Processing method selection

Separation of a fat or oil from its source material can be accompHshed by several different methods. Selection of an extraction process is based on (/) obtaining oil substantially undamaged and relatively free of undesirable impurities, (2) achieving the highest practical yield, and (J) obtaining the maximum economic return on the oil and coproducts. 

Whereas Hquid separation method selection is clearly biased toward simple distillation, no such dominant method exists for gas separation. Several methods can often compete favorably. Moreover, the appropriateness of a given method depends to a large extent on specific process requirements, such as the quantity and extent of the desired separation. The situation contrasts markedly with Hquid mixtures in which the appHcabiHty of the predominant distiHation-based separation methods is relatively insensitive to scale or purity requirements. The lack of convenient problem representation techniques is another complication. Many of the gas—vapor separation methods ate kinetically controUed and do not lend themselves to graphical-phase equiHbrium representations. In addition, many of these methods require the use of some type of mass separation agent and performance varies widely depending on the particular MSA chosen. 

Most processing methods involve flow in capillary or rectangular sections, which may be uniform or tapered. Therefore the approach taken here will be to develop first the theory for Newtonian flow in these channels and then when the Non-Newtonian case is considered it may be seen that the steps in the analysis are identical although the mathematics is a little more complex. At the end of the chapter a selection of processing situations are analysed quantitatively to illustrate the use of the theory. It must be stressed however, that even the more complex analysis introduced in this chapter will not give precisely accurate... 

The TA methods described so far can be evaluated in terms of their focus on different aspects of the human-machine interaction. To facilitate the process of selection of appropriate TA methods for particular applications. Figure 4.14 describes ten criteria for evaluation. These criteria are in terms of the usability of the methods for the following applications ... 

Spent Zirflex Process Decladdent. The basic perceived need is to devise an3 develop a simple process for selective and efficient removal of plutonium (and 21 1Am) from spent Zirflex process decladdent solution. To satisfy this need, it may be necessary--or prove beneficial—to determine, by appropriate physiochemical methods, the nature of the plutonium (and americium) species in the decladding solution. Availability of a satisfactory transuranium removal scheme may be one of the key factors in devising an alternative to storage in expensive double-shell tanks for spent Zirflex process solution at the Hanford site. 

Sterilization of the finished drug delivery formulation is an important consideration often overlooked in the early design of lactide/glycolide delivery systems. Aseptic processing and terminal sterilization are the two major routes of affording an acceptably sterile product. Both of these methods are suitable for products based on lactide/glycolide polymers if proper care is exercised in processing or selection of the treatment procedures. 

Flotation is certainly the major separation method based on the surface chemistry of mineral particles. It is, however, not the only method. Selective flocculation and agglomeration may be mentioned as other methods used commercially to a limited extent. The former is for hematite, while the latter is for coal and finely divided metallic oxide minerals. Both processes use the same principles as described for flotation to obtain selectivity. In selective flocculation, polymeric flocculants are used. The flocculants selectively adsorb on the hematite, and the hematite floes form and settle readily. Thereby separation from the sili-... 

The problems relating to mass transfer may be elucidated out by two clear-cut yet different methods one using the concept of equilibrium stages, and the other built on diffusional rate processes. The selection of a method depends on the type of device in which the operation is performed. Distillation (and sometimes also liquid extraction) are carried out in equipment such as mixer settler trains, diffusion batteries, or plate towers which contain a series of discrete processing units, and problems in these spheres are usually solved by equilibrium-stage calculation. Gas absorption and other operations which are performed in packed towers and similar devices are usually dealt with utilizing the concept of a diffusional process. All mass transfer calculations, however, involve a knowledge of the equilibrium relationships between phases. 

Franz et al. [42] reviewed these techniques completely, along with statistical screening techniques and other experimental methods, with an excellent list of publications. A few selected publications from the recent literature demonstrate the wide variety of formulation and processing problems to which these techniques can be applied and the varying methods selected for optimization. 

The ability to precipitate nanoparticles controllably from a dispersion is required for most post-processing methods, including cleaning [11, 12] and size-selective... 

As discussed in Chapter 1, analysis involves the determination of the composition of a material, i.e. the identification of its constituent parts and in many cases how much of each is present and, sometimes, in what form each is present. This chapter describes the process of selecting a suitable analytical method to carry out such determinations and how to check that the procedure selected is adequate for the job in hand. Before starting work on a sample, it is vital to enquire why the analysis is being done and what will happen to the result(s) and what decisions will be taken based on the constituent parts identified and the numerical values obtained. It is essential that the requirements of the customer, internal or external, are fully understood. Which property needs to be measured (the measurand) For example, is it the total amount of iron in a tablet that is required or the amount extracted into stomach acid simulant ... 

This section describes 14 tasks required for compliance with the PSM Rule regardless of the PrHA method selected. The sequence of these tasks is shown in Figure 3.1. This figure also indicates where process safety information (PSI) requirements fit into PrHA tasks, and what documents are generated as a result of each task. Concepts common to all PrHA methods are also discussed. 

TASK d estimate the manpower required and develop a staffing plan. The manpower required to conduct a PrHA depends on many factors, including the review method selected, the training and experience of the review team, the extent and complexity of the process, its instrumentation and controls, and whether the process is a procedure-oriented operation (such as a batch reaction) or a continuous operation (such as petroleum refining). 

Edwards and Lawrence (1993) have presented a list of sixteen chemical and physical properties and process parameters which are available at the process route selection stage (Table 5). Seven of these sixteen parameters were included to their index method (PUS). The selected parameters concentrate very much on the chemical process route and chemistry. They have also tested their selection by an expert judgement, which gave support to their work (Edwards et al., 1996). 

DESIGN CONSIDERATIONS IN THE SELECTION OF PROCESSING METHODS FOR SOFCS... 

Measurement devices, accuracy of, 20 679 Measurement method selection, in industrial hygiene, 14 216-217 Measurements, in minerals recovery and processing, 16 664... 

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