Papers presented to the 11th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 20-23 July 2015.
Crude oil fouling studies generally focus on the thermal
impact of organic deposits. The hydraulic limit given by
pressure drop is, however, frequent cause of shutdowns and
cleaning. Inorganic matter is often found in deposit analysis,
but ignored in most studies. A case study is presented based on
published plant data from the Esfahan Refinery (Iran). A
detailed thermo-hydraulic model of heat exchangers
undergoing fouling, together with the available data and
reasonable assumptions, is applied to study the exchanger most
affected by fouling. Novel modifications are made to: i) capture
the effect of inorganics on the deposit conductivity; and ii) use
pressure drop measurements, instead of temperature, to fit key
fouling parameters. Good agreement is obtained between model
and plant data. This demonstrates the need and benefit of
considering fouling layer composition and both temperature
and pressure drop data in the fitting of model parameters and
interpretation of plant data. The potential of using such a model
for early detection of operative problems is highlighted.
