![]() ![]() Costs of storage of the Purex and Thorex wastes together in the same facility ranged from 1.5 x 10/sup -3/ mill/kwh/sub e/ for 1-yr storage to 4.8 x 10/sup -3/ mill/kwh/sub e/ for 10-yr storage for the calcined acid wastes and from 1.8 x 10/sup -3/ to 6.3 x 10/sup -3/ wastes at time of storage was not a very significant factor, the costs for storage of 10-yr-decayed wastes being only 10 to 15% less than those for storage of the same wastes aged 120 days. Costs ranged from 1.5 x 10/sup -3/ mill/kwh, for 1-yr storage of calcined 10-yr-old acid Purex waste to 18 x 10/sup -3/ mill/kwh/sub e/ for 30-yr storage of calcined, reacified 120-day- old Thorex wastes. Costs for interim storage times from 1 to 30 yr were computed for wastes decayed 120 days and 1, 3, and 10 yr at time of initial storage. Consideration was given also to storage (in the same facilities) of the combinations acid Purex-acid Thorex and reacified Purex-reacidified Thorex wastes. Separate facilities where designed for the storage of the calcined wastes more » in the acid and reacified forms, and for the Thorex waste made into a glass. The wastes were assumed to have been solidified following their production in a plant proccessed 1500 metric tons per year of uranium converter fuel it a burnup of 10,000 Mwd/ton and 270 tons/yr of thorium converter fuel at 20,000 Mwd/ton. The costs of interim storage of solidified Purex and Thorex wastes in water-filled canals were estimated as the third part of a study to evaluate, from the standpoint of econoNonemics and hazards, the various steps leading to and including the permanent disposal of highly radioactive liquid and solid wastes. For waste storage times of 0.5 to 30 years, costs ranged from 2.2 x 10/sup -3/ to 9.5 x 10/sup -3/ mill/kwh/sub e/ for acid wastes and from 1.7 x 10/sup -3/ to 5.1 x 10/sup -3/ mill/kwh/sub e/ for neutralized wastes. With interim storage time defined as filling time plus full time, tank costs were minimum when full time was 40 to 70% of the interim storage time, using present worth considerations. The operating cycle of each tank was assumed to consist of equal filling and emptying periods plus a full (or dead) period. Tanks of Savannah River design were assumed, with stainless steel construction for acid wastes and mild more » steel construction for neutralized wastes. A 6- ton/day plant was assumed, processing 1500 tons/year of uranium converter fuel at a burnup of 10,000 Mwd/ton and 270 tons/year of thorium converter fuel at a burnup of 20,000 Mwd/ton. « lessĪs the first part of a study to evaluate the economics of the various steps leading to and including the permanent disposal of high-activity liquid and solid radioactive waste, costs of interim liquid storage of acid and alkaline Purex and Thorex wastes were estimated for storage times of 0.5 to 30 years. Such studies would provide guidelines for extrapolating experimental results obtained with the polybutene model fluid to molten glasses with somewhat different fluid properties. It is recommended that future work be done to substantiate and further develop the proposed model of the dispersion mechanism, and to determine the effect of viscosity on foam formation. Fluid temperature had a large effect on viscosity, but the effect was not investigated fully. No trend was observed between the foam viscosity and the percent gas loading. It was found that up to 23 percent gas loading, the foam exhibits Newtonian characteristics and that the foam viscosity was greater than that of pure polybutene at the same temperature. ![]() The viscosity of the foam at various gas loadings was measured. A model based on bubble formation rate as a function of power input and gas loading was postulated to characterize the dispersion mechanism. The maximum gas loading obtained was 23 percent at 6900 rpm with a liquid flow rate of 165 ml/min and input power of approximately 190 w. An increase in input power was found to increase gas loading, but indications were that maximum gas loading at zero liquid flow rate was independent of input power. It was found that at a constant input power to the impeller motor of 155 w, impeller blade more » pitch had no significant effect on gas loading. ![]() The effects of input power, impeller blade pitch and liquid flow rate on gas loading and viscosity were studied. (Argon and polybutene were chosen as model fluids to simulate the dispersion of radioactive krypton and xenon in molten glass.) The experimental apparatus used was a cylindrical lucite chamber equipped with a variable speed impeller, gas and polybutene inlets, foam withdrawal ports, and pressure and temperature measurement capability. This study was conducted to further investigate parameters affecting the dispersion of argon in polybutene. ![]()
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