Influence of Operating Conditions

The previous discussion pointed out that various material properties have a more or less strong influence on particle formulation in spray fluidized beds. Process conditions, such as the spraying rate, gas temperature, or the mass flow rate of the fluidization gas, can also very significantly affect the properties of the resulting particles. This aspect will be illustrated in the present section by means of selected examples. 

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Influence of operating conditions This concerns the temperature, the pressure and the residence time. The more severe the conditions are, the harder is the coke produced. 

Influence of operating conditions on ignition and extinction of reactions. 

M. V. Williams, H. R. Kunz, and J. M. Fenton. Operation of Nafion(R)-based PEM fuel cells with no external humidification Influence of operating conditions and gas diffusion layers. Journal of Power Sources 135 (2004) 122-134. 

Rivas, F., Kolaczkowski, S., Beltran, F., and McLurgh, D., Hydrogen peroxide promoted wet air oxidation of phenol influence of operating conditions and homogeneous metal catalysts, ]. Chem. Technol. Biotechnol., 74(5), 390-398, 1999. 

Rodriguez SM, Galvez JB, Rubio MIM, Ibanez PF, Gernjak W, Alberola IO, Treatment of chlorinated solvents by Ti02 photocatalysis and photo-Fenton influence of operating conditions in a solar pilot plant. Chemosphere 2005 58 391-8. 

Fig. 39. Influence of operating conditions on axial gas diflusivity (after Bai, 1991).

B. Radial Distribution of Heat Transfer Coefficients 1. Influence of Operating Conditions... 

Studying the influence of operating conditions on the MWD of polypropylene obtained with three-component catalytic systems. Combs et al. observed that it narrows at high monomer concentrations or at low conversions, especially for low monomer concentrations. 

P. Contal, J. Simao, D. Thomas, T. Frising, S. Call, J.C. Appert-Collin, D. Berner, Clogging of fibre filters by submicron droplets. Phenomena and influence of operating conditions, Aerosol Science, vol. 35, 263-278, 2004. 

Most of the research reported in the literature was oriented towards analyses of product distribution, influence of operating conditions and reaction mechanisms. Recently, spectroscopic characterization of coke deposits formed on Y-zeolite catalysts was reported (13,14), and Stocker et al presented regeneration studies of the EMT catalyst, by heating in air up to 600°C (15). 

Yoshioka, S. Urushibata, H. Superiority of Li2C03/Na2C03 electrolyte in molten carbonate fuel cells. I. Influence of operation conditions on polarization behavior. Denki Kagaku 1996, 64 (8), 909-914. 

Table 3 presents the main textural properties of the supports. It can be seen that the influence of operating conditions is important. Surface areas (sbet) actually vary from 15 to 82 m /g and even if porous volumes are less scattered, the pore distributions are really diversified. 

Thiering R, Dehghani F, Dillow A, Foster NR. The influence of operating conditions on the dense gas precipitation of model proteins. J Chem Technol Biotechnol 2000 75 29 1. 

The objectives of the catalytic reforming of naphtha are to increase the naphtha octane number (petroleum refination) or to produce aromatic hydrocarbons (petrochemistry). Bifunctional catalysts that promote hydrocarbon dehydrogenation, isomerization, cracking and dehydrocyclization are used to accomplish such purposes. Together with these reactions, a carbon deposition which deactivates the catalyst takes place. This deactivation limits the industrial operation to a time which depends on the operational conditions. As this time may be very long, to study catalyst stability in laboratory, accelerated deactivation tests are required. The knowledge of the influence of operational conditions on coke deposition and on its nature, may help in the efforts to avoid its formation. 

This paper reports first results of research and development work to achieve nitrogen oxide reduction under lean diesel exhaust gas conditions. Much attention is paid to the influence of operation conditions on catalyst performance. A major part of the paper deals with the influence of the hydrocarbon component, the hydrocarbon concentration and the HC/NO ratio on the activity of a special developed platinum based catalyst. Other aspects discussed are a spectroscopic characterization and a selectivity study. A hypothesis of a "dual-site" reaction mechanism for NOx-reduction in lean diesel exhaust gas precious metal based catalyst is established. Finally, first promising results on the performance of the catalyst system in a vehicle dynamometer test are given. 

Sanchez, L. Sanchez, R Carmona, M. de Lucas, A. Rodriguez, J.F. Influence of operation conditions on the microencapsulation of RCMs by means of suspension-like polymerization. Colloid Polym Sci 286 (2008) 1019-1027. 

According to activated sludge are able to accumulate large amounts of PHB when cultivated under alternation of feast and famine of external substrate (acetate). The yield of PHB production by this crdture was up to 50% of its dry weight, which is comparable with the value referred above for the cultures cultivated under microaerophilic-aerobic conditions. The influence of operating conditions, namely frequency of feeding and the ratio between the substrate and initial biomass concentration on PHA production was evaluated. The quality of polymer produced under these conditions was not determined. 

Franke, J. and Mersmann, A. (1995) Influence of operational conditions on the precipitation process. Chemical Engineering Science, 50, 1737-1753. 

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