Parallel production system

Lopez, F., The Parallel Production System, Ph.D. thesis, University of Illinois at Urbana-Champaign, 1987. 

An example of a parallel reaction system occurs in the production of ethylene oxide ... 

An example of such recychng in a parallel reaction system is in the Oxo process for the production of C4 alcohols. Propylene and synthesis gas (a mixture of carbon monoxide and hydrogen) are first reacted to ra- and isobutyraldehydes using a cobalt-based catalyst. Two parallel reactions occur ... 

Batchwise operating three-phase reactors are frequently used in the production of fine and specialty chemicals, such as ingredients in drags, perfumes and alimentary products. Large-scale chemical industry, on the other hand, is often used with continuous reactors. As we developed a parallel screening system for catalytic three-phase processes, the first decision concerned the operation mode batchwise or continuous. We decided for a continuous reactor system. Batchwise operated parallel sluny reactors are conunercially available, but it is in many cases difficult to reveal catalyst deactivation from batch experiments. In addition, investigation of the effect of catalyst particle size on the overall activity and product distribution is easier in a continuous device. 

Multiple reactions in parallel producing by products. After the reactor type is chosen for parallel reaction systems in order to maximize selectivity or reactor yield, conditions can be altered further to improve selectivity. Consider the parallel reaction system from Equation 5.66. To maximize selectivity for this system, the ratio given by Equation 5.67 is minimized ... 

Animal welfare is an issue that is, at the moment, subject to these kinds of differentiation regarding standards and assurance schemes (Roux and Miele, 2005). A number of initiatives have been taken both within and in parallel to organic production systems, all with the aim of improving farm animal welfare, but with rather diverse standards and expectations. 

A parallel reactor system for liquid-liquid phase reactions such as oxidation reactions with H202 at ambient pressure was reported from hte Aktiengesellschaft. If compared with other chemistries, rather mild-reaction conditions (ambient pressure, moderate temperature) are often applied in liquid-phase oxidation for fine chemical production with terminal oxidants that can be dosed as liquids (e.g., aqueous H202 or organic peroxides). The reaction that was investigated was the partial oxidation of... 

When selectivity and yield of a given product need to be maximized, the design issues become more complicated. While rninimum T is frequently desired, it is usually more important to obtain maximum selectivity to a desired product and niinimiim selectivity to undesired products. For simple series and parallel reaction systems, we can fairly easily summarize the choices. 

In terms of criteria for the approval of private certification bodies, the EU regulation requires compliance to Annex 3 of the regulation in addition to ISO/IEC Guide 65. Annex 3 contains requirements not included in ISO Guide 65 such as parallel production. This format is similar to the IFOAM system with specific accreditation criteria that are not covered in the ISO guide. The USA and Japan have each developed distinct requirements. Beyond this, some countries such as India and Australia (in draft requirements) have chosen to base their criteria on IFOAMs (Commins 2003). 

Products with less demand, such as those used in diagnosis, are developed in small-scale systems such as T-flasks, rollers, and hollow-fiber bioreactors (Kretzmer, 2002). The reduced size of these production systems makes it possible to operate various units in parallel to obtain different products. A small increase in scale can be reached by the multiplication of units. 

In a parallel reaction network of first-order reactions, the selectivity does not depend upon reaction time or residence time, since both products are formed by the same reactant and with the same concentration. The concentration of one of the two products will be higher, but their ratio will be the same during reaction in a batch reactor or at any position in a PFR. The most important parameters for a parallel reaction system are the reaction conditions, such as concentrations and temperature, as well as reactor type. An example is given in the following section. 

Both the new hydrogen production systems and the devices to convert that hydrogen into services that consumers will freely purchase must be developed in parallel. Neither serves any purpose without the other. 

Description The CATOFIN reaction system consists of parallel fixed-bed reactors and a regeneration air system. The reactors are cycled through a sequence consisting of reaction, regeneration and evacuation/purge steps. Multiple reactors are used so that the reactor feed/product system and regeneration air system operate in a continuous manner. 

Parallel production of many beads of one type. Although the beads are the miniaturized entities of the system, their bulk processing does not require miniaturization. 

When the catalyst is immobilized within the pores of an inert membrane (Figure 25.13b), the catalytic and separation functions are engineered in a very compact fashion. In classical reactors, the reaction conversion is often limited by the diffusion of reactants into the pores of the catalyst or catalyst carrier pellets. If the catalyst is inside the pores of the membrane, the combination of the open pore path and transmembrane pressure provides easier access for the reactants to the catalyst. Two contactor configurations—forced-flow mode or opposing reactant mode—can be used with these catalytic membranes, which do not necessarily need to be permselective. It is estimated that a membrane catalyst could be 10 times more active than in the form of pellets, provided that the membrane thickness and porous texture, as well as the quantity and location of the catalyst in the membrane, are adapted to the kinetics of the reaction. For biphasic applications (gas/catalyst), the porous texture of the membrane must favor gas-wall (catalyst) interactions to ensure a maximum contact of the reactant with the catalyst surface. In the case of catalytic consecutive-parallel reaction systems, such as the selective oxidation of hydrocarbons, the gas-gas molecular interactions must be limited because they are nonselective and lead to a total oxidation of reactants and products. For these reasons, small-pore mesoporous or microporous... 

However, approximate treatment is possible. Ikeda and Tashiro (19) report an optimization of catalytic reactions in fluid beds. They And that the maximum yield of the intermediate product decreases, and that the optimum contact time increases for first-order consecutive and parallel reaction systems if contact efficiency in the reactor decreases. They also showed the most economical equilibrium activity and the optimal size distribution of catalyst. 

When we consider the function of most supervised models of learning, it is evident that their common objective is to recognize patterns. They do so by processing in parallel the many different features that are available as input. Unlike production system models, connectionist models are influenced by the entire collection of features, not the presence or absence of a particular one. 

Products/technologies The company sells the CombiTec parallel synthesis system, an organic chemical synthesizer that includes a robotic sample processor, and reaction blocks of 8-56 chambers. Other products include the TRAC system for high-throughput screening with more than 100 microplates the GENESIS Series Robotic Sample Processor (RSP) fully automated microplate-based systems and the Cavro RSP 9000 Robotic Sample Processor (XYZ module). 

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