Radioactive waste streams

Researchers claim that lonsiv TIE-96 can remove 99.9% of the plutonium, strontium, and cesium from waste solutions, allowing for wastes to be divided into separate low-level and high-level radioactive waste streams, where they can be safely and efficiently processed for disposal. 

Committee on the Management of Certain Radioactive Waste Streams Stored in Tanks at Three Department of Energy Sites National Research Council. 2006. Tank waste retrieval, processing, and on-site disposal at three Department of Energy sites Final Report. National Academy of Sciences. 

Over the years, several technologies, inspired by differing ideas, have been developed to treat radioactive waste streams. Some of them are based on efficient separation methods that remove radioactive contaminants from the waste streams to reduce radiological... 

Based on the half-life and specific activity of commonly occurring isotopes in radioactive waste streams given in Table 17.2, each disposal site or repository of the treated waste has developed waste acceptance criteria (WAC). The WACs require that the treated waste pass certain test criteria, which vary from site to site depending on the nature of the waste stored. In a number of case studies discussed in this chapter, we will use these WACs to demonstrate compliance of the CBPC waste form. 

Case Studies in Stabiiization of Radioactive Waste Streams... 

CASE STUDIES IN STABILIZATION OF RADIOACTIVE WASTE STREAMS... 

Unlike the case for hazardous waste streams using phosphates, the literature on stabilization of radioactive waste streams using CBPC processes is mainly limited to work... 

In contrast to the two studies mentioned above, the work at ANL has been mainly in demonstrating treatment of a range of radioactive waste streams (both simulated and actual) from the US DOE complex in the Ceramicrete matrix. The reader is referred to Ref. [21] and additional references therein. In this section, we provide an overview in the form of case studies. Table 17.5 lists acceptance criteria and the corresponding case studies selected to demonstrate compliance by the Ceramicrete waste forms with those criteria. 

The various case studies discussed in this paper demonstrate that CBPCs are a very versatile material for the stabilization of hazardous and radioactive waste streams. CBPCs chemically immobilize and microencapsulate the contaminants, and reduce leaching to levels that meet WAC at DOE sites. They are also suitable for the macroencapsulation of various contaminated objects. 

As a radiochemist, I would like to note the great significance of chemically bonded ceramics for high level waste (HLW) treatment. It is well known that for safe storage, transportation, and disposal of radioactive waste streams, it is necessary to convert them to hardened forms. Therefore, the search for and development of a new solid matrix for immobilization of HLW forms are important, indeed. 

We, at the Verandsky Instimte of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, have recognized this and have already initiated research on these materials for stabilization of some difficult high activity radioactive waste streams. The simple concept of forming these ceramics by acid-base reaction, the resulting room-temperature fabrication processes, and the superior properties of the product ceramics, all presented in this book, are helping us to solve some difficult... 

The last five chapters of the book are devoted to major applications of CBPCs. Chapter 14 covers CBPC matrix composites that are finding commercial applications in the United States. Discussed in Chapter 15 are drilling cements developed mainly by the U.S. Department of Energy laboratories with industrial collaborations. Applications of CBPCs in the stabilization of hazardous and radioactive waste streams are discussed in Chapters 16 and 17. Finally, recent advances in CBPC bioceramics are covered in Chapter 18. Appendixes A, B, and C compile relevant thermodynamic and mineralogy data that were useful in writing the book. They serve as a ready reference to researchers who venture into further development of CBPCs. 

The paper considers how the updated metric, named Radiological Hazard Potential (RHP), can be summated for the radioactive waste streams on a particular site and used to help set priorities for future waste management activities. Uncertainties in RHP values may be utilised to prioritise further sampling and radio-analytical measurements. The paper outlines the difficulties in dealing with hazards posed by non-radioactive materials, and some cautionary advice is given on the correct application of the RHP, particularly in avoiding its use as the sole criterion for establishing work priorities. 

Chemical treatment is a weU-proven technique and is less expensive. Generally, specific chemical precipitation is carried out in situ in big tanks holding the radioactive waste stream to remove radionuclides while permitting nonradioactive ions to be released in the effluent from the process. The radionuchdes present in the waste are precipitated, co-precipitated, carrier precipitated, or adsorbed by insoluble compounds. A clariflocculator is used for flocculation and clarification. This technique is used as a batch or a semibatch process for large volumes of effluents containing only low concentrations of activity. It provides lower DF values (10-100) than evaporation. 

Since membrane distillation exhibits high abihty of concentration of aqueous solutions with high retention of acids, salts, and other low-volatile compounds, it can be used for concentration of different radioactive waste streams with high volume reduction and high retention factors [97-99]. 

River water Water Water Water Radioactive waste streams Water Sea water Sea water Dead Sea brine ASP Sea water and hot springs water... 

Complex transition metal ferrocyanide salts can be produced in crystalline and powdered forms and possess a very high selectivity for cesium in solutions having high salt concentrations. Potassium cobalt cyanoferrate (II) and sodium copper cyanoferrate (II) have been identified as useful reagents for cesium removal from radioactive waste streams and other cyanoferrates are capable of separating Cs from Rb and from a fission product mixture. 

This chapter has eonsidered the means by which the generation of gaseous, liquid and solid radioactive waste has been assessed as part of the APIOOO design process and minimised in line with best practiees. It then describes the processes by which each of the radioactive waste streams is managed and the either discharged or disposed of under controlled conditions or stoned on site in preparation for final geological disposal. 

The primary coolant in water cooied reactors and water from the fuel storage pools are major sources of liquid radioactive waste since some of their radioactive content may be transported to the liquid radioactive waste stream via process streams or leakages. Although the composition of the liquid radioactive waste may vary appreciably according to reactor type, contributions to the stream may derive from reactor coolant let-down, evaporator concentrates, equipment drains, floor drains, laundry waste, contaminated oil and waste arising from the decontamination and maintenance of facilities and equipment. 

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