PNEUMATIC LIME/DOLO-LIME INJECTION SYSTEM IN OPERATION AT TENARIS DALMINE (ITALY)
On March 2008, Tenaris Dalmine (Italy) successfully started-up the pneumatic lime/dolo-lime injection system supplied by MORE srl (Gemona del Friuli,Italy) in their 100 ton electric arc furnace.
Tenaris is the leading global manufacturer and supplier of tubular products and services used in the drilling, completion and production of oil and gas; in process and power plants; and in specialized industrial and automotive applications with 21.500 employees world-wide and a total annual capacity of 6.000.000 tons.
Tenaris Dalmine is the steel pipe operations of Tenaris in Italy, it is the top Italian producer of seamless steel tubes for the energy, automotive and mechanical industries with outside diameters from 11/16 inch (17.2 mm) to 28 inch (711 mm), in carbon and alloy steel grades; the meltshop has an annual production capacity of 950.000 tons of finished products.
MORE pneumatic lime/dolo-lime injection system supply includes two MOLI dispensers (792 gal - 3000 liters capacity each) for pneumatic injection of lime and dolo-lime from the day-bins to the EAF shell. Two LIMEJET units are installed on board of the EAF shell, one dedicated for the lime and other for dolo-lime pneumatic injection. The LIMEJET is a combined burner/fluxes injector with 5 MW burner mode including the innovative MSF-Mixed Swirl Flame technology. MORE has supplied also the detail engineering for the manufacturing of the storage silo and accessories.
The pneumatic lime/dololime injection system in operation has demonstrated benefits in terms of continuous foaming slag conditioning, viscosity control by fluxes direct injection in the slag/metal interface and distribution during melting and superheating phases.
Improvement of refractory side bank protection has been achieved and the use of fine particles allows a faster solution and improves the material reactivity. The system manages the lime and dolo-lime melting process requirements via pneumatic transportation/injection technology, this eliminates the expensive maintenance for the conveyors belts transportation system from storage silos to EAF. From the environmental point of view, the technology eliminates the flux losses from the conveyors transportation system and consequently dust generation inside the meltshop building.
This further successfully installation, reconfirms the reliability and innovative technological content of MORE equipment in the steelmaking industry. At present, MORE has a scorecard of 25 EAFs with lime/dolo-lime pneumatic transportation/injection systems world-wide in operation or under manufacturing.