Recirculating as you describe is an inefficient way of blending material unless you can withdraw from many different locations from within the silo.

Have you considered converting the silo to an homogenizing silo design to obtain a more efficient blend factor?

Regards ■

Converting would require adding significantly more aeration devices and air supplies to fully aerate and fluidize the material to make the blending more effective

If you have a drawing of the existing silo available, I'd be happy to take a quick look to see what all would need to be done.

If you have it electronically, send it to my e-mail address below

regards ■

Homogenizing and blending are two very different processes. Homogenizing is done to reduce variations within the same material whereas blending is done to blend two or more different materials.

Cement and fly ash are two very different materials. In my opinion, the process that you need is blending, not homogenizing.

Aeartion, or fluidizing, is effective in homogenizing the same material but not two widely different materials because of the differences in their fluidizing velocities.

Your idea of recirculating silo contents is correct but you will have to convert the silo into a blending silo. This will require use of internal tubes in the silo. A number of vendors offer these blending tubes. You may contact them to evaluate different tube designs.

Regards,

Amrit Agarwal

Consulting Engineer

Pneuamtic Conveying Consulting

Email: polypcc@aol.com

Ph and Fax: 304 346 5125 ■