Large 1,000+ ton/day capacity Vertical Lime Kilns are possible, are very energy efficient and easy to operate. Minimal maintenance is required, because the limestone is brought to the top and into the kiln. Then the limestone is burned (calcined) for a specified time of hours to produce powdered lime. Then the lime is withdrawn at the bottom of the vertical kiln. 

The withdrawal at the kiln bottom regulates the gravity flow of limestone and controls the calcining retention time in the kiln. A clinkergrinding mill grinds any remaining chunks of limestone into powder. The lime is then transported by truck trailers or by rail cars. White cement is now very much in demand by the construction industry.