The MVG tray with standard downcomers was tested at Fractionation Research, Inc. (F.R.I.) and was proven to have a unique combination of very high capacity as well as high efficiency, particularly in low to moderate liquid rate applications.
Extensive commercial experience has also shown the decks to have much better fouling resistance than sieve decks. These characteristics make MVG decks ideal for low to moderate pressure distillation applications. MVG technology provides a vapor side capacity improvement of 10-20% simply by changing out the tray decks.
A separate test of the MVGT tray has recently shown a capacity improvement of 25% over a well designed valve tray in the 100 psia butane test system. The downcomer portion of the MVGT uses a high performance truncated downcomer. In conventional trays, the downcomer generally extends within a few inches of the tray deck below. In truncated downcomers, the downcomer is shortened so that it stops several inches above the tray deck.
This technique allows much of the area below the downcomer to be used as bubbling area to Improve the tray capacity. Depending upon the process requirements and the tray configuration, a truncated downcomer can improve capacity by 5-20%. When used in combination with MVG valves, the resulting MVGT tray can provide a capacity improvement of 15-40% over conventional trays, typically with improved efficiency as well.
MVGT trays have been used successfully in a wide variety of applications ranging from refining, gas processing, petrochemical and chemical. Unlike many other high capacity trays that have reported failure rates as high as 40%, the MVGT tray, with its robust design, has never had a reported failure since its introduction in 1995.
