Challenge

An 80,000 bbl. /day crude distillation unit underwent a month long planned shutdown in order to perform maintenance on their exchangers, and pressure vessels. The shutdown began with the de-inventory and decon of the unit, often heralded as an unavoidable slow measure. Depressurizations, high flow nitrogen sweeps, and liquid deinventory can lead to many unanticipated delays. Due to the relatively small size of the unit, footprint was a concern, which added an additional layer of hazards.

Solution

Fortunately for this refinery, Envent designed, engineered, and executed a system that mitigated any potential hazards, as well as effectively and efficiently decreased decon time by three whole days. Liquid carryover was mitigated by adding low point drains in strategic sections of the process lines. Barriers were erected to limit foot traffic through the small footprint. Hose diameters were upsized to reduce pressure drop and allow for higher flows during depressurizations. Additionally, an injection port was installed into the process line to allow for enrichment of high nitrogen flows. These and many other factors contributed to Envent’s success in this turnaround, which shaved off three entire days from the refinery’s schedule!

Benefit

The refinery Turnaround planning team, anticipated at least seven days of runtime with Envent equipment. However, once process began to flow into the thermal oxidizers, higher flows were achieved. This allowed the refinery to complete their objections within four days! Once shutdown was complete, all equipment was removed, cleaned, and out of the refinery within 48 hours of job completion. A refinery turnaround lead summarized it best,” I want to express my appreciation for a job well done! The Envent team showed professionalism and a spirit of team work that allowed us to turn over the unit ahead of our original schedule…Thank you and we look forward to upcoming projects with Envent.”