Bulk Tankers & Aeration

This will explain it to you better than I could.
http://www.solimarpneumatics.com/pdfs/2012_SwingAwayHopper_ProductSheet.pdf

 

It is very common to only use aerators for heavy product like cement, fly ash, sand, lime kiln dust, and hi-cal quicklime. Our cement trailers didn't even have top air.

For hydrated quicklime ("hydrate"), we used top air, no aerators, and very little jet line. Hydrate is a very light, fluffy product.

For dolomitic quicklime ("dolo,") we had to use equal parts top air and aerators. No more than 12 PSI tank pressure, or the product would stay against the sides of the trailer instead of falling into the hopper valve. It was even lighter and fluffier than hydrate, so much so that the plant's loading equipment had to blow it into our trailers under pressure.