I don't know if this really justifies it's own thread, but anyway:

SWIM has recently moved his operation to a shipping container,
and as it's now winter and the use of electricity there would be
unfeasable, this makes for an interesting situation:

As we extract at hotter temperatures, the naptha will disolve
all substances more readilly. This includes plant fats and
oils. So, swim is expecting some nice white spice with relatively
little oil contamination (yellowing)

How much longer will it take to evaporate a plate of naphtha at
near zero?

A hell of a lot longer obviously. I don't think anyone could give you exact figures. Why not move the final spice filled solvent to somewhere where a fan can be used? Run an extension cord somewhere maybe.

Your "operation"? Wow, sounds pretty serious.

I guess sWIM will be able to report back exactly how much longer at some point in the future.

Doesnt that depend on the relative humidity and air flow around it?

I dont know. Seems to me that dry cold might work as well as very humid warm? Maybe not. lol. Hey! I never claimed to be very bright regarding these matters. I am interested in how this works.

Yes absoloutely, my graph really should be evaporation rate vs. humidty/temperature/windspeed.
Well, I asked a question on yahoo answers, and got a good answer;

seems that the rate of evaporation is more or less linear with temperature, not exponential as I had feared
(which would make for a *really* minimal evaporation rate at near 0.)

that and the fact that it's in a fairly dry place, although cold, should
boost evaporation.

HA! Look at the brain one Ice House!

Even a Knucklehead makes a lucky guess once in a while!

For sure, when I evaporate either naptha or xylene on a pyrex dish with a fan over it on a cold winter day the results are much better and quicker than on a warmer more humid day. No chart to back tha up, just personal experience.

First i'd just like to report that evaporation near 0*C is *painfully* slow, but it is occuring.
SWIM filled a petri dish up with some naptha pulls, almost right to the brim. Nearly a week and a
half later it's decreased by maybe 3 -4 mm. Actually not bad when you think about it.
But I guess at that rate it'd take you almost three weeks per batch.





Well, SWIM bought a little too much MHRB, so he has to store it in demijohns. He'd call that an 'operation'.
SWIM's chemistry 'kit' is also not too bad tbh!


@Madbanshee: thanks for the info, this concurs with what I have learned too. Snowy days are dry.

It sounds like you're not using a fan to help the evap process.

Swim filled a baking dish halfway with Xylene, (which evaps slower than naptha,) and it all was evaped in 2 days.
He uses a small computer type fan mounted on a 1/4 inch sheet of plastic and placed over the dish. Otherwise this would have taken weeks to dry instead of 2 days.

I just noticed that you say you have no electricity where you're drying, so get a car battery. The fans are usually 12v and running off a car battery one of these fans would run for many days. Swim uses a 12v fan that is about 1/3 the size of the standard computer fan. His fan is about 2" square and works great.

Also, break it up into several dishes and several fans.