Vertical vs angled down commers

[Fireplace01]

Has anybody tried running slopped down comments in a plate just out of curiosity

[db1979]

What do you mean by sloped downcomers? Many have tried J shaped downcomers where they extend quite a long way across underneath the plate but as far as I know all downcomers are vertical above the plate. Some early bubblers I have seen had external downcomers.

[Fireplace01]

With industrial stills, they often tend to have a sloped or angled down Conner as it offers more surface area, just wondering if there are people out there doing this or not

[scythe]

No one here has done what you describe as far as i know.

[Thiele]

Sloped downcomer designs do offer a greater active area (slight) but the main reason for spending more money on a sloped downcomer in order to direct liquid flow from an upper to a lower tray is when there is an issue with vapour-liquid disengagement - if there is a lot of foaming for example. With ethanol-water distillation systems this isn't a huge problem.

I would be more concerned with the downcomer sizing rather than whether its straight or sloped. It's more important to avoid downcomer choking and backup flooding problems than to get a small benefit from an increase in active area. (need to estimate the optimum downcomer area, average velocity and pressure drop - which are almost always empirically determined. Sloped downcomer make it even more difficult to estimate)

Nerd for the day :-B