I D
× COMMENTARYCOVER STORYIN THE NEWSNEWSFRONTSCHEMENTATOR + Show More
Chemical EngineeringChementator Briefs
Self-healing adhesives Researchers at Oak Ridge National Laboratory (Oak Ridge,…
Chemical EngineeringModular NGL recovery
Honeywell UOP (Des Plaines, Ill.; www.uop.com) has adapted its recycle-split-vapor…
BUSINESS NEWSTECHNICAL & PRACTICALFEATURE REPORTFACTS AT YOUR FINGERTIPSTECHNOLOGY PROFILEEQUIPMENT & SERVICESFOCUS
Focus on Sensors
Oxygen measurement with Ex approvals & SIL2 certification The new…
NEW PRODUCTS + Show More

Comment PDF Separation Processes

How long does it take to reach steady state?

By Chemical Engineering |

How long does it take a six-tray, 4-ft dia. deisobutanizer to achieve steady state? That depends on your definition of “steady state”. Some control experts regard 95% of “ultimate value” as a good definition, but how useful is that definition? The FRI distillation columns are located on the Oklahoma State University (OSU) campus. As a result, there is a close relationship between FRI and the OSU chemical engineering dept., particularly with professors Rob Whiteley, Jan Wagner and Ken Bell. A couple of years ago, professor Whiteley and one of his graduate students, Anand Vennavelli, performed a set of time-to-steady-state (TTSS) tests using the FRI experimental unit. They found that hydraulic equilibrium was achieved fastest when a column was operated at atmospheric pressure and two times slower at vacuum and at high pressure. They found that the key to reducing TTSS, was pressure control. Several years ago, FRI’s membership instructed the FRI staff to study the impact that reflux temperature has on packing performance. The membership wondered whether renegade condensation on the outside of liquid distributors was shifting the control of the distribution from the distributors to Mother Nature. FRI purchased…
Related Content

Chemical Engineering publishes FREE eletters that bring our original content to our readers in an easily accessible email format about once a week.
Subscribe Now
Steel Belt Units for Medical Membranes
Upstream Oil & Gas: Automation intelligence from wellhead to distribution
Video - CoriolisMaster
Video - Do you really need a thermowell?
The influence of IIoT in the dewatering process step of pigment production

View More