Nuclear power, possibilities

Nuclear Applications. Powder metallurgy is used in the fabrication of fuel elements as well as control, shielding, moderator, and other components of nuclear-power reactors (63) (see Nuclearreactors). The materials for fuel, moderator, and control parts of a reactor are thermodynamically unstable if heated to melting temperatures. These same materials are stable under P/M process conditions. It is possible, for example, to incorporate uranium or ceramic compounds in a metallic matrix, or to produce parts that are similar in the size and shape desired without effecting drastic changes in either the stmcture or surface conditions. OnlyHttle post-sintering treatment is necessary. 

If possible comparisons are focused on energy systems, nuclear power safety is also estimated to be superior to all electricity generation methods except for natural gas (30). Figure 3 is a plot of that comparison in terms of estimated total deaths to workers and the pubHc and includes deaths associated with secondary processes in the entire fuel cycle. The poorer safety record of the alternatives to nuclear power can be attributed to fataUties in transportation, where comparatively enormous amounts of fossil fuel transport are involved. Continuous or daily refueling of fossil fuel plants is required as compared to refueling a nuclear plant from a few tmckloads only once over a period of one to two years. This disadvantage appHes to solar and wind as well because of the necessary assumption that their backup power in periods of no or Httie wind or sun is from fossil-fuel generation. Now death or serious injury has resulted from radiation exposure from commercial nuclear power plants in the United States (31). 

One of the products of a nuclear power plant PSA is a list of plant responses to initiating events (accident starters) and the sequences of events that could follow. By evaluating the significance of the identified risk contributors, it is possible to identify the high-risk accident. sequences and take actions to mitigate them. 

Chemical Industry - has risks comparable to or possibly greater then those of the nuclear power industry, but no risk studies of chemical plants in the U.S. have been published. Great Britain, on the other hand, has been active in this area, e.g., the Canvey Island Study (Section 11.4.1 and Green, 1982). 

FMEA is particularly suited for root cause analysis and is quite useful for environmental qualification and aging analysis. It is extensively used in the aerospace and nuclear ]iowei indiistrii-s but seldom used in PSAs, Possibly one reason for this is that FMEA, like parts count. ,s not chrectlv suita lundant systems such as those that occur in nuclear power plants Table i 4... 

Chernobyl may represent the upper limit that is possible in a nuclear power plant accident. 

In the WASH-1400 analyses of nuclear power accidents, it was calculated that it is possible to overpressure and rupture the containment. Discuss whether this is better or worse than a pressure relief that releases radioactivity but prevents the pressure from exceeding the rupture... 

The purpose of regulation is to protect the public from the risk of nuclear power. PSA make it possible to express the risk numerically. However, NRC regulations have been pro.scriptive to achieve an unknown risk level. Clearly too much regulation that destroys the industry is not desirable and too little may fail to protect the public. A possible solution is the use of PSA in regulations. Such has been resisted because of the uncertainties on the other hand there are uncertainties in proscriptive regulation but no attempt is made to express them quantitatively. The following condenses material from Murphy (1996) to reflect NRC thinking on this subject. 

Taking into account the possibility of highly directional blast effects, Eichler and Napadensky (1977) recommend the use of a safe and conservative value for TNT equivalency, namely, between 20% and 40%, for the determination of safe standoff distances between transportation routes and nuclear power plants. This value is based on energy it should be applied to the total amount of hydrocarbon in the largest single, pressurized storage tank being transported. 

Tlie advances of modern teclmology have brought about new problems. Perliaps tlie most serious of these is tlie tlireat of a nuclear power plant accident known as a meltdown. In tliis section several of tliis era s most infamous accidents are examined some possible explanations are also offered. 

Westinghouse constructs its Atom Smasher in Forest Hills, Pennsylvania. The five million volt van de Graaff generator represents the first large-scale program in nuclear physics established in industry, makes possible precise measurements of nuclear reactions, and provides valuable research experience for the company s pioneering work in nuclear power. 

Zero solids treatment (ZST) is a further enhancement of AVT and MT programs and, as its name suggests, the program employs extensive pre- and post-treatment equipment to ensure the highest possible FW and BW purity. ZST has been employed in the secondary circuits of nuclear-powered SGs as an aid in the prevention of SCC, crevice corrosion, and denting, especially where condenser cooling is effected by the use of brackish or estuarine waters. 

A few nations rely heavily on nuclear power despite the possibility of accidents. In France and Japan, fission power from nuclear reactors provides two thirds or more of overall energy needs. A French plant appears in Figure 22-14C. 

The nuclear power plant accident at Chernobyl in April 1986 (IAEA Technical Report 1991) proved to be a much more potent source of environmental contamination in many surrounding countries, over distances up to several thousands of kilometers, and was a cause of worldwide problems in international trade in food products contaminated (or possibly contaminated) with radionuclides. The resulting requirement by many countries to establish systems for monitoring radionuclides in foodstuffs and in the environment led to a large worldwide increase in the demand for suitable reference materials. 

Am may enter surface water from nuclear power plants sited on the shores. A region of possible concern is the Great Lakes where 35 nuclear facilities are located in the lakes basin. A sample of water from Lake Ontario collected in 1985 and fdtered through a 0.45 pm Millipore filter contained 0.3 mBq 241Am/L (8 fCi/L) (Platford and Joshi 1986). A few water samples from the Savannah River, which received runoff and discharges from the DOE Savannah River Plant, contained 0.05 fCi 241Am/L (2 pBq/L), about the same levels as other American rivers (DOE 1980). 

It is therefore vital that the United States in particular and all developed countries, emphasize nuclear power in meeting electric power needs, and to the extent possible substitute uranium for fossil fuel. It is equally critical that, as aging nuclearfiacilities are taken out of commission, replacement power generation be nuclear and not fossil fuel. 

Once all these requirements are met, it may be possible to get to a point when the public will see that the advantages of nuclear power outweigh the risks. Only then might it reduce its opposition... 

The use of coal for electricity generation is responsible for about 32% of anthropogenic carbon dioxide emissions in the U S. 11 As shown by France, it is possible to displace virtually all the coal used in electricity generation. Thus, France in 1997 obtained about 78% of its electricity from nuclear power and only about 5% from coal. Further reductions in carbon dioxide emissions could be made by the electrification of other sectors of the energy economy, including buildings, and eventually perhaps much of transportation. 

In what way and how much do the military origins and uses of fission energy impact the prospects for revival ofthe nuclear power option Are they a serious impediment are they of little significance or is it just possible that, if fully understood, the military implications are a positive factor No assessment of the future of nuclear power can be complete without consideration ofthe military use issue, the essence of which is the potential spread of nuclear weapons to additional countries or even subnational entities. This paper reviews this issue, giving particular attention to international nuclear safeguards, certainly the most distinctive, and probably the most misunderstood feature of the nuclear nonproliferation regime. 

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