Say ‘No’ to FCCU Air Blower & Wet Gas Compressor Constraints

Introduction

Summer will be here sooner than we realize. It’s that time of the year when families pack up the car and head for the beaches, summer homes and amusement parks.   While a time of enjoyment for many, it puts refineries under significant pressure to ramp up gasoline production and keep pace with increased summertime demand. From a refiners’ perspective, it requires that they push even harder on certain equipment, such as the Fluid Catalytic Cracking Unit (FCCU), alkylation unit, and reformers to be able to meet that increased demand.   

However, at the very time that we are pushing our units to maximize gasoline production, we start to run headlong into the reality of running a plant in the summertime. Warmer ambient temperatures can negatively affect process units in many different ways.  

First, cooling water becomes warmer due to higher wet bulb temperatures, which affects every exchanger in the plant that uses cooling water. Fin-fans also become significantly less efficient due to a lower approach temperature. Given that most distillation towers use a combination of cooling water and fins-fans to condense overhead vapors, tower cooling capacity will likely diminish during the summertime. This forces plants to raise tower pressure in order to compensate.