Nuclear from plants

Krypton and Xenon from Huclear Power Plants. Both xenon and krypton are products of the fission of uranium and plutonium. These gases are present in the spent fuel rods from nuclear power plants in the ratio 1 Kr 4 Xe. Recovered krypton contains ca 6% of the radioactive isotope Kr-85, with a 10.7 year half-life, but all radioactive xenon isotopes have short half-Hves. 

About half of the world s nuclear power plants are from Westinghouse Electric Corporation or its Hcensees. One Westinghouse PWR design is the... 

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). 

Nuclear power plants of the future are to be designed and operated with the objective of better fiilfiUing the role as a bulk power producer that, because of reduced vulnerabiUty to severe accidents, should be more broadly accepted and implemented. Use of these plants could help stem the tide of environmental damage caused by air pollution from fossil-fuel combustion products (64). 

As of 1996, the bulk of spent fuel from nuclear power plants has been stored in specially designed water-filled holding pools at the reactor site. 

In 1980, Congress deterrnined that each state should be responsible for ensuring the proper handling and disposal of commercial low level nuclear wastes generated in their states. Regional disposal sites have also been estabHshed at BamweU, South Carolina, and Ward Valley, California. These wastes are handled by Hcensed disposal faciHties where they are packaged, placed in burial trenches, and covered with soil. Less than half of the low level nuclear waste produced annually in the United States comes from nuclear power plants. Low level nuclear power plant wastes include contaminated equipment. 

Adsorption of Radionuclides. Other appHcations that depend on physical adsorption include the control of krypton and xenon radionuchdes from nuclear power plants (92). The gases are not captured entirely, but their passage is delayed long enough to allow radioactive decay of the short-hved species. Highly rnicroporous coconut-based activated carbon is used for this service. 

Electric Power Generation. Coal is the primary fuel for thermal electric power generation. Since 1940 the quantity of bituminous coal consumed by electric utilities has grown substantially in each successive decade, and this growth is expected to continue for many years. Coal consumed by electric utilities increased from about 536 x 10 t in 1981 to 689 x 10 t in 1989 (2). The reasons for increased coal demand include availability, relative stability of decreasing coal prices, and lack of problems with spent fuel disposal as experienced in nuclear power plants (see Nuclearreactors). 

Process Water Purification Boiler feed water is a major process apphcation of RO. Sealants and colloids are particularly well rejected by membranes, and TDS is reduced to a level that makes ion exchange or continuous deionization for the residual ions very economic. Even the extremely high quahty water required for nuclear power plants can be made from seawater. The iiltra-high quahty water required for production of electronic microcircuits is usually processed starting with two RO systems operating in series, followeci by many other steps. 

Annual Reports of Gumulative System and Gomponent Reliability for Period from July 1, 1974, through December 31, 1982,serves as a source of engineering and failure statistics for the nuclear industry. It contains data for most components used in nuclear power plants. 

Releases of radioactive materials from nuclear power plants have occurred, as at Three-Mile Island, Pennsylvania. In such situations, releases may be sufficient to require evacuation of residents. 

Figure 1.4.3-1 from WASH-1400 compares the risk of 100 nuclear plants with other man-caused risks. This is a CCDF that gives the frequency per year that accidents will L-xcccd a value on the abscissa. For example, for 100 fatalities, the frequency that 100 nuclear power plants could do this is lE-4, air crashes to persons on the ground lE-2, chlorine releases 1. IE-2, dam failures 7E-2, explosions SF-2, fires 1. IE-1, air crashes (total) 5E-1, and total man-caused 9E-1,... 

Societal risks to life and health from nuclear power plant operation should be comparable to or less than the risks of generating electricity by viable competing technologies and should not be a significant addition to other societal risks. ... 

The risk to an average individual in the vicinity of a nuclear power plant of prompt fatalities that might result from reactor accidents should not exceed 0.1% of the sum of prompt fatality ri.sks from other accidents to which members of the U.S. population are generally exposed. ... 

Figures 2.8-1 and 2.8-2 from Vesely et al. (1983) show how the RAWR and RRWR measures vary for two PWR nuclear power plants (Oconee, and Sequoyah) based on their PSAs. This variation may be explained on the basis of different manufacturers of the plants (Babcock Wilcox and Westinghouse, respectively)...

According to 10 CFR 50,73, the holder of an operating license for a nuclear power plant (the licensee) must submit an LER for a reportable event, within 30 days after discovery. An event b reportable regardless of the plant mode, power level, structure, system, or component that initiated the event. In addition the licensee must report the completion of any nuclear plant shutdown required by the plant s Technical Specifications or any operation or condition prohibited by the plant s Technical Specifications, or any deviation from the plant s Technical Specifications. LERs are available on the Internet at http //www.nrc.gov/NRR/DAILY/97mmdddr.htm, where inrn is the... 

Table 4.3-3 from Joksimovich et al. (1983) presents the data sources used in preparing the Big Rock Point and Zion nuclear power plant PSAs. It is seen that both PSAs used plant records extensively. 

Suppose an interstate highway passes 1 km perpendicular distance from a nuclear power plant control room air intake on which 10 trucks/day pass carrying 10 tons bf chlorine each. Assume the probability of truck accident is constant at l.OE-8/mi, but if an accident occurs, the full cargo is released and the chlorine flashes to a gas. Assume that the winds are isotropically distributed with mean values of 5 mph and Pasquill "F" stability class. What is the probability of exceeding Regulatory Guide 1-78 criteria for chlorine of 45 mg/m (15 ppm). 

Flood Event Frequency Estimates were developed from flooding events in nuclear power plants with adjustments for plant-specific features and data. The data were from the IPE Surry flood analysis, industry sources, and licensing event reports (LERs). Some plant specific models were developed for the circulating water (CW) and service water (SW) lines... 

Initiating events, in this study, initiate plant scram or setback. Other initiators, such as refueling discharge accidents, do not necessarily cause a reactor shutdown but may lead t< minor fuel damage and radioactive releases. The list of initiators for nuclear power plants has litf ance for HFBR because of size and design differences. A list of HFBR-specific initiators was developed from " st prepared with the HFBR staff, the FSAR, the plant design manual, the procedures manual, techn specifications, monthly operating reports, and the HFIR PRA (Johnson, 1988). 

The external events PSA was based on standard methods used for commercial reactor PSAs, Fire risk was estimated from commercial nuclear power plant data combined with industrial fire information. The seismic hazard was evaluated using a combination of the EPRI and LLNL ( UREG/CR-.3250) databases. Wind hazards were analyzed by EQE, Inc., using NRC-based nicihodulogy. 

Data Acquisition and Parameter Estimation determines frequencies of the initiating events, component unavailability and probabilities of human actions were estimated from plant history. If insufficient, generic values were used including generic data from the nuclear industry (IAEA, 1988). In addition meteorological data and data on the population distribution around the plant were gathered and processed. 

Sacks, 1. J. et al., 1983, Systems Interaction Results from the Digraph Matrix Analysis of the Watts Bar Nuclear Power Plant High Pressure Safety Injection Systems, LLNL UCRI..-53467, December. 

Determination of Reliability Characteristic Factors in the Nuclear Power Plant Biblis B, Gesellschaft fur Reaktorsicherheit mbH Nuclear Failure rates with upper and lower bounds and maintenance data for 17,000 components from 37 safety systems Data for pumps, valves, and electrical positioning devices, electric motors and drives from an operating power plant 66. 

Reliability Data Book for Components in Swedish Nuclear Power Plants Power, Nuclear 30,000-t recorded events Safety and commercial grade components, i.e. pumps, valves, diesels, filters, tanks, and heat exchangers from 4 nuclear and non nuclear power generating plants 70. 

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