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Q & A: drying fans

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Most recent answer: 07/23/2009
Q:
Hi there. I'm currently doing some research on lowering the moisture content on sugarcane leaves. I'm looking at sending the leaves through a sort of oven that has hot air flowing through it. I want to put fans blowing the hot air through the leaves, thus reducing the moisture content. I was wondering if you know of anything that could assist me in finding the optimum windspeed of the fans to blow the hot air(say at a temperature of 100 degrees celcius) to get a maximum drying affect. If the fans are blowing to much would this not cool the air down?
- Justin (age 22)
Pmb, RSA
A:
You should be able to measure the humidity in the air coming off with a fairly inexpensive device. (I'm getting something like that for my moldy basement at a cost of about $100.) You may need to adjust a relative humidity reading to an absolute humidity rating by measuring the temperature and using a standard conversion table. You may also need to know the background humidity (at the input) and the rate of air flow to calculate the net drying rate. It will be an interesting exercise to adjust both the heater power and the fan power to get the most drying for the least electrical power input.

Mike W.

(published on 07/23/2009)

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