Nuclear power reactors pressurized water reactor

This appendix provides additional materials (schematics, layouts, T—s diagrams, basic parameters, and photos) on advanced thermal (combined cycle and supercritical pressure Rankine steam turbine cycle) power plants and nuclear power plants with modern nuclear power reactors [pressurized water reactors (PWRs), boiling water reactors (BWRs), pressurized heavy water reactors (PHWRs), advanced gas-cooled reactors (AGRs), gas-cooled reactors (OCRs), light water-cooled graphitemoderated reactors (LGRs) (RBMKs and EGPs), and liquid metal fast-breeder reactors (LMFBRs) (BN-600 and BN-800)]. 

To produce power, a fission nuclear reactor requires fissile material. Generation II or in reactors (pressurized water reactor [PWR], CANDU, evolutionary power reactor [EPR], etc.), being imder-breeder systems (ie, using more fissile material than they... 

One of the most significant sources of change in isotope ratios is caused by the small mass differences between isotopes and their effects on the physical properties of elements and compounds. For example, ordinary water (mostly Ej O) has a lower density, lower boiling point, and higher vapor pressure than does heavy water (mostly H2 0). Other major changes can occur through exchange processes. Such physical and kinetic differences lead to natural local fractionation of isotopes. Artificial fractionation (enrichment or depletion) of uranium isotopes is the basis for construction of atomic bombs, nuclear power reactors, and depleted uranium weapons. 

Fig. 1. Pressurized water reactor (PWR) coolant system having U-tube steam generators typical of the 3—4 loops in nuclear power plants. PWR plants having once-through steam generators contain two reactor coolant pump-steam generator loops. CVCS = chemical and volume-control system.

Because of its low neutron absorption, zirconium is an attractive stmctural material and fuel cladding for nuclear power reactors, but it has low strength and highly variable corrosion behavior. However, ZircaHoy-2, with a nominal composition of 1.5 wt % tin, 0.12 wt % iron, 0.05 wt % nickel, 0.10 wt % chromium, and the remainder zirconium, can be used ia all nuclear power reactors that employ pressurized water as coolant and moderator (see... 

Zirconium is used as a containment material for the uranium oxide fuel pellets in nuclear power reactors (see Nuclearreactors). Zirconium is particularly usehil for this appHcation because of its ready availabiUty, good ductiUty, resistance to radiation damage, low thermal-neutron absorption cross section 18 x 10 ° ra (0.18 bams), and excellent corrosion resistance in pressurized hot water up to 350°C. Zirconium is used as an alloy strengthening agent in aluminum and magnesium, and as the burning component in flash bulbs. It is employed as a corrosion-resistant metal in the chemical process industry, and as pressure-vessel material of constmction in the ASME Boiler and Pressure Vessel Codes. 

The DOE N-Reactor is one of the plutonium production reactors located on the Hanford Reservation near Richland, Washington. It is graphite moderated, pressurized water reactors that in addition to production of special nuclear materials also provided steam to turbine generators owned by the Washington Public Power Supply System for electric power production. It began op ition in 1 is put into standby status in 1988 and closed because of similarities to Chernobyl. 

There are various types of nuclear power reactors, including boiling water reactors (BWR) and pressurized water reactors (PLWR or LWR), which are both light-water reactor (LWR) designs and are cooled and moderated by water. There also are pressurized heavy-water reactor (PHWR or HWR) designs. 

All over the world, 432 nuclear power reactors are under operation and more than 36 GW of electricity could be produced as of December 31, 2001. There are several types of reactors such as boiling water reactor (BWR), pressurized water reactor (PWR), Canada deuterium uranium (CANDU), and others. In these reactors, light water is normally used not only as a coolant, but also as a moderator. On the contrary, in CANDU reactors, heavy water is taken. It is widely known that the quality control of coolant water, the so-called water chemistry, is inevitably important for keeping the integrity of the plant. 

Pressurized Water Reactor (PWR) A type of nuclear power reactor that uses ordinary water as both the coolant and the neutron moderator. The heat produced is transferred to a secondary coolant which is subsequently boiled to produce steam for power generation. 

Boiler tubes are often cleaned with EDTA or NTA solutions to remove both CaC03 scale and corrosion products. In pressurized heavy water nuclear power reactors, radioactive corrosion deposits (in effect, magnetite in which some of the Fe has been replaced by radioactive Co ) can be removed from the coolant water circuits with an aqueous mixtiu e of oxalic and citric acids (both good chelators for Fe " ") and EDTA. In home laundry operations, bloodstains on clothing can be removed by treatment with oxalic acid, which takes up the iron from the hemoglobin (Section 8.2) as Fe(ox)3 . By the same token, oxalates axe toxic when taken internally, as are many other complexing agents. For example, EDTA is used as a means... 

To relate these resource estimates to nuclear electric generation, it may be noted that a 1000-MWe pressurized-water reactor operating at 80 percent capacity factor without recycle, on uranium enriched to 3.3 w/o (weight percent) U in an enrichment plant stripping natural uranium to 0.3 w/o U, consumes around 200 MT of uranium per year. Thus the U.S. resource estimate of 1758 thousand MT available at less than 50/lb UgOg would keep a 300,000-MWe nuclear power industry in fuel for... 

A concept of an evolutionary reactor is pursued with the joint French / German European Pressurized Water Reactor , EPR, a 1525 MW(e) plant with evolutionary steam generating system and innovative double-walled containment [20]. A three years basic design phase as a prerequisite for the beginning of the licensing procedure was finished in 1997. The characteristic feature is a core catcher to restrict a possible core melt to the power plant itself. The joint effort by Germany ind France, however, finds in both countries a situation where no further base load is required. The EPR, confirmed as a future standard in France, is projected to substitute decommissioned nuclear plants. 

FIG. 19.2. Main components of a pressurized light water cooled and -moderated nuclear power reactor (PWR) and a view of the Ringhals plant (Sweden) with 3 PWRs and 1 BWR. 

All nuclear power reactors outside the previous USSR and CMEA countries have a reactor containment building, the purpose of which is to contain steam and released radioactivities in case of a severe accident, and to protect the reactor from external damage. The contairunent is designed (and tested) to withstand the internal pressure from a release of the water in the entire primary cooling circuit (and in the case of PWRs of the additional loss of one of the steam generators), corresponding to excess pressures of 0.4 MPa. The containmrat is provided with a spray, which cools and condenses the steam released and... 

An example is the SCC of stainless steel at 200 °C in a caustic solution or in aerated chloride solution where no traces of dissolution are visible on the crack face. The three conditions, namely, tensile stress, susceptible sample material, and a corrosive environment are the conditions necessary for stress corrosion to take place (73, 90). For instance, SCC of metals has been by far the most prevalent cause of failure of steam generator components in pressurized water reactors (PWRs) to an extent of 69% of all cases, piping in boiling water reactors (59.7%) and PWRs (23.7%). More than 60% of inspected steam turbines in nuclear power plants have disks with stress corrosion cracks (91). 

The total cost of electricity sold in the United States in 1998 was 3.24 million gigawatt hours at a cost to consumers of 218.4 billion. The electricity generation plants use fossil fuel, nuclear, hydroelectric, cogeneration, geothermal, solar, and wind energies. The major players are fossil and nuclear steam supply systems. The two types of nuclear reactors are boiling water and pressurized water reactors. Some relevant data on the costs of corrosion estimated in 1998 are as follows nuclear facilities 1,546 billion fossil fuel sector 1,214 billion transmission and distribution 607 million hydraulic and other power 66 million. The total cost of corrosion in the electrical utilities industry in 1998 is estimated at 6,889 billion/year. 

Mihama-3 is an 826 MW Mitsubishi-built pressurized water reactor (PWR) plant situated in Mihama, Japan, 320 km west of Tokyo. The carbon steel pipe carried the high-temperature steam at high pressure and the pipe was not inspected since the inception of the plant in 1976. In April 2003, Nihon Arm, a maintenance subconttac-tor informed Kansai Electric Power Company, the plant owner, that there could be a problem. Then the power company scheduled an ultrasonic inspection for August 2004. Four days before the scheduled inspection, superheated steam blew the 60-cm wide hole in the pipe. The steam that escaped was not in contact with the nuclear reactor and hence no nuclear contamination has been reported. 

Two-circuit reactor plant (RP) with a vessel-type pressurized water reactor is used for floating power unit of nuclear head and power station. Basic RP components reactor, steam generators and primary coolant pumps are incorporated by pressure nozzles in a compact steam-generating block. KLT-40C RP characteristics are given in Table 1. 

The first nuclear power reactor in the USSR was a graphite moderated pressure tube design cooled by pressurised water. It started generating electricity in 1954. 

Figure 21.19 Basic design of a pressurized water reactor nuclear power plant. 

Six of the seven nuclear submarines contained two pressurized water reactors (PWRs) each. Eleven of these PWRs were dumped into the Kara Sea between 1965 and 1988 eight within and three without their reactor compartments (RCs). AH these nuclear submarines suffered some form of reactor accident however, many specifics of the reactor design, maximum thermal power, compartment layout, detailed operating histories, and accident scenarios remain classified. 

Abstract This chapter describes the surveillance database of the Western pressurized water reactor (PWR) reactor pressure vessel (RPV) beltline materials obtained from US, French and Japanese nuclear power plants (NPPs) and those from other countries, together with an overview of the characteristics of PWR RPVs. Trends of surveillance data which will be obtained in the near future and the possibility of new data from reconstituted and miniature specimen techniques are presented. 

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