimated that if the system was able to clean 100 lb of material per hour, the cost of cleaning a standard 5000 lb of material would be 14,850. This would be less than the cost of shipping the material for cleaning at another facility using conventional methods (D150871, p. 4). 

ASTM C833-01 Standard specification for sintered (uranium-plutonium) dioxide pellets. 

Tubular reactor containing packed bed was used in a noncirculating mode to study the photocatalytic degradation of TCE and tetra-chloroethylene (Yamazaki-Nishida et al., 1996). The packed bed contained titanium dioxide pellets (1 mm in diameter), prepared by sol-gel and fired at 200-500°C. An inverse correlation between the firing temperature of the pellets and the formation of undesirable chlorinated compounds such as chloroform and carbon tetrachloride was foimd. 

The apparatus is set up as in Fig. 14.5 and a rapid flow of ammonia is used to flush out the system. A small volume of acetone (or ethanol) is poured into the condenser, and solid carbon dioxide pellets arc added (very slowly at first) until the condenser is nearly full. The ammonia will begin to condense, and when the required volume is obtained, the ammonia flow is shut off and the gas inlet replaced by a septum or stopper. If undried impure ammonia will suffice, and often it will, then the reaction is carried out as normal. A cooling bath can be added if a long reaction time is anticipated, or if a temperature below -33 C is required (see Chapter 9). 

ZIRCALOYSTROCTOfiAL END PLATE ZIRCALOY END CAP ZIRCALOY BEARING PADS URANIUM DIOXIDE PELLETS ZIRCALOY FUEL SHEATH ZIRCALOY SPACERS GRAPHITE COATING... 

Costa and Smith " studied the hydrofiuorination of nonporous uranium dioxide pellets under conditions where external mass transfer resistance was negligible. The global rate was initially controlled by the surface chemical reaction resistance, but switched to product layer diffusion as the reaction progressed and the product layer thickness increased. 

Gas-solid heterogeneous reactions may be noncatalytic. An example is the hydrofluorination of uranium dioxide pellets referred to in Sec. 7-1. Since one reactant is in the solid phase and is consumed, the rate of reaction varies with time. Hence such processes are basically transient, in comparison with the steady-state operation of gas-solid catalytic reactors. The process for smelting ores such as zinc sulfide,... 

Example 8-6 The mercury-penetration data given in Table 8-4 were obtained on a 0.624-g sample of a uranium dioxide pellet formed by sintering particles at 1000°C for 2 hr. Since the particles were nonporous, the void space was entirely between the... 

Table 8-4 Mercury porosimeter data for uranium dioxide pellet (mass of sample 0.624 g)...

ZnCALOY BEARING PADS CANLUB QRAPHrrE INTERUYER URANIUM DIOXIDE PELLETS... 

Zircaloy bearing pads Canlub graphite interlayer Uranium dioxide pellets... 

Surface area by nitrogen absorption method Total gas in reactor-grade uranium dioxide pellets Thorium and rare earth elements by spectroscopy Hydrogen by inert gas fusion... 

C922. (2008). Standard specifications for sintered gadolinium oxide-uranium dioxide pellets. West Conshohocken, PA ASTM. 

Small thermal-spectmm reactors of long refuelling interval using uranium dioxide pellet type fuel derate their core power density (kW(th)/litre) and specific power (kW(th)/kg compared to commercial LWRs, thereby increasing fissile specific inventory ... 

Uranium dioxide pellets of 7.6 mm diameter are used as a fuel the uranium enrichment is up to 5% by weight (maximum licensed enrichment). 

As it follows from Fig. X-5, the evolution of this accident for the VKR-MT and a WER-1000 is essentially different. In VVER-1000, the temperature of zirconium claddings increases promptly due to high-temperature heat accumulated in the uranium dioxide pellets and due to heat removal deterioration. The VKR-MT core is practically not heated in the first seconds of the accident process, as the temperatures of micro fuel elements and the coolant in normal operation are different by a few degrees only. Later on, the temperature of micro fuel elements slightly increases due to residual heat up until the start-up of the emergency core cooling system (ECCS) operation. The accident is localized after the core is filled with the ECCS water. As the temperature of micro fuel elements is well below 1500°C, the release of radioactivity to the containment remains at the level of 10. ... 

---