A reaction engineering approach to the analysis of fouling

✍ Scribed by W.R. Paterson; P.J. Fryer

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 453 KB
• Volume: 43
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(88)85166-2

✦ Synopsis

Employing Fig. 1 to evaluate the derivatives in eqs ( 6) and (8), activation energies can be calculated under the assumption that the derivatives of C, and T, are very small. This is a reasonable assumption for transport-controlled reactions. Values at 300,450,600 and 800°C are collected in Table 1. In all cases we have assumed that the surface temperature is 50°C below the fluid temperature, a typical value. Obviously, the magnitudes of the activation energies shown in Table 1 depend on this assumption. Nevertheless, it is evident that, if heat transfer controls with an endothermic reaction, high activation energies are possible. Decisions concerning transport control for endothermic reactions cannot be routinely made based on measured activation energies. Equation ( 8) demonstrates that the variation of the heat of reaction with temperature and the fluid temperature must be considered.

For the case where fluid-particle mass transfer controls, Table 1 shows that activation energies in the usually quoted range of O-12 kJ/mol are obtained.