Imperial College London

Prof. Sandro Macchietto

Faculty of EngineeringDepartment of Chemical Engineering

Professor of Process Systems Engineering



+44 (0)20 7594 6608s.macchietto Website




Miss Nazma Mojid +44 (0)20 7594 3918




ACEX 507ACE ExtensionSouth Kensington Campus






BibTex format

author = {Coletti, F and Macchietto, S},
title = {Multi-scale modelling of refinery pre-heat trains: Effect of crude fouling on energy recovery, carbon emission and economics},
year = {2009}

RIS format (EndNote, RefMan)

AB - Pre-heat trains (PHTs) in crude distillation units are complex networks of heat exchangers used to recovery up to 60-70% of all the energy necessary for primary fractionation. Efficiency of the train is severely impaired by fouling, the deposition of unwanted material on the thermal surfaces. Economic losses related to this problem was estimated of the order of 1.2 billion dollars p.a. in the United States alone when the price of oil was significantly cheaper. Maintenance issues as well as health and safety hazards are also related to this problem that oil refineries have been facing for decades. Experimental evidences show that fouling rates are function of crude composition and process conditions, namely temperature and velocity. It has also been demonstrated that, for a given crude composition, threshold conditions of temperatures and velocities exist below which no fouling occurs. However, the complex chemical and physical mechanisms underlying fouling deposition are still poorly understood. For this reason, both design and monitoring techniques, based on highly empirical fouling factors, have substantially not changed over the past 40 years. To tackle this long standing problem in a systematic way, a large scale interdisciplinary research project, CROF (for CRude Oil Fouling) has been established. The project, coordinated in 8 subprojects, aims at providing a platform to investigate fundamental parameters leading to deposition, to provide a framework for predicting deposition and avoiding it by design and to formulate methods for mitigation. Within the CROF framework, a multi-scale, first principles model for a shell and tube heat exchanger was developed and validated against data from an ExxonMobil refinery. The model is dynamic, distributed and accounts for local variation of physical properties. Several scales of investigation are considered simultaneously. At the tube level, the interactions between operating conditions and fouling are captured by coupling
AU - Coletti,F
AU - Macchietto,S
PY - 2009///
TI - Multi-scale modelling of refinery pre-heat trains: Effect of crude fouling on energy recovery, carbon emission and economics
ER -