Auxiliary equipment development

Before the details of a particular reactor are specified, the biochemical engineer must develop a process strategy that suits the biokinetic requirements of the particular organisms in use and that integrates the bioreactor into the entire process. Reactor costs, raw material costs, downstream processing requirements, and the need for auxiliary equipment will all influence the final process design. A complete discussion of this topic is beyond the scope of this chapter, but a few comments on reactor choice for particular bioprocesses is appropriate. 

Auxiliary equipment such as oil systems, gears, and control systems shall be tested in the vendor s shop. Details of the auxiliary equipment test shall be developed jointiy by the purchaser and the vendor. 

The 1960s witnessed significant progress in the performance and accuracy of the apparatus. The versatility of the equipment increased as new detectors and auxiliary equipment were developed. 

Freeboard. Under normal operating conditions gas rates somewhat in excess of those for minimum fluidization are employed. As a result particles are thrown into the space above the bed. Many of them fall back, but beyond a certain height called the transport disengaging height (TDH), the entrainment remains essentially constant. Recovery of that entrainment must be accomplished in auxiliary equipment. The TDH is shown as a function of excess velocity and the diameter of the vessel in Figure 6.10(i). This correlation was developed for cracking catalyst particles up to 400 pm dia but tends to be somewhat conservative at the larger sizes and for other materials. 

Engineering design and development. If the operation is an established one, equipment of standard mechanical design can be purchased. The difference in cost between a conventional separator using standard auxiliary equipment and an unconventional separator that requires development and testing can be excessive. 

The estimates of Table XI, except those in the first three rows, are based on very meager amounts of data and therefore are only preliminary approximations. As may be seen in Table XI, the internally cooled converter process, in its present (1947) stage of development, has a space-time yield about two-thirds of that of the fluidized iron catalyst process with about 30% more steel necessary for installing of the converter and its auxiliary equipment. The I.C.C. process is quite versatile in that various types of catalyst, and a variety of operating pressures may be used. The product distribution can be varied, therefore, over a wide range. 

Potential photocatalysts, radiation sources and auxiliary equipment pertinent to the photocatalytic studies developed at the Chemical Reactor Engineering Centre (CREC) using Photo-CREC reactors, ai e reported in this chapter. The discussion about the auxiliary equipment can be relevant, however, to photocatalytic studies in general when other reactor configurations are used. 

The evaluation of photocatalytic reactor performance is closely related to the continuous evaluation and reassessment of lamp operation since lamps experience decay with time of utilization. It is recommended that lamps be calibrated and re-recalibrated frequently to estimate their decay. In addition, it is advised to use some auxiliary equipment in perfonning this task (a) a UVX digital radiometer, (b) a 4D Controls Ltd spectrora-diometer, (c) the Lamp Testing Unit (LTU) developed by Serrano and de Lasa (1997), and (d) a set of tubulai collimators for radiation ti ansmission measurements. 

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