Classification operation condition

Before we can proceed with the choice of reactor and operating conditions, some general classifications must be made regarding the types of reaction systems likely to be encountered. We can classify reaction systems into five broad types ... 

The selection of the motor enclosure type involves not only economics but also assessment of two factors area hazard classification and other area operation conditions. 

Figure 52 also shows that the actual recovery curve does not decrease below a certain level. This indicates that a certain amount of material is always recovered to the underflow and bypasses classification. If a comparison is made between the minimum recovery level of solids to the liquid that is recovered, they are found to be equal. Therefore it is assumed that a percent of all size fractions reports directly to the underflow as bypassed solids in equal proportion to the liquid split. Then each size fraction of the actual recovery curve is adjusted by an amount equal to the liquid recovery to produce the "corrected recovery" curve shown in Figure 52. As the Djoc point changes from one application to another, the recovery curves shift, along the horizontal axis. In order to determine a single graph which represents the corrected recovery curve, the particle size of each size fraction is divided by the Dj value and a "reduced recovery" curve can be plotted, as shown in Figure 53. Studies reported by Arterburn have shown that this curve remains constant over a wide range of cyclone diameters and operating conditions when applied to a slurry...

A clear classification of the ideal strategies will help the evaluation of the present room air distribution methods in different operating conditions. It also creates a solid base for the development and promotion of new innovations in the field. 

Minimum filter efficiency The value of a filter s efficiency relating to its performance classification under specified operating conditions. See also Maximum penetrating particle size. 

FPN) The Zone 2 classification usually includes locations where volatile flammable liquids or flammable gases or vapors are used, but which would become hazardous only in case of an accident or of some unusual operating condition. 

Apart from the classification based on the mode of generation of cavities, cavitation can also be classified as transient cavitation and stable cavitation [3]. The classification is based on the maximum radius reached (resonant size), life time of cavity (which decides the extent of collapse) in the bulk of liquid and the pattern of cavity collapse. Generation of transient or stable cavitation usually depends on the set of operating parameters and constitution of the liquid medium. Depending on the specific application under question, it is very important to select particular set of operating conditions such that maximum effects are obtained with minimum possible energy consumption. 

Likelihood of Hazard. The NEC recognizes two distinct levels of hazard probability. Division 1 denotes an environment in which the probability exists that sufficient levels of the hazardous element may always exist, under normal operating condition, as to warrant extreme protections. Whereas, Division 2 denotes an environment where the probability for sufficient levels of the hazardous element to exist, under normal operating conditions, is less likely, and therefore, the extreme protection is not justifiable. Further areas adjacent to Division 1 areas can often constitute classification as Division 2 environments. 

It is noteworthy that the group classification depends not only on the particle but also on the gas properties. Moreover, the above classification is related to the fluidization in the presence of air at ambient conditions. For a different fluid and operating conditions, a powder may appear in a different group. Thus, Figure 3.52 can be helpful in classifying a powder only for ambient conditions and with air as the fluid. 

Because of their important application value, much research and development on the preparation technologies of ultrafine powders has been carried out in the last twenty years and more, and hundreds of preparation methods have been proposed. Since they are not the major topic of this book, neither a description of the classification of the methods nor an introduction to the details of the various methods will be covered here. On the other hand, reaction-precipitation methods generally have a number of advantages such as lower cost, moderate operating conditions, lower equipment requirements, convenience of operation, and normally yield good-performing products etc. thus they occupy an important position among the various methods. 

A theoretical and experimental study of multiplicity and transient axial profiles in adiabatic and non-adiabatic fixed bed tubular reactors has been performed. A classification of possible adiabatic operation is presented and is extended to the nonadiabatic case. The catalytic oxidation of CO occurring on a Pt/alumina catalyst has been used as a model reaction. Unlike the adiabatic operation the speed of the propagating temperature wave in a nonadiabatic bed depends on its axial position. For certain inlet CO concentration multiplicity of temperature fronts have been observed. For a downstream moving wave large fluctuation of the wave velocity, hot spot temperature and exit conversion have been measured. For certain operating conditions erratic behavior of temperature profiles in the reactor has been observed. 

A continuous crystallization process ultimately reaches a steady state, in which the rates of nucleation and growth are constant with time. For a given set of operating conditions, crystal size distribution depends considerably upon the degree to which product classification is practiced. Figures 23 and 24 illustrate schematically the possible extremes between... 

All of these documents stress a requirement for room classifications according to the concentration of non-viable airborne particles at 0.5 pm and larger. The EU GMPs subordinate classification of the various areas applicable to sterile manufacture according a broader based grading system. Grades A to D are defined in terms of a range of independent characteristics such as the concentration of non-viable airborne particles at two sizes in operational and non-operational conditions, the concentration of airborne... 

Table 18-7 has the typical design sizing criteria and operating conditions for a number of applications. It is presented for purposes of illustration or preliminary estimate. Actud thickening and classification performance is dependent on particle-size destribution, specific gravity, sludge bed compaction characteristics, and other factors. Final design should be based on bench scale tests. 

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