Reactor design comparison table

The kinetic parameters chosen for comparison are rate constants and t1/2. Radiation influences and the effect of reactor design are usually identical when these kinetic data are compared between the various AOPs tested. The values for pseudo first-order kinetics and half-lives for various processes are given in Table 14.3. In most cases, the values of f3/4 are equal to two times those of t1/2 therefore, the reactions obey a first-order kinetics. Figure 14.5. shows that Fenton s reagent has the largest rate constant, e.g., approximately 40 times higher than UV alone, followed by UV/F C and Os in terms of the pseudo first-order kinetic constants. Clearly, UV alone has the lowest kinetic rate constant of 0.528 hr1. 

Table 1. Comparison of the major characteristics of three conceptual tokamak power reactor designs of the University of Wisconsin...

Eor the convenience of the reader, the AP600 and APIOOO are compared with the largest conventional reactor design that preceded them. The comparison of key parameters is given in Table 2.4. Following that is a detailed discussion of changes in tiie design from fhaf described above in earlier subsections. Much has been done to improve neutron... 

Tables 1 and 2 tabulate the above mentioned fuel cycle dynamic response characteristics for selected open cycle and closed cycle concepts of small reactors without on-site refuelling, based on the inputs provided by designers in the corresponding annexes. For comparison. Table 3 lists the corresponding values for typical LWRs [2] and projected high-breeding LMFBRs [3]. IHM is for initial heavy metals and CR is for conversion (or breeding) ratio.

Fast Reactor Design Table 7.35 Comparison of core design results. (Taken from [30] and used with permission from Atomic Energy Society of Japan) ... 

Figure 13.19 shows a comparison between the experimental (plots) and simulated (lines) results for Cases 21-23 in Table 13.5, where both conversion and hydrogen permeation rate can be found to be in good agreement. This indicates that the CFD model developed here is valid for analysing the multi-tubular membrane reactor designed in this text. 

Five percent random error was added to the error-free dataset to make the simulation more realistic. Data for kinetic analysis are presented in Table 6.4.3 (Berty 1989), and were given to the participants to develop a kinetic model for design purposes. For a more practical comparison, participants were asked to simulate the performance of a well defined shell and tube reactor of industrial size at well defined process conditions. Participants came from 8 countries and a total of 19 working groups. Some submitted more than one model. The explicit models are listed in loc.cit. and here only those results that can be graphically presented are given. 

The above computation is quite fast. Results for the three ideal reactor t5T)es are shown in Table 6.3. The CSTR is clearly out of the running, but the difference between the isothermal and adiabatic PFR is quite small. Any reasonable shell-and-tube design would work. A few large-diameter tubes in parallel would be fine, and the limiting case of one tube would be the best. The results show that a close approach to adiabatic operation would reduce cost. The cost reduction is probably real since the comparison is nearly apples-to-apples. ... 

The choice of reactor will be very dependent on the requirements of the chemical reaction scheme, the relative importance of mixing and heat transfer, and practical considerations (e.g., the effect of solids in the process materials of construction flexibility). A comparison of the typical performance of different designs is given in Table 5. HEX Reactors are discussed in more depth in Chapter 4. 

A comparison of this design with the moderate reaction design (Table 6.8) shows that the larger specific reaction rate produces a smaller reactor with less recycle, less heat transfer area, and lower TAC. 

To show the uniqueness of the optimum design, a comparison was made with an alternate reactor of identical volume but shorter length and larger diameter. Results are shown in Table V. The alternate reactor does not meet both the residence time and tubeskin temperature specifications. 

The HTR-10 test reactor was erected in 2000. First criticality was achieved in December 2000. Full power operation was achieved in January 2003. Since then, the HTR-10 has been under operation. Valuable operational experience is under accumulation. Important safety experiments have been performed with HTR-10. Overall, the construction and operation of HTR-10 has been very successful so far. Table 2 shows the comparison of key design and operation data. 

Table 9 provides a comparison of the suitability of the two reactor types with regard to major SCWO design factors. Potential clients should work with the SCWO vendor, as key features such as reactor temperature, pressure, and residence time will vary for the different reactor types as well as for the feed material. 

It is instructive to compare gas-liquid reactors (from all the classes) on the basis of capacity, turndown ratio (L/G), liquid-phase axial mixing, gas-side pressure drop, mass transfer coefficient, effective interfacial area, heat transfer coefficient, and the number of theoretical stages. Table 11.26 presents such a comparison using ratings 1 to 5 (poor to excellent). This table should be useful to design engineers. 

The calculated elemental composition, radioactivity, and decay-heat rate for discharge fuel are shown in Table 8.7 for the uranium-fueled PWR (cf. Fig. 3.31), in Table 8.8 for the liquid-metal fast-breeder reactor (LMFBR) (cf. Fig. 3.34), and in Table 8.9 for the uranium-thorium-fueled HTGR (cf. Fig. 3.33). These quantities, expressed per unit mass of discharge fuel, are useful in the design of reprocessing operations. For the purpose of comparison, all quantities are calculated for 150 days of postirradiation cooling. 

The last two characteristics are primarily due to the unique HTGR fuel element design and the rather innocuous environment of the core. Table I Illustrates this point with a comparison of HTGR effluents with those from Bolling Water Reactors (BWR) and Pressurized Water Reactors (PWR). 

Comparison of turbulent diffusion coefficients Dt in various regions of tubular reactor showed (Table 3.2) that apparatus of divergent-convergent design provides in volume the field of Dt homogeneous enough (for comparison of characteristic times of diffusion Tmix and chemical reaction... 

Irradiation Embrittiement of Reactor Pressure Vesseis (RPVs) Table 3.1 Comparison of main design parameters of WWER RPVs... 

Further trends in the development of RPVs for third-generation reactors can be seen in Table 3.6, where comparison of three different designs is given. The following trends can be seen ... 

In terms of industrial use, the aforementioned three-phase slurry reactors are in themselves amenable for qualitative comparison in terms of their physical attributes and the various operating parameters. While the specifics of these attributes are determined by the process chemistry and detailed design (guidelines to which is discussed later in this chapter), Table 6.4 provides at a glance qualitative comparison of these attributes. 

Table 2.16 Comparison of optimum design conditions between sharpcooling and heat-exchange for multi-beds reactor...

Seven samples with different characteristics were prepared and tested, as summarized in Table 28.6. Thus, samples A and B shared the same geometry, but their support was made of aluminium and of stainless steel, respectively, so that a comparison of their thermal behaviour would provide direct information concerning the influence of the intrinsic conductivity of the support material, which is smaller by approximately a factor of ten in the case of steel. Likewise, the other samples were designed and prepared to collect experimental evidence on the role of the thickness of the slabs (sample C), washcoating method (sample D), washcoat load (sample E), volume fraction of metallic support (sample F) and contact thermal resistance at the reactor wall (sample G). 

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