Parameter estimation of a six-lump kinetic model of an industrial fluid catalytic cracking unit

Abstract

In this work a simulation of detailed steady state model of an industrial fluid catalytic cracking (FCC) unit with a newly proposed six-lumped kinetic model which cracks gas oil into diesel, gasoline, liquefied petroleum gas (LPG), dry gas and coke. Frequency factors, activation energies and heats of reaction for the catalytic cracking kinetics and a number of model parameters were estimated using a model based parameter estimation technique along with data from an industrial FCC unit in Sudan. The estimated parameters were used to predict the major riser fractions; diesel as 0.1842 kg-lump/kg-feed with a 0.81% error while gasoline as 0.4863 kg-lump/kg-feed with a 2.71% error compared with the plant data. Thus, with good confidence, the developed kinetic model is able to simulate any type of FCC riser with six-lump model as catalyst-to-oil (C/O) ratios were varied and the results predicted the typical riser profiles.

A Novel Method to Investigate the Activity Tests of Fresh FCC Catalysts: An Experimental and Prediction Process from Lab Scale to Commercial Scale

“…Due to the complex hydrodynamics and mixture, the lumping kinetic model has gained acceptability in description of an industrial FCC unit. For instance, the six lumped kinetic model has a feed, and five products, consisting of diesel, gasoline, liquefied petroleum gas (LPG), dry gas, and coke, adequately represent the product distribution [16,17,19]. If all products deem directly from the cracking of the feedstock oil, the reaction rate or the kinetic model equations can be expressed as fellow:…”

“…The activity of moderate deactivation deviated from that of E-Cat. Actually, many FCC E-Cat have conversion, about 72~76% [9,11,17]. Therefore, it is necessary to modify the hydrothermal conditions and the "Reference conversion" or "Reference catalyst" to fit the conditions of commercial units.…”

“…Evaluation of fresh FCC catalysts can require expensive laboratory or actual field tests, where feedstock disturbances or market demands could make the evaluation difficult. The first step is to assess the potential in cracking activity and yield selectivity, either for a standalone catalyst or for co-catalysts [15], and hydrothermal effect and metals deposition are two main factors that influence the catalyst deactivation for commercial FCC units [15][16][17][18]. Hydrothermal deactivation represents the equilibrium activity as a function of a regenerator bed temperature and regeneration bed flue gas water partial pressure, while metal deactivation reflects the influence of metal content on commercial equilibrium catalyst (E-Cat).…”

Development of Fluid Catalytic Cracking Distributed Simulator Based on IEC 61499

“…Model matematik produk FCC dapat dimodelkan berdasarkan jumlah komponen yang digambarkannya. Parameter reaksi perengkahan pada FCC diestimasikan dalam 6 komponen [4]. Keenam komponen tersebut yaitu gas oil (a), diesel oil (b), gasoline (c), liquid petroleum gas (LPG) (d), light gas (e), dan coke (f) seperti terlihat pada Gambar 3.…”

Online Optimization of Fluid Catalytic Cracking Process via a Hybrid Model Based on Simplified Structure-Oriented Lumping and Case-Based Reasoning

“…The traditional lumping kinetics usually categorizes oil composition according to boiling point, which hardly reflect the variation of feed composition and thus cannot be extrapolated to other raw materials. Meanwhile, the molecular composition of lumps may change greatly during the whole transformation process, which may cover the real reaction kinetic process, and few details of molecular composition contained in lumps, enabling it to predict the yield but not the properties of the products, which is the main limitation for its application. − With the development of molecular characterization of oil products, , molecular description, and computing technology, a new petroleum refining technology along with refining molecular management has emerged, which is more refined, more intelligent, and upgraded to the molecular level. The core of the refining molecular management technology is a molecule-level mechanism model.…”