Test reactors

Tokamak Fontenay-aux-Roses Tokamak Fusion Test Reactor... 

The second important component is the cooling agent or reactor coolant which extracts the heat of fission for some usefiil purpose and prevents melting of the reactor materials. The most common coolant is ordinary water at high temperature and high pressure to limit the extent of boiling. Other coolants that have been used are Hquid sodium, sodium—potassium alloy, helium, air, and carbon dioxide (qv). Surface cooling by air is limited to unreflected test reactors or experimental reactors operated at very low power. 

A series of tests were performed at the AFC s National Reactor Testing Station in Idaho, starting in 1953. The reactor was situated outdoors, and was operated remotely. The core of the first version had fuel assembhes of aluminum and enriched uranium plates of the Materials Testing Reactor (MTR) type, installed in a water tank. One of the five control rods could be ejected downward and out of the core by spring action upon intermption of a magnet... 

Nuclear reactor and generator at Argonne National Laboratory used primarily for research and development in testing reactor fuels as weU as for training. The generation from the unit is used for internal consumption. 

Uranium-235 Enrichment. The enrichment of uranium is expressed as the weight percent of in uranium. For natural uranium the enrichment level is 0.72%. Many appHcations of uranium requite enrichment levels above 0.72%, such as nuclear reactor fuel (56,57). Normally for lightwater nuclear reactors (LWR), the 0.72% natural abundance of is enriched to 2—5% (9,58). There are special cases such as materials-testing reactors, high flux isotope reactors, compact naval reactors, or nuclear weapons where enrichment of 96—97% is used. 

Fig. 1. Volume change in anisotiopic giaphite during General Electric Test Reactor (GETR) irradiations. Courtesy of Oak Ridge National Laboratory, managed by Martin Marietta Energy Systems, Inc. for the U.S. Department of Energy under Contract No. DE-AC05-840R21400.

Bosch and co-workers devised laboratory reactors to operate at high pressure and temperature in a recycle mode. These test reactors had the essential characteristics of potential industrial reactors and were used by Mittasch and co-workers to screen some 20,000 samples as candidate catalysts. The results led to the identification of an iron-containing mineral that is similar to today s industrial catalysts. The researchers recognized the need for porous catalytic materials and materials with more than one component, today identified as the support, the catalyticaHy active component, and the promoter. Today s technology for catalyst testing has become more efficient because much of the test equipment is automated, and the analysis of products and catalysts is much faster and more accurate. 

Catalyst testing and evaluation have been revolutionized by computers, automated test reactors, and analytical methods. With modem equipment, researchers can systematically prepare and screen many catalysts in a short time and efftciendy deterrnine, not only the initial catalytic activity and selectivity, but also the stabiUty and the appearance of trace products that may indicate some new catalytic properties worthy of further development. 

High Temperature Test Reactor, HTTR (Japan)... 

Atkinson. S. A., 1996, PSA-Operations Synergisms for Advanced Test Reactor Shutdown Operations PSA, Proceeding of the Int ——1 Topical Meeting on Probabilisl ety Assessment, Park City, Utah, pp 600-6 29-Oct. 3. 

Atkinson, S. A. et al, 1993, Advanced Test Reactor Probabilistic Risk Assessment, Pr<... 

Eide, S. A. et al., 1990a, Advanced Test Reactor Level 1 Probabilistic Risk Assessment, ANS Topical Meeting, The Safety, Status, and Future of Non-Commercial tors and Irradiation Facilities, Boise ID, Sept. 31 - October 4,1990. 

The Tokamak Fusion Test Reactor at the Princeton Plasma Physics Laboratoi y produces fusion. 

Tests 2 and 3 were run in the same reactor as Test 1. In order to confirm the initial activity, the catalyst was started up without added sulfur. The catalyst picked up sulfur in both these tests and was deactivated even though no sulfur was added to the feed this indicates that sulfur remained in the reactor after Test 1. This is a common problem encountered when working with sulfur in laboratory test reactors. The sulfur reacts with the steel walls of the reactor. Then, even though sulfur is removed from the feed, sulfur evolves from the walls of the reactor and it is either picked up by the catalyst or it appears in the effluent from the reactor. With continuous addition of sulfur, the CO leakage continues to increase. 

The facilities at Savannah River(j)) consist of five heavy-water-moderated and cooled production reactors, two chemical separations areas as a heavy water extraction plant, several test reactors, reactor fuel and target processing facilities, the Savannah River Laboratory, and many other facilities necessary to support the operations. During the 1960 s, two of the... 

FIGURE 17.27 Research into controlled nuclear fusion is being carried out in several countries. Here we see the Tokomak fusion test reactor at the Princeton Plasma Physics Laboratory. 

The photocatalytic experiments were performed in a horizontal quartz tube which it have TiOi. Illumination was provided by 500 W mercury lamps, located above the horizontal quartz tube. The reactant was 0.1% (v/v) ethylene in air. In case of Photo-Catalyst test, reactor effluent samples were taken at 30 min intervals and analyzed by GC. The composition of hydrocarbons in the feed and product stream was analyzed by a Shimadzu GC14B (VZIO) gas chromatograph equipped with a flame ionization detector. In all case, steady state was reached within 3 h. 

In industry, as well as in a test reactor in the laboratory, we are most often interested in the situation where a constant flow of reactants enters the reactor, leading to a constant output of products. In this case all transient behavior due to start up phenomena have died out and coverages and rates have reached a constant value. Hence, we can apply the steady state approximation, and set all differentials in Eqs. (142)-(145) equal to zero ... 

Jensen gives several examples for his present highly integrated chip systems [101], including a gas-phase reactor, a liquid-phase reactor, a catalyst-testing reactor, and a packed-bed multi-phase reactor. In addition, he provides the vision of a multiple micro-reactor test station (see Section 1.5.5.2). 

A growing number of research groups are active in the field. The activity of reforming catalysts has been improved and a number of test reactors for fuel partial oxidation, reforming, water-gas shift, and selective oxidation reactions were described however, hardly any commercial micro-channel reformers have been reported. Obviously, the developments are still inhibited by a multitude of technical problems, before coming to commercialization. Concerning reformer developments with small-scale, but not micro-channel-based reformers, the first companies have been formed in the meantime (see, e.g., ) and reformers of large capacity for non-stationary household applications are on the market. 

A test reactor was made of stainless steel which contains a so-called micro-strip electrode array [75]. This array is composed of thin strips surrounded by larger objects. The anodes are thin gold strips evaporated on glass bulk. The cathodes have a more complex bulky pattern similar to an oval. 

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