Investigations of high pressure drop observed in ASU columns

The measured pressure drop of columns in air separation units (ASU) is often reported as being higher than the predicted pressure drop. Particularly for high-pressure (HP) columns, the difference can be up to four times higher, depending on the operating pressure of the column. To investigate the difference, the operation data of recently revamped HP columns were collected; then, vapor and liquid loads as well as their physical properties were generated using a process simulation tool. Thereafter, a proprietary hydraulic rating toola was utilized to predict the dynamic pressure drop caused by the column internals. The use of the differential pressure transmitter and its connecting piping ins