Reactors production-scale microstructured

Of course, the benefits of microfabricated and stractured reactors are also applicable to even larger scale processes. For example, Evonik s development of a production-scale microstructured reactor for vinyl acetate manufacture (150000t per annum) claims depreciation and operating cost savings of 3 million per year [25]. 

Membrane reactors are known on the macro scale for combining reaction and separation, with additional profits for the whole process as compared with the same separate functions. Microstructured reactors with permeable membranes are used in the same way, e.g. to increase conversion above the equilibrium limit of sole reaction [8, 10, 11, 83]. One way to achieve this is by preparing thin membranes over the pores of a mesh, e.g. by thin-fihn deposition techniques, separating reactant and product streams [11]. 

The relevant shares in the cost calculations change when microprocess technology approaches large-scale chemical production (U. Krtschil et al., unpublished data). Reactor fabrication at a competitive cost becomes crucial and is among the main cost drivers. The corresponding costs here go with the overall size of the microstructured reactor and with its number. 

Another pilot microstructured reactor uses a smart scale-up of the reactor plate dimensions by a factor of 3.3, each for the width and channel length (see Fig. 13). Stacking further plates is here one concept for future production reactors with another tenfold increase in structured area. 

Markowz G, Schirrmeister S, Albrecht J, Becker F, Schiltte R, Caspary KJ, Klemm E (2005) Microstructured reactors for heterogeneously catalysed gas-phase reactions on an industrial scale. Chem Eng Technol 28 459 -64 Muller A, Cominos V, Hessel V, Horn B, Schiirer J, Ziogas A, Jahnisch K, Hillmann V, GroBer V, Jamc KA, Bazzanella A, Rinke G, Kraut M (2005) Fluidic bus system for chemical process engineering in the laboratory and for small-scale production. Chem Eng J 107 205-214 Pennemann H, Watts P, Haswell S, Hessel V, Lowe H (2004) Org Proc Res Dev 8 422... 

In the above-described pChemTec project, a combination of miniplant and micro structured reactor plant equipment is used for the organoborane synthesis as an example for a future production facility for fine chemicals. This approach differs from the usual application of a miniplant as a mediator between laboratory-scale and pilot plant-scale operation. The microstructured reactor plant shown in Figure 4.47, a combination with a typical miniplant set-up, exhibits greater complexity than the miniplant but it nevertheless consumes a much smaller proportion of the volume of the plant set-up. 

The process was performed for many months yielding 700 g of monofluorinated product with a nine-channel microstructured reactor [60]. A continuous 150 h operation was performed without decline of yield or conversion. Even in the scale-out to a 30-channel reador (see Figure 5.27), no loss in performance was noticed. A single feed system distributed the reactants and reagents to the various microchannels. 

Microstructured Mixer-reactors for Pilot and Production Range and Scale-out Issues 89... 

In this chapter, the microstructured devices are introduced underlying their potential benefits for the process industries. The reduced scale facilitates the temperature control giving an opportunity to maintain the temperature within any window required. Enhanced (heat/mass) transfer rates allow control of highly exothermic and hazardous reactions. It also increases production rates and thus reduces the total processing volume. In addition, microreactors can be simply numbered up for large-scale production, avoiding the problem of scale-up of conventional reactors. 

Regular flow patterns are provided by the segmented flow in a single capillary or in multi-channel microreactors. Miniaturized packed-bed microreactors follow the paths of classical engineering by enabling tridde-bed or packed bubble column operation. M ost of the microstructured multiphase reactors are at the research stage. Due to the small reaction volumes th will find their appHcation mainly in small-scale production in the fine chemical and pharmaceutical industries. 

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