Effectiveness of Coatings to Reduce Fouling In Shell and Tube Heat Exchangers

Gabriel T. Fernandez and Talea A. Rothan. Process & Control Systems Department, Saudi Aramco, 12921, Dhahran 31311, Saudi Arabia

This paper studies the effectiveness of applying a coating on the tube side to resist fouling in reboilers on crude oil stabilizers. In this process, crude flows in the tubes of vertical reboilers heated by 60 psig (300 F) steam to stabilize crude oil to meet the True Vapor Pressure (TVP) and H2S specifications. Due to the high temperature, reboilers are subject to fouling predominantly on the crude side, resulting in low heat transfer and shut down for cleaning. Based on vendor claims on the effectiveness of coatings to reduce fouling and increase the interval between cleanings, a study was undertaken to compare the operation of one set of reboilers coated on the crude side (inside) with a protective coating on Column A, with another set of similar reboilers and similar operating conditions with no coating, on the adjacent Column B. The study was conducted for an interval of about 11 months and the results of this comparative study are presented in this paper.