Other Reactor Concepts

In reality, these are only two of many arrangements that could be devised to create and deliver to a substrate large quantities of reactive species using a plasma. Since there are many shortcomings to existing commercial plasma-enhanced CVD reactors, it will be useful to explore other reactor concepts that are under development, but have yet to be widely developed commercially. Whether or not they will lead to practical production systems remains to be seen. 

Other reactor concepts show similar features (see [1] and [4]), which include boundary layer control and internal recirculation. Reference [5] proposes boundary layer control utilizing transpiration cooling. 

With regard to the achievement of NRC criteria for the accomplishment of Goal 1 and 2 functions, measures are taken in the design of the Standard MHTGR, as they are in other reactor concepts, to minimize defects in the fuel and to purify the primary circuit of any radionuclides which do escape the fuel so that normal operational releases or any accidental releases of primary circuit... 

The evaluated concepts foresee partly different fuel cycles. Rssion reactors can be operated in principle on the basis of eittier a Uranium-Plutonium-cycle or a Thorium-Uranium-cycle, while combinations of these cycles among them or with other reactor concepts than proposed are possible. With t(xja/s nuclear park (comprising mainly LWRs), the world-wide plutonium excess increases annually by about 1001. Besides strategies based on reprocessing like... 

The micro reactor contained a heating function (imlike [R 4] and the other versions of this reactor concept [R 5] and [R 6], decribed below) via a heating wire connected to a potentiostat [19], This wire was integrated into the micro reactor by placing it in the mold before pouring the liquid PDMS. 

From the very beginning, continuous reactor concepts, an alternative to the truly microfabricated reactors, were used, for example, static meso-scaled mixers or HPLCs and other smart tubing (see Iwasaki et al. 2006 for an example). This completed functionality by filling niches not yet covered by microfabricated reactors or even by replacing the latter as a more robust, more easily accessed or more inexpensive processing tool. Further innovative equipment, coming from related developments in the process intensification field, is another source e.g., structured packings such as fleeces, foams, or monoliths. 

Also, there is serious question as to whether such a system would be capable of obtaining a RCRA Part B Permit to operate without formal air emission control systems. These open tank systems are designed to be crude but effective. When one begins to collect flammable and toxic gases over such open tanks and to allow access of fork lift trucks to deliver and retrieve hoppers of slag, the logic of the system falls apart very quickly and one returns to the reactor concept or other options. 

This section has presented a brief review of some of the important kinetic concepts encountered in reactor analysis, modeling, and control. These concepts must be understood within the context of how they affect reactor temperature control and other aspects of reactor control. We recognize that many excellent reference books on chemical reaction engineering are available. These books cover the topic of kinetics and a host of other reactor design concepts in extensive depth. Our intention is not to attempt to provide anything like the scope of that material, so we assume some familiarity with it. A short list of excellent reference books includes... 

Closer inspection reveals that this somewhat superficial and largely self-evident evaluation is by no means exhaustive, and concrete experimental studies on adsorptive reactors expose both additional pitfalls and benefits that are often specific for a particular reaction system and decisive for the success or otherwise of adsorptive reactor concepts. Before illustrating this point with the help of four examples with which the author is personally acquainted - the Claus reaction, the direct hydrogen cyanide synthesis from ammonia and carbon monoxide and, to a lesser extent, the water-gas shift reaction and the Deacon process - it is worthwhile briefly reviewing other reaction systems for which the potential of adsorptive reactors has been examined (Tab. 7.2). 

HEU) or mixed oxide (MOX) fuel containing oxides of uranium and plutonium in commercial nuclear power reactors, in order to dispose of nuclear weapons materials. Other theoretical reactor concepts are also being investigated for disposal of actinides. 

Several other ICF reactor concepts use liquid metal walls (Ii W). These include the Los Alamos National Laboratory (LANL) wetted wall concept, the Bechtel concept called EAGLE (which uses a lithium spray in the chamber), the Lawrence Livermore National Laboratory (LLNL) concept called JADE (which uses a fiber-metal structure to control liquid metal flow), and the German/University of Wisconsin concept called HIBALL (which uses carbide "socks" to control liquid metal flow). 

It is beyond doubt that it is very well possible to manufacture BSR catalyst packings. Valid questions are, however, how the manufacturing costs of a BSR compare to those of other reactors with structured catalyst packings, and which reactor engineering advantages the BSR concept offers in specific applications. 

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