Lab scale air saturation

[MaxPlanck]

Hi all,

I have to build a new test setup for testing adsorption behaviour (kinetics, water uptake,...) of desiccant materials.

We need a conditioned air (temperature and humidity) which flows through and over the desiccant sample.
Regarding this conditioning of the air (humidity): we need a maximum flow of +- 15 kg / hour with a relative humidity of 100% at maximum 50°C at atmospheric pressure(also 100%RH at lower temperatures, but they are not the limiting factor).

Can anyone advise on the way how we can saturate this air flow? A saturator column with saddles and a continuous flow of water down the column and air going up?
Or can I use a vessel(s) with water where the air flow bubbles through? Maybe there are still other possibilities?

Many thanks in advance,
MaxPlanck

 

[hacksaw]

The national labs have such testing, it is far more complex a set up than the industrial process you are contemplating

 

[cheute79]

If you have to be precisely at 100% RH, you have a big challenge. If you can be 1-3% either way, then it's not so hard:

Suggest you use counter-current, up-flow packed column, slightly flooded. A sparger can gete you there, but the design, fab, and operating challenges are greater. Run the discharge (saturated) air at least 10°C higher than what you want, and pass the air through a condensor/heat exchanger large enough that you have only 5-10° approach, controlling cooling water flow from the discharge air temperature. This will get you quite close. I used to use this approach in a pilot plant I ran, and worked. The water has to be DI, better than softened, but not ultra-pure (>16Mohm).

If you need actual 100%, you probably need to use an ultrasonic vaporizing nozzle, ultra-pure water, special materials. You'll also have a challenge measuring 100% RH to prove it.