[kurthr]

Why not just use a vacuum pump and pull the water vapor out at a constant temperature. You can flow 33C dry air (use a condenser before expanding and heating, if you like) across the clothes as they tumble to keep them from freezing.

You wouldn't have to pump below a 10% of an atmosphere to quickly dry your clothes (vapor pressure of water is 5% of an atmosphere at that temp).

To give an idea of how fast: With a 1liter/sec STP air intake, you would extract ~1gram/sec of water so in 15min you would remove ~1kg of water.

[kortex]

And with the air mostly removed, you can spin the drum really really fast! I think you're on to something here. :P Maybe not.

I've done hundreds of solvent evaporations under vacuum (rotovap). The problem is you need a trap, or else solvents condense in the pump which causes your efficiency to go down. So now you need a heat pump or similar, now you're talking about a really complicated dryer. But it'd be efficient.

[kurthr]

Yeah, thanks for the comment on the condensation.

The output pump would really need to mostly pump water and vapor at the input and liquid at the output, but not to very low pressure... even a peristaltic might be doable (no rotary vane/blower needed). It was just a thought, I used to rotovap too so running through the calculations seemed like a fun idea.