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Production of vitrified waste at Marcoule, CEA France. Figure 3 VITRIFYING HIGH-LEVEL NUCLEAR WASTES A process similar to the one shown in the figure is now in commercial operation in Marcoule, France. The U.S. process, called vitrification, converts the liquid wastes into solid glass cylinders about 300 centimeters long and 30 centimeters in diameter. In the single-step solidification process depicted here, the liquid high-level waste is converted into a fine powder inside a calcining chamber, mixed with glass-making frit, and melted into a block of glass within the thick stainless-steel canister in which it will eventually be stored. The process is continuous: When the canister is full, the flow is switched by a diverter valve into a new canister. 54 FUSION August 1980
storage areas. Only about 4 percent of this fuel, 176 metric tons, is HLW that would be separated out during reprocessing. By the year 2000, more than 98,000 metric tons of spent fuel is expected, with about 3,920 metric tons of this as HLW. In addition, the amount of reprocessed HLW currently in the United States consists of approximately 70 million gallons from the Department of Defense and only 0.6 million gallons from the one commercial U.S. reprocessing plant, the now-closed facility at West Valley, New York. Reprocessing fuel and separating out the waste will reduce by more than 25 times the quantity of waste material that must be disposed of. This, combined with the reduced radioactivity and heat generation, is an additional important advantage of a fuel reprocessing system. Storage Technology There are two technical problems in handling and storing radioactive nuclear fission waste material. The first is the radioactivity from the decay of unstable elements by either alpha or beta particles and gamma rays. This radiation is dangerous to human beings from external or internal sources; therefore, it must be kept isolated from the biosphere for as long as the activity remains high. The second problem is that radioactive decay produces energy in the orm of heat, and this heat must be dissipated for as long a time period required in order to keep material temperatures below certain design limits. Both the shielding ind the heat removal must be resolved simultaneously, The most technically developed process for high-level waste disposal 5 to store the waste in concentrated liquid form at ground level for a cooling period of 5 to 10 years. At that point it can be solidified into small canisters and buried in a de^p underground location in thick, stable rock-salt strata. Liquid storage of the waste and eventual solidification al will take place on the reprocessing plant site (for examf le, the Barnwell facility) in a completely controlled and monitored environment. For years storage of liquid wastes has been a state-of-the-art technology. In fact, the Depar ment of Defense has used storage in this form since the early 1940s and has highly developed the technique (Figure 2). This propose I solidification process uses an automated system that cor verts the liquid waste by evaporation to a fine powder, rrixes it with a fine glassy frit material, and converts it to a olid glassy cylinder by heating the mixture to melting and hen solidifying it (Figure 3). This is already a developed te< hnology and is now used commercially in France, as sho vn in the photograph. The solid waste What the Experts Say About Radioactive Nuclear Waste American Institute of Chemical Engineers, Nuclear Engineering Division policy statement, 1977: ". . . Satisfactory techniques exist today for safe radioactive materials handling, the reprocessing of spent fuel, and solidification of high-level wastes. . . . Several candidate options for ultimate disposal are ready for demonstration. These techniques are being improved rapidly as the technology continues to advance. Other countries have recognized this, and have overtaken the United States in the rate of introduction of efficient nuclear power plants and waste treatment techniques. . . . The Institute believes that actual demonstration of radioactive waste disposal is sufficiently urgent that it is far better to proceed with an acceptable solution than to delay by looking for unnecessary minor benefits which might possibly emerge from alternatives. . . ." wastes disposal at the earliest possible time, as a part of a national nuclear waste disposal program. . . ." American Physical Society, study on Nuclear Fuel Cycles and Waste Management, published in Reviews of Modern Physics, 1978: ". . . The technology exists for recoverable storage of the spent fuel with minimal deterioration to preserve the associated resources, but full-scale demonstration is required before use. . . . "Effective long-term isolation for spent fuel, high-level or transuranic waste can be achieved by geologic emplacement. A waste repository can be developed in accord with appropriate site selection criteria that would ensure low probability that erosion, volcanism, meteorite impact and other natural events could breach the repository. . . ." Association for Cooperation in Engineering, Coordinating Committee on Energy (This association represents 24 major engineering professional societies in the United States, with a combined membership of more than 700,000 engineers.), 1980: Continued on page 56 August 198( FUSION 55
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Page 11 and 12: FEF DIRECTOR SPEAKS AT WEST POINT F
Page 13 and 14: Americans, any links between drugs
Page 15 and 16: News media with eyes trained on Was
Page 17 and 18: FEMA Describes Its Master Plans Reo
Page 19 and 20: Special Report Just when some of th
Page 21 and 22: Teaching About Population: Since fa
Page 23 and 24: Washington Austerity-Minded Congres
Page 25 and 26: McCormack Readies Fight For Fusion
Page 27 and 28: Four men who did not subscribe to E
Page 30: The panel unanimously proposed that
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Page 38 and 39: How France Took the IMAGINE A COUNT
Page 40 and 41: and clearsightedness. The decision
Page 42 and 43: called Sofidif (60 percent CEA, 40
Page 44 and 45: the nation-state and scientific-tec
Page 46 and 47: "I do not think there exists anywhe
Page 48 and 49: Algeria, France exploded its first
Page 50 and 51: The Fifth Plan, covering the period
Page 52 and 53: Figure 1 COMPARISON OF MATERIAL COM
Page 54 and 55: Figure 2 DEEP UNDERGROUND NUCLEAR W
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Page 60 and 61: Photo by Carlos de Hoyos/NSIPS Team
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Page 64 and 65: Photo courtesy of Indian Embassy "j
Page 66 and 67: EQUIVALENT MEASURES IN THERMODYNAMI
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