Continuous Kinetic Lumping Model

CONTINUOUS KINETIC LUMPING MODEL 11.2.1 Description OF THE Model... 

By using the continuous kinetic lumping model for modeling the kinetics of hydrocracking of heavy oils, a reaction order of 1 is assumed for all the pseudocomponents. Hence, for each pseudocomponent, a reaction rate or reactivity is necessary. Thus, a number of reaction rates are present, which in turn generates a distribution of these rates, as given by Equation 11.17. 

To develop the continuous kinetic lumping model, the next assumptions were made ... 

The continuous kinetic lumping model, in contrast to the discrete lump model, is able to predict the whole distillation curve of hydrocracked product. For instance. Table 11.2 shows predicted product compositions for two cases, five lumps and nine lumps, obtained with Equation 11.9 with the optimized parameter values. In the case of the continuous kinetic lumping model, it allows for predicting the entire boiling point, and the yield of any fraction can be defined at convenience without any other recalculation of parameters that is why results for five and nine lumps are easily generated, while in the case of the discrete lumping model, only results for five lumps are reported, and to obtain information for nine lumps apart from the new parameter estimation, more experiments are indeed necessary. The comparison between the two models can then be only made for five-lumps results. The difference of the predicted product composition with both models compared with the experimental values is small. 

Comparison between Experimental and Predicted Product Compositions using a Discrete Five-Lump Kinetic Model and the Continuous Kinetic Lumping Model (Temperature = 400°C, LHSV = 0.5 h )... 

Traditionally, the dependence of the continuous kinetic lumping model parameters with temperature has been previously reported to be as follows (Khorasheh et al., 2001 Pacheco and Dassori, 2002). For a, a, a, and 5, within a short range of temperature, the following linear dependence has been proposed ... 

Figure 11.13a shows the dependence of parameters of the continuous kinetic lumping model with temperature at three pressures. It is observed that within the range of temperature studied (380°C-420°C), this dependence is linear (Elizalde et al., 2009). 

Elizalde, L, Ancheyta, J. 2011. On the detailed solution and application of the continuous kinetic lumping modeling to hydrocracking of heavy oils. Fuel 90 3542-3550. 

Elizalde, I., Rodriguez, M.A., Ancheyta, J. 2009. Application of continuous kinetic lumping modeling to moderate hydrocracking of heavy oil Appl. Catal. A 365 237-242. 

Modeling of Hydrocracking by Continuous Kinetic Lumping Approach... 

Elizalde, I., Ancheyta, J. 2012. Modeling the simultaneous hydrodesulfurization and hydrocracking of heavy residue oil by using the continuous kinetic lumping approach. Energy Fuels 26 1999-2004. 

Elizalde, L, Rodriguez, M.A., Ancheyta J. 2010. Modeling the effect of pressure and temperature on the hydrocracking of heavy crude oil by the continuous kinetic lumping approach. App/. Catal. A 382 205-212. 

Chapter 11 treats the modeling of hydrocracking by means of the continuous kinetic lumping approach. The model is described in detail in a step-by-step process. 

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