After calcination, the quicklime comes out of the kiln in lumps, grains, and powder. The quicklime, both in powder and granular form, is stored in silos before being shipped for various applications. Both quicklime powder and quicklime granules generate a great deal of dust during the filling and emptying process. It also tends to become sticky, creating rat holes and build-up on silo walls. Operators need to monitor and control the actual level of the material remaining in the silo in order to prevent disruptions of delivery schedules or the production process.