Plant Revamps and Turnarounds: Some Lessons Learned

A plant turnaround is always challenging in the chemical process industries (CPI). But with proper planning and reliable procedures in place, last-minute time crunches and failures can be prevented. When haste combines with faulty methods, costly problems result. This article presents three examples of actual plant turnarounds and the lessons that can be learned from them.   Case study No. 1: Sour-water stripper A sour water stripper (SWS) is a relatively small unit that treats wastewater from other process units of the plant, in this case a petroleum refinery. After treatment, the wastewater is directed to the sewage system, wastewater plant and ultimately to a nearby river.   The plant This particular plant has no spare SWS unit, so in case of failure, the entire refinery must be shut down because untreated water is prohibited from being discharged into the river. A sour-water storage tank may be used in an emergency with a capacity for five days of normal wastewater accumulation. In the event that the SWS is down, it must be repaired and started within the five days, otherwise the entire refinery must be shut down as mentioned before. In this instance, the SWS column was packed with metal random packing. Column…