This work presents the methodology to develop, validate, and apply a predictive model for an integrated fluid catalytic cracking (FCC) process. We demonstrate the methodology using data from a commercial FCC plant in the Asia Pacific with a feed capacity of 800 000 tons per year. Our model accounts for the complex cracking kinetics in the riserÀregenerator with a 21-lump kinetic model. We implement the methodology with Microsoft Excel spreadsheets and a commercial software tool, Aspen HYSYS/ Petroleum Refining from Aspen Technology, Inc. The methodology is equally applicable to other commercial software tools. This model gives accurate predictions of key product yields and properties given feed qualities and operating conditions. In addition, this work presents the first lumped FCC kinetic model integrated with a gas plant model in the literature. We validate this work using 6 months of plant data. We also perform several case studies to show how refiners may apply this work to improve the gasoline yield and increase unit throughput. A key application of the integrated FCC model is to generate DELTAÀBASE vectors for linear programming (LP)-based refinery planning to help refiners choose an optimum slate of crude feeds. DELTAÀBASE vectors quantify changes in FCC product yields and properties as functions of changes in feed and operating conditions. Traditionally, refiners generated DELTAÀBASE vectors using a combination of historical data and correlations. Our integrated model can eliminate guesswork by providing more robust predictions of product yields and qualities. This work differentiates itself from previous work in this area through the following contributions: (1) detailed models of the entire FCC plant, including the overhead gas compressor, main fractionator, primary and sponge oil absorber, primary stripper, and debutanizer columns, (2) process to infer molecular composition required for the kinetic model using routinely collected bulk properties of feedstock, (3) predictions of key liquid product properties not published alongside previous related work (density, ASTM D86 distillation curve, and flash point), (4) case studies showing industrially useful applications of the model, and (5) application of the model with an existing LP-based planning tool.

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This work presents a model for the rating and optimization of an integrated catalytic reforming process with UOP-style continuous catalyst regeneration (CCR) using Aspen HYSYS/Petroleum Refining. The model relies on routinely monitored data, such as American Society for Testing and Materials (ASTM) distillation curves, paraffin–napthene–aromatic (PNA) analysis, and operating conditions. We use a lumped kinetic network with 64 species over a broad C1–C14 range. This network can represent the key dehydrogenation, dehydrocyclization, isomerization, and hydrocracking reactions that typically occur with petroleum feedstock. The lumped kinetic scheme also allows us to make accurate predictions of benzene, toluene, ethylbenzene, and xylenes (BTEX). In addition, this work accounts for the coke deposited on the catalyst and the associated catalyst regeneration. We implement the hydrogen recycle and product recontacting sections as separate unit operations connected to the CCR reformer model. In addition, we include rigorous tray-by-tray simulation models for primary product recovery. We validate this model using 6 months of plant data from a commercial CCR reforming process handling a feed capacity of 1.4 million tons per year in the Asia Pacific. The validated model predicts key process yields and aromatic yields to within an average absolute deviation (AAD) of 1%. In addition, the model predicts liquid petroleum gas (LPG) composition to within 2.0% AAD. We also present several industrially useful case studies that display common interactions among process variables, such as feed composition, reaction temperature, space velocity, and hydrogen/hydrocarbon ratio (H2/HC). These case studies accurately quantify the effect of key process variables on the process performance and demonstrate the model applications for improving energy efficiency and optimizing the reformer performance for chemical feedstock production. This work differentiates itself from the reported studies in the literature through the following contributions: (1) detailed kinetic model that accounts for coke generation and catalyst deactivation, (2) complete implementation of a recontactor and primary product fractionation, (3) feed lumping from limited feed information, (4) detailed procedure for kinetic model calibration, (5) industrially relevant case studies that highlight the effects of changes in key process variables, and (6) application of the model to refinery-wide production planning.