EFFECTS OF RESINS/ASPHALTENES RATIO ON HEAT EXCHANGER FOULING OF MIXTURES CONTAINING HEAVY OIL

Asphaltene precipitation from oils depends on the composition of solvent components such as resins and aromatics. Fouling of asphaltenes from a heavy oil in mixtures of fuel oil and de-asphalted vacuum bottoms was studied at asphaltene concentrations of 0.04 − 3.36 %, and resin concentrations of 3.1 − 4.9 %. Fluids under nitrogen were recirculated at 85°C through an annular test section with initial surface temperature of 230°C for periods up to 30 hours, and the fouling monitored by thermal measurement. The effects of concentration of heavy oil and de-asphalted oil are explored. Fouling rates are correlated with the ratio of resins / asphaltenes.