Equipment design
For the continuous biodiesel (methyl palmitate) production, an ideal “plug-flow" type reactor was selected from the “Object Palette” of Aspen HYSYS, by analogy of behavior with the ideal stirred batch reactor with constant density (Levenspiel, 1998, 2004; Fogler, 2005) employed in the kinetic study of Cheng et al. (2004). This procedure is based on the concept of existing equivalence between the time of reaction in a ideal stirred batch reactor and the spatial time in a ideal plug flow reactor, when density of the reacting mix maintains constant (Levenspiel, 1998, 2004).
Dimensions of the reactor (diameter and length) were defined equal the corresponding to the PPR tubular reactor. Two mixers were installed at the reactor inlet to provide the reactants streams with the prefixed molar relation (1:10) and catalysts concentration (0.125 mol NaOH/kg oil) using the “Set” tool of Aspen HYSYS (Figure 2). Negligible pressure loss in the equipments were considered.