For those of you who haven't heard of mechanical
steam compression clothesdryers, they work like this:
First, the tumbler and the clothes are heated up to
100C; the steam that's initially produced displaced all of
the air, resulting in a steam-only atmosphere inside the
machine. Some of that
steam is taken out, compressed
(raising it's temperature), passed through the inside of
the condenser; the resulting liquid water exits the
condenser via either a float valve or a pressure release
valve, and is discarded down a drain. Some of the
steam from the tumbler is pulled out via a blower, sent
around the outside of the condenser (which superheats
it), then blown back into the tumbler.
Such machines are both energy efficient and fast at
drying clothing, but have one really big downside: They
operate at a range of 100C - 120C, and are not suitable
for heat sensitive clothing types.
I propose modifying this existing technology, by putting
the components into a vacuum chamber, and adding a
gas/liquid separator, an additional compressor, and a
When the system is initially turned on, air is pulled from
the dryer by the primary compressor, passed through
the separator, then the secondary condenser, then
A float valve in the gas/liquid separator will, when
liquid is present, turn off the secondary condenser and
turn on the condensate pump; this pump pulls water out
of the separator and discards it.
As with a regular MSC clothes dryer, a blower pulls gas
(either air or steam, depending on the drying phase) out
of the tumbler, past the condenser, and back into the
In addition, there is a thermocouple, with one end
inside of the gas/liquid separator, and the other on the
outside of the machine. If the temperature in the
separator is below the temperature of the room, the
secondary compressor is turned off, even when there's
no liquid in the separator. This keeps the system's
overall temperature close to ambient, which maximizes
efficiency. This also keeps system temperatures well
above the freeze-drying range.
As a result, we now have a clothes dryer which is just
as fast and efficient as MSC, but which operates at near-
ambient temperatures, and should be suitable for all
types of clothing.
Caution: If you accidentally put a pen in the dryer with
your clothes, it's guaranteed to explode and make you
unhappy, as the pressure drop will make the ink boil and
expand out of the pen.
Optional: A feature to run the system with the tumbler
not spinning, so it can be used to make homemade dried
foods. Use of a battery powered fan for circulation is
suggested. Cleaning or replacing the filter when
switching from making dried food to drying clothes is
strongly recommended (unless of course you *want* to
smell like jerky).