Conversion, duty

These expressions relate the terms X, (-i ), Vr, and u. Therefore, tlie fourtli term can be determined if the remaining terms are known. When designing, the size of the reactor needed for a given duty or the extent of conversion in a reactor of given size can be directly obtained. 

If the reactor conversion is changed so as to optimize its value, then not only is the reactor affected in size and performance but also the separation system, since it now has a different separation task. The size of the recycle will also change. If the recycle requires a compressor, then the capital and operating costs of the recycle compressor will change. In addition, the heating and cooling duties associated with the reactor and the separation and recycle system change. 

Figure 5. Pulse flow measurement of the conversion of CO over prereduced (top curves reduction in 5% CO in He at 600°C for 1 h at a flow of 100 mL/60 s.) and as received (bottom curves) La2FeMnOe. Duty cycle 30 s pulse length, 10 min interval, 18-23-s sample delay. Conditions t, decreased or increased in steps catalyst weight, 176 mg and flow, 100 mL/60 s of 5% CO and 5% OsinHe.

The catalyst preparation area supervisor, on-duty control room operator for the catalyst operation, and maintenance superintendent were key sources of information. Their written records and logs were examined in detail. Other personnel that were interviewed included two outside operators, fire brigade members, and associated maintenance employees. During these conversations, special attention was paid to nonverbal signals. The interview process generated several unanswered questions about operational and maintenance procedures that required further study. 

CSTRs in series. The latter is often normalised by dividing by the volume of an ideal PFR required to perform the same duty. Different charts are required for each reaction rate expression. Figure 12 refers specifically to first-order kinetics, but other charts are available in, for instance refs. 17, 18 and 26. Figure 12 re-emphasises many of the points we have made already. In particular, the performance of the N CSTRs in series tends to that of a PFR of the same total volume as N becomes large and the PFR volume required to achieve a certain conversion for a first-order reaction is always smaller than the total volume of any array of CSTRs which perform the same duty. Charts in the form of Fig. 12 are particularly useful when performing approximate design calculations. 

Imagine a first-order reaction taking place in such a system under conditions where rk, i.e. VkjQ, is 10 and R is 5. Using the technique previously adopted in Sect. 5.1 and outlined in Appendix 2, we can readily calculate that this system would achieve 96.3% conversion of reactant. Under these conditions, the recycle reactor volume turns out to be 3.03 times that of an ideal PFR required for the same duty. This type of calculation allows Fig. 14 to be constructed this is similar in form to Fig. 12, but lines of constant for the tanks-in-series model have been replaced by lines of constant recycle ratio for the recycle model. From a size consideration alone, the choice of a PFR recycle reactor is not particularly... 

These relationships are represented in graphical form in Fig. 6.12. This allows us to predict the overall conversions for such systems, or conversions at intermediate points between the individual reactors. These intermediate conversions may be needed to determine the duty of interstage heat exchangers. 

Mr. Gregors intimate friend, the Reverend J. Trist of Veryan, mentioned the exemplary manner in which he had fulfilled all the duties of his Christian pastorate, dispensing to his neighbors both spiritual and temporal benefits, and enlivening the society of his friends by his cheerful and instructive conversation (2). 

The size of the entire monolith converter varies for individual applications (from small close-coupled ones in passenger cars to large ones in heavy-duty trucks) to meet similar space velocities and conversions for differently sized engines. However, cross-sectional channel density around 400 cpsi, diameter... 

Fig. 50. Heavy-duty engine test bench measurements. Dotted lines—measurement of NOx conversion (black) and NH3 slip (gray) solid lines—simulation of NOx conversion (black) and NH3 slip (gray). Reprinted with permission from SAE Paper 2006-01-0468 2006 SAE International.

Native Sodas,—In France, Spain, and other countries where common salt is scarce, or where the duty upon this article is so great os to prevent its conversion into carbonate of soda, plants and alkaline waters are extensively consumedfortkofloda they contain. Besides these two great sources, carbon at of soda also occurs mineralized In some countries, though not in any great quantity, and is generally the residue of the evaporation of alkaline waters. 

These show that a single continuous stirred-tank reactor must always be larger than a batch or tubular plug-flow reactor for the same duty, and for high conversions the stirred tank must be very much larger indeed. If two tanks are used, however, the total volume is less than that of a single tank. Although the detailed calculations... 

Bass, E., Bailey, B., and Jaeger, S., LPG Conversion and HC Emissions Speciation of a Light-Duty Vehicle, SAE Paper No. 932745, Society of Automotive Engineers, Warrendale, Pa., 1993. 

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