Separation equipment, design procedure

Equipment design procedures for separation operations require phase enthalpies and densities in addition to phase equilibrium ratios. Classical thermodynamics provides a means for obtaining all these quantities in a consistent manner from P-v-T relationships, which are usually referred to as equations of state. Although a large number of P-v-T equations have been proposed, relatively few are suitable for practical design calculations. Table 4.2 lists some of these. All the equations in Table 4.2 involve the universal gas constant R and, in all cases except two, other constants that are unique to a particular species. All equations of state can be applied to mixtures by means of mixing rules for combining pure species constants. 

Shortcut Equipment Design Methods tend to become buried in design procedures, even computer-based ones. Therefore they often become part of the mix and don t stand free as separate entities. This is not bad. These methods need to be placed wherever they are useful. However, it is also good to draw them out since many everyday problems can be solved with undiluted shortcuts. 

Sizing, 451, 453, 455, 459, 462 Sonic flow, 461 Types, illustrations, 411-421 Rupture disk, liquids, 462, 466 Rupture disk/pressure-relief valves combination, 463 Safely relief valve, 400 See Relief valve Safety valve, 400, 434 Safety, vacuum, 343 Scale-up, mixing, 312, 314—316 Design procedure, 316-318 Schedules/summaries Equipment, 30, 31 Lines, 23, 24 Screen particle size, 225 Scrubber, spray, 269, 270 Impingement, 269, 272 Separator applications, liquid particles, 235 Liquid particles, 235 Separator selection, 224, 225 Comparison chart, 230 Efficiency, 231... 

Each potential split selected at the step 3 can be the subject of a design procedure, which can be of shortcut type or based on rigorous simulation. For some particular or innovative separators the sizing algorithm might not be available, but this fact should not hinder the procedure. It suffices that the feasibility of the task can be guaranteed by an equipment supplier, or this is put on the list of equipment for which suppliers are searched. 

If the hierarchical means-ends analysis synthesis procedure is applied to the methyl acetate problem, the task identification, task integration, and equipment design stages are kept completely separate. Following the property-difference hierarchy, an identity-changing reaction task (Task A) is identified first, as before. When examining the differences between the result of this reaction task application and the product methyl acetate and by-product water destinations,... 

Table 2. Short-cut design procedure for separation equipment...

The goal of the design procedure is to determine the number of theoretical stages (or number of transfer units) needed for a separation, the height of a separation column, the capacity of mass transfer equipment, and the diameter of a separation column. These... 

Albertson, O. E., Design procedures for industrial secondary clarifiers . Paper B2.5, AES Seminar and Expo, System Approach to Separation and Filtration Process Equipment, Chicago, Illinois USA, May 3-6, 1993, paper pubhshed in Advances in Filtration and Separation Technology, Vol. 7, American Filtration Society, Kingwood, Texas, April, 198-203 (1993)... 

The next important step in designing a reactor is the choice of the reactor type. Among many different alternatives for chanical reactors, in this part of the book, we will focus on three major systems due to the breadth of the processes that these systems are used The packed-bed reactor, the fluidized-bed reactor, and gas-liquid(-solid) contact equipment. We have dedicated a separate chapter for each of these systems and elaborated on their design procedure through extensive examples. 

On a practical level the whole analysis is performed at the semimicro level. This means that sample sizes are in the range of 10 mg and solutions are of the order of 1-2 ml in volume. Special equipment is required to handle low volumes of reagent solutions and to avoid serious losses in separative and transfer procedures. The separation of precipitates is performed by centrifugation and decantation, and heating is achieved in specially designed test tube heating blocks. 

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