The chimney tray type collector is designed for one of two reasons:
1) draw-off a liquid product or pumparound stream or;
2) to combine the liquid from above with a liquid feed to the column before introducing the mixture to a liquid distributor above a packed bed.
At the same time that a chimney tray is collecting liquid, it must be designed to provide good vapor distribution to trayed and packed sections above it. A chimney tray can be designed with the chimney risers attached with either a bolted and gasketed construction or a seal-welded construction to enable liquid to accumulate on the tray without any leakage.
This vane collector is specialized for vacuum distillation columns where minimizing the column pressure drop is a key objective. Overlapping vanes catch liquid from the packed bed above and direct it to an annular trough where downpipes feed the liquid to high performance liquid distributors. This style of collector provides a very low-pressure drop by providing a high open area and little resistance to vapor flow since the vapor only makes a minimal change in direction as it passes through the collector.
AMACS recently received the patent for pressure drop reducing vanes, which further lowers the collector pressure drop.
While all other trays listed on this page have been for the intimate mixing of vapor and liquid, the chimney tray is a device specifically designed to keep vapor and liquid separate. The chimney tray, or collector tray as it is often called, is designed to collect liquid for one of two reasons: 1. to draw-off a product or pumparound stream or; 2. combine it with a liquid feed to the column before introducing the mixture to a liquid distributor above a packed tower. At the same time that a chimney tray is collecting liquid, it must be designed to provide good vapor distribution to trayed and packed sections above it.