Lucie 1 St. Cook 1 D. Hatch 1 Edwin I.
Hatch 2 Joseph M. Farley 1 Joseph M. As was stated in Section A. It is unlikely that reactors in these categories would be clearing scrap metal in the foreseeable future. For the purpose of the present analysis, the three non-light water reactors are treated as if they were BWRs.
The last column lists the date that significant quantities of scrap metal would be released from these reactors.
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B-4 B B-9 B B B Smelters in B B-l5. Table B-l. Presumably this is contaminated and suspect contaminated material. The DOE estimate is in reasonable agreement with the quantities tabulated above.
I Scrap Metal Inventory Chapter 4 of the present report summarizes information on the potential quantities of aluminum scrap available for recycle from DOE and commercial facilities. However, there is no available information as to the portion of the aluminum that may be contaminated and the radionuclide composition of the contamination. Most of the aluminum from commercial nuclear power plants is expected to be in gratings, switch gear, and component housings. It is proposed in Section 4. The authors of this appendix have generally chosen not to convert the units to a consistent system but rather have chosen to quote information from the various sources in the original units.
When the cited information is distilled into scenarios for modeling doses and risks, consistent units are used. According to Table A, the total of amount of aluminum in all commercial nuclear power reactors is about 1, metric tons t. Only a fraction of this inventory is expected to be significantly contaminated and not all of the contaminated inventory may be potentially suitable for recycling.
Applying these factors to the entire U. For currently operating reactors, it is assumed that the scrap will be available ten years after the expiration of the current operating license. The methodology for assessing formerly licensed reactors is presented in Appendix A-l. Using this decommissioning schedule, annual availability of scrap can be established as shown in Table B-2 based on Appendix A, Table A It can be seen that 28 t of aluminum would be released from commercial nuclear power plants in the peak year: Based on a survey of DOE data, it is estimated that 2, t of contaminated, potentially releasable aluminum were in inventory at the end of see Table and that 33, t of contaminated aluminum will be generated from future decommissioning activities, resulting in a total of 36, t of contaminated aluminum see Table 3.
Decommissioning schedules for the diffusion plants are assumed to be as follows see Section 4. They further assumed that two PWRs would be decommissioned each year, resulting in 40 t of contaminated aluminum available for recycle annually. This value appears to be conservative i. Table B In January , the Secretary of Energy issued a moratorium on the Department's release of volumetrically contaminated metals "pending a decision by the On July 13, , the Secretary of Energy issued a memorandum This suspension will remain in effect until improvements in DOE release criteria and information management have been developed and implemented" Michaels Based on these DOE policy decisions, it is assumed in this report that releases of scrap metal from DOE facilities will not begin until Some information as to the breakdown by location of aluminum scrap in the DOE inventory can be found in U.
DOE , vol. These data are reproduced in Table B Since most of this material is not specified to be clean or contaminated in the source document, the same methodology used in Chapter 4 is applied here. Table indicates that are "clean," contaminated, and 5, "unspecified. Furthermore, the quantity reported for each site was multiplied by a scaling factor of 1.
The availability of potentially recyclable aluminum scrap from DOE facilities is summarized in Table B Clearly, any aluminum scrap recycling scenarios will be dominated by scrap from DOE facilities rather than from nuclear power plants. The maximum amount of scrap available in any year is t, which is the expected inventory by the year The largest source of this material is the K plant.
The radioactive contamination of these materials is attributed to a limited suite of radionuclides. The predominant contaminants are isotopes of uranium and their radioactive progenies. Smaller amounts of Tc and trace quantities of Pu and Np may also be present. Indicated contamination levels for aluminum scrap metal items in inventory at the diffusion plants are as follows U. Recent studies have shown that, for the cast aluminum compressor blades used in the diffusion plants, much of the contamination is internal, caused by UF6 entering surface-connected voids Compere et al.
The industry's recycling operations, commonly referred to as the "secondary aluminum industry," use purchased scrap as "raw" material. Purchased aluminum scrap is classified as "new" manufacturing scrap and "old" scrap discarded aluminum products. In , metal recovered from both new and old scrap reached an historic high of approximately 3. Geological Survey from its "Aluminum Scrap" survey of 90 U.
The predominant type of purchased scrap was aluminum used beverage container UBC scrap, accounting for more than one-half of the old scrap consumed. Aluminum recovered from scrap has increased tenfold since The recovery of aluminum from old scrap has shown an even more rapid expansion over the same period of time. Increased costs for energy and growing concerns over waste management have provided the impetus for increased recycling rates. Improvements in recycling technologies and changes in the end-use consumption patterns have also contributed to the increase in aluminum scrap recovery.
Obsolete industrial products, such as transmission cables, aircraft, and other similar items; outdated inventory materials; production overruns; out-of-specification products; etc. Aluminum alloys are divided into two distinct categories according to how they are formed: cast alloys and wrought alloys. Controlling the composition of aluminum recovered from scrap is essential to producing marketable secondary alloys. Cast alloys are those specially formulated to flow into a sand or permanent mold, to be die cast, or to be cast by any other process into the final form for end use.
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Wrought alloys are alloys that have been mechanically worked after casting. The "wrought" category is broad, since aluminum can be formed by virtually every known process. Wrought forms include sheet and plate, foil, extrusions, bar and rod, wire, forgings, and tubing. The application or end product use of the aluminum determines which of these two major alloy categories is employed for the product.
Application requirements determine the specific alloying elements and proportions of each element present in the product. The mix of alloys recovered in aluminum scrap at a given time varies depending on 1 patterns of use and discard of these products, 2 the collection systems that act to intercept the discarded waste materials, 3 the separation efficiency with regard to control of scrap shape and size, and 4 degree of processing required to remove certain contaminants.
New industrial scrap, assuming proper segregation and identification, can be melted with minimal corrective additions. The processing of post consumer scrap, on the other hand, is much more difficult to predict because the scrap has a variable composition. The primary producers recover aluminum from bauxite ore via an electrolytic process in cells or "pots. The primary aluminum production plants do not recycle any outside material; however, an integrated aluminum company will utilize scrap aluminum feed in other facilities, separate from the primary pot-line plant.
In general, the primary producers practice recycle, mostly for UBC's, in large reverberatory smelters. They also recycle "new" scrap from their customers in very large smelters, and return the particular product to their customers. Such plants are not suitable for a feed scrap stream having many different alloy compositions since, if the smelter produced an "off-spec" material, the rework of very large smelter volumes makes such an event very costly.
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Primary producers consumed 2,, t of old and new scrap in , as summarized in Table B Includes municipal waste and fragmented auto shredder scrap. In , about In , secondary aluminum smelters consumed 1,, t of purchased new and old aluminum scrap and recovered 1,, t of metal containing , t of aluminum Plunkert The sources of this scrap are summarized in Table B Table B-5 U. EPA Another source states that the North American industry involves 46 companies with 81 smelting operations Novell! A major product of the secondary smelters is feed stock for production of aluminum castings.
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Aluminum casting alloys are tolerant to a variety of alloying elements, so mixed scrap can be used. If the scrap is carefully segregated, wrought alloys with less tolerance to impurities can be produced.
In practice, secondary smelter sourcing, processing, and marketing can be highly complex. Scrap materials recycled included dross, used beverage cans, post- consumer and commercial scrap, and new scrap from manufacture of cans and other products. About one-half of the material was from the beverage can and packaging industry; the balance was from transportation and construction market sectors.
The balance was supplied to the steel industry and miscellaneous customers. In contrast, Wabash Alloys, which has five U. A flow diagram for typical secondary smelter processing is shown in Figure B-l.