Reactors process route

There are a variety of routes currently utilized to fabricate a wide range of hollow capsules of various compositions. Among the more traditional methods are nozzle reactor processes, emnlsion/phase-separation procednres (often combined with sol-gel processing), and sacrificial core techniques [78], Self-assembly is an elegant and attractive approach for the preparation of hollow capsules. Vesicles [79,80], dendrimers [81,82], and block hollow copolymer spheres [83,84] are all examples of self-assembled hollow containers that are promising for the encapsnlation of various materials. 

It is important for the discussion below to distinguish between direct and indirect process routes. Direct carbonation is the simplest approach to carbonate production (or mineral carbonation see Section 14.4) and the principal approach is that a suitable feedstock-for example, serpentine or a Ca/Mg-rich solid residue-is carbonated in a single process step. For an aqueous process this means that both the extraction of metals from the feedstock and the subsequent reaction with the dissolved C02 to form carbonates takes place in the same reactor. 

Comparison of Different Process Routes and Reactor Configurations... 

Processes often differ in terms of the process conditions, e.g. high-pressure and low-pressure processes, or the type of reactor that is used, e.g. gas-phase catalytic reactor or liquid-phase CSTR. These differences should be clearly marked on both the simple block diagrams for each process and the detailed process flowsheets, they often determine which process route is ultimately selected. Many older, established processes were operated under conditions of high pressure or high temperature (mainly in the reactor), whereas the newer processes have often been improved by operation under less severe conditions. 

Software tools are applied in every step of process development. Tools for individual reactor simulations such as computational fluid dynamic simulations are not the topic in this chapter. These tools supply only numerical data for specific defined reactor geometry and defined specific process conditions. A change of parameter would demand a complete recalculation, which is often a very time-consuming process and not applicable to a parameter screening. Methods for reactor optimization by CFD are described in detail in the first volume of this series. Tools for process simulation allow the early selection of feasible process routes from a large... 

Once the process has been defined, attention can then be paid to the unit operations , the reactors, separators, etc. that make up the process route, or flowsheet (Figure 1). This involves the study of ... 

In the present paper Werther s two-phase model for fluidized bed reactors is applied to the synthesis of maleic anhydride as an example of a complex reaction system. Based on experimental data found in the literature two process routes differing in the feedstocks used were investigated. In both cases the model is able to describe the behaviour of the fluid bed reactors including the scale-up effects. 

The MTC process was primarily designed to produce ethylene by operating a MTG type catalyst and process at low pass conversion in a fixed bed reactor. The route was developed by A.E.C.I. in South Aflica who demonstrated the process to pilot plant scale. 

The process route of uranium as nuclear fuel is shown in Fig. 11.7. It begins with processing of uranium ores, from which pure uranium compounds are produced. These may be used in the natural isotopic composition or transformed into other compounds suitable for isotope separation. The next step is the production of fuel elements for the special requirements of reactor operation. Solutions of uranium compounds are applied only in homogeneous reactors. 

Decreasing operation temperature of solid oxide fuel cells (SOFCs) and electrocatalytic reactors down to 800-1100 K requires developments of novel materials for electrodes and catalytic layers, applied onto the surface of solid electrolyte or mixed conducting membranes, with a high performance at reduced temperatures. Highly-dispersed active oxide powders can be prepared and deposited using various techniques, such as spray pyrolysis, sol-gel method, co-precipitation, electron beam deposition etc. However, most of these methods are relatively expensive or based on the use of complex equipment. This makes it necessary to search for alternative synthesis and porous-layer processing routes, enabling to decrease the costs of electrochemical cells. Recently, one synthesis technique based on the use... 

The advances in bioseparation technology need to keep pace with the rate of development of novel bio- or chemocatalytic process routes with revised demands on process technology. The need for novel integrated reactors is also presented. The necessary acceleration of process development and reduction of the time-to-market seem well possible, particularly by integrating high-speed experimental techniques and predictive modelling tools. This is crucial for the development of a more sustainable fine-chemicals industry. 

V. Hessel, Exploring novel processing routes by microstructured reactors, CPAC Satellite Workshops, 2007, Micro-Reactors and Micro-Analytical, March 19-21, 2007, University of Washington Rome Center, Rome, http // www.cpac.washington.edu/Activities/ satellite meetings/Rome%202007/... 

Loewe, H. and Hessel, V. (2006). New approaches to process intensification microstructured reactors changing processing routes. Proceedings of the 2nd Process Intensification and Innovation Conference, Christchurch, New Zealand, 24-29 September. 

Other possible processing routes include the calcia processing route (reaction of zirconium silicate with CaO at 1600 °C, and leaching the calcium silicate formed by treatment with HCl), and the plasma route (thermal dissociation of zirconium silicate in a plasma reactor above 2100 °C, and leaching the glassy silica formed with NaOH). 

Compact process route for reactor grade zirconium production... 

This process route is used for heavy hydrocarbon feedstocks which are not suitable for steam reforming. The range of fuels includes naphtha, heavy fuel oil, crude oil, asphalt, and tar. In the partial oxidation reactor, or gasifier, the feedstock is burnt with a limited supply of oxygen in the presence of steam. The basic reaction is... 

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