ISSN:
0001-1541
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
A model for a pilot-scale chemical vapor infiltration (CVI) reactor in which multiple substrates are densified simultaneously by carbon deposition from a pyrolyzing hydrocarbon is presented. Kinetic expressions and parameters and transport properties for carbon deposition from propylene determined from experimental studies and a single substrate CVI model are incorporated into the pilot reactor model. The two-dimensional transport equations for heat, mass and momentum transfer are solved for the entire reactor to simulate the effects of varied operating conditions on substrate densification throughout the reactor during the CVI process. Of the conditions simulated, the reactor temperature was found to have the most significant impact on both the uniformity of densification and the process time required. As the temperature increased, the uniformity of densification decreased and the time at which pore blockage at the outer surface occurred was shortened. Increasing the hydrocarbon feed concentration shortened the process time, but did not affect the final level of densification, while the feed rate only affected CVI at intermediate times. Comparison between experimental pilot reactor results and model predictions were satisfactory at short and long times, but agreement was less satisfactory at intermediate times.
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/aic.690390711
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