tthut,

There are many different types and variants of product dryers, so many that an expert system is sometimes the best place to begin the selection process. The good news here is that one basic control philosophy, i.e. measurement of moisture in and moisture out, applies to all applications.

In continuous or batch processes dryer control can be effected using insitu moisture readings from the exit gas stream coupled with sampling / testing of the product in and the product out. This approach works well for residual moisture in the PPM range.

In batch drying processes where the acceptable residual moisture is, say, 1% or more a mass balance is possible using load cell readings coupled with sampling / testing of product in and product out.

As you can see product sampling / testing before and after is quite normal in most if not all drying processes.

I trust this helps.

Best regards,

Dennis Hauch ■

Hello tthut

I am doing research into simultaneous drying and pneumatic conveying, so I was very interested in your post. My project is a method of optimizing steady state performance. However I would very much like to make direct contact - I'm sure we could exchange information and expertise.

Please send me your contact details.

Thanks

Regards

Mark Kilfoil

Mechanical Engineering, Technikon Witwatersrand

Phone : 011 406 2300

E-mail : mkilfoil@mail.twr.ac.za ■