Naphtha products may suddenly assume a yellowish cast and then return to a normal water-white condition. If this proves to be a recurring problem, the…
Category: Process Troubleshooting
Operators may attempt to maximize heavy naphtha production at the expense of light naphtha by increasing the fractionator top reflux rate, which drops the tower…
Operators are usually more interested in making on-spec products than in saving energy. In the field one will often find pumparound rates cut back to…
Hot vapors, flowing up the fractionator from the flash zone, are partially condensed by contact with cooler pumparound liquid. The heat absorbed by the pumparound…
Although trays can corrode through, a more common cause of damage is unit upsets. A high liquid level, above the flash zone, will cause the…
Accounting for a loss in fractionation is a common troubleshooting assignment. For example, crude unit operators find that they can no longer meet furnace oil…
A large carry-over of coke or partially coked resid from the coke drum is called a foamover. Preventing such foamovers is vital to continued operation…
While the continuous aspect of delayed coking is straightforward, problems arise in the batchwise filling and emptying of coke drums. The table below summarizes a…
Coking is an old process but one that is becoming more important as the quality of the world’s crude supply deteriorates. As the sulfur, metals,…