Flat plate reactors

Variables are defined in the nomenclature section. Differing from the case of the flat plate reactor where the radiation field in the employed part of the surface was almost uniform (differences were never larger than 9%), in this reactor the whole system exhibit only azimuthal symmetry and significant differences were observed in both directions (r, z). However, even more... 

It is always important to design a laboratory reactor that has the simplest mathematical representation for both the mass and the radiation balance. In this case the work was carried out in a flat plate reactor with circular windows made of quartz. A removable shutter permits to obtain steady-state operation of the whole system (including lamps) before the run commences. The start of the reaction (f = 0) occurs when it is taken off. Other features are described in Figures 11 and 12 and Table 6. Details on all the experimental procedure can be foimd in Labas et al. (2002). 

Flat plate reactors, being very simple for construction and analysis, are often used as a tool to obtain kinetic data, later to be used in the modeling of more complex system, for example, that of an annular reactor (Mohseni and Taghipour, 2004). 

Figure 13 Schematics of a flat plate reactor (after Salvado-Estivill et al., 2007a, b).

When the same value per unit suspension volume is needed (for equation 6.80) we must consider that (i) the cross-sectional area corresponding to the irradiated flat plate reactor is constant (a design condition), and (ii) the catalyst concentration is uniform (well-mixed system in the whole reactor volume an established operating condition) ... 

The most popular reactors are (1) parabolic trough reactors (PTRs), (2) compound parabolic collecting reactors (CPCRs), and (3) non-concentrating flat-plate reactors which are the double-skin sheet reactor (DSSR). 

Fig. 6.22 Flat-plate reactor used with a soluble iron catholyte and a bipolar membrane developed by ter Heijne et al. (2006). (A) Schematic of reactor. (Reprinted with permission of the American Chemical Society.) (B) Photograph of a clean reactor. (C) Reactor in operation with recycle lines for anode and cathode solutions. (Kindly provided by A. ter Heijne, WETSUS.)...

Fig. 2. High speed photos of organic film—high velocity air dynamics in falling film sulfonation process (a) and (b) are vertical flat plate organic—air dynamics where (a) shows BAB—air at top, (b) BAB sulfonic acid—air at bottom of reactor (c) simulated AUied-type concentric reactor inner cylindrical...

Equation (8.12) is a form of the convective dijfusion equation. More general forms can be found in any good textbook on transport phenomena, but Equation (8.12) is sufficient for many practical situations. It assumes constant diffusivity and constant density. It is written in cylindrical coordinates since we are primarily concerned with reactors that have circular cross sections, but Section 8.4 gives a rectangular-coordinate version applicable to flow between flat plates. 

The equivalent of radial flow for flat-plate geometries is Vy. The governing equations are similar to those for Vy. However, the various corrections for Vy are seldom necessary. The reason for this is that the distance Y is usually so small that diffusion in the y-direction tends to eliminate the composition and temperature differences that cause Vy. That is precisely why flat-plate geometries are used as chemical reactors and for laminar heat transfer. 

Reactors Assembled cost is 5/lb. Dished bottoms, open tops, height equal to diameter, bottom surface equals 1.5 times the surface of a flat plate of the same diameter. Tanks of over 1500 gal capacity are of 1/4" plate, smaller ones of 3/16" plate. Freeboard equals volume of the dished head. 

C H20/EtOH = 6-8 Residence time = 100 100 ms. Used an autothermal flat plate catalytic wall reactor... 

Extracorporeal devices to support a compromised liver were reviewed by Allen et al. and Strain and Neubcrgcr.Various nonbiological approaches such as hemodialysis or hemoperfusion over charcoal have met with limited success, presumably because these systems inadequately replaced the synthetic and metabolic functions of the liver. Conversely, biological approaches such as hollow fiber devices, flat plate systems, perfusion beds, and suspension reactors have shown encouraging results but are difficult to implement in a clinical setting. 

Another apparently undesirable aspect is the general layout of the reactor systems used in combination with the analysis technique [3-5]. The arrangement of samples on flat plates can be an acceptable compromise when it comes to simple reactions with essentially one reaction product, as with CO oxidation to C02 or the combustion of H2 and 02 to water. In the latter case, diffusion limitations... 

The idea of using fluidized bed as both uniform light distribution and an immobilizing support for photocatalysts has been originally proposed and theoretically evaluated by Yue and Khan [3]. Experimental application of this idea has been demonstrated by Dibble and Raupp [4] who designed a bench scale flat plate fluidized bed photoreactor for photocatalytic oxidation of trichloroethylene (TCE). Recently, Lim et al. [5,6] have developed a modified two-dimensional fluidized bed photocatalytic reactor system and determined the effects of various operating variables on decomposition of NO. Fluidized bed photocatalytic reactor systems have several advantages over conventional immobilized or slurry-type photocatalytic reactors [7,8]. The unique reac-... 

Rebrov et al. [158] synthesized ZSM-5 zeolite in micro channels. The main focus of this work was to assess the performance benefits of zeolitic coatings in micro channels compared with conventional zeolite-based pellets and powders. The coatings were performed in a sandwich of two plates of 1 cm length and width at a thickness of 2 mm. The plates carried seven channels each, which were 1 cm long and had a diameter of500 pm. The plates were positioned at a distance of280 pm from each other in the housing of the reactor. A zeolitic film of one crystal thickness was formed under the optimum synthesis conditions, which were determined as a water/silicon ratio of 130 and a template/aluminum ratio of 2 at a temperature of 130 °C after 35 h on a flat plate. The Si/Al ratio of the zeolite, which also lowers the crystal size when decreased, was optimized to a value of 28. 

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