Sieve Trays

The sieve tray is a flat perforated plate with no moving parts. Vapor rises from the holes/ perforations to the tray above, cross-current to the liquid flow. The vapor energy keeps the liquid from flowing down through the holes. The latter moves across the tray and travels to tray below through down-comer. The sieve tray has good capacity and moderate efficiency compared to the valve tray and bubble cap tray, but has limited flexibility in the operating range.

The sieve size typically ranges from 1/4” to 1”. Smaller sieves reduce weeping whereas larger sieves are employed in fouling services.

The major advantages of the sieve tray is low maintenance cost and low fouling tendency when compared to other conventional trays. Also,the sieve tray is simple and easy to fabricate, and is relatively inexpensive compared to other mass transfer trays.