Reactor equipment performance

The second classification is the physical model. Examples are the rigorous modiiles found in chemical-process simulators. In sequential modular simulators, distillation and kinetic reactors are two important examples. Compared to relational models, physical models purport to represent the ac tual material, energy, equilibrium, and rate processes present in the unit. They rarely, however, include any equipment constraints as part of the model. Despite their complexity, adjustable parameters oearing some relation to theoiy (e.g., tray efficiency) are required such that the output is properly related to the input and specifications. These modds provide more accurate predictions of output based on input and specifications. However, the interactions between the model parameters and database parameters compromise the relationships between input and output. The nonlinearities of equipment performance are not included and, consequently, significant extrapolations result in large errors. Despite their greater complexity, they should be considered to be approximate as well. 

This matrix will contain information regarding loading characteristics such as flooding hmits, exchanger areas, pump curves, reactor volumes, and the like. While this matrix may be adjusted during the course of model development, it is a boundary on any possible interpretation of the measurements. For example, distillation-column performance markedly deteriorates as flood is approached. Flooding represents a boundary. These boundaries and nonlinearities in equipment performance must be accounted for. 

The European Reliability Data System An Organized Information Exchange on the Operation of European Nuclear Reactors Nuclear Comprehensive records on equipment failure,frequency, modes, unusual events, and plant production U.S. European nuclear reactor data on equipment performance, repair and maintenance 65. 

Model predictions are caipared with experimental data In the case of the ternary system acrylonitrlle-styrene-methyl methacrylate. Ihe experimental runs have been performed with the same recipe, but monomer feed composition. A glass, thermostat ted, well mixed reactor, equipped with an anchor stirrer and four baffles, has been used. The reactor operates under nitrogen atmosphere and a standard degassing procedure is performed Just before each reaction. The same operating conditions have been maintained in all runs tenperature = 50°C, pressure = 1 atm, stirring speed = 500 rpm, initiator (KgSgOg) 0. 395 gr, enulsifier (SLS) r 2.0 gr, deionized water = 600 gr, total amount of monomers = 100 gr. 

Polymerization was performed in a 100 mL glass reactor equipped with a magnetic stirrer and carried out as semi-batch method. First, the reactor was charged with MAO and then 1-hexene in the certain amount was add. Consequently the system was changol to etiiylene atmosphae system. When reaction medium was saturated with ethylme monoma-. 

Partly with the high stakes in mind, changes have been made in U.S. reactor equipment and operation since the TMI accident to reduce the chance of another accident. The results of these changes are reflected in the predictions of probabilistic risk assessments and by a variety of direct performance indicators. For example, in one measure for U.S. reactors, since the pre-TMI days there has been a reduction of more than a factor of 100 in the number of precursors to potential core damage accidents, as reported by the Nuclear Regulatory Commission (Muley, 1990 Belles et al., 1998). 

No rate enhancement was observed when the reaction was performed under microwave irradiation at the same temperature as in conventional heating [47]. Similar reaction kinetics were found in both experiments, presumably because mass and heat effects were eliminated by intense stirring [47]. The model developed enabled accurate description of microwave heating in the continuous-flow reactor equipped with specific regulation of microwave power [47, 48]. Calculated conversions and yields of sucrose based on predicted temperature profiles agreed with experimental data. 

De Visscher et al. (1996) investigated the sonolysis of benzene and other monocyclic aromatic compounds in aqueous solution by 520 kHz ultrasonic waves. The experiments were performed in a 200-mL glass reactor equipped with a cooling Jacket maintained at 25 °C. At initial benzene concentrations of 3.38 and 0.45 mM, the first-order reaction rates were 0.00171 and 0.02308/min, respectively. 

The oxidation reactions were performed in a 200 cm glass reactor, equipped with gas distributer, condenser, thermometer, measuring and reference electrodes. The mixing frequency of the magnetic stirrer was 1500 min 75 mg Pt or 450 mg Pt-on-alumina catalyst was prereduced in nitrogen atmosphere at 60 °C with 3.67 g or 3.00 g 1-phenylethanol, respectively. The solvent composition was 35 cm water +... 

Catalytic Experiments. Activities were performed in a 1 liter Parr reactor. A typical experiment was performed as follows at a temperature of 100 °C, 100 mg of the catalyst and 1.5 /. wt of (-)-carvone (Aldrich) in n-hexane solution (100 ml) were Introduced in a high pressure Parr reactor equipped with mechanical stirring and automatic temperature control. Before introducing the hydrogen the system was purged 2 or 3 times with Nz> The total hydrogen pressure was 21 atm. The reaction products were analysed by gas chromatography. NMR and Mass Spectrometry and identified as unreacted carvone, carvotanacetone, carvomenthone and three carvomenthol stereoisomers (axial-equatorial, equatorial-equatorial and equatorial-axial). 

Table 7.1 Slow example reaction performed in a reactor equipped with feed-temperature interlock. The behavior of the system under different deviations from normal operating conditions is shown.

The equipment in which reactive polymer processing is carried out, is in fact a chemical reactor. The performance, design, analysis, and control of such reactors have been dealt... 

In addition, a reactor may perform a function other than reaction alone. Multifunctional reactors may provide both reaction and mass transfer (e.g., reactive distillation, reactive crystallization, reactive membranes, etc.), or reaction and heat transfer. This coupling of functions within the reactor inevitably leads to additional operating constraints on one or the other function. Multifunctional reactors are often discussed in the context of process intensification. The primary driver for multifunctional reactors is functional synergy and equipment cost savings. 

Steam reformers equipped with the Pd membranes were developed and have been tested in Japan to produce pure hydrogen from city gas.3 Because of the working principle of the membrane reactor, the performance of this type of steam reformer directly depends on hydrogen permeability of the membranes. This has led us to develop membranes with higher hydrogen permeability. 

The oxidation reactions were performed in a glass batch reactor, equipped with magnetic stirrer (mechanic for L-sorbose oxidation), reflux condenser and thermometer. The reaction conditions are summarized in Table I. Before reaction the catalyst was pre-reduced in situ in a nitrogen atmosphere ( 20 min) with the alcohol reactant in 30-40 ml alkaline water (and dodecylbenzenesulfonic acid sodium salt detergent for water-insoluble reactants). The reactor worked in a mass transfer limited regime, controlled by the air flow rate (7.5-20 cm3min 1) and the mixing rate (1500-1800 min 1). The reactions were followed by GO or HPLC analysis. 

Catalysts Characterization. Following pretreatment of the SAPO molecular sieves, the catalysts were characterized by temperature programmed desorption (TPD) of ammonia and infrared spectroscopy. To assess the acidity of the samples, the desorption of ammonia from the catalysts was performed in a manner similar to that described by van Hooff et. al. [11]. For the ammonia TPD experiments, typically 0.1 gram of the molecular sieve sample was supported on quartz wool inside a 9 mm O.D. quartz reactor equipped with axial thermowell which contacted the top of the... 

In spite of the potential advantages of the use of a catalytic membrane reactor to perform chemical reactions in SC CO2, very few references are available on this topic. The concept was however demonstrated for the hydrogenation of 1-butene using a fluorous derivative of Wilkinson s catalyst [32]. The reaction was successfully performed in a free catalyst membrane reactor equipped with a silica membrane. 

Takaya and Nozaki invented an unsymmetrical phosphin-phosphite ligand, (R,S)-BINAPHOS, which was used in the Rh(l)-catalyzed asymmetric hydroformylation of a wide range of prochiral olefins, with excellent enantioselectivities [120, 155]. A highly crosslinked PS-supported fR,S)-BINAPHOS(257)-Rh(I) complex was prepared and applied to the same reaction (Scheme 3.83) [156]. Using the polymeric catalyst, the asymmetric hydroformylation of olefins was performed in the absence of organic solvents. The reaction of cis-2-butene, a gaseous substrate, provided (S -methylbutanal with 100% regioselectivity and 82% ee upon treatment with II, and CO in a batchwise reactor equipped with a fixed bed. 

In the United States there are at present 61 research and testing reactors with a power of 100 KW or greater, operated by universities, state and national laboratories, and industries in 25 states, most of which can be used for activation analysis ( ). Many analysts work only with long-lived activation products and thus need not be present at the reactor to perform Irradiations. The equipment required for gamma-ray assay s a detector and pulse-height analyzer s is comparable in cost and complexity with that needed for other modern analytical methods. 

A typical reaction procedure was as follows. 10.0 mmol of olefin, 10.0 mmol of oxidant and 10 ml of solvent were charged into a 50 ml three-necked glass reactor equipped with a condenser and a magnetic stirrer. 50 mg of catalyst was added and the mixture was stirred at 60°C. Analysis was performed by gas chromatograph (column OV-1 bonded 0.25mm X 50 m). 

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