(84c) Use of Ionic Modeling and Process Sample Analyses to Verify Causes of Corrosion and Fouling in Different Refinery Cases

A Refinery FCCU is critical to product blending, and an unplanned shutdown or rate reduction has large economic penalties. Water quality at a refinery can bring a unit down if heat isn’t adequately removed when needed. In the case study being presented, a reflux cooler had been fouled by calcium-phosphate in the water that precipitated out due to extreme skin temperatures. FCCU naphtha had been driven off spec by the warmer reflux. A coordinated effort between operations and utilities quickly recovered enough heat to enable the FCC to regain rate, saving $750K in lost revenue. The procedure was repeated four months later which gained an additional $450K for a total of about $1.3MM in rate reduction avoidance and avoided an even more expensive forced shutdown if the fouling had not been cleaned online. The methods used will be presented with PI graphs that show the speed by which results were achieved.