Jan 03, 1998 Limestone Preparation The limestone feed is delivered by front-end loader onto the conveyor belt that originally fed the dryer. A new conveyor was installed directing the material outside the building to the new milling structure. It is received in a hopper, which feeds the mill by means of rotary valves. vertical for powders for limestone. vertical roller grinding mill LM series. vertical for limestone for coal grinding. vertical roller grinding mill LUM series. vertical for limestone for coal grinding. from *. 207,000. vertical roller grinding mill LUM series. vertical for powders for limestone. store by an underground rubber belt conveyor leading either to a hopper or direct to, for example, a cement raw mill. 7 1 Incoming belt conveyor 2 Jib 3 Conveyor belt, jib 4 Central column 5 Luffing unit 6 Jib counterweight 7 Operator cabin 8 Raking harrow 9 Raking car 10 Scraper chain 11 Hydraulic chain tension unit 12 Bogie 13 Outlet hopper