(123b) Data Standardization Using an Extensible Mark-up Language (XML) to Estimate Kinetic Parameters for Refinery Processes. Case Study: Hydrocracking

Data standardization using an eXtensible Mark-up
Language (XML) to estimate kinetic parameters for refinery processes. Case
study: Hydrocracking

L.C.
López ¹, J.J. Arias ¹, M.Kraft²,   A.Molina^*1.

¹
Universidad Nacional de
Colombia ? Sede Medellín, Facultad de Minas, Bioprocesos y Flujos reactivos,
Medellín, Colombia

²
University
of Cambridge, Department of Chemical Engineering and Biotechnology, Computational
Modelling Group, Cambridge, United Kingdom.

^*Corresponding author: amolinao@unal.edu.co

Extensible
Mark-up language (XML) was used to standardize kinetic data of refinery
processes. In this work this standardization process is illustrated with
hydrocracking as case study. Hydrocracking is a refinery process used to
convert vacuum gas oils into high-value fuels. With hydrotreatment, it allows processing
of heavy crude oils with high sulfur, nitrogen and metals content. To face the
challenge of the high demand of lighter products such as naphtha, gasoline,
kerosene and light gases, the processing and upgrading of heavy residue has
attracted the attention of the refinery industry. Several kinetic mechanisms [1-8]
have been reported on the hydrocracking literature. These mechanisms use lumps to
represent the large numbers of chemical compounds present in the feed with a
smaller number of pseudocomponents.

One
interesting characteristic of the literature available on crude oil refining,
and particularly on hydrocracking, is that each research proposes an individual
set of kinetic parameters. The data obtained by other groups is normally lost
or, in the best case, only used for comparison. This research looks for a
methodology that helps in the standardization of these data so that more robust
mechanisms can be developed. This paper deals particularly with how eXtensible
Mark-up Language (XML) can be use as the standardization methodology and is
applied to hydrocracking as illustrative case.

To model
hydrotreatment, the mechanism proposed by Martínez et al. [8] was selected as
it has the right complexity level, universality, availability of experimental
data and availability on kinetic parameters to represent the hydrocracking of
Colombian heavy oil. The kinetic parameters originally proposed in [8] were
regressed to obtain a new set that represents industrial data for a Colombian
hydrocracker.   A set of simulations were carried out in the software
Matlab with the same temperature profile, reactor dimensions and catalyst of an
industrial hydrocracking reactor that was approximated as a Packed Bed Reactor
(PBR).

The kinetic
parameter estimation started with the construction of an  open-source database, that includes kinetic
data and experiments from 10 different sources, written using an eXtensible
Mark-up Language (XML). The database includes data previously reported in open
literature, and data from the Hysys hydrotreatment black-box model [9] and
industrial data. The comparison with multiple sources improves the universality
of the model.

Once the
database was completed, the fmincon routine available in the Matlab
Optimization Toolbox was implemented to minimize the mean square error between
the data obtained by the model and the various external source data described
above.

A first
simulation using only industrial data was done to estimate a set of kinetic
parameters.The results show good agreement between the industrial data and the model
with an associated relative error less than 5% for all exit flows of the
reactor.

References

[1]      D. I. Orochko, I. Y.
Perezhigina, S. P. Rogov, M. V Rysakov, G. N. Chernakova, ?Applied over-all
kinetics of hydrocracking of heavy petroleum distillates,? Chem. Technol.
Fuels Oils, vol. 6, no. 8, pp. 561?565, 1970.

[2]       S. Sánchez, M. A. Rodríguez,
J. Ancheyta, ?Kinetic Model for Moderate Hydrocracking of Heavy Oils,? Ind.
Eng. Chem. Res., vol. 44, no. 25, pp. 9409?9413, 2005.

[3]       S. M. Yui, ?Mild
Hydrocracking of Bitumen-Derived Coker and Hydrocracker Heavy Gas Oils:
Kinetics, Product Yields, and Product Propertied,? pp. 1278?1284, 1989.

[4]       M. A. Callejas, M. T.
Martínez, ?Hydrocracking of a Maya Residue. Kinetics and Product Yield
Distributions,? Ind. Eng. Chem. Res., vol. 38, no. 9, pp. 3285?3289,
1999.

[5]       K. Aoyagi, W. C. McCaffrey,
M. R. Gray, ?Kinetics of Hydrocracking and Hydrotreating of Coker and Oilsands
Gas Oils,? Pet. Sci. Technol., vol. 21, no. 5?6, pp. 997?1015, Jan.
2003.

[6]       C. Botchwey, A. K. Dalai,
J. Adjaye, ?Product Selectivity during Hydrotreating and Mild Hydrocracking of
Bitumen-Derived Gas Oil,? Energy & Fuels, vol. 17, no. 5, pp.
1372?1381, Sep. 2003.

[7]       C. Botchwey, A. K. Dalai,
J. Adjaye, ?Kinetics of Bitumen-Derived Gas Oil Upgrading Using a Commercial
NiMo/Al 2 O 3 Catalyst,? vol. 82, no. June, pp. 478?487, 2004.

[8]      J.
Martínez, J. Ancheyta. ?Kinetic model for hydrocracking of heavy oil in a            CSTR involving short term catalyst
deactivation?. Fuel. Vol 100 pp.
193-199, 2012.

[9]      AspenTech,
Aspen Hysys (Versión 8.4) [Software].