First-generation reactors

Utilities. With approximately 1,(XX) reactor-y ofexpeiience,theutilities,ledbyEPRIrever5ed tl process by specifying the attributes for the n generation of plants. Requirements are g n in Table 6.1-6. By inference, this table criticizes the first generation reactors. 

Nine types of cores with different characteristics (power resource, fuel loading parameters, fuel emichment) were developed for first-generation reactor installations. Any of them could have been unloaded and stored at Gremikha. 

In 2001, EDF made the decision to dismantle all first generation reactors, including SuperPhenix up to the IAEA level 3 by the year 2025, without intermediate safe storage status (level 2). Phenix will remain operational, as mentioned before, through 2008-2009. 

Reactor capacity is limited by the system heat removal capability. Internal cooling coils cannot be used, as these will be quickly rendered useless by polymer film formation. Temperature eontrol in the first generation reactors was accomplished by cooling of the recycle gas. Capacity of the newer plants have... 

In the nuclear industry, stainless steel was used to clad the uranium dioxide fuel for the first-generation reactors. But by 1965, the force of neutron economy had made zirconium alloys the predominant cladding material for water-cooled reactors. There was a widespread effort to develop strong, corrosion-resistant zirconium alloys. Noticeably, the Ozhennite alloys were developed in the Soviet Union for use in pressurized water and stream. These alloys contain tin, iron, nickel, and niobium, with a total alloy content of 0.5-1.5%. The Zr-1% Nb alloy also is used in the Soviet Union for pressurized water and steam service. Researchers at Atomic Energy of Canada Ltd. took a lead from the Russians zirconium-niobium alloys and developed the Zr-2.5% Nb alloy. This alloy is strong and heat-treatable. It is used either in a cold-worked condition or a quenched-and-aged condition. 

The first generation of power reactors was designed by the vendors and offered to the... 

The chapter by Haynes et al. describes the pilot work using Raney nickel catalysts with gas recycle for reactor temperature control. Gas recycle provides dilution of the carbon oxides in the feed gas to the methanator, hence simulating methanation of dilute CO-containing gases which under adiabatic conditions gives a permissible temperature rise. This and the next two papers basically treat this approach, the hallmark of first-generation methanation processes. 

The chapter by White et al. proposes a different approach to metha-nator temperature control. Here the temperature rise is controlled by limiting the amount of reaction in each stage, and that is done by introducing steam (a product of the reaction). High initial temperatures are followed by successively lower temperatures entering each reactor in series. This is a second-generation methanation approach which may follow closely on the first-generation approaches typified by the previous three papers. 

Figure4.9 Chip system with triangular interdigital micro mixer-reaction channel. First- (top) and second- (bottom) generation reactor designs [22],...

Somewhat related is a process proposed and demonstrated on labscale by the University of Siegen (Germany). The process is called the (Herhof)-Integrierte Pyrolyse und Verbren-nung (IPV) process and is decribed in detail by Hamel et al.60 In this process, biomass is converted with high-temperature steam to pyrolysis gas in a fixed-bed reactor. The generated carbon from this reactor is led to a stationary FB combustor from which the hot ash is returned to the first-mentioned reactor. The ash works catalytically to reduce the tar content of the gas produced. The gas is further cleaned and conditioned using a scrubber and electrostatic filter from which the catch is returned to the FB combustor. 

Up to this point, the zinc-chloride-catalyzed PEER polymer can be considered as a first-generation PEER polymer. The product was prepared in glass reactors in small quantities. Nevertheless, it showed very interesting properties. 

The increase in efficiency between the first- and second-generation reactors was attributed to less water in the feed and lower operating temperatures. Reactor models indicated that the major source of heat loss was by thermal conduction. The selective methanation reactor lowered the carbon monoxide levels to below 100 ppm, but at the cost of some efficiency. The lower efficiency was attributed to slightly higher operating temperatures and to hydrogen consumption by the methanation process. Typical methane levels in the product stream were 5-6.2%. ... 

The Experimental Breeder Reactor EBR-1 was the first power reactor and the first fast neutron reactor. It was put in service in 1951 on the site of Idaho in the United-States and it became the world s first electricity-generating nuclear power plant when it produced sufficient electricity to illuminate four 200-watt light bulbs. 

The first research reactor, located in a rock cavern in Stockholm at the Royal Technical University, was commissioned in 1954. It operated until 1970 and was eventually dismantled in the 1980-s. The site has been decommissioned to green field and the rock cavern is now used for other activities without any radiological restrictions. Several research reactors were also operated in the nuclear national research laboratories in Studsvik. From 1964 to 1974 a heavy water moderated PWR reactor was operated for district heating purposes in a suburb to Stockholm but also generating electricity. It was intended as a demonstration facility. It is now waiting dismantling. 

The lirst-generation NSs were equipped with BM-A -type water-cooled thermal neutron reactors. Today it is very difficult to identify either the type or power production of cores unloaded from the first-generation NSs and stored in Gremikha. 

SFAs of reactor installations of the first-generation NSs were temporarily stored at two areas of the CMB at a special storage facility (Building 1) and outside storage facility in containers (types 6 and 11) at the open-air SRW TSF. 

The use of lithium as a solid compound, a pure melt, or a molten alloy is required for tritium breeding in at least the first generation of fusion reactors. Three fusion reactor concepts are discussed with emphasis on material selection and material compatibility with lithium. Engineering details designed to safely handle molten lithium are described for one of the example concepts. Tritium recovery from the various breeding materials is reviewed. Finally, two aspects of the use of molten Li-Pb alloys are discussed the solubility of hydrogen isotopes, and the influence of the alloy vapor on heavy ion beam propagation. 

The fusion reaction least difficult to initiate is the deuterium-tritium (DT) reaction which releases a 14.1 MeV neutron and a 3.5 MeV alpha particle. However, because neutrons activate the reactor structure, other fusion reactions have been considered. These reactions are either neutron free, or they produce fewer and less energetic neutrons. The required quality of confinement for these more desirable fusion reactions is much higher than for DT, and it is not yet clear if it will be achieved. Hence, fusion reactor designers have concentrated on the DT reaction for at least the first generation of fusion plants. 

Ion, S. et al., Pebble Bed Modular Reactor The First Generation IV Reactor to Be Constructed, paper presented at the World Nuclear Association Annual Symposium, London, September 3-5. 

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