Search citation statements
Paper Sections
Citation Types
Year Published
Publication Types
Relationship
Authors
Journals
The necessity for and ways to improve the technology for reprocessing liquid radioactive wastes from nuclear power generation are substantiated taking account of the chemical contaminants (petroleum products and products of corrosion). As a general solution, it is proposed that autonomous modular purification facilities, operating on the principle of combining baromembrane and sorption methods, be developed. The basic scheme of the proposed technology and the construction of the purification facilities are described. The results of industrial tests performed on a tanker for collecting liquid wastes from the Pacific Ocean fleet are presented. It is shown that purification to the level of allowed discharges into the sea is possible and that the radioactive concentrates formed can be solidified by cementation.The general concept of centralized collection and reprocessing of liquid radioactive wastes at the sites of the bases of the nuclear-powered submarine and ice-breaker fleet has proved to be untenable, first and foremost, because it is impossible to follow tractably the overall trend of increasingly stringent radiation-safety requirements. Special vessels (Amur and Pinega) have been developed to collect and reprocess liquid wastes. Their technological operating scheme provided for separate receiving and reprocessing of wastes (purification, concentration of radionuclides, and conditioning of wastes) depending on the form and degree of salinity [1].Water with salt concentration above 1000 mg/liter must be reprocessed using a coagulation-precipitation scheme. Suspensions are removed from water with concentration less than 100 mg/liter using filters and additional purification on ion-exchange filters. The coagulation pulps formed and the spent ion-exchange resins must be incorporated in bitumen compounds for subsequent disposal. Reprocessing using this scheme lowered the concentration of radionuclides in the waters purified to 3.7·10 5 Bq/liter, which met the standards for discharge into the sea in the 1980s, when such facilities were developed. The leaching of radionuclides should be less than 1·10 -4 g/(cm 2 ·day), which at that time was considered to be adequate for disposal at the bottom of the sea.The more stringent requirements for the quality of discharge water, the need for purification to admissable norms for discharge into the sea according to the requirements of first NRB-76/87 and then NRB-99 (to 1.1·10 2 Bq/liter with respect to 137 Cs, to 50 Bq/liter with respect to 90 Sr, and to 4.1·10 2 Bq/liter with respect to 60 Co [2]), and the expansion of the list of wastes which need to be reprocessed required the development of new and more efficient technological schemes. In addition, the technology had to be re-examined from the standpoint of the final stage of solidification of the wastes, since bituminization had to be rejected because of the fire-and explosion hazard of the process and the flammability of the solidified products, which according to modern requirements must be buried on dry land. Conseque...
The necessity for and ways to improve the technology for reprocessing liquid radioactive wastes from nuclear power generation are substantiated taking account of the chemical contaminants (petroleum products and products of corrosion). As a general solution, it is proposed that autonomous modular purification facilities, operating on the principle of combining baromembrane and sorption methods, be developed. The basic scheme of the proposed technology and the construction of the purification facilities are described. The results of industrial tests performed on a tanker for collecting liquid wastes from the Pacific Ocean fleet are presented. It is shown that purification to the level of allowed discharges into the sea is possible and that the radioactive concentrates formed can be solidified by cementation.The general concept of centralized collection and reprocessing of liquid radioactive wastes at the sites of the bases of the nuclear-powered submarine and ice-breaker fleet has proved to be untenable, first and foremost, because it is impossible to follow tractably the overall trend of increasingly stringent radiation-safety requirements. Special vessels (Amur and Pinega) have been developed to collect and reprocess liquid wastes. Their technological operating scheme provided for separate receiving and reprocessing of wastes (purification, concentration of radionuclides, and conditioning of wastes) depending on the form and degree of salinity [1].Water with salt concentration above 1000 mg/liter must be reprocessed using a coagulation-precipitation scheme. Suspensions are removed from water with concentration less than 100 mg/liter using filters and additional purification on ion-exchange filters. The coagulation pulps formed and the spent ion-exchange resins must be incorporated in bitumen compounds for subsequent disposal. Reprocessing using this scheme lowered the concentration of radionuclides in the waters purified to 3.7·10 5 Bq/liter, which met the standards for discharge into the sea in the 1980s, when such facilities were developed. The leaching of radionuclides should be less than 1·10 -4 g/(cm 2 ·day), which at that time was considered to be adequate for disposal at the bottom of the sea.The more stringent requirements for the quality of discharge water, the need for purification to admissable norms for discharge into the sea according to the requirements of first NRB-76/87 and then NRB-99 (to 1.1·10 2 Bq/liter with respect to 137 Cs, to 50 Bq/liter with respect to 90 Sr, and to 4.1·10 2 Bq/liter with respect to 60 Co [2]), and the expansion of the list of wastes which need to be reprocessed required the development of new and more efficient technological schemes. In addition, the technology had to be re-examined from the standpoint of the final stage of solidification of the wastes, since bituminization had to be rejected because of the fire-and explosion hazard of the process and the flammability of the solidified products, which according to modern requirements must be buried on dry land. Conseque...
The paper is devoted to the solidification of radioactive sea-salt concentrates in a modular cementing facility yielding 200-liter cement blocks. The solidified products with Cambrian clay added as a sorption aid satisfy with respect to the mechanical strength and radionuclide leaching the domestic and foreign requirements for safe storage in standard and very simple disposal sites.Liquid radioactive wastes which often contain sea salts in substantial amounts are formed during the operation of propulsion nuclear power systems (NPSs). Floating facilities for reprocessing radioactive waters (the special tankers Amur in the Northern fleet and Pinega in the Pacific Ocean Fleet) were provided for reprocessing radioactive water. The plan was to incorporate the radioactive concentrates into bitumen compounds using the proposed technology [1]. However, because the bituminization process presents a danger of fire and explosion and the solidified products are plastic and combustible (the flash point is below 300°C) it is being replaced by the technologically simpler, safer, and less energy intensive cementing process.Cementing for solidifying radioactive concentrates by simple mixing of the components makes it possible to obtain strong and noncombustible products which retain their integrity even in shipping accidents. For example, cement blocks do not lose their shape after standing for 30 min at 800°C, and since their mechanical strength is 10 MPa they remain whole when dropped from a height of 9 m [2]. However, cement compounds do not fix radionuclides nearly as strongly as bitumen compounds.Sodium chloride (NaCl), which determines the salt content of sea waters, does not interact chemically with bitumen.
No abstract
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.