Refinery Turnaround

A turnaround is a planned, periodic shut down (total or partial) of a refinery process unit or plant to perform maintenance, overhaul and repair operations and to inspect, test and replace process materials and equipment. Here are some key facts:

• Turnarounds allow for necessary maintenance and upkeep of operating units and are needed to maintain safe and efficient operations.
  
  
• Turnarounds are scheduled at least 1-2 years in advance and do not necessarily focus on the same operating units.
  
  
• Delaying a turnaround can increase the ultimate turnaround cost by 20% - 50% or more but may be done if the margins make it economically justifiable and there are not overriding safety concerns.
  
  
• In assessing whether to delay a turnaround, a refiner has to include the opportunity cost of a possible unplanned shutdown resulting from the decision to delay the turnaround.
  
  
• Depending on the process unit and the amount of maintenance needed, the length of the turnaround can vary from 1 week to 4 weeks or more.
  
  
• A major turnaround usually will involve the crude unit or the catalytic cracking unit and will result in a more significant decrease in the utilization rate than a minor turnaround that may involve units such as the alkylation unit, isomerization unit or sulfur plant.
  
  
• Not every unit is impacted during every turnaround. For example, the industry average is about 4 years between turnarounds catalytic cracking units.
  
  
• A turnaround is not necessary to enable a refinery to shift from gasoline mode to distillate mode. However, if a turnaround is planned, it is possible to take steps, such as catalyst upgrades, that could improve the distillate yields.
  
  
• In general, the less often units are started up and taken down, the better (safer) it is since refinery incidents are more likely to occur during these occasions.